Bacteriology Exam 1

Front 1

T/F: Archae are mostly thermophiles.

Back 1

True

Front 2

What are the 3 kingdoms?

Back 2

Bacteria, Archae, Eukarya

Front 3

What is the 3 kingdom classification system based on?

Back 3

Sequences of ribosomal RNA

Front 4

Bacterial taxonomy is concerned ___, ____, and ___.

Back 4

Classification
Nomenclature
Identification

Front 5

T/F: bacterial identification is based solely on morphological traits.

Back 5

False: bacterial identification is based on morphological, biochemical and serological traits as well as the nucleic acid profile

Front 6

What morphology of bacteria grow in chains of circles?

Back 6

Streptococcus

Front 7

What morphology of bacteria grow in clusters of circles?

Back 7

Staphylococcus

Front 8

What morphology of bacteria grow in rods?

Back 8

Bacillus

Front 9

What arrangement of bacteria results in tetrads?

Back 9

Sarcinae

Front 10

What are the generic layers of the wall of a typical prokaryotic cell?

Back 10

Cytoplasm
cytoplasmic membrane
cell wall
capsule

Front 11

Describe the process of bacterial spore formation.

Back 11

plasma membrane pinches off around the daughter DNA, but remaining in the same cell wall of the parent cell. The plasma membrane of the parent DNA re-envelops the daughter DNA creating a double membrane around the forming spore (forespore). The endospore is relased from the parent cell.

Front 12

Teichoic acid and lipoteichoic acid are important components of what part of the cell?

Back 12

Cell wall (G+ only)

Front 13

What is the important component and cellular structure involved in the purple staining of gram positive cells?

Back 13

Peptiodoglycan in the cell wall

Front 14

Why do gram negative bacteria stain pink?

Back 14

The thin layer of peptidoglycan is more porous allowing the violet/iodine complex to escape. The pink stain we see is due to the saffarin.

Front 15

T/F: penicillin targets amino acid bonds between the tetrapeptides in the peptidoglycan layer

Back 15

True

Front 16

What cellular component does lysozyme target?

Back 16

M-G linkage in the peptidoglycan neetwork.

*M: n-acetyl-d muramic acid
*G: n-acetyl-d glucosamine

Front 17

lysozyme and penicillin attack what part of the cell? This causes the cell to do what?

Back 17

Cell Wall

Cytoplasmic Membrane blebbing.

Front 18

What is different about the cell wall of acid fast bacteria?

Back 18

They have Mycolic Acid: linked to muramic acid and arabinogalactans by phosphodiester links and glycolipid links respectively

Do NOT have: teichoic acid

Front 19

Corynebacterium, Nocardia, and Mycobacterium are examples of what type of bacteria?

Back 19

Acid Fast

Front 20

Acid Fast bacteria are what color? Why?

Back 20

RED: resistant to acid decolorization

Front 21

What do isoniazids target?

Back 21

Mycolic Acid

Front 22

The R chain of the Fatty acids in the cell wall of acid fast bacteria is (short, same, long) in comparison to Gram positive bacteria.

Back 22

LONG

C32--C90: makes it very tough to penetrate.

Front 23

Of gram positive, gram negative, and acid fast bacteria, which has the thickest cell wall?

Back 23

Acid Fast

Front 24

Name 3 non-peptidoglycan components of the cell wall.

Back 24

Flagella
glycocalyx
pili

Front 25

H antigens are associated with what cellular structure?

Back 25

Flagella

Front 26

K antigens are associated with what cellular structure?

Back 26

Glycocalyx

Front 27

The capsule/slime layer is also known as ___.

Back 27

Glycocalyx

Front 28

Glycocalyx is made of ____.

Back 28

Glycoproteins

Front 29

There are two types of pili:

Back 29

1- adhesion (fimbrae)
2- sex pili

Front 30

T/F: The cell envelope of gram positive and gram negative both have teichoic acid.

Back 30

False: only gram positive has teichoic acid.

Front 31

Tetrapeptide units
beta 1-4 linked glycans
diaminopimelic acid
d-amino acids

These are components of the ____ in the bacterial cell.

Back 31

peptidoglycan layer

Front 32

Bacterial taxonomy is concerned with latinization of names and classification based on ___ and ___.

Back 32

Nomenclature and Identification

Front 33

Teichoic acid residues are characteristic of the cell envelope of ___.

Back 33

gram positive bacteria

Front 34

Streptococcal arrangement:

Back 34

linearly arranged cocci

Front 35

Name 3 uses of bacterial pili:

Back 35

1- facilitate conjugation
2- transfer DNA
3- transfer episomes
4- attach to host surfaces

Front 36

antibodies that react with carbohydrate residues in the LPS are reacting with which antigens?

Back 36

O-antigens

Front 37

K antigen is associated with what cell structure?

Back 37

Capsule

Front 38

Capsules are like a slime layer that inhibit 2 main immune functions:

Back 38

1- inhibition of antibiotic uptake
2- inhibition of phagocytosis

Front 39

An alkaline pH reaction produced by bacteria is generally the result of the metabolism of:

Back 39

amino acids

Front 40

bacterial mycolic acids are responsible for:

Back 40

acid fast reaction (Red)

Front 41

T/F: Counterimmunoelectrophoresis is a technique which combines electrophoresis and immunodiffusion.

Back 41

True

Front 42

Counterimmunoelectrophoresis uses current to move ____ toward the positive pole.

Back 42

bacterial antigens

Front 43

Counterimmunoelectrophoresis allows for antigen detection in the absence of a _________.

Back 43

pure isolate culture

Front 44

Antibodies in counterimmunoelectrophoresis move toward the negative pole by ____.

Back 44

immunodiffusion

Front 45

Triple sugar iron agar is what type of medium?

Back 45

differential medium

Front 46

Antibodies recognize what antigen on capsules?

Back 46

K antigens

Front 47

How do you isolate homogenous cultures for the purpose of identification? name 2 ways.

Back 47

streak plate
serial dilutions + plating out
streaking on selective medium
streaking on differential medium

Front 48

1. The microorganism must be found in abundance in all organisms suffering from the disease, but should not be found in healthy animals.
2. The microorganism must be isolated from a diseased organism and grown in pure culture.
3. The cultured microorganism should cause disease when introduced into a healthy organism.
4. The microorganism must be reisolated from the inoculated, diseased experimental host and identified as being identical to the original specific causative agent.

Back 48

Koch's Postulates

Front 49

What are Koch's postulates used for?

Back 49

Identificaiton of a Bacterial Pathogen

Front 50

Salmonella cholerasuis is a facultative anaerobe that could be readily isolated from a fecal sample if cultured on ___.

Back 50

MacConkeys agar at 37C

Front 51

Bacterial motility is indicative of what organelles?

Back 51

flagella

Front 52

bacterial fermentation in the diagnostic lab setting refers to utilization of ____.

Back 52

carbohydrate

Front 53

decarboxylation, desulfurylation and deamination are indicative of _____ _____.

Back 53

Protein catabolism

Front 54

Slide agglutination tests can target what organelles?

Back 54

Flagella protein-- H antigen
LPS polysaccharide-- O antigen
Capsule protein/polysaccharide-- K antigen

Front 55

an alkaline reaction in the slant portion of a triple sugar iron agar medium is indicative of ____.

Back 55

Deamination

Front 56

anabolic and catabolic pathways, ATP synthase, oxidative phosphorylation, and electron transport are involved in ______ in bacteria.

Back 56

the chemiosmotic production of ATP

Front 57

T/F: The synthesis of proteins in an anaerobic bacterial species gown in glucose as the primary carbon source involves oxidative phosphorylation.

Back 57

False: it involves anabolism, catabolism, anaerobic respiration, and ATP production

Front 58

A black reaction in the butt and slant portions of a TSI agar medium is indicative of:

Back 58

desulfurylation

Front 59

What class of bacteria would grow in the temperature range of 55-65C?

Back 59

Thermophiles

Front 60

A ______ medium is designed to favor growth of one bacterium over another based on metabolic capabilities.

