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83 Cards in this Set

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What are the components of LPS? Which type of bacteria have LPS? Match each component to its description below:
1. can act as endotoxin but helps stabilize outer membrane structure too. Induces proinflammatory cytokines like TNF-alpha
2. does not vary much from LPS to LPS
3. protects from host defenses.
1. Lipid A
2. Core
3. O-antigen
Detail each chacaracteristic in Gram positive and Gram negative cells.
1. Peptidoglycan: thick / thin?
2. Teichoic acids: present?
3. LPS: present?
4. Lipid and lipoprotein content: high / low?
5. Flagella structure: 2 rings / 4 gins?
6. Resistance to physical disruption: low / high
Gram positive: thick peptidoglycan, has many teichoic acids, no LPS, low lipid and lipoprotein content, 2 rings in basal body, high resistance to physical disruption

Gram positive: thin peptidoglycan, no teichoic acid, yes LPS, high lipid and lipoprotein content, 4 rings in basal body for flagella structure and low resistance to physical disruption.
Mycolic acids are alpha-substituted beta-hydroxy fatty acids and are found in the genera __________ and __________.

A. Mycobacteria
B. Mycoplasma
C. Nocardia
D. Actinomycetes
E. Treponemes
Mycobacterium, Nocardia

Remember: Mycoplasma do not have peptidoglycan, but mycobacteria are the ones that stain acid-fast.
True or False:
Spirochetes have similar structure as Gram positive bacteria but instead of LPS, they have lipoprotiens.
partial truth, so FALSE!

Replace Gram NEGATIVE with Gram positive and it will be true!
Which bacterium grows in a serpintine cording pattern and has an extractable glycolidpid called "cord factor"?

A. Mycobacteria leprae
B. Mycobacterium tuberculosis
C. Actinomycetes israelii
D. Nocardia asteroides
E. Bordatella pertussis
B. Mycobacterium tuberculosis
Which two genera of bacteria sporulate?

A. Bacillus
B. Listeria
C. Clostridium
D. Escherichia
A. Bacillus, as in Bacillus antracis

C. Clostridium, as in Clostridium perfringes

Bacterial spores are very resistant to heat, toxic chemicals, UV light and dessication. This is due to the synthesis of Calcium dipicolinic acid.
Bacterial spores are very resistant to heat, toxic chemicals, UV light and dessication. This is due to the synthesis of ___________.
Calcium dipicolinic acid.
List the bacterial sporulation steps.
Sometimes if you do a gram stain on an old gram positive specimen, it looks red! Why?
As these cells get older, the hydrolytic enzymes carve up the peptidoglycan. The loss of integrity of the peptidoglycan layer makes it stain gram negative instead of gram positive.
but you will NEVER have a gram negative cell stain gram positive!!
Another reason why a gram positive cell stain gram negative is due to sporulation. Due to the turnover in peptidoglycan.
N-acetyl glucose --> muramic acid (NAM). This is done by linkage of PEP. Antibiotic __________ will inhibit the enzyme that does this. Fosfomycin comes in through the cytoplasmic membrane that normally transports sugars and phosphates. Then it binds to and reacts to the active site of the amino acid of the enzyme that is in charge of that PEP linkage.

A. Bacitracin
B. Cephalosporins
C. Cycloserine
D. Fosfomycin
E. Penicillins
F. Vancomycin
D. Fosfomycin
Description: It is transported in on transporters that transport L-alanine. It is an analog of D-alanine though. It competitively inhibits the enzyme that converts L-Ala --> D-Ala as well as completitively inhibiting the enzyme that converts D-Ala --> D-Ala—D-Ala.

A. Bacitracin
B. Cephalosporins
C. Cycloserine
D. Fosfomycin
E. Penicillins
F. Vancomycin
C. Cycloserine
Next is that the UDP-NAM—pentapeptide is linked to a carrier, bactoprenol, and is phosphorylated. (Has to link up to the carrier to eventually be flipped to the outside of the membrane eventually in the last step.) Then it becomes N-acetyl-muramic acid pantapeptide. (?) That whole thing is transferred across the membrane to the outside via an energy dependent manner. Then it has to be transferred to an existing peptidoglycan strand. The transferase enzyme that catalyzes that is what the antibiotic__________ inhibits. It binds to the D-Alanine—D-Alanine structure and blocks the transferase.

