Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
181 Cards in this Set
- Front
- Back
|
Gram Neg Staining
|
lipid layer is dissolved using decolorizer which leaches the primary dye
|
|
|
Gram Pos Staining
|
decolorizer dehydrates bacteria and the wall shrinks, retaining color
|
|
|
gram staining
|
based on ability of cell wall to retain crystal violet treatment
|
|
|
safranin red
|
counter stain, gives gram neg. bacteria color
|
|
|
coccus
|
round
|
|
|
bacills
|
rod
|
|
|
strepto
|
chains
|
|
|
staphylo
|
cluster
|
|
|
flagella
|
H-antigens, composed of flagellin, evade phagocytosis, immunogenic
|
|
|
long conjucation pili
|
f or sex pili, produced by bacteria w/ f-plasmid. RAPID SPREAD OF ANTIBIOTIC RESISTANT GENES
|
|
|
short attachment pili
|
aka fimbriae, promote adhesion to human cells, result in blod clot formation, hemagglutination
|
|
|
Capsule
|
k-antigen, prevents phagocytosis, hydrophobic arrier, polysaccharide
|
|
|
pili
|
mostly gram neg bacteria
|
|
|
Gram Pos
|
Thick peptidoglycan, teichoic acid, lipoteichoic acid, complex polysaccharides, no outer envelope
|
|
|
Gram Neg
|
thin peptidoglycan, no techoic acids or complex polysaccharides, outer membrane present
|
|
|
acid-fast bacteria
|
presence mycolic acids forms a waxy layer resistant to stain, resistant to environ, insults, look pink
|
|
|
weak staining bacteria
|
legionella
|
|
|
thin cell walled-bacteria
|
treponema and leptospira
|
|
|
no cell walled-bacteria
|
mycoplasma
|
|
|
Peptidoglycan backbone
|
n-acteyl glucosamine and n-acetyl muramic acid linked by beta 1,4
|
|
|
lysozyme
|
degrate beta 1,4 linkages in peptidoglycan backbone
|
|
|
transpeptidase
|
catalyzes cross-linking of peptide chains in peptidoglycan, PBP
|
|
|
carboxypeptidases
|
remove unreacted d-alanines to limit crosslinking of peptidoglycan, PBP
|
|
|
Virulence of Peptidoglycan
|
Muramyldipeptide (NAM +2aa) is adjuvant, pyrogen (fever) somnogen (sleep) and blocks macrophages
|
|
|
Teichoic Acids and virulence
|
surface antigens, limit autolysis to promote growth, addherence, techoic acid in blood induces shock, fever
|
|
|
lipoteichoic acid and virulence
|
dermal necrosis (schwartzmans rxn), cell mitosis, adhesion, complement, anaphylaxis
|
|
|
polysaccharides and virulence
|
polysaccharides linked to the peptidoglycan cause inflammatory arthritic joint disease, granulomatous liver disease, hemopoetic stem cell production, Crohn's disease
|
|
|
Periplasmic space
|
between cytoplasmic membrane and outer membrane, contains peptidoglycan and enzymes
|
|
|
LPS
|
O-antigen, core, lipid A
|
|
|
Cell envelope and virulence
|
barrier to enviro. conditions, prevents antibiotics, absorption for bacteriophages,
|
|
|
LPS and virulence
|
O antigen induces immune response, lipid A induces IL1-> fever, blood clotting, shock, TNF- clotting and necrosis
|
|
|
Endospore
|
ONLY gram positive, high conc. of calcium bound to dipicolinic acid, most resistant life forms
|
|
|
spore forming bacteria
|
bacillus anthracis, acillus cereus, clostridium botulinm, clostridium perfringens, clostridium tetani
|
|
|
binary fission
|
segregation of chromosomes, septum formation, cell division-
|
|
|
Growth curve
|
log of turidity versus time
|
|
|
Lag phase
|
initial pd of adaptation, accumulate metabolites, suceptibility to phys/chem agents
|
|
|
Log phase
|
bacteria multiply rapidly, double at constant rate, susceptible to certain antibiotics- beta lactams
|
|
|
generation time
|
time required for bacterial mass to double, longer is advantageous, g=t/n
|
|
|
stationary phase
|
induction of immune response, dcreased growth rate but no death yet, spores form here, less susceptible to antibiotics
|
|
|
death phase
|
decrease in number of live bacteria
|
|
|
Phototroph
|
use light as main source of energy
|
|