Back 60

Selective

Front 61

desulfurylation reactions in bacteria result in the production of

Back 61

hydrogen sulfide

Front 62

MacConkey's agar is good for growing what class of bacteria?

Back 62

gram negative facultative anaerobes

*salmonella cholerasuis

Front 63

What is the metabolic class of most bacteria?

Back 63

Chemoheterotrophs

Front 64

Chemoheterotrophs get their ___ from organic compounds for ____, and use CO2 as a carbon source.

Back 64

electrons, energy

Front 65

R factors and F factors are the same minus one detail which is that:

Back 65

R factors have genes encoding virulence determinants (resistance)

Front 66

The ability of bacteria to adapt to their environments is dependent on their ability to __________________.

Back 66

acquire genes through conjugation

Front 67

Transposons can aid the development of antibiotic resistance in bacteria via:

Back 67

insertion of sequences to mobilize resistance genes

Front 68

DNA adsorption
DNA penetration
DNA recombination
competence site

Requirements for what bacterial function?

Back 68

Transformation

Front 69

In order for naked DNA to bind to a bacterium, it must be

Back 69

competent

Front 70

A bacterial donor cell carrying an F+ episome will cause the recipient cell to become

Back 70

F+

Front 71

Transduction refers to:

Back 71

Transfer of bacterial genes by a phage.

Front 72

How does a transposon cause a mutation?

Back 72

Recombination into a new location on the chromosome.

Front 73

T/F: Plasmids promote conjugation.

Back 73

FALSE: R and F factors promote conjugation.

Front 74

How can phages be used to identify bacteria?

Back 74

Phage binding to specific cell envelope receptors allows for the determination of susceptibility to the bacteriophage

Front 75

Antibiotics that attack ribosomes inhibit:

Back 75

protein synthesis

Front 76

What type of antibiotic kills the bacterial pathogen?

Back 76

bacteriocidal

Front 77

Fluorquinolones are antibiotics that inhibit ____.

Back 77

DNA replication/ synthesis

- DNA gyrase

Front 78

How does penicillin work?

Back 78

prevents bacterial growth by inhibiting peptidoglycan cross-linking.

Front 79

Streptomycin is in what class of Antibiotic?

Back 79

Aminoglyoside

Front 80

Aminoglycosides work by several mechanisms. Name 2.

Back 80

Plasmid mediated resistance
impaired transport
decreased ribosome binding
aminoglycoside altering enzyme

Front 81

beta lactamase is an enzyme responsible for the disruption of what class of antibiotics?

Back 81

Penicillins

Beta lactams

Front 82

T/F: Replication can mediate an antibiotic resistance gene into a non-antibiotic resistant bacterium.

Back 82

False:
only Transduction, Transformation, RTF, Conjugation.

Front 83

Why is Bacitracin limited to topical use?

Back 83

it disrupts membranes of both eukaryotes and prokaryotes.

Front 84

Trimethoprim is an antibiotic that works as an _____ to inhibit bacterial growth.

Back 84

Anti-metabolite

Front 85

Isoniazid is effective against Mycobacterium because the antibiotic inhibits ___.

Back 85

Mycolic acid synthesis

Front 86

Immunoblot of a protein extract gives information on___.

Back 86

size of a protein that reacts with a specific antibody

Front 87

Licensed veterinary vaccines are approved by ____.

Back 87

USDA

Front 88

What is one of the main problems with DNA vaccines?

Back 88

gene silencing by immunized host

Front 89

DNA vaccines are good for several reasons, name 2.

Back 89

Easy purification of DNA
Increased stability relative to proteins
Cost
low risk of causing disease

Front 90

An affinity TAG encoding 6 histidine residues allows for chromatographic purifiication of a recombinant protein because the protein will bind to ___.

Back 90

nickel

Front 91

What's in a naked DNA vaccine?

Back 91

a gene encoding a protective antigen

Front 92

What are some of the current limitations of vaccines?

Back 92

-silencing of DNA vaccines by host
-expense due to mixing of adjuvants
-federal regulatory hurdles
-reversion of naturally ocurring mutants to disease causing state

Front 93

Vaccine Brucella abortus RB51 protects cattle by the introduction of ___.

Back 93

ribosomal proteins

Front 94

What is a transposon?

Back 94

mobile genetic elements

Front 95

Over-production of a recombinant protein in bacteria is dependent on:

Back 95

transformation

Front 96

A mutation created using allelic exchange is a result of

Back 96

recombination between the wild type gene versus the plasmid born disrupted gene

Front 97

T/F: Biodegradative pathways are catabolic and consume ATP.

Back 97

False: Biodegradative pathways are catabolic, but they PRODUCE ATP.

Front 98

Biosynthetic pathways are anabolic and they (produce/consume) ATP.

Back 98

Consume

Front 99

Name the 3 mechanisms of energy production in Bacteria.

Back 99

Fermentation
Respiration
Photosynthesis

Front 100

Fermentation occurs under what type of O2 conditions?

Back 100

aerobic and anaerobic

Front 101

Substrate-level phosphorylation occurs when a Phosphate group is taken from one compound and added to an energy compound (ADP). When does this occur?

Back 101

Mainly glycolysis, but also in the Kreb's Cycle

(succinyl coA--> succinate: GDP--> GTP)

Front 102

Under Aerobic conditions Oxidative Phosphorylation passes ___ to ____ to yield ____ and ____.

Back 102

H+
Electron Transport Chain
ATP and H2O

Front 103

How is oxidative phosphorylation different under anaerobic conditions vs aerobic conditions?

Back 103

under anaerobic conditions, the final e- acceptor is an organic compound instead of O2 (to make water)

Front 104

ATP synthesis (electron transport) takes place where?

Back 104

Inner mitochondrial membrane

Front 105

T/F: During electron transport ATP generation, protons are pumped across the inner mitochondrial membrane at 4 points, one for each complex.

Back 105

False: the protons are pumped across the membrane at 3 points.

Front 106

Name a few of the different end products of Pyruvic acid as a result of microbial fermentation.

Back 106

Streptococcus, bacillus --> Lactic Acid

Clostridium--> butyric acid, acetone, isopropyl alcohol, CO2

Enterobacter--> Ethanol, lactic acid, formic acid...

Front 107

What nutritional class of organisms use light and CO2?

Back 107

Photoautotroph

Front 108

What nutritional class of organisms use light and organic compounds?

Back 108

photoheterotroph

Front 109

What nutritional class of organisms use electrons from inorganic compounds and CO2?

Back 109

chemoautotroph

Front 110

What nutritional class of organisms use organic compounds for energy and carbon?

Back 110

chemoheterotroph

Front 111

Bacteria with proteases have a distinct advantage because they can break down ____ and use them as substrate.

Back 111

Macrophages

Front 112

What is the ideal temperature range for thermophiles?

Back 112

55-75C

Front 113

What is the ideal temperature range or mesophiles?

Back 113

30-45C

Front 114

-5 --> +5C is the ideal temperature range for what class of bacteria?

Back 114

Psychrophiles

Front 115

Why are anaerobic bacteria nonviable in aerobic environments?

Back 115

they lack superoxide dismutase

Front 116

What is the difference between microaerophilic and facultative anaerobe?

Back 116

microaerophilic -- requires small amounts of oxygen to survive

facultative anaerobe -- capable of energy production in aerobic and anaerobic environments. (whereas obligate anaerobes would die in the presence of O2)

Front 117

Brucella require subculturing in a _____ environment initially.

Back 117

microaerophilic

Front 118

T/F: The Maximum Range is the best for bacterial growth whether it be temperature or pH.

Back 118

False: Growth is SLOW in the Maximum and Minimum ranges as they are survival ranges. The middle optimum range promotes the fastest bacterial growth.

Front 119

What are the two basic types of culture media?

Back 119

Defined/simple and Enriched/complex

Front 120

What type of media has every ingredient known and measurable?

Back 120

Defined/Simple

Front 121

What type of media supplies MOST of the required nutrients to support growht of MOST bacteria? (don't know every ingredient measure)

Back 121

Enriched/Complex

Front 122

MacConkey's agar is what type of Media?