A. Bacitracin
B. Cephalosporins
C. Cycloserine
D. Fosfomycin
E. Penicillins
F. Vancomycin
F. Vancomycin
One of the last/ later steps in peptidoglycan synthesis is the phosphates must be cleaned off. __________ binds with high affinity to the pyrophosphate group and blocks the dephosphorylation. Thus can’t recycle the lipid carrrier.

A. Bacitracin
B. Cephalosporins
C. Cycloserine
D. Fosfomycin
E. Penicillins
F. Vancomycin
A. Bacitracin
Match each antibiotic listed with the reaction that is inhibited: Bacitracin, Cycloserine, Fosfomycin, Vancomycin

1. Transfer of Disaccharide-pentapeptide from the Membrane Lipid Carrier to Cell Wall Acceptor. Binds to D-Ala-D-Ala
2. UDP-N-Acetyl-Glucosamine + PEP > UDP-MuramicAcid
3. Bactoprenol-P-P > Bactoprenol-P + Pi
4. L-Ala > D-Ala
2D-Ala > D-Ala-D-Ala
1. Vancomycin
2. Fosfomycin
3. Bacitracin
4. Cycloserine
Which two are both antibiotics that work INSIDE the cell in the cell cytosol?

A. Bacitracin
B. Cephalosporins
C. Cycloserine
D. Fosfomycin
E. Penicillins
F. Vancomycin
C. Cycloserine
D. Fosfomycin
How is an acid-fast stain/dye done?
Take a sputum sample and, after smearing on a slide, put carbofuscin dye on it then wash with acid alcohol and then methylene blue. If stained with fuscin, then are referred to as acid-fast bacteria.
True or False:
Rifampin binds to the beta subunit of RNA polymerase and blocks the initiation of transcription.
True
Compare and contrast the outer and cytoplasmic membrane for gram negative bacteria.
Outermembrane – has LPS, porins, ion diffusable
Innermembrane- impermeable to ions, has biosynthetic enzymes involved in peptidoglycan synthesis, nutrient transport, electron transport chain.
What are the four distinct phases of bacterial growth?
Lag phase: adaptation to new medium
Exponential (log) phase: balanced increase in all cell constituents with logarithmic increase in cell population.
Stationary phase: results from nutrient limitation, accumulation of toxic products, pH change, reduced oxygen tension
Death phase: time of onset and rate of death
What is the formula for generation time or doubling time?
log (# of bacteria you want at end of time interval) - log (# of bacteria at beginning of time interval) ALLL OVER log2 = # of generations in time t.

Then divide time t OVER that answer and you get the generation time for the bacteria.
All pathogenic bacteria are in the nutritional group of ___________.

A. Photolithotrophic organisms
B. Photoorganotrophic orgs
C. Chemolithiotrophic orgs
D. Chemoorganotrophic orgs
D. Chemoorganotrophic orgs
Describe each and name which can grow in normal air conditions.

1. Obligate aerobes
2. Facultative aerobes / facultative anaerobes
3. Microaerophiles
4. Obligate anaerobes
5. Aerotolerant anaerobes
1. Obligate: require molecular oxygen for metabolism
2. Faciltative: grow in presence of oxygen more efficiently but also has anaerobic means to generate energy (fermentation or anaerobic respiration with an alternate electron acceptor)
3. Microaerophiles: grow best at low oxygen tension, but metabolism requires some oxygen
4. Obligate anaerobes: cannot grow in presence of oxygen, and metabolism does not depend upon molecular oxygen
5. aerotolerant anaerobe: can tolerate oxygen, but do not require it for metabolism, most often use fermentation exclusively

Normal air conditions: obligate aerobes, facultative, aerotolerant anaerobes.
True or False:
All bacteria require CO2 as an essential nutrient in catalytic amounts.
TRUE.

If need more than 0.03% CO2, considered capnophilic.
Most microorgs of medical importance are neutralophiles- grow best at pH of range of ______.
pH 6-8
True or False:
Regardless of external pH, microbes maintain a relatively neutral internal pH by using ATP-driven proton pumps.
TRUE. Ex. Sodium- Hydrogen, or Potassium-Hydrogen exchangers
True or False:
Most microorganisms are mesophiles - grow best in narrow range between 30-40 degrees C.
True
_______ are organic compounds that a cell must contain in order to grow, but which it is unable to synthesize. Examples are: thiamine, biotin, pyridoxine, coblamain, heme.
Growth factors
______ is the process by which molecules move from a region of higher concentraiton to leowr concentration because of random thermal motion. Dependent on size of concentration gradient.