|
chemotroph
|
use redox of chem. compounds as energy
|
|
|
autotroph
|
require inorganic chemiclas (CO2) for carbon source to synthesize organic molecules
|
|
|
heterotroph
|
utilize organic form of carbon for growth
|
|
|
chemoheterotrophs
|
most pathogenic bacteria- use organic compounds as both their energy and carbon source
|
|
|
enriched media
|
allow nonselective grown of any bacteria in a sample, sterile body fluids
|
|
|
selective media
|
only permit certain growth, for samples where there is a lot of bacteria-> stool, sputum, ex- macconkey
|
|
|
siderophores
|
sequster available iron for cytochromes- necessary for energy of bacteria
|
|
|
obligate aerobes
|
aerobic respiration, contain superoxide dismutase and catalase
|
|
|
facultative anaerobes
|
aerobic untill O2 runs out, contain superoxide dismutase and catalase
|
|
|
obligate anaerobe
|
anaerobic respiration, no catalse or superoxide dismutase
|
|
|
mesophiles
|
bacteria that grow at body temp- all human pathogens and opportunists
|
|
|
psychrophiles
|
bacteria that grow at freezing temps
|
|
|
thermophiles
|
bacteria that grow at boilng temps
|
|
|
aerobic respiration
|
uses O2 as terminal electrion receptor, glycolysis, TCA cycle and ETS, NAD is converted to NADH, ATP and water produced
|
|
|
anaerobic respiration
|
used other inorganic compoud as final electron receptor- for facultative anaerobes and anaerobes
|
|
|
fermentation
|
fermentable substrate like sugars yeild reducible intermediates like lactic acid, absense of oxygen
|
|
|
Targets of antimicrobials
|
protein synthesis, cell wall synthesis, cell membrane synthesis, and ncleic acid synthesis
|
|
|
sulfonamides
|
prevent PABA incorporation into folic acid, used with trimethoprim to inhibit nucleic acid synthesis in bacteria
|
|
|
trimethoprim
|
inhibits dihydrofolate reductase - used along with sulfonamides to inhibit nucleic acid synthesis in bacteria
|
|
|
Quinolones
|
inhibit DNA gyrase and topoisomerase- inhibit bacteria DNA replication
|
|
|
Metronidazole
|
fragments bacterial DNA which inhibits replication
|
|
|
Rifampicin
|
binds to RNA-Pol to inhibit RNA synthesis
|
|
|
Tetracyclines
|
bind to A site to prevent protein synthesis in bacteria
|
|
|
Aminoglycosides
|
bind to small subunit of ribosome and also cause misreading of mRNA
|
|
|
Macrolides
|
bind to large subunit of ribosome and inhibit bacterial protein synth
|
|
|
cholarmpnicol lincomycin, chlindamycin
|
bind to lg subunit, inhibit peptidyl transferase activity in protein synth of bacteria
|
|
|
bactroprenol
|
carrier of NAM and NAG in the cell membrane of peptidoglycan for cell wall synth
|
|
|
Cycloserine
|
inhibits cell wall synthesis by blocking addition of terminal alanine residues
|
|
|
Bacitracin
|
prevents recycling of pyrophosophobactoprenol so NAG-NAM can't attach to peptidoglycan chain
|
|
|
glycopeptides
|
bind to terminal D-alad-ala residues interfere with peptidoglycan chains
|
|
|
beta-lactams
|
interefere with PBPS which prevents crosslinking of peptidoglycan
|
|
|
episome
|
plasmid integrates into bacterial genome
|
|
|
opeon
|
group of functionally related genes
|
|
|
negative control
|
repressor binds to promotor and represses transcription, inducer can bind to repressor to start transcription again
|
|
|
Positive Control
|
both lactose and CAP-cAMP must be present in order for transcription to occur
|
|
|
regulon
|
one regulator protein that controls the expression of several proteins- ex-> CAP
|
|
|
quorum sensing
|
bacteria turn on expression of virulence genes bbased on sensing the conc. of bacteria around
|
|
|
direct DNA repair
|
for pyrimidine dimers and alkylated bases from UV radiation, photoreactivation reverses damage
|
|
|
excision repair
|
removes segment of damaged DNA and synthesizes a new one.