Back 122

Differential:
bacteria's ability to ferment lactose
Lactose fermentors: pink
Non-lactose fermentors: yellow

* It is also selective for growth of gram negative bacteria.

Front 123

MacConkey's agar grows Gram ___ bacteria.

Back 123

Negative

Front 124

What type of media would be used to ensure survival or proliferation of a cell type with certain properties?

Back 124

Selective

Front 125

Selenite broth is what type of media?

Back 125

Selective

Front 126

Selective media has ingredients that can (enhance/suppress/both) a specific bacteria.

Back 126

Selective media can be designed to enhance or suppress

Front 127

Enriched media are used for Fastidious organisms that have ___.

Back 127

Complex nutrient requirements

Front 128

Blood Agar is what type of media?

Back 128

Enriched

Front 129

Stewart's media is a type of Transport media that used to:

Back 129

minimize overgrowth of pathogens and preferably keep bacteria cultured in the same proprotion as the original sample.

Front 130

T/F: Stewart's transport medium is NOT readily Metabolizable.

Back 130

True

Carbon source only supports viability, but not Growth.

Front 131

What is Agar?

Back 131

Polysaccharide that causes gel formation.

Front 132

What is a "metabolic footprint"? Why is it important?

Back 132

characteristic by-products associated with metabolism--> can be used to identify bacteria

Front 133

T/F: Glycocalyx is only found on Gram negative bacteria.

Back 133

False: Glycocalyx is found on BOTH gram positive and gram negative bacteria

Front 134

Glycocalyx is highly antigenic. It can be used to provide serotype information by ___ antigens.

Back 134

K antigens

Front 135

H antigens are found in what part of the cell?

Back 135

Flagella

Front 136

What is the goal of Quadrant streaking?

Back 136

Isolated colonies

Front 137

Serial dilutions requires interpretation of colony numbers. In order to determine whether an infection exists you multiply: ___ by____ which gives you an estimate of the bacterial numbers in the original sample.

Back 137

number of colonies on the plate x dilution of the sample (for that plate)

Front 138

T/F: MacConkey's agar is selective and differential.

Back 138

True:
Selective against Gram positive (only grows gram neg.)

Differential for lactose utilization.

Front 139

What is the average time frame for incubation of cultured plate colonies?

Back 139

18-24 hours

Front 140

What are some of the characteristics that should be recorded when noting colony growth?

Back 140

surface, shape, elevation, margins, size, color

Front 141

Wet mounts are good for determining bacterial ___.

Back 141

motility

Front 142

Name one other motility test other than a direct observation in a wet mount.

Back 142

Soft agar stab in a motility culture medium

Front 143

What effect does Antibiotics have on bacterial motility?

Back 143

Ab will bind to flagella because it is highly antigenic, and so bacteria may appear immotile on a culture from a patient on Ab.

Front 144

H antigens, O antigens, and K antigens are used for what type of bacterial identification test?

Back 144

Serological

ie: slide agglutination, ELISA, counterimmunoelctrophoresis,

Front 145

What is one of the easier and inexpensive serology tests that can be run to ID a bacteria?

Back 145

Slide Agglutination

Front 146

At what pH is the average bacterial antigen negative?

Back 146

pH= 8

Front 147

Name one other motility test other than a direct observation in a wet mount.

Back 147

Soft agar stab in a motility culture medium

Front 148

What effect does Antibiotics have on bacterial motility?

Back 148

Ab will bind to flagella because it is highly antigenic, and so bacteria may appear immotile on a culture from a patient on Ab.

Front 149

H antigens, O antigens, and K antigens are used for what type of bacterial identification test?

Back 149

Serological

ie: slide agglutination, ELISA, counterimmunoelctrophoresis,

Front 150

What is one of the easier and inexpensive serology tests that can be run to ID a bacteria?

Back 150

Slide Agglutination

Front 151

At what pH is the average bacterial antigen negative?

Back 151

pH= 8

Front 152

What is a Durham Tube used to detect?

Back 152

Carbohydrate use via fermentation.

Front 153

What is a positive result in a Durham tube?

Back 153

Gas bubble in the inverted tube.

Front 154

In Counterimmunnoelectrophoresis, antigen moves toward ___ pole and antibody moves toward the ____ pole.

Back 154

Antigen--> positive pole (usually negative at pH= 8)

Antibody --> negative pole carried by the buffer

Front 155

Advantages of Counterimmunoelectrophoresis:

Back 155

1- VERY sensitive (results in 10 min)
2- No need to isolate the pathogen

Front 156

What are the 3 protein degradation reactions?

Back 156

deamination
desulfurylation
decarboxylation

Front 157

Deamination results in NH3--> NH4 + OH-. This causes what pH?

Back 157

alkaline

Front 158

An insoluble black precipitate of FeS is a result of what protein degradation reaction?

Back 158

Desulfurylation

Front 159

Triple Sugar Iron Medium is used to differentiate enteric bacteria based on 3 characteristics:

Back 159

1- ability to ferment sugar
2- produce H2S
3- produce gas

Front 160

TSI medium reaction:

alkaline slant and alkaline DEEP

What is the bacterial class based on the results?

Back 160

Non-fermentor

(break down of peptides on surface--> amines that sins down to the deep portion)

Front 161

TSI reaction:

Alkaline slant
Acid Deep

What is the bacterial class?

Back 161

NON-lactose fermentors

(glucose fermentation)

Front 162

TSI reaction:

Acid Slant
Acid Deep

What is the bacteria based on the reaction?

Back 162

Lactose/sucrose fermentors

Front 163

Alkaline reactions in TSI medium are due to:

Back 163

Peptides--> Amines

Front 164

Acid reactions in TSI medium are due to:

Back 164

Glucose fermentation

Front 165

What is an enterotube?

Back 165

Combination media: several compartments, each with a different substrate incorporated into the agar base.

Front 166

How does an enterotube combination media work?

Back 166

1- take cap off one end and innoculate needle
2- pull needle from opposite end
3- as needle drags through the length of the tube each compartment is innoculated

Front 167

Isolation of a homogeneous culture is required for all testing except ___, but this only works if antisera is available.

Back 167

Counterimmunoelectrophoresis

Front 168

What are the 3 types of physical sterilization?

Back 168

Temperature
Radiation
Mechanical

Front 169

Moist heat can be used to sterilize Mesophiles and psychrophiles. What is the appropriate temperature required to denature the proteins?

Back 169

>50C

Front 170

What is the Temperature and Time required for an autoclave to kill most bacteria?

Back 170

121C for 15 minutes

Front 171

Why would you want to autoclave a liquid?

Back 171

If a liquid is heat stable then it could be autoclaved and the steam would prevent evaporation.

Front 172

What is the appropriate time and temperature required for sterilization by Dry heat?

Back 172

160C (320F) for 1-2 hours

Front 173

Incineration requires temperatures greater than ____ and continues until the material is ____.

Back 173

300C

completely oxidized

Front 174

What is the critical wavelength of radiant energy that will have bacteriocidal effects?

Back 174

300nm

less than 300nm has a large bacteriocidal effect (shorter wavelength = higher energy)

greater than 300nm has little bacteriocidal effect

Front 175

Micowaves are greater than 300nm. How is it that they are bacteriocidal?

Back 175

The microwaves themself are not bacteriocidal, the heat they generate can be bacteriocidal, but it is more time consuming

Front 176

What 3 classes of rays are bacteriocidal?

Back 176

Gamma, UV, and x-rays.

Front 177

Ultraviolet radiation kills bacteria by causing :

Back 177

Thymine Dimers that distort the DNA molecule.

Front 178

What are the 2 types of ionizing radiation?

Back 178

X-rays, Gamma rays

Front 179

What method of sterilization causes the production of short lived oxygen and hydroxyl radicals?

Back 179

Ionizing radiation

Front 180

Ionizing radiation produces short lived radicals that do what?

Back 180

interact with macromolecules and cause disruption of COVALENT bonds

Front 181

What method of sterilzation can be used for inanimate, heat sensitive materials?

