Unit 1 Flashcards Preview

Microbiology > Unit 1 > Flashcards

Flashcards in Unit 1 Deck (48):
1

layers of peptidoglycan connected by

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

2

peptidoglycan single layer consists of

alternating nam and nag units

3

PBP

penicillan binding proteins - transpeptidases and carboxypeptidases

4

transpeptidases

catalyze formation of NAM-NAM cross link

5

carboxypeptidases

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

6

S layer

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

7

slime layer

easily removable layer for protection and adherance

8

magnetosomes

organelle containing mineral magnetite - for sensation of magnetic field

9

PHB and PHA

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

10

carboxysomes

protein-enclosed compartment containing rubisco to fix carbon dioxide

11

stalk

extension of cytoplasm and envelope to attach to a substrate

12

nanotubules

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

13

B lactam drugs

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

14

how do bacteria fight against B lactam drugs

B lacatmases

15

vancomycin

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

16

gram positive phylum

firmicutes

17

gram negative phylum

proteobacteria

18

firmicute peptidoglycan contains

techoic acid to give it negative charge

19

organization of proteobacteria cell wall

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

20

LPS

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

21

archael cell wall structure

NAG-NAT pseudopeptidoglycan, S layer

22

why are archaea resistant to b lactam drugs and lysozyme

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

23

stages of gram staining

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

acid fast staining

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

25

spore stain

malachite green to detect spores (bacillus and clostridium)

26

negative stain

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

27

phototroph

uses light as source of energy

28

chemotroph

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

29

lithotrophs

electron source is inorganic molecule (hydrogen gas, sulfur)

30

organotroph

electron source is organic molecule

31

heterotroph

carbon source is preformed organic molecule

32

autotroph

use carbon dioxide as primary carbon source

33

ABC transporter

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

34

siderophores

binds free iron to transport into bacterial cells

35

group translocation

chemically alters substrate during transport to hack gradient

36

PTS

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

37

SOD

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

38

catalase

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

39

blood agar

red, enriched; differential for hemolysis

40

differentiation on blood agar

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

41

EMB agar

selective for gram negative, differential for ability to ferment lactose

42

differentiaion on EMB agar

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

43

mannitol salt agar

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

44

differentiation on mannitol salt agar

pink - no fermentation;
yellow - fermentation

45

citrate agar

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

46

differentiation on citrate agar

green - can't use citrate;
blue - can use citrate

47

SIM agar

sulfure reduction, indole production, motility

48

appearance on SIM agar

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