Cmmb 343

Front 1

Who was Robert Hooke

Back 1

Was the first to describe microorganisms by describing the fruiting structures of molds

Front 2

Antoni van Leeuwenhoek.

Back 2

Used extremely simple microscopes of his own construction to view natural substances for their microbial content.

Front 3

Pasteur

Back 3

Developed and proved methods of sterilzation (pasture flask).

Front 4

Robert Koch

Back 4

created the 'germ theory of disease' and developing "Koch's postulates"

Front 5

Koch's Postulates

Back 5

For proving that an organism causes a disease.
1. only present in sick animals
2. cultivated in a pure culture
3. animal inoculated with pure culture must become sick
4. recultivated in lab and must be same as original.

Front 6

Who first used agar as a solidifying agent?

Back 6

Walter Hesse.

Front 7

What are the three classes of organisms based on their ability to attain energy.

Back 7

1.Chemoorganotrophs (use organic compounds)
2. Chemolithotrophs (use inorganic compounds H2S and NH3)
3. Phototrophs (use light)

Front 8

How are organisms classified via their carbon source utilization

Back 8

1. Heterotrophs (one or more organic compounds as carbon source)
2. Autotrophs (CO2 is main source, called primary producers synthesizing organic material from CO2)

Front 9

Reconstruction of the universial evolutionary tree of life was base on

Back 9

comparative 16S rRNA sequence analysis. because..
1. universial to all species and functionally homologous.
2. Not transferred from one species to another
3. Large enough to contain suficient information for comparison
4. Evolves slowly.

Front 10

Phylogenetic trees are constructed by..

Back 10

The more sequences that two species have in common the closer they are. # differences / total # AA's

Front 11

The three major phylogenetic groups

Back 11

Bacteria, Archaea, Eukarya

Front 12

characteristics used to determine a bacterial species

Back 12

- 16S rRNA
- DNA-DNA hybridization
- Physiological and morphological characters.

Front 13

Proteobacteria

Back 13

- Largest group
- many chemoorganotrophic (E. coli), also photo and chemolitho.
-Live in soil, water, conjunction with plants or animals.

Front 14

Gram-positive bacteria
(as a phylogeny)

Back 14

- Common cell wall structure
- Spore formers (bacilus), antibiotic producing (streptomyces), lactic acid producers (lactobacillus)

Front 15

Cyanobacteria

Back 15

seperate lineage

Front 16

Green sulfur and Green non sulfur bacteria

Back 16

Two seperate lineages with bacteria contianing photosynthetic pigments. Most grow as autotrophs.
- Green non sulfur bacteria inhabits hot springs and shallow marine bays.
- microbial mats

Front 17

Deinococcus lineage

Back 17

unusual cell walls, highly resistant to radiation

Front 18

Chlamydia lineage

Back 18

-Obligate intracellular pathogen avoid immune response.
- Contains organisms that cause respiratory diseases in humans.

Front 19

Aquifex and Thermotoga

Back 19

Ancient Branches
- Both grow at high temperatures near boiling point.

Front 20

_______% of bacterial Phyla and _____% of bacterial species in nature have never been grown in lab.

Back 20

75%
95%
The great plate mystery

Front 21

How do Archaea differ from Bacteria and Eukarya

Back 21

- Cell wall structure and chemistry
- membrane lipid structure
- molecular biology
- metabolism
* Many are extremophiles

Front 22

Methanogens

Back 22

Archaea
- Strick anaerobes (can not tolerate oxygen)
- metabolism produces methane
- important for biodegreadation of organic material.

Front 23

Halophilic archaea

Back 23

- Can grow in and on salt crystals.
- Inhait salt lakes salterns a
relatives ot the methanogens.

Front 24

ENV-0P2

Back 24

candidate phylum. Unknown organisms and diversity that no one has been able to grow in their lab.

Front 25

What is an extremophile?

Back 25

Organisms that prefer conditions outside the limits of what is "normal"

Front 26

Examples of thermophilic habitats

Back 26

- Deserts
- Compost, decaying organic matter
- Deep biosphere
- Geothermal systems(hot springs)

Front 27

What is the effect of temperature on reaction rate?