Back 181

Ionizing radiation

Front 182

What is the appropriate average pore size for effective liquid filtration?

Back 182

0.2 microns

Front 183

What does HEPA stand for in air filtration?

Back 183

High efficiency particulate air filter.

Front 184

What is the efficiency of a hepa filter: size and percentage?

Back 184

99.99% of 0.12 micron particles

Front 185

What is the purpose of sonication?

Back 185

remove organic material from the surface to ease disinfection via other methods.

Front 186

T/F: Sonication creates bubbles that bombard cells and LYSE them.

Back 186

True

Front 187

_____ refers to the elimination of pathogens by chemical means.

Back 187

Disinfection

Front 188

Physical sterilization includes temperature, radiation, ____, and ____.

Back 188

filtration
sonication

Front 189

Autoclaves sterilize efficiently due to the transfer of ______ from water to the object.

Back 189

latent heat

Front 190

What are the modes of action of Chemical agent disinfectants?

Back 190

1- alter permeability
2- irreversibly denature

Front 191

T/F: Gram positive bacteria are more susceptible to disinfectants than gram negative.

Back 191

True

Front 192

T/F: Gram Negative bacteria are less susceptible to disinfectants than acid fast bacteria.

Back 192

False: acid fast bacteria are less susceptible.

another way to put it: Gram negative bacteria are more susceptible to disinfectants than acid fast bacteria (think thick wall of acid fast bacteria)

Front 193

Why is a shorter time required to disinfect at higher temperatures?

Back 193

Temperature mediated interaction: means that increasing temperature increases interaction of molecules (specifically bacteria with the disinfectant molecules)

Front 194

There are 7 main classes of chemical disinfectants, Name 4.

Back 194

Alcohols
Alkalies
Heavy Metals
Oxidizing Agents
Alkylating agents
surface active agents
Phenolic compounds

Front 195

T/F: Pure alcohols are the stronges and most effective concentration of alcohol disinfectant.

Back 195

False: 100% alcohol is not effective at all as a disinfectant. Alcohol must be diluted with water in order for the denaturing process to occur.

Front 196

NaOH is an example of what class of chemical disinfectant?

Back 196

Alkalies

Front 197

How do alkalies work to disinfect? What can they be used on?

Back 197

Alkalies destroy cell walls and cell membranes.

Used on inanimate objects NOT sensitive to alkaline pH

Front 198

Mercuric Chloride and Silver Nitrate are heavy metal chemical disinfectants. They work by interfering with:

Back 198

cell transport

Front 199

T/F: disinfectant resistance is just as bad as antibiotic resistance.

Back 199

FALSE: very seldom is there resistance to a disinfectant.

Front 200

iodine and chlorine are halogens. What class of disinfectant are they?

Back 200

Oxidizing agents

Front 201

How do oxidizing agents work?

Back 201

conversion of --SH to --SS inactivates enzymes

Front 202

What is the cheapest and most effective disinfectant?

Back 202

Chlorine (bleach)

Front 203

Alkylating agents may be gaseous or liquid. Give an example of each.

Back 203

Formalin
glutaraldehyde

Ethylene oxide

Front 204

What does it mean to alkylate?

Back 204

addition of a hydroxyl, methyl or ethyl group or cross links

Front 205

What method of disinfection induces a reduction of surface or interfacial tension?

Back 205

Surface active agents

Front 206

There are two classes of surface active agent disinfectants. What are they and give an example of each?

Back 206

Anionic agents: soaps or fatty acids with a negative charge (sodium lauryl sulfate)

Cationic agents: quaternary ammonium compounds ( zephiran)

Front 207

what is the specific action of surface active agent?

Back 207

hydrophobiv portion of the chemical penetrates into the bacterial membrane and disrupts cell integrity--> the bacteria thus lose the ability to exist in its environment

Front 208

Phenol, Creosol, and hexacholrophene are examples of what class of chemical disinfectant?

Back 208

Phenolic compounds

Front 209

T/F: Phenolic compounds are often mixed with soap to increase penetration.

Back 209

True

Front 210

What is the chemical in "lysol"?

Back 210

creosol

Front 211

What are the 5 types of transmission of infectious agents?

Back 211

Veneral
Vertical
Contact
Ingestion
Inhalation

Front 212

What can majorly reduce the effectiveness of a disinfectant?

Back 212

Organic matter covering the pathogens....

ie: CRAP

Front 213

What are the 3 general mechanisms of gene transfer?

Back 213

Transformation,
Transduction
Conjugation

Front 214

T/F: Tranformation occurs in prokaryotes only.

Back 214

False: Tranformation occurs in prokaryotes AND eukaryotes.

Front 215

What does Phage mean?

Back 215

greek for: to eat

Front 216

You spread a bacteria on a plate. You then introduce a phage to the plate. The resultant clear area/dark circle represents what?

Back 216

bacterial growth that was lysed by the phage.

Front 217

Lysin:peptidoglycan hydrolase weakens the cell wall of bacteria. What does this look like microscopically?

Back 217

Membrane blebbing.

Front 218

In the lytic phase, a phage enters a cell and is packaged with host DNA, How does the phage get out?

Back 218

Virus recognizes peptidoglycan and lyses the bacterial cell wall from the inside out.

Front 219

What is the phase of transduction other than lytic? What causes it to become lytic?

Back 219

Lysogenic phase: Viral DNA recombines with Host DNA.

Lytic phase may be activated at a later point by many things (UV rays)

Front 220

How does Salmonella avoid recognition by the host immune system?

Back 220

Antigenic variation in the O antigen (LPS).

Front 221

What is an autonomously replicating extrachromosomal circular piece of DNA?

Back 221

Episome

Front 222

What does the term autonomously replicating indicate?

Back 222

Replication is independent of chromosomes

Front 223

What are the 3 basic types of episomes?

Back 223

F factor
R factor
Plasmids

Front 224

Episome F-factor is also known as____ factor.

Back 224

Fertility

Front 225

F-factor genes promote ___.

Back 225

replication and transfer of the F-factor to recipient cells

Front 226

R-factor is an F-factor plus ____.

Back 226

genes encoding resistance to specific antibiotics

Front 227

T/F: Plasmids are necessary for growth.

Back 227

False

Front 228

Plasmid genes may contain virulence factors whose origin is ___.

Back 228

unknown

Front 229

Episomes are transferred by ___.

Back 229

Conjugation

Front 230

Once an F+ episome is transferred what happens?

Back 230

The episome genes are recombined with the host DNA to yield a high frequency replication Hfr cell.

Front 231

R- factors contain 2 types of genes. What are they?

Back 231

F- factor and resistance

Front 232

R determinants may include genes encoding antibiotic resistance, heavy metal resistance, ___, or ____.

Back 232

insertion sequences, or other virulence factors

Front 233

What does RTF stand for? What does it encode?

Back 233

Resistance transfer factor

encodes origin of replication and sex pilin genes

Front 234

What is a transposon?

Back 234

Mobile genetic element that jumps from one region of a chromosome or episome

Front 235

How does Tn's jump?

Back 235

transposase binds to inverted repeat (IR) sites in element and mediates excision and insertion.

Front 236

What are the possible effects of Transposon movement?

Back 236

1- mutation/ malfunction
2- neutral event (insertion occured next to an intact gene)
3- excision/ movement of a neighboring gene (virulence transfer occurs this way)

Front 237

T/F: Transposons are mobile genetic elements that can mediate their own transfer as well as neighboring genes encoding toxins and antibiotic resistance.

Back 237

True

Front 238

who discovered that penicillum inhibited S. aureus in 1928?

Back 238

Alexander Fleming

Front 239

Who purified penicillin and showed that it worked in-VIVO?

Back 239

Chain and Florey in 1941

Front 240

Waksman did some work with Streptomyces in 1940. What did he discover?

Back 240

Streptomyces produced Streptomycin, effective at inhibiting bacterial growth in soil.

Front 241

Selective toxicity refers to antibiotic activity that:

Back 241

causes more harm to the pathogen than the host

* based on the AB abiltiy to recognize structure in the pathogen and not the host.

