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Flashcards in Unit 1 Deck (48)
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1
Q

layers of peptidoglycan connected by

A

NAM-NAM linkages between 3rd AA and 4th AA (D-ala)

2
Q

peptidoglycan single layer consists of

A

alternating nam and nag units

3
Q

PBP

A

penicillan binding proteins - transpeptidases and carboxypeptidases

4
Q

transpeptidases

A

catalyze formation of NAM-NAM cross link

5
Q

carboxypeptidases

A

clease the fifth D-ala and produce ATP during formation of the NAM-NAM cross link

6
Q

S layer

A

highly organized layer of protein and glycoprotein present in archael species - binding and attacking host cells, biofilm formation

7
Q

slime layer

A

easily removable layer for protection and adherance

8
Q

magnetosomes

A

organelle containing mineral magnetite - for sensation of magnetic field

9
Q

PHB and PHA

A

polymers from storage granules for phototrophs to use in low light conditions

10
Q

carboxysomes

A

protein-enclosed compartment containing rubisco to fix carbon dioxide

11
Q

stalk

A

extension of cytoplasm and envelope to attach to a substrate

12
Q

nanotubules

A

extension of cell envelopes that connect cytoplasm or periplasm of different cells

13
Q

B lactam drugs

A

bind to PBPs and inhibit them to prevent synthesis of new cell wall

14
Q

how do bacteria fight against B lactam drugs

A

B lacatmases

15
Q

vancomycin

A

not a B lactam drug but works in same space - prevents fifth D-ala from leaving so cross link cannot form

16
Q

gram positive phylum

A

firmicutes

17
Q

gram negative phylum

A

proteobacteria

18
Q

firmicute peptidoglycan contains

A

techoic acid to give it negative charge

19
Q

organization of proteobacteria cell wall

A

outer membrane (LPS then lipoprotein) thin peptidoglycan layer, inner membrane (plasma)

20
Q

LPS

A

lipopolysaccharide - endotoxin released upon cell death O antigen, core, lipid A tail

21
Q

archael cell wall structure

A

NAG-NAT pseudopeptidoglycan, S layer

22
Q

why are archaea resistant to b lactam drugs and lysozyme

A

no nam-nam linkages (b lactam) no nam-nag linkages (lysozyme)

23
Q

stages of gram staining

A

crystal violet - purple gets between peptidoglycan layers; iodine (mordant) - forms complex; alcohol - washes away complex and dissolves outer membrane; safranin - dies gram negative pink

24
Q

acid fast staining

A

used for mycobacterium - steam melts waxy mycolic acid - then dye - cools, wax solidifies and traps dye - won’t wash away, indicates mycobacterium

25
Q

spore stain

A

malachite green to detect spores (bacillus and clostridium)

26
Q

negative stain

A

has negative charge to repel negative charge of cell wall - visualizes capsule

27
Q

phototroph

A

uses light as source of energy

28
Q

chemotroph

A

uses organic or inorganic compound as source of energy (not carbondioxide)

29
Q

lithotrophs

A

electron source is inorganic molecule (hydrogen gas, sulfur)

30
Q

organotroph

A

electron source is organic molecule

31
Q

heterotroph

A

carbon source is preformed organic molecule

32
Q

autotroph

A

use carbon dioxide as primary carbon source

33
Q

ABC transporter

A

solute binding proteins bind to solute that needs entering - complex binds to ABC transporter, ATP used to open transport protein

34
Q

siderophores

A

binds free iron to transport into bacterial cells

35
Q

group translocation

A

chemically alters substrate during transport to hack gradient

36
Q

PTS

A

phototransferase system, uses energy from PEP byproduct to attach phosphate to sugars during group translocation

37
Q

SOD

A

superoxide dismutase to neutralize superoxide anion (present in obligate aerobes, facultative anaerobes, aerotolerant and microaerophiles)

38
Q

catalase

A

breakdown of hydrogen peroxide (present in obligate aerobes, facultative anaerobes, maybe in microaerophiles)

39
Q

blood agar

A

red, enriched; differential for hemolysis

40
Q

differentiation on blood agar

A

no color change - gamma, normal growth;
green - alpha, partial hemolysis;
white - beta, complete hemolysis

41
Q

EMB agar

A

selective for gram negative, differential for ability to ferment lactose

42
Q

differentiaion on EMB agar

A

determine by acidification;
clear - no fermentation;
pink - some fermentation
green - lots of fermentation (e coli)

43
Q

mannitol salt agar

A

pink agar selective for halophiles, gram positive; differential for fermentation of mannitol (generally used for staph)

44
Q

differentiation on mannitol salt agar

A

pink - no fermentation;

yellow - fermentation

45
Q

citrate agar

A

green agar selective for gram negative, differential for citrate as carbon source

46
Q

differentiation on citrate agar

A

green - can’t use citrate;

blue - can use citrate

47
Q

SIM agar

A

sulfure reduction, indole production, motility

48
Q

appearance on SIM agar

A

black precipitation for sulfur reduction;
red ring for indole;
turbid throughout for motility