Back 27

Increase in temp = increase in rxn rate of an enzyme TO A POINT.
- High temps increase
1. Number of collisions
2. Energy of collision (activation energy)

Front 28

At too high of temperatuers what are three main negative effects...

Back 28

1. protein denaturation
2. Membrane becomes too fluid (things diffuse too quickly)
3. DNA/RNA instable

Front 29

Arrhenius' equation is useful for..

Back 29

Measuring the rate of reaction.
y = b - mx
log K = log A - Ea/RT

Front 30

Critical Points of a psycrophile, mesophile, thermophile and hyperthermophile

Back 30

Psycrophile -40 to 15
Mesophile 15 - 60
Thermophile 60 - 80
Hyperthermophile +80

Front 31

Upper limits for metabolism in geothermal systems..

Back 31

Phototroph to 74 C
Organotroph to 90 C
Lithotroph to 113 C or higher
H2 H2S and S are ususally primary energy sources

Front 32

Psychrophiles are also often ________ because..

Back 32

Halophiles, they live in small pockets of water that exist in ice. These pockets are high in [salt]

Front 33

Ranges and Names for pH

Back 33

Acidophiles pH 0-5.5
Neutrophiles pH 5.5-8.5
Alkalophiles 8.5-11.5
Acidophile champion (Ferroplasma acidarmanus)
Alkaliphile (Natronobacterium gergoryi)

Front 34

The cytoplasm must remain ____

Back 34

Neutral, min of 4.6 and a max of 9. Cell membrane must be very impermeable to protons.
Causes problems for maintining a proper proton motive force and enzyme denaturation.

Front 35

Deinococcus

Back 35

Is a microorganism that is radiation tolerant of up to 1500000 rad. DNA repair mechanisms and 4 copies of DNA present in cell.

Front 36

Oxygen concentrations...

Back 36

- Areobic : need oxygen to grow
- Anerobic : do not like oxygen for growth. Grow at bottom
- Faculatiative: can change enzymes to function if O2 present. Growth throughout, concentrated on surface.
- Aerotolerant: Not dependent on oxygen, growth throughout.

Front 37

At what percent w/w does salt crystalize out of water.

Back 37

above 36%
Sea water is 3.5%
Hypersaline solution 35.8%

Front 38

4 Categories of halophiles

Back 38

- Slight or mild (1-6%)
- Moderate (7-15%)
- Extreme halophile (>15%)
- Halotolerant: Optimum below 1% but can tolderate sea water or higher.

Front 39

Osmotic stress strategies..

Back 39

1. Salt in: accumulate KCL, need salt adapted enzymes, brings water into cell.
2. Compatible solutes: create organic molecules, requires energy, that serve a cytoplasmic solutes to balance water relations.

Front 40

Water activity range

Back 40

aw

aw=1 = free water
aw = 0 = no water
sea water aw = 0.75

Front 41

The cell envelope contains

Back 41

Membrane(s) and cell wall

Front 42

Gas vesicles are used for

Back 42

Buoyancy regulators, permeable to gas but not water. Common in hyer saline and or aquatic organisms.

Front 43

Internal membranes are found in what types of bacteria.

Back 43

Photosynthetic, Nitrifying and Methanotrophic.
Membranes include embeded enzymes that are essential for growth.

Front 44

Gram positive cell envelopes

Back 44

Cytoplasmic membrane
peptidoglycan, and teichoic acids.
Purple stain
Thick peptidoglycan layer holds crystal violet in.
- can withstand more pressure

Front 45

Gram negative cell envelopes

Back 45

Cytoplasmic membrane
peptidoglycan
periplasm
and outter membrane
- Red stain

Front 46

Gram positive cell membranes contain

Back 46

Complex lipids: phosphatidy ethanolamine (ester bond in the head region)
- Hopanoids are in membrane to add stability.

Front 47

Lipid membranes are semi permiable to..

Back 47

water, alcohol, nonpolar solvents, O2 and NH3.

Front 48

Lipid membranes are impermeable to..

Back 48

Ions, sugars and amino acids.

Front 49

Lipid membranes have the fluidity of a..

Back 49

light grade oil.

Front 50

How do membranes adapt to temperatures

Back 50

Saturation.
As temp increases membrane becomes more fluid, to counteract this fatty acids are saturated (strait chains) with no kinks to allow for dense packing.