|
|
|
recombination
|
for damage to both strands
|
|
|
SOS response
|
network to detect aned repair damage- can bypass it by mutagenesis
|
|
|
error-prone repair
|
last ditch effort
|
|
|
homologous recombination
|
exchange of DNA when there is a region of homology a nd recombination enzymes/factors like recA
|
|
|
site specific recombination
|
one DNA molecule integrates into another- no homology besides a small portion- ex-> f-plasmid to Hfr. requires restriction endo and exonucleases
|
|
|
Plasmids
|
carry R-factors, toxins, bacteriocins and virulence determinants
|
|
|
r-factors
|
antibiotic resistance genes
|
|
|
bacteriocins-
|
antibacterial agents to similar bacterial strains
|
|
|
bacteriophages
|
viruses that infect bacteria
|
|
|
lytic phages
|
take over host replication- eventually cell lyses
|
|
|
temperage phages
|
integrate into host DNA, go to quiescent stage and eventually environment stimulus pushes them into lytic phase
|
|
|
prophage
|
virus integrated into bacterial DNA
|
|
|
lysogen
|
a bacteria carrying a prophage
|
|
|
Insertion Sequences
|
small, only encode proteins for transposition, flanked by short inverted repeats
|
|
|
Simple Transposon
|
flanked y inverted repeats, carry one or more protein-coding regions unlike ISs, Tn3-> beta lactam resistance
|
|
|
composite transposon
|
flanked by identical IS elements, carry 1+ resistance genes -> Tn5
|
|
|
Pathogenicity Islands
|
carry groups of coordinately regulated virulence genes, mvmt of island within chromosome or to other bacteria
|
|
|
Integrons
|
capture genes, mostly antibiotic resistance genes. NO terminal repeats, contains integrase,
|
|
|
Tramsformation
|
uptake of naked DNA, Gram pos- Bacillus, Strep pneumo, gram neg- neisseria, haemophilus influenza, e.coli. , VERY susceptible to antibiotics
|
|
|
generalized transduction
|
phage DNA injected into host, cells are eventually lysed, phages released
|
|
|
specialized transduction
|
temperate phages are intedgrated into host DNA, small part of baterial gene is transduced into next cell
|
|
|
conjugation
|
form bridge by F plasmid
|
|
|
F+ x F-
|
2 F+
|
|
|
F' X F-
|
2 F'
|
|
|
Hfr X F-
|
Hfr and F-, recipient cell doesn't bcome Hfr
|
|
|
common hospital infections
|
surgical wounds, resp tract infections, UTI (most common),
|
|
|
Most common causes of infection in hospitals
|
staphylocci and e. coli
|
|
|
Sterilization
|
total destruction of all microorganisms
|
|
|
moist heat
|
for sterlization, autoclavin, kills bacteria and spores, used on all heat and moisture resistant items
|
|
|
dry heat
|
for sterilization- kills spores, denatures proteins, causes single strand breaks in DNA, for glass wear and other things that cdan be damaged by steam
|
|
|
Ethylene oxide gas
|
for sterilization- toxic alkylating agent, toxinc byproducts have to dissipate first, for things like bandages
|
|
|
UV radiation
|
for sterilization- for things that can't be heated
|
|
|
disinfection
|
most organisms are destroyed, mycobacteria, viruses, fungi and spores may survive
|
|
|
high level disinfectants
|
for things that cant' be sterilized, endoscopes and plastic instruments, moist heat, glutaraldhyde, hydrogyn peroxide
|
|
|
intermediate level disinfectants
|
alcohol, iodophor, phenolic, for instruments unlikely to be contaminated with spores- don't come in contact with skin like speculum, endoscope
|
|
|
low level disinfection
|
quaternary ammounium compounds, for non-critical instruments like stethoscopes
|
|
|
antisepsis
|
disinfectants to lower numer of microorganisms on skin
|
|
|
alcohols
|
most effective with water, don't kill spores, clean skin before immunization,
|
|
|
phenolic compounds
|
rarely used today- penol coefficient is the rating of activity of a compound compared to phenol
|
|
|
What are 6 examples of acts that would be conversion?