Front 242

What are the 2 main antimicrobial actions?

Back 242

Bacteriostatic
Bacteriocidal

Front 243

What antimicrobial action inhibits growth, but allows host defenses to kill or eliminate pathogen?

Back 243

Bacteriostatic

Front 244

What antimicrobial action kills the pathogen which is later removed by phagocytic activities?

Back 244

Bacteriocidal

Front 245

What is the drawback of Broad spectrum antibiotics?

Back 245

They also affect normal flora.

Front 246

Beta lactams, vancomycin, and bacitracin target ___.

Back 246

Cell wall

Front 247

What antibiotics target nucleic acid synthesis?

Back 247

Fluroquinolones, Rifamycins

Front 248

Aminoglycosides and tetracyclines target ___.

Back 248

Protein synthesis

Front 249

Macrolides and Chloramphenicol target ___.

Back 249

Protein synthesis

Front 250

How do antibiotics that target protein synthesis work?

Back 250

By binding to the ribosome--> prevents synthesis of Amino acids and protein packaging.

Front 251

Sufonamids and trimethroprim interfere with ___.

Back 251

Metabolic pathways/ folate synthesis.

Front 252

What antibiotics disrupt cell membrane integrity?

Back 252

polymyxin B
daptomycin

Front 253

T/F: peptidoglycan is found in prokaryotic and eukaryotic cells.

Back 253

False: peptidoglycan is unique to bacterial cells.

* this is how Ab cell wall inhibitors work (target peptidoglycan)

Front 254

Isoniazid inhibits _____ .

Back 254

Mycolic acid synthesis

*in mycobacterium

Front 255

gram negatives are less susceptible to Ab because their cell walls are stabilized by ___ and ___.

Back 255

Ca
Mg

Front 256

Gram negative bacteria may be made susceptible to Ab by _________.

Back 256

Chelating agents
* chelates Ca and Mg allowing Ab to penetrate the cell wall faster.

Front 257

______ can cause anemia by inhibiting protein synthesis in mitochondria associated with bone marrow.

Back 257

Tetracyclines

Front 258

Sulfonamides inhibit folate synthesis by competitive inhibition or ____.

Back 258

PABA

Front 259

Polymyxin B is limited to topical use because?

Back 259

It destroys the outermembrane integrity of eukaryotes as well as the prokaryote target.

Front 260

T/F: Daptomycin is more effective on gram positives.

Back 260

True

* daptomycin cannot penetrate the outer membrane of gram negatives in order to bind to the cytoplasmic membrane (causes K+ leakage)

Front 261

Fluoroquinolones bind to ____

Back 261

DNA gyrase

Front 262

Rifamycin bindes to _____.

Back 262

RNA polymerase --> inhibits RNA transcription

Front 263

What is the difference between intrinsic resistance and acquired resistance?

Back 263

Intrinsic resistance: bacterium lack target site or transport mechanism for uptake

Acquired resistance: mutation, acquisition of resistant chromosomal DNA

Front 264

The majority of Antibiotics originate in the soil bacterium, ____.

Back 264

Streptomyces

Front 265

What are 5 different types of vaccines?

Back 265

killed
live
live recombinant
dna
subunit

Front 266

what type of vaccine contains the gene for antigen expressed in a microbe?

Back 266

live recombinant

Front 267

what type of vaccine does the gene encoding antigen express directly in the immunized host?

Back 267

DNA vaccine

Front 268

What is the risk of live vaccines?

Back 268

reversion of the pathogen to disease causing status

Front 269

What is the drawback of killed vaccines?

Back 269

not very effective

Front 270

Which vaccine type is expensive due to the requirement for a good adjuvant?

Back 270

Subunit vaccine

Front 271

Which vaccine type faces more regulatory hurdles?

Back 271

Live recombinant

Front 272

What is the current scientific dilemma with DNA vaccines?

Back 272

Gene silencing by host.

Front 273

T/F: you can attenuate a bacterial pathogen by knocking out a single gene.

Back 273

True

Front 274

What is the purpose of mutation methodology in vaccine technology?

Back 274

1- determine whether a gene is a virulence factor (required for infection)
2- create mutants for vaccines (live attenuated, etc)

Front 275

Transposons can be used to define virulence factors. How?

Back 275

Tns are genetic elements tha can randomly insert into bacterial chromosomes. If as a result of Tn insertion the bacterai cannot infect, then the interrupted gene would be a virulence factor.

Front 276

Cloning of antigenic genes and moving them into high copy # plasmids under control of a promoter results in ___.

Back 276

over-expression of genes

*useful for antigenic purificaiton

Front 277

Affinity Chromotography is used to ____.

Back 277

Separate proteins

Front 278

Exposing Vaccine antigens to SOD would increase virulence,(increasing/decreasing) the required effective dose.

Back 278

decreasing

*more virulence= more antigenic so less is required to stimulate a response

Front 279

How long does it genearlly take to diagnose unknown bacteria in the clinic?

Back 279

2-3 days

sample
smear
innoculate
incubate
stain
innoculate on differential media
incubate
read differential results
ID

Front 280

Advantages of DNA based test?

Back 280

high sensitivity (a single organism)
high specificity (specific genotypes)
faster

Front 281

The high sensitivity of DNA based testing allows for growth of organims that are:

Back 281

low numbers
unisolatable
fastidious

Front 282

Why would DNA based testing be prefered for highly infectious or zoonotic diseases?

Back 282

very low numbers can be used to ID the organism minimizing exposure and risk during handling.

*if it requires 30 organims to cause disease then 15 could be used instead (highly sensitive)

Front 283

What are the disadvantages of DNA based testing?

Back 283

EXPENSIVE
high specificity requires knowledge of organism present (must know what your testing for)

Front 284

PCR is used to _____ template DNA.

Back 284

exponentially amplify

Front 285

Advantages of Real-Time Polymerase Chain Reactions:

Back 285

1- extremely fast (10-20 min)
2- can multiplex the analyses by using multiple fluorescent signals
3- can be automated to handle large sample nubmers

Front 286

Brucella causes ____ in livestock

Back 286

abortion in livestock

Front 287

what is the gram stain and microstructure of Brucella?

Back 287

Gram negative
Cocco-bacillus

Front 288

T/F: An RB51 vaccine should be given to a cow during late pregnancy to induce Ab production in colostrum (for neonate protection).

Back 288

False:

RB51 given to a pregnant cow can cause abortion.

Front 289

T/F: PCR provides rapid confirmation of presence of the causative agent.

Back 289

True

Front 290

Sensitivity, specificity, and speed are advantages of what particular technology?

Back 290

PCR

Front 291

______ allows for vaccine enhancement by over-expression of genese, targeted gene mutations, creation of DNA vaccines.

Back 291

Recombinant DNA

Front 292

Which staphylococcus species is always coagulase negative?

Back 292

S. epidermidis

Front 293

S. hyicus is a common pathogen that causes exudative dermatitis and arthrisis in what animal?

Back 293

Pigs

Front 294

This species of staph is the leading pus forming bacteria in DOGS.

Back 294

S. intermedius

Front 295

Gram positive cocci occurring in small clumps or clusters in a liquid media.

Back 295

Staphylococci

Front 296

2 staph species of major importance in veterinary medicine:

Back 296

S. aureus
S. intermedius

Front 297

How do you differentiate between pathogenic and non-pathogenic speces of staphs?

Back 297

Pathogenic species are coagulase positive (S. aureus, S. intermedius)

Nonpathogenic species are generally coagulase negative (S. epidermidis)

Front 298

Where are Staphs found?

Back 298

mucocutaneous borders:
skin, external nares, perineum, udder, genitalia

Front 299

What is the predominant Staph of Dogs?

Back 299

S. intermedius

Front 300

Staphylococcus hyicus is found on the skin of ___ and ___.

Back 300

Pigs and poultry

Front 301

T/F: Staphs are not viable in the environment.

Back 301

False.

* Staphs are stabile in soil, air, dust, water.... Streps are not.

Front 302

How are most staph infections transmitted?