Front 51

Membranes are used for..

Back 51

Permeability barrier
Protein anchor
Energy conservation (H motive force)

Front 52

Functions of membrane proteins include..

Back 52

- Lipid synthesis, cell wall synthesis, nutrient transport, signal transduction, protein secretion, chemotaxis, electron transport.

Front 53

What enzyme breaks down peptidoglycan

Back 53

lysozyme (tears and egg whites)
And
Penicillin (inhibits cross linkage of the glycan strands of peptidoglycan)

Front 54

FtsZ cell division

Back 54

- FtsZ proteins form a ring at center of cell
- Part of complex called divisome
Peptidoglycan synthesizing enzymes located here
- Recruits other cell divison proteins.

Front 55

Steps in peptidoglycan synthesis

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1. Assembly of disaccharide-peptide monomer and translocation
2. Transglycosylation (moved outside of cell)
3. Transpeptidation (cross linked)

Front 56

Teichoic acids

Back 56

- Negatively charged
- Found in gram positive cells
- It is a phosphate ester
- Covalently linked to peptidoglycan and sometimes lipids
- Strongly antigenic (acted on by antibodies)

Front 57

Functions of teichoic acids

Back 57

- Maintain porosity of cell wall
- Maintian shape
- Capture essential cations, and toxic cations
- Reservior of phosphate.

Front 58

Functions of bacterial cell wall

Back 58

- Prevent lysis
- Define shape
- Cation binding
- Molecular sieve (antibiotics and toxic enzymes)

Front 59

The periplasmic proteins..

Back 59

- binding proteins (ABC transporters)
- hydrolytic enzymes, proteases, nucleases and phosphatases
- protective enzymes
- chemoreceptors
- biosynthesis
- some members of electron transport chain.

Front 60

How does two component signal transduction work

Back 60

Environmental signal interacts with the sensor kinase.
- ATP --> ADP
- Response regulator is Phosphorylated
- Regulator acts to repress or activate DNA synthesis.

Front 61

Porins are..

Back 61

- Found in outter membrane of Gram Negative cells
- Channels of the entrance and exit of hydrophilic low molecular weight molecules.

Front 62

Lipopolysaccharide (LPS)

Back 62

- Hydrophilic
- Protects from detergents
- It is a endotoxin
- Outside of outter membrane
- repeating sugar units on fatty acid base.

Front 63

What is endotoxic shock

Back 63

- Occurs when LPS enters the blood stream
- Fever, diarrhea and fatal shock.
- Can still cause shock even after bacteria are dead.

Front 64

What is the capsule

Back 64

huge layer of "goo" around the outside of the cell.
- Capsular polysaccharide, exopolysaccharide (glycocalyx)
- For adhesion, protection, virulence factor, and movement (ingliding bacteria)

Front 65

S Layer

Back 65

Honeycomb type structure, replaces capsule.

Front 66

Three types of flagella

Back 66

- Peritrichous (all over)
- Polar (single)
- Lepotrichous (several polar)

Front 67

What are pili and fimbriae

Back 67

Fimbriae used for attachment
Pili made from protein, function in adhesion or attachment, sex or conjugation (gene transfer).

Front 68

Archaea cell envelopes all have

Back 68

S layer and pseudo peptidoglycan.

Front 69

Difference between bacteria and archea in complex lipids.

Back 69

Bacteria have ester linkages and Archaea have Ether linkages.

Front 70

Types of lipids in archaea

Back 70

- Glycerol diether
- Diglycerol tetraether (decrease fluidity)
- Lipid bilayer
- Lipid monolayer

Front 71

Archaeal membranes : LIpids

Back 71

- Ether linkages are an advantage in acidic and thermophilic environments. More resistant to hydrolytic leavage than ester bonds.

Front 72

Pseudomurein or Pseudopeptidoglycan

Back 72

- Found in methanoaterium
- Closest equivalent to peptidoglycan
- no N-acetylmuramic acid and no D-amino acids
- consists of repeating sugars of N-acetylglucosamine and N-acetyltalosaminuronic acid
Linkage is beta 1-3 (not recognized by lysozyme)