A. Passive diffusion
B. Facilitated diffusion
C. Active diffusion
D. Group translocation
A. Passive diffusion
______ utilizes a protein embedded in the plasma membrane. The rate of this type of diffusion increases with the concentration gradient much more rapidly. Glycerol is an example of something transported this way.

A. Passive diffusion
B. Facilitated diffusion
C. Active diffusion
D. Group translocation
B. Facilitated diffusion
________ is transport of solute molecules to higher concentrations or against a concentration gradient, with the use of metabolic energy.

A. Passive diffusion
B. Facilitated diffusion
C. Active diffusion
D. Group translocation
C. Active diffusion
_______ is the process by which a molecule is transported into the cell while being chemically altered. Ex. mannitol and glucose are usually phosphorylated.

A. Passive diffusion
B. Facilitated diffusion
C. Active diffusion
D. Group translocation
D. Group translocation
What are the 6 F's that allow pathogens to gain entry into the host?
1. Fomites. Objects contaminated with bacteria like rust nails.
2. Flies and other arthropod vectors
3. Feces
4. Fingers
5. Fornication
6. Food
[ Pathogenicity / Virulence ] is the ability of an infecting organism to cause disease. [ Pathogenicity / Virulence ] is the quantification of the ability to cause disease.
Pathogenicity - ability of infecting organism to CAUSE disease.

Virulence - QUANTIFICATION of the ability to cause disease.
[ Auxotrophy / Prototrophy ] is the ability to grow on a defined minimal medium containing just water, inorganic salts and a carbon source. [ Auxotrophy / Prototrophy ] is the inability to grow on a defined minimal medium without some nutritional additive.
Prototrophy ,

Auxotrophy
Regarding point mutations , the most common type of mutation, what is a transition versus a transversion?
Transition = replacement of a purine with a purine or pyrimidine with a pyrimidine.

Transversion = replacement of purine for a pyrimidine or vice versa.

Remeber: purines are adenine and guanine (pure silver) ; and pyrimidines are cytosine, thymine
Substitution of one base with another can cause silent, nonsense or missense mutations. Describe each.
Silent : no change in amino acid sequence encoded.
Missense: substitution of one amino acid for another
Nonsense: creation of a stop codon
Mutations that mask or correct the effects of a prior mutation are called ___________ mutations. There are two types: intragenic and extragenic. Detail both.
suppressor mutations.

Intragenic : the second (suppressive) mutation occurs in the SAME gene as the first mutation.
Extragenic : the second suppressive mutation occurs in a DIFFERENT gene than the first mutation.
True or False:
Transposons are genetic elements taht have the ability to move-transpose- between sites on DNA by non-homologous recombination (as opposed to homologous recombo which occurs between two similar DNA sequences).
True
Homologous recombo (by single crossover) between two copies in the [ opposite / same ] orientation results in a deletion mutation.
same orientation


oppositve orientation --> inversion mutation
This test asked whether exposure to a selective agent induces mutations at the time of exposure or merely selects for cells possessing pre-existing mutations.

A. The Fluctiation Test: Luria and Delbruck (1943)
B. Ames Test
A. The Fluctiation Test: Luria and Delbruck (1943)

Exposure to bacteriophage selected for pre-existing cells that mutated to bacteriophage resistance while growing in the incubating tube. The number of colonies on each play varied dramatically depending on when the bacteirophage-resistant cells arose during culture in the tube. Thus, the experiment suggested that mutations occur randomly and are not induced by the selective agent (bacteriophage).
Which of the following is NOT true about bacterial conjugation?
A. Requires cell-to-cell contact
B. Transfers genetic material bi-directionally
C. Is not sensitive to DNase
B. Transfers genetic material bi-directionally IS FALSE because conjugation is only uni-directional.
Which of the following is blocked by addition of DNase?

A. Conjugation
B. Transformation
C. Transduction
D. Translation
B. Transformation
Which does require cell-to-cell contact?

A.Transformation
B. Transduction
C. Translation
D. Lysogenic variation
E. None
E. None (all of these do not require it - ONLY bacterial conjugation requires cell cell contact)
True or False:
During bacterial conjugation, a complementary strand is made in both cells.
True!