Back 302

Endogenous

Front 303

There are many Virulence factors associated with Staphs. Name 4:

Back 303

Intracellular survival
Coagulase (questionable)
Capsule/ Pseudocapsule
Peptidoglycan/ Teichoic Acids
Urease
Exotoxins

Front 304

_____ is a virulence factor associated with chronic/ recurrent infections

Back 304

Intracellular survival

Front 305

T/F: Pathogenic strains of staph tend to be coagulase positive.

Back 305

True

Front 306

____ is present on ALL pathogenic Staphs. It has antiphagocytic properties.

Back 306

Capsule/ Pseudocapsule

Front 307

Teichoic acids are found in staphs and function specifically to:

Back 307

Adhere gram positive bacteria to the mucosal surface.

Front 308

What virulence factor is involved in the pathogenesis of uroliths/ cystitis?

Back 308

Urease- converts urea to ammonia raising the pH of the environment in the bladder/ urine.

Front 309

T/F: exotoxins are relased by bacteria as a result of cell wall breakdown after cell death.

Back 309

False.

Endotoxins do this.
Exotoxins are actively secreted to lyse inflammatory defense cells in order to avoid death.

Front 310

alpha hemolysin of staphs produces a _____ zone of hemolysis

Back 310

CLEAR
Complete hemolysis

Front 311

beta hemolysin of staphs produces a _____ zone of hemolysis

Back 311

PARTIAL

Front 312

_____ hemolysin of staphs and streps does not produce any hemolysis.

Back 312

Gamma

Front 313

Why are Staphs, which are part of the normal flora, cosidered highly pathogenic?

Back 313

They are opportunistic, but require very few numbers and little host compromise to cause an infection.

Front 314

What are the clinical implications of an opportunistic infection like staph?

Back 314

Must find the underlying causes for the breakdown in host defenses or the infection will recur.

Front 315

what is the predominant pattern of staph infections?

Back 315

suppuration and abscess formation

Front 316

a pus filled abscess in the intervertebral space would cause_____

Back 316

discospondylitis

Front 317

What is the morphology/composition of an abscess?

Back 317

pus = mixture of host cell debris and bacteria (living and dead)

surrounded by intact leukocytes and fibrin strands

Front 318

Exudative dermatitis and tick pyaemia are the only clinical conditions of domestic animals SPECIFICALLY attributable to pathogenic ____.

Back 318

staphylococci

Front 319

what are the classes of mastitis?

Back 319

subclinical
acute suppurative
gangrenous
chronic

Front 320

Why is mastitis so difficult to treat?

Back 320

bacteria are located intracellularly

Front 321

What class of mastitis causes the udder to become cold, blue, and slough?

Back 321

gangrenous

Front 322

What causes tissue necrosis in gangrenous mastitis?

Back 322

alpha toxin-- causes contraction and necrosis of smooth muscle in blood vessel walls, impeding blood flow

Front 323

what is the chief bacteria associated with canine pyoderma?

Back 323

S. intermedius

Front 324

What disease does staph cause in gallinaceous birds?

Back 324

Bumble foot

Front 325

What is Botyomycosis?

Back 325

staph infx causing suppurative, granulomatous lesions, esp in udders as well as EQUINE SPERMATIC CORD

Front 326

Greasy Pig Disease affects youung pigs... results in thick grayish brown exudate.

What is the other name for this disease and what bacteria causes it?

Back 326

Exudative epidermititis

S. hyicus

Front 327

T/F: Greasy Pig is not contagious.

Back 327

False.

It is highly contagious

Front 328

Tick Pyemia is a disease affecting what species in what region?

Back 328

Lambs in Britain and Ireland

Front 329

Coagulase Negative Staphs can cause infection under what conditions?

Back 329

immunocompromised, compromised sites, nonsocomial infections

* think s. epidermidis.

Front 330

Diagnosis of staph infections is highly dependent on ____, because they are easily contaminated by normal flora.

Back 330

Good sample collections

Front 331

What cells MUST be present in order to ascribe any significance to the bacteria that has been isolated?

Back 331

Inflammatory cells-- primarily PMNs

Front 332

What is the best agar and environment to culture staphs?

Back 332

Blood

aerobic

Front 333

What is pollakiuria?

Back 333

pain on urination

Front 334

_____ is important for clearance of staphs from an infected site.

Back 334

Complement opsonization/ phagocytosis

Front 335

T/F: recovery from staph infection confers lasting resistance.

Back 335

False: there is no lasting resistance, and reinfection is possible.

Front 336

What is an important step in treatment of staph infections that have abscessed?

Back 336

drain the abscess... antibiotics penetrate poorly into pus

Front 337

S. aureus has ______ sensitivity pattern. What it the clinical implication of this characteristic?

Back 337

unpredictable

It may or may not be resistant to a variety of antibiotics... so antibiotic susceptibiltiy testing should be performed

Front 338

T/F: Sensitivity testing should always be performed on coagulase negative staphs.

Back 338

False: coagulase negative staphs are not of clinical significance in most cases

* except for s. epidermidis (implant infections)

Front 339

Why might antimicrobial therapy be ineffective for streps?

Back 339

Staphs can survive intracellularly

Front 340

What Strep causes Strangles?

Back 340

Strep equi

Front 341

What strep is involved in often the cause of chronic mastitis?

Back 341

S. agalactiae

Front 342

Alpha hemolytic streps cause ____ hemolysis patterns.

Back 342

Partial-- green

Front 343

Beta hemolytic streps cause ____ hemolysis patterns.

Back 343

completely clear

Front 344

Gram + cocci that form chains

Back 344

Streptococci

Front 345

How can culture age affect a gram stain?

Back 345

older cultures (Gram +) may stain gram negatively

* exudates may have the same effect

Front 346

Why do Streps form chains?

Back 346

they divide in one plane to form pairs which overtime results in chains

Front 347

What is the environmental preference of streps?

Back 347

Facultative anaerobe

*some grow better in CO2

Front 348

Staphs that are not part of the normal flora can still persist by means of _____, which means they are obligate parasites.

Back 348

carriers

Front 349

T/F: Strep infections may be acquired endogenously or exogenously.

Back 349

True

Front 350

Contagious Streps include:

Back 350

Str. equi
Str. agalactiae

Front 351

What are the primary virulence factors associated with Streps?

Back 351

M proteins
Capsule
Hemolysins

Front 352

which hemolytic class of streps is more pathogenic?

Back 352

beta

Front 353

which hemolytic class of streps is has more widespread antibiotic resistance?

Back 353

alpha

Front 354

What enzyme is responsible for the the complete hemolysis reaction of beta hemolytic streps?

Back 354

Streptolysin

Front 355

beta hemolytic streps are predictably sensitive to what antibiotic?

Back 355

Penicillin

Front 356

What are the 3 main pus producing bacteria?

Back 356

Staphs
Streps
Corynebacterium

Front 357

Why are strep infections Acute?

Back 357

They have no intracellular survivability and are cleared with Antibody production

Front 358

What virulence factor allows streps to inhibit phagocytosis and ahere to epithelial cells?

Back 358

M protein--

Front 359

Anti-M protein antibodies are associated with protection and there for the basis for strep prevention via ____.

Back 359

Vaccines

Front 360

If the Strep infection is resistant to Antibodies produced _____ hypersensitivity may result.

Back 360

Type III

Front 361

Most of the streps in abscesses will Stain Gram ___.

Back 361

negative

* Exudate and age alters the stain

Front 362

Give an example of cervical lymphadenitis:

Back 362

Strangles
Jowl Abscess

Front 363

Incubation period of Strangles?

Back 363

3-6 days

Front 364

where is str equi carried in carriers of strangles?

Back 364

Guttural pouch

Front 365

The course of uncomplicated cases of strangles is how long:

Back 365

5-10 days

* at this point the abscesses will rupture releasing purulent, infx material

Front 366

What are some of the complications associated with Strangles?

Back 366

dissemination (bastard strangles)
guttural pouch empyema
purpura hemorrhagica
death due to asphxiation

Front 367

What is the critical location of sterility in the respiratory tract?