|
[1] Theft,
[2] wrongful transfer, [3] wrongful detention, [4] substantially changing, [5] severely damaging, or [6] misusing a chattel. |
|
|
chlorine
|
hypochoorites are the most widely used chlorine disinfectants
|
|
|
pastuerization
|
heating liquids to destroy harmful organisms- reduced number so they don't cause disease
|
|
|
antibiotics
|
antimicrobial agents made by living organisms
|
|
|
antimicrobials
|
synthetic drugs with antimicrobial properties
|
|
|
Disc-diffusion/ Kirby-Bauer test
|
small disks with antibiotic added to the causitive agent- leaves halos= zone of inhibition
|
|
|
Minimal Inhibitory concentration
|
lowest concentration of the antimicrobial agent which inhibits visible growth
|
|
|
bacteriocidal
|
kills bacteria- used with life-threatning infections and when the immune system is low
|
|
|
bacteriostatic
|
inhibits bacterial growth but doens't kill- used when host defense kills bacteria, so won't work with immunosupprsed patients
|
|
|
Antibiotic Resistance pathways
|
hydrolysis, chemical modification, mutations, altered permeability
|
|
|
Beta lactams
|
inhibit cell wall synthesis- main drug = penicillins, mostly against gram positive like neisseria meningitidis
|
|
|
Cephalosporins
|
cell wall inhibitors, first gen-4th gen by increasining activity against resistant and gram neg bacteria
|
|
|
Tetracyclines
|
inhiit protein synthesis- block A site, used against cholera
|
|
|
aminoglycosides
|
inhibit protein synthesis- block small ribosomal subunit
|
|
|
macrolides
|
inhibit protein synthesis, blocks large ribosomal subunit. erythromycin and azalides are most important drugs. WALKING PNEUMONIA
|
|
|
What is the Intent necessary for
[1] Trespass to Chattels; and [2] Conversion? |
[1] The intent necessary for Trespass to Chattels is intent to do the act that brings about the interference;
[2] The intent necessary for Conversion is the intent to do the act that brings about the interference |
|
|
Koch's Postulates
|
organism required- grown in vitro and inoculated. disease must result. how to identify bacteria that cause disease
|
|
|
Molecular Koch's Postulates
|
Presence of a virulence gene, replacement with wildtype should reverse pathogenicity
|
|
|
molecular guidelines for establishing microbial disease causation
|
pathogen associated sequence, don't need organism
|
|
|
Things that allow bacteria to evade host's immune sys
|
capsule, antigenic mimcry, antigenic masking, production of IgA proteases
|
|
|
Exotoxins Intoxication
|
the toxin in the cause of all of the persons disease, colstridium botulinum, usually consumed, antimicrobials won't work
|
|
|
exotoxin colonization with toxin production
|
bacteria have to be present to produced toxin, cholera and tetans, antibiotics are effective
|
|
|
exotoxin infection and localized tissue damage
|
localized growth of bacteria in a wound, damage to host tissue. clostridium perfringens
|
|
|
A-B Exotoxins
|
diptheria, cholera, tetanus, botulism
|
|
|
membrane disrupting toxins
|
toxins can cause: small pores, large pores, transient pores, membrane perturbing toxins, enzymatic damage to membrane. E. coli, clostridium perfringens
|
|
|
superantigens
|
bridge class II MHC, massive T-cell activation and cytokine release. Staph aureus