*F-encoded endonuclease makes a single-strand cut at oriT site on F
*DNA strand passes into recipient cell
*Complementary strand is made in both cells
*Cytoplasmic bridge breaks down. The two cells separate
Both are now F+ donors
What is Hfr formation? F can integrate into...
F can integrate into chromosome. This occurs by a single cross-over between homologous sequences on F and the chromosome
Mix Hfr and F–; get recombinant [ F+ / F– ] recipients.
Mix Hfr and F–; get recombinant F– recipients

Donor tra operon enters last, if at all. Very few recipients become donors because this requires transfer of the entire chromosome; transfer is spontaneously interrupted
Hfr transfer differs from transfer of the F factor in that:

A. Hfr transfer requires the tra operon but F transfer does not.
B. Hfr transfer requires that the F plasmid be integrated into the chromosome of the donor cell, but F transfer does not.
C. F factor transfer requires a recipient cell that is F- but Hfr transfer does not.
D. F factor transfer requires cell-to-cell contact but Hfr transfer does not.
B. Hfr transfer requires that the F plasmid be integrated into the chromosome of the donor cell, but F transfer does not.
How is F' formed?
Integrated F can excise (Clean excision). Returns to life as F
Might pick up adjacent chromosomal genes.

Called F' (“F prime”)
Transferred like F
Mix F’ and F–; Get___ recipients
Mix F’ and F–; Get F’ recipients
E. coli strain A is pro+ and contains an F plasmid in some form. Strain A is mated to strain B, which is pro- and F-. The progeny of this mating are pro+, but are incapable of further rounds of mating. Strain A is MOST LIKELY:

A. F-
B. F+
C. F'
D. Hfr
D. Hfr

Pro+ means it has some kind of F (eliminate F-). F by itself wouldn’t transfer pro+ .
Incapable of further rounds of mating means that the answer is D. F’ is the same pretty much as F+ and can donate. Hfr cannot donate.
True or False:
Griffith experiment was the first demonstration of bacterial transduction.
FALSE.

Should be transformation. (rough + heat killed smooth --> killed mouse and from the mouse they acquired smooth org.) Transduction is viruses.
When bacterial strain A (ermr lac–) is mixed with strain B (erms lac+), growth is observed on plates containing lactose as the sole carbon source and erythromycin. (No growth is observed on these plates with either strain alone.) Growth is also observed if the filtered supernatant from strain A is added to strain B, but not if the supernatant is first treated with DNase. Growth is not observed if the supernatant from strain B is added to strain A. The most likely explanation for the results of the first experiment is:

A. Erythromycin resistance was transferred from strain A to strain B by conjugation.
B. Erythromycin resistance was transferred from strain A to strain B by transformation.
C. Erythromycin resistance was transferred from strain A to strain B by transduction.
D. Lactose utilization was transferred from strain B to strain A by transformation.
E. Lactose utilization was transferred from strain B to strain A by transduction.
B. Erythromycin resistance was transferred from strain A to strain B by transformation.

For this problem, you NEED to remember that:
1) conjugation NEEDS cell to cell contact so if you filter supernatant, it doesn't work
2) Transformation can still work with filtered supernatant but doesn't work with DNase
3) For Transduction, neither addition of DNase nor filtration will block gene transmission
For _______, neither addition of DNase nor filtration will block gene transmission

A. Conjugation
B. Transformation
C. Transduction
D. Translation
C. Transduction
True or False:
During bacterial conjugation, a complementary strand is made in both cells.
True!

*F-encoded endonuclease makes a single-strand cut at oriT site on F
*DNA strand passes into recipient cell
*Complementary strand is made in both cells
*Cytoplasmic bridge breaks down. The two cells separate
Both are now F+ donors
What is Hfr formation? F can integrate into...
F can integrate into chromosome. This occurs by a single cross-over between homologous sequences on F and the chromosome
Mix Hfr and F–; get recombinant [ F+ / F– ] recipients.
Mix Hfr and F–; get recombinant F– recipients

Donor tra operon enters last, if at all. Very few recipients become donors because this requires transfer of the entire chromosome; transfer is spontaneously interrupted
Hfr transfer differs from transfer of the F factor in that:

A. Hfr transfer requires the tra operon but F transfer does not.
B. Hfr transfer requires that the F plasmid be integrated into the chromosome of the donor cell, but F transfer does not.
C. F factor transfer requires a recipient cell that is F- but Hfr transfer does not.
D. F factor transfer requires cell-to-cell contact but Hfr transfer does not.
B. Hfr transfer requires that the F plasmid be integrated into the chromosome of the donor cell, but F transfer does not.
How is F' formed?
Integrated F can excise (Clean excision). Returns to life as F
Might pick up adjacent chromosomal genes.