Back 367

Sterile AFTER the larynx

Front 368

Str. zooepidemicus is one of the most common causes of uncomplicated bacterial ____ in horses.

Back 368

pneumonia

Front 369

S. agalactiae, S. dysgalactiae, and S. uberis are the leading agents of ______ in what species?

Back 369

bovine mastitis

Front 370

What is the most common cause of mastitis in the DRY period?

Back 370

S. uberis

Front 371

What is the layman's term for Necrotising Fasiculitis>?

Back 371

Flesh eating bacteria

* S. aureus, St. pyogenes, C. perfringens...

Front 372

What do streps need in order to grow?

Back 372

blood, SERUM, or a fermentable sugar

Front 373

What is the catalase reaction of Streps?

Back 373

NEGAtive

Front 374

The hosts main defense against streps is ____.

Back 374

Phagocytosis

Front 375

T/F: Immunity usually develops following a strep mastitis in the cow.

Back 375

False: no useful immunity develops and cows remain infected unless treated

Front 376

beta hemolytic streptococci are predictively sensitive to what antibiotic?

Back 376

penicillin

Front 377

_____ are frequently resistant to aminogycosides, fluoroquinolones and tetracyclines.

Back 377

Streptococci

Front 378

What is a VRE?

Back 378

vancomycin resistant enterococci

alpha hemolytic streps are more resistant to antibiotic therapy

Front 379

T/F:Horses with developing abscesses (strangles) should be given penicillin to prevent the abscess from getting worse.

Back 379

False: these abscesses should be encouraged to mature and lyse

Front 380

streps are notably more fragile than staphs. how long can Strangles survive in dry connditions?

Back 380

weeks to months in dry dusty conditions

Front 381

horses can carry Str equi in their guttural pouch for up to ____.

Back 381

6 weeks

Front 382

What is the morphology of Enterococci?

Back 382

Gram positive Cocci

Identical to Streptococci

Front 383

Enterococci used to be classified under Streptococci, but ehy have recently gained their own genus due to their growing importance as dz causing agents. Why are they all of the sudden becoming so popular?

Back 383

Second most common cause of Nonsocomial infections in the USA

ANTIBIOTIC RESISTANCE

Front 384

Micrococci are gram positive cocci morphologically similar to ___.

Back 384

Staphylococci

Front 385

What can be said about the pathogenicity of Micrococci?

Back 385

They are NEVER pathogenic

Front 386

What gram positive Cocci are STRICT ANAEROBES?

Back 386

Peptococcus and Peptostreptococcus

Front 387

What are the gram positive rods we have studied?

Back 387

Bacillus and Clostridium

Front 388

You do a culture and then a stain a smear of an isolate from the plate. The result is gram (-) cocci. What is the differential diagnosis?

Back 388

There is no diagnosis. You fucked up the stain. There are NO gram (-) cocci.

Front 389

What type of pathogen is Bacillus anthracis?

Back 389

Obligate

Front 390

What is the morphology of B. anthracis?

Back 390

gram +
blunt ended rods
spore forming

Front 391

T/F: There are only TWO spore-forming GRAM + rods.

Back 391

True: bacillus and clostridium

Front 392

How do you differentiate Clostridium from Bacillus?

Back 392

Clostridium will only grow anaerobically while Bacillus will grow aerobically

*Bacillus sp. are catalase positive
Clostridia are not

Front 393

B. anthracis has a ____ (structure) that ONLY forms in vivo.

Back 393

Capsule

Front 394

B. anthracis is found in ____ where it survives as _____.

Back 394

Soil

Spores

Front 395

B. anthracis prefers soil that has an ___ pH rich in Calcium and Nitrate.

Back 395

Alkaline

Front 396

How do people get anthrax from sheep?

Back 396

Wool Sorter's disease

Fleeces can harbor anthrax spores

Front 397

T/F: Anthrax outbreaks do not usually occur in North America, but if they do it generally occurs in areas that are Dry and have sporadic heavy rain.

Back 397

True

Front 398

B. anthracis is only found in endemic areas, but other Bacillus species are commonly found in____

Back 398

soil, air, dust, water---> makes them common lab contaminants

Front 399

What causes germination of B. anthracis spores?

Back 399

High Temperatures, Most conditions, lack of other competing soil bacteria.

Front 400

What are the 4 modes of transmission of anthrax?

Back 400

1- ingestion
2- wounds
3- mechanical- vector
4- inhalation

Front 401

what are the 2 major virulence factors of B. anthracis?

Back 401

capsule

exotixin

Front 402

Anthrax exotoxin consists of 3 protein components (i, ii, iii). What are they?

Back 402

i- Edema Factor
ii- Protective Antigen

(Both of these produce EDEMA)


iii- Lethal Factor

Front 403

What is the job of Protective Antigen?

Back 403

Allows Edema Factor and Lethal Factor to enter the cell

Front 404

Edema Factor is an ______ activated by host cell calmodulin, causing an increase in CAMP and a subsequent secretion of Cl- and HCO3-, preventing absorbtion of Na+ and Cl-.

Back 404

adenylate cyclase

Front 405

____ factor causes a mass increase in IL-1 that causes an increase in vascular permeability.

Back 405

Lethal

Front 406

What animal species is most susceptible to anthrax?

Back 406

Cattle

and humans

Front 407

Blood from the orifices, failure to clot, and absence of rigor mortis are associated with what disease?

Back 407

Acute death by Anthrax

Front 408

Pigs, dogs, and cats are highly resistant to anthrax infections, but if they are infected they are very sensitive to the toxins. Particularly _____ toxin.

Back 408

Edema Factor

Front 409

What is the treatment for Anthrax?

Back 409

Penicillin

Front 410

What is the common culprit of gangrenous mastitis?

Back 410

B. cereus

* can cause a superinfection due to the widespread resistance to common antibiotics

Front 411

How can you diagnose anthrax in a dead cow?

Back 411

get a blood sample from the ear vein or aqueous humor from the eye, do a smear stain

Front 412

T/F: Spore production for B.anthracis does not occur in vivo.

Back 412

True: spores only form after the carcass is exposed to air.

Front 413

T/F: diagnosis of anthrax is frequently made on the results of blood smears.

Back 413

True

* care must be taken to differentiate from post-mortem invaders

Front 414

T/F: All species of Bacillus except for B. anthracis are sensitive to antibiotics

Back 414

False... other way around.

b. anthracis is susceptible to penicillin... other speicies are not predictably sensitive.

Front 415

What are the disposal recommendations for an anthrax case?

Back 415

incineration

buried --> >6.5feet deep + 6" quick lime

Front 416

What is a malignant carbuncle?

Back 416

cutaneous anthrax--> reported in humans

Front 417

What genus of bacteria is this?

Gram +
Spore forming Rods
Strict Anaerobes
Motile
gas producing

Back 417

Clostridium

Front 418

Since Clostridia are strict anaerobes, what is required in an infection before the spores can germinate?

Back 418

Necrosis

Front 419

Clostridia produce 3 major types of disease:

Back 419

histotoxic
enterotoxic
neurotoxic

Front 420

All clostridia are sensitive to ____.

Back 420

Penicillin

Front 421

Clostridia are found in the environment where?

Back 421

Soil

Freshwater
Marine sediment

Front 422

Clinical signs of clostridia infection are dependent on the type of ____ that a particular strain produces.

Back 422

Exotoxin

Front 423

Name 3 major Clostridial diseases.

Back 423

Botulism
Tetanus
Malignant edema
Black leg
Black disease
Enterotoxemia
enteritis/dysentery

Front 424

____ toxin is one of the most powerful biological toxins known.

Back 424

Botulism

Front 425

T/F: not all types of botulinum toxin produce intoxication in all animal species.

Back 425

True

Front 426

Why shouldn't babies eat honey?

Back 426

May contain Botulinum spores.

Front 427

____ (animal) are VERY resistant to botulinum toxin. Disease is RARE.

Back 427

DOMESTIC Cats

Pigs too.