|
|
|
helical capsid
|
one subunit, likea spring
|
|
|
icosahedral capsids
|
made of regularly repeating patterns, closed structures
|
|
|
complex capsids
|
modification of icosahedral
|
|
|
syncytia
|
multinucleated cell from multiple fusions with virally infected cells
|
|
|
Types of viral entry
|
direct fusion and recepter mediated uptake
|
|
|
viral DNA replications mechanisms
|
encode their own replication machinery, or push infected cells into the host's cell cycle so it's available
|
|
|
Two ways viruses egress
|
Budding and lysis
|
|
|
tropism
|
range of cell types that support infection and replication of a particular virus- hep b replicates readily in livr cells
|
|
|
host immune response to viruses
|
first- innate response of interferons. NK cells, CTLs antibodys prevent binding of virus to recepter and opsonize them
|
|
|
Plaque Assay
|
detection of cytopathic effect- the more plaque, the more virus
|
|
|
ELISA
|
detection of proteins and antibodys
|
|
|
western blot
|
protein antigen detection
|
|
|
yeast reproduction
|
budding
|
|
|
dimorphic
|
fungi that can grow as both yeast and mold
|
|
|
mold sexual reproduction
|
spores
|
|
|
mold asexual reproduction
|
conidia
|
|
|
Host response to fungi
|
cell mediated immunity- neutrohils, macrophages. no antibodys. in dimorphic fungi- t-cells and IFN gamma
|
|
|
Polyenes
|
class of antifungal drugs, bind to ergostarol, AMMPHOTERICIN B is main drug
|
|
|
Azoles, allyamines, morpholines, thicarbomates
|
inhibit ergostarol synthesis
|
|
|
Potassium Hydroxide preparation
|
best procedure to identify fungi- leaves ehind rigid cell wall, for hair nails skin
|
|
|
Chlorazol black and calcofluor white st ain
|
id fungi by revealing cell wall
|
|
|
india ink stain
|
identify fungi with capsules- cryptococcus neoformans- fungal meningitis
|
|
|
germ tube test
|
id's candida albicans
|
|
|
definitive ost
|
a host where the parasite reaches sexual maturity or adulthood
|
|
|
intermediate host
|
hosst that harbors asexual stages of paraside
|
|
|
classes of protozoa
|
ameba, flagellate, sporozoa, ciliates- first three cause the majority of infections in man- all but sporozoa reproduce by binary fission
|
|
|
sporozan reproduction
|
asexually- schizogony
sexually- sporogeny |
|
|
protozoa
|
single celled eukaryotes, metabolically active stage is called the trophozoite
|
|
|
helminthes
|
multicellular eukaryotes
|
|
|
classes of helminthes
|
nematodes- roundworms
cestodes (tapeworms) and trematodes(flukes)- flat worms *tapeworms are only segmented |
|
|
Mechanical damage of a parasite
|
caused by physical presence or movement w/in host. RBC lysis, obstruction of intestine,
|
|
|
damage caused by parasite products
|
hydrolytic enzymes, - produce persistant infections
|
|
|
immune response to protozoa
|
neutralizing antibody, complement, opsonization, macrophates, CTLs
|
|
|
immune response to helminthes
|
IgE and Eosinophils. Eosinophillia is a hallmark of helminthic infections
|
|
|
Parasitic evasion of immune defense
|
size, anatomical location, cyst, antigenic variation, antigenic masking, immunosupression
|
|
|
treatment of parasites
|
target metabolic differences of differencesi n susceptibility betwen parasite and host
|