Called F' (“F prime”)
Transferred like F
Mix F’ and F–; Get___ recipients
Mix F’ and F–; Get F’ recipients
E. coli strain A is pro+ and contains an F plasmid in some form. Strain A is mated to strain B, which is pro- and F-. The progeny of this mating are pro+, but are incapable of further rounds of mating. Strain A is MOST LIKELY:

A. F-
B. F+
C. F'
D. Hfr
D. Hfr

Pro+ means it has some kind of F (eliminate F-). F by itself wouldn’t transfer pro+ .
Incapable of further rounds of mating means that the answer is D. F’ is the same pretty much as F+ and can donate. Hfr cannot donate.
True or False:
Griffith experiment was the first demonstration of bacterial transduction.
FALSE.

Should be transformation. (rough + heat killed smooth --> killed mouse and from the mouse they acquired smooth org.) Transduction is viruses.
When bacterial strain A (ermr lac–) is mixed with strain B (erms lac+), growth is observed on plates containing lactose as the sole carbon source and erythromycin. (No growth is observed on these plates with either strain alone.) Growth is also observed if the filtered supernatant from strain A is added to strain B, but not if the supernatant is first treated with DNase. Growth is not observed if the supernatant from strain B is added to strain A. The most likely explanation for the results of the first experiment is:

A. Erythromycin resistance was transferred from strain A to strain B by conjugation.
B. Erythromycin resistance was transferred from strain A to strain B by transformation.
C. Erythromycin resistance was transferred from strain A to strain B by transduction.
D. Lactose utilization was transferred from strain B to strain A by transformation.
E. Lactose utilization was transferred from strain B to strain A by transduction.
B. Erythromycin resistance was transferred from strain A to strain B by transformation.

For this problem, you NEED to remember that:
1) conjugation NEEDS cell to cell contact so if you filter supernatant, it doesn't work
2) Transformation can still work with filtered supernatant but doesn't work with DNase
3) For Transduction, neither addition of DNase nor filtration will block gene transmission
For _______, neither addition of DNase nor filtration will block gene transmission

A. Conjugation
B. Transformation
C. Transduction
D. Translation
C. Transduction
For _______, filtration won't hinder it but addition of DNase will block gene transmission

A. Conjugation
B. Transformation
C. Transduction
D. Translation
B. Transformation
For _______, filtration will hinder gene transmission.

A. Conjugation
B. Transformation
C. Transduction
D. Translation
A. Conjugation
[ Endotoxins / Exotoxins ] are highly variable in structure and function, induce direct damage through a variety of mechanisms and are produced by both Gram + and Gram - bacteria.
Exotoxins
[ Endotoxins / Exotoxins ] are NOT highly variable in structure and function, cause collateral damage through inflammation and are produced by Gram - bacteria only
Endotoxins.
Endotoxins are produced by [ Gram + / Gram - / both ] and extotoxins are produced by [ Gram + / Gram - / both ] .
Endo = Gram -

Exo:= both Gram + and Gram -
Types of exotoxins include: cytotoxins (pore-forming and cytoskeleton disrupting), enterotoxins, ADP-ribosylating toxins. Name the three examples of ADP-ribosylating toxins.
1) Cholera Toxin (Vibrio cholerea): ADP-ribosylation of Gs protein --> increase cAMP --> alters ion balance and net flow of Cl from tissue to intestinal lumen --> diarrhea "rice-stool"
2) Pertussis Toxin (Bordatella pertussis): Induces constitutive adenlate cycalse activity --> increase cAMP levels --> prevents phagocyte-mediated killing.
3) Diptheria Toxin (Corynebacterium diptheria): ADP-ribosylation of elongation factor (EF2) thus inhibits protein synthesis.
Which ADP-ribosylating toxin does this describe: ADP-ribosylation of Gs protein --> increase cAMP --> alters ion balance and net flow of Cl from tissue to intestinal lumen