Front 428

Transmission of C. botulinum toxins occurs most commonly via ___.

Back 428

Food poisoning/ Forage

Front 429

Shaker foal syndrome is a result of what mode of Botulinum toxin transmission?

Back 429

Toxicoinfectious

ingestion of spores--> colonize GIT---> protoxin, activated by proteases---> toxins absorbed into systemic circulation

Front 430

Where do the botulinum toxins bind to produce neurologic effects?

Back 430

Neuromuscular junctions
nerve-nerve junctions

Front 431

neuromuscular blockade associated with botulism results in ______, where _____ is the usual cause of death.

Back 431

FLACCID paralysis

Respiratory failure

Front 432

T/F: The botulinum toxin binds irreversibly to the nerve receptors.

Back 432

True: the only way to regenerate lost function is to create new neuromuscular junctions

(ie: why botox has to be repeated)

Front 433

Botulinum toxin acts presynaptically to block ___ release

Back 433

acetylcholine

Front 434

what does a bird with botulism looks like?

Back 434

limber neck: walking around with their head/neck dragging the ground

Front 435

in Botulism there is acending flaccid paralysis, dysphagia and decreased ____ tone.

Back 435

tongue

Front 436

there are NO significant findings on blood chem, rads, or post mortems of animals with Clostridia infection, but diagnosis can be made fairly easy via:

Back 436

ELISA or PCR

Front 437

How do you treat Botulism?

Back 437

antitoxin
supportive therapy
antibiotics (maybe not)

Front 438

T/F: A classic Tetanus case will generally have a fever.

Back 438

FALSE:
Tetanus is Afebrile

Front 439

C. tetani are found mostly in what environment?

Back 439

Soil (manure)

Front 440

T/F: antitoxin from any of the 10 antigenic types of clostridium tetani may be used effectively against any one antigenic type

Back 440

True

Front 441

Why are puncture wounds prone to develop tetanus?

Back 441

if they are deep or reseal then they create a lovely anaerobic environment that allows sporulation to occur

Front 442

C. tetani produces 2 toxic substances:

Back 442

hemolysin--> tetanolysin
lethal toxin--> tetanospasmin

Front 443

T/F: tetanus acts specifically on the excitatory synapses, stimulating constant contractions.

Back 443

False: tetanus neurotoxin acts specifically on the INHIBITORY synapses, preventing release of glycine and gaba from the inihibitory interneuros..

lack of inhibitions= overexcitation

Front 444

Like Botulinum toxin, tetanus toxin binding is irreversible. In this case recovery is dependent on the produciton of new ____.

Back 444

axon terminals

Front 445

What species are highly susceptible to tetanus toxin?

Back 445

Horses, mice, guinea pigs, rabbits, monkeys, humans

Front 446

What is one of the first clinical signs that may be observed in tetanus toxic animals?

Back 446

Protrusion of the nicitating membrane oacross the eye

Front 447

tetany of the masseter muscle is called:

Back 447

lockjaw

Front 448

convulsive contraction of voluntary muscles in tetany results in ____ rigidity and a saw horse stance.

Back 448

extensor

Front 449

tetanus is often localized in what species

Back 449

dogs and cats

Front 450

T/F: Diagnosis of Tetanus is usually on clinical grounds alone.

Back 450

True

*isolation of the organism is difficult even when the location of the wound is known

Front 451

Fortunately Tetanus is not as common in the united states. Why?

Back 451

Vaccinations

Front 452

T/F: If you can stop the contractions, tetany can be ridden out until the toxin wears off.

Back 452

True:

diazepam and ace promazine = muscle relaxant

Front 453

What does antitoxin do?

Back 453

binds to unbound toxin in an animal that is already clinically affected

Front 454

TOXOID is used for vaccines. What is it?

Back 454

Modified toxin

Front 455

you do a fine needle aspirate of an infected site on a horse. You stain it and get gram positive rods that are forming spores. What is your immediate diagnosis or do you need to culture it?

Back 455

Clostridiaaaaaa!

*No need to culture...clostridia are the only g+ Rod that produces spores IN VIVO

Front 456

Any organ/ tissue may be involved in histotoxic disease, but the main 4 tissues are:

Back 456

Muscle
Liver
Udder
Intestine

Front 457

Anaerobic cellulitis, gas gangrene, black leg, black disease, big head, and bacillary hemoglobinuria are all what type of diseases?

Back 457

HISTOTOXIC

Front 458

Clostridial diseases MUST have the opportunity to _____ anaerobically.

Back 458

multiply

Front 459

Anaerobic cellulitis is a less aggressive form of _____.

Back 459

Myonecrosis/ gas gangrene

Front 460

Gas production is associated with what clostridial disease?.

Back 460

Myonecrosis
Malignant Edema
Gas Gangrene

(all the same thing)

Front 461

symptoms: crepitous swelling over hindquarters, clack muscle, gas bubbles... in a young well fed cow

Back 461

BLACK leg

Front 462

T/F: big head disease results from goat egos clashing.

Back 462

True: head butting causes them to get a boo-boo and thus clostridium gains entry into their stupid little heads and Voila: edema of the head neck and cranial thorax

Front 463

Black disease is also called Infectous Necrotic Hepatitis and it is caused by

Back 463

C. novyi type B

Front 464

NAME that Disease!

wandering parasites bring Clostridia in from the intestine to the liver and cause necrotic lesions that allow for germination/multiplication of clostridia and the release of toxins into circulation=== congestion and heart damage

Back 464

Black disease

Front 465

Treatment and control of clostridial tetanus disease include 4 main points:

Back 465

debridement
O2 therapy
antibiotics (penicillin)
antitoxin

Front 466

Pulpy Kidney aka Enterotoxemia is a problem with feedlot lambs fed rich rations of grains. Why?

Back 466

Over eating disease--> gut stasis--> allows GI flora to move about the system (as oppposed to being constantly moved toward the exit)

Front 467

Classic sign of enterotoxemia:

Back 467

DROP DEAD

Front 468

What is the normal location of C. perfringens in the animal? Where is it once enterotoxemia occurs?

Back 468

Large intestine

Small intestine (badness)

Front 469

T/F: Enterotoxemia is a "true toxemia" with little enteritis.

Back 469

True

Front 470

This clostridial disease causes cellular necrosis in the brain, vascular endothelial cells, renal cortex.... and perivascular edema in the meninges and the brain.

Back 470

Enterotoxemia

Front 471

Epsilon protoxin is released and activated by trypsin and chymotrypsin in the pathogenesis of what disease?

Back 471

Enterotoxemia

Front 472

What kind of vaccine is used to combat enterotoxemia?

Back 472

TOXOID

* duration is short-lived
ewes are vaccinated before lambing and then lambs are vaccinated at 2 mo and 4 mo

Front 473

farmer Crankneista calls you up all worried about his most beloved ram. His ram is sick: roaming around, not eating, and standing with his head against the barn. Whats wrong with Crankneista's ram?

Back 473

Crankneista has fed his rammie TOO much GRAIN and has caused gut stasis resulting in Enterotoxemia.

Bad Crankneista.

Front 474

What is a sialocoele?

Back 474

Salivary Gland Cyst

Front 475

What antibiotic will NOT be effective treatment for enterotoxemic clostridial disease?

Back 475

tetracycline

* clostridia are naturally resistant (not due to development of antibiotic resistance

Front 476

How do you diagnosis enterotoxemia?

Back 476

detection of the bacteria in the feces by immunoassay.

Front 477

What does Pathonomonic mean?

Back 477

A pathognomonic sign is a particular sign whose presence means beyond any doubt, that a particular disease is presen

Front 478

What do the Mucous membranes of a toxemic animal look like?

Back 478

dark, dry

Front 479

Dysentery and Enteritis is most commonly seen in what age group?

Back 479

Young

*but can occur in adults

Front 480

What clostridia species causes enteritis other than C. perfringens?

Back 480

C. difficile

* esp in horses

Front 481

What are 3 diseases that can be caused by C. perfringens?

Back 481

Malignant Edema (Gas Gangrene)
Enterotoxemia
Enteritis