A. Cholera Toxin (Vibrio cholerea)
B. Pertussis Toxin (Bordatella pertussis)
C. Diptheria Toxin (Corynebacterium diptheria)
D. Botulinum Toxin (Clostridium botulinum)
E. Tetanus Toxin (Clostridium tetani)
Cholera Toxin (Vibrio cholerea)
Which ADP-ribosylating toxin does this describe:
Induces constitutive adenlate cycalse activity --> increase cAMP levels --> prevents phagocyte-mediated killing
A. Cholera Toxin (Vibrio cholerea)
B. Pertussis Toxin (Bordatella pertussis)
C. Diptheria Toxin (Corynebacterium diptheria)
D. Botulinum Toxin (Clostridium botulinum)
E. Tetanus Toxin (Clostridium tetani)
B. Pertussis Toxin (Bordatella pertussis)
Which ADP-ribosylating toxin does this describe:
ADP-ribosylation of elongation factor (EF2) thus inhibits protein synthesis.
A. Cholera Toxin (Vibrio cholerea)
B. Pertussis Toxin (Bordatella pertussis)
C. Diptheria Toxin (Corynebacterium diptheria)
D. Botulinum Toxin (Clostridium botulinum)
E. Tetanus Toxin (Clostridium tetani)
C. Diptheria Toxin (Corynebacterium diptheria)
Which of the following toxins is a neurotoxin that actually has three types?
A. Cholera Toxin (Vibrio cholerea)
B. Pertussis Toxin (Bordatella pertussis)
C. Diptheria Toxin (Corynebacterium diptheria)
D. Botulinum Toxin (Clostridium botulinum)
E. Tetanus Toxin (Clostridium tetani)
D. Botulinum Toxin (Clostridium botulinum)

1) foodborne botulism - associated with consumption of preformed toxin present in home canned foods. Is an intoxication- not an infection
2) infant botulism - associated with consumption of C. botulinum spores in foods like honey. Bacteria germinate and produce toxin. Normal GI flora and immune system of adults do not allow growth of oragnism.
3) wound botulism - very rare, toxin production occurs in teh wound, symptoms are similar to foodborne botulism
__________ are produced by viruses, bacteria and mycoplasma. They may be secreted or remain part of the cell membrane. Soluble superantigens produced by Staph aureus and Strpe pyogenes are responsible for TSS. These are potent stimulators of T cells!
superantigens

Instead of antigenic peptide fragments binding WITHIN the antigen binding groove of class II MHC molecules, they instead bind DIRECTLY onto the lateral side of MHC class II molecules APC cells. This complex only recognizes the Vb element of the T cell receptor and thus any T cell with the right Vb element can be stimulated, whereas normally antigen specificity is also required! Superantigens can bind many APC cells. This results in massive production and release of cytokines (including IL1 and TNF alpha and subsequent shock).
True or False:
Lipid A is the outermost portion of the LPS.
FALSE. Lipid A is the innermost (membrane embedded portion) of LPS but it IS the toxic component. (Since it is not exposed, the effects of the molecule is only felt when the cell is lysed and LPS is released).
Physiological response to LPS includes:
1) fever - stimulates the release of cytokines. Name the three that play key roles in eliciting the fever response.
2) neutropenia
3) disseminated intravascular coagulation
4) hypotension- due to vascular leakage
5) vascular collapse and multi organ system failure
1) TNG, IL-1, IL-6
Differentiate between toxin, toxicity, toxinosis.
Toxin: A poisonous substance
Toxicity: The degree to which a toxin is poisonous
Toxinosis: A toxin-mediated disease
What are the things that grow on MacConkey's agar? (3 groups)
Gram negative bacteria, and can differeniate between Lac- and Lac +

Yersinia pestis (Bubonic plague) --> white colonies

Enterobacteriae:
Lac + like E.coli --> red colonies
Lac - like Salmonella, Shigella --> white colonies
What organism can be plated on NYC agar or MTM agar? (1)
N. meningitidis
Key test for distinguishing streptococci from staphylococci is:

A. Catalse test
B. Oxidase test
C. Agglutination test
D. Indole test
A. Catalse test

Both are Gram +, but only staphylococcus is Catalase + too!
The key test for distinuishing staphylococcus aureus from all other staph is...

A. Catalse test
B. Oxidase test
C. Coagulase test
D. Indole test
C. Coagulase test
Which are distinguished by amplification tests (sensitive) and/or serological tests (complement fixation, ELISA, cold agglutinin reactions), but note culture of sputum on medium since that is too slow and insensitive?

A. Mycobacteria
B. Mycoplasma
C. Treponemes
D. Actinomycetes
B. Mycoplasma

* lack peptidoglycan
* colonies look like "fried eggs"
*pleomorphic and V.SMALL!
*very slow growth (1-2 weeks to double!) and very fastidious

Treat with tetracylcine and erythromycin. (M.pneumoniae, M. genitalium, M. hominis, Ureaplasma urealyticum)
True our False:
Indole tests rapidly for identifying E. coli and fastidious gram-negative rods.
True