Regulation of Bacterial Gene expression

Question 1

in bacteria, multiple genes can be in the same transcription unit

Answer 1

operon

Question 2

a sequence of DNA bases that is transcribed to give a single, discrete complementary RNA

Answer 2

transcription unit

Question 3

Toxin B and holin

Answer 3

operon

Question 4

positive regulator

Answer 4

tcdR

Question 5

toxin B

Answer 5

tcdB

Question 6

holin

Answer 6

tcdE

Question 7

ToxinA

Answer 7

tcdA

Question 8

negative regulator

Answer 8

tcd C

Question 9

positive regulator, toxin B, holin, Toxin A, negative regulator

Answer 9

pathogenicity locus

Question 10

special region of DNA where RNA polymerase binds for the purpose of initiating transcription

Answer 10

Promoter site

Question 11

a site within the DNA or RNA product at which RNA synthesis stops

Answer 11

Termination Site

Question 12

two key elements of most promoters

Answer 12

-35 and -10

Question 13

blocks elongation

Answer 13

rifamycins

Question 14

blocks initiation

Answer 14

lipiarmycins

Question 15

example of a lipiarmycins

Answer 15

fidaxomicin

Question 16

exampled of rifamycins

Answer 16

rifampicin

Question 17

inhibitors of RNA synthesis that bind to Beta subunit of RNA polymerase

Answer 17

Rifamycins and Lipiarmycins

Question 18

necessary for recognition of the promoter region of a gene

Answer 18

sigma subunit

Question 19

Release of ______ after initiation of transcription from ______

Answer 19

sigma subunit from the holoenzyme

Question 20

alpha-2-Beta-Betaprime-sigma

Answer 20

Holoenzyme

Question 21

alpha-2-Beta-Betaprime

Answer 21

Core enzyme

Question 22

There is one type of RNA polymerase _______ but many kinds of _______

Answer 22

There is one type of RNA polymerase core enzyme but many kinds of sigma-subunits

Question 23

Different ______- recognize promoters with different sequencces

Answer 23

sigma subunit

Question 24

encoded in the DNA sequence appearing as a region of dyad symmetry

Answer 24

Factor-independent termination

Question 25

binds directly to RNA pol and causes the polymerase to stop and release when reaching the factor-dependent termination

Answer 25

Rho factor

Question 26

receptor-dependent termination requires _____ for ______________

Answer 26

Rho factor for transcription termination

Question 27

positive regulator and binds upstream of the promoter

Answer 27

X

Question 28

negative regulator, a represor binding site that can overlap promoter or be downstream of the promoter

Answer 28

Y

Question 29

sigma factor for toxin gene transcription

Answer 29

TcdR

Question 30

antibiotic and toxin production in liquid medium

Answer 30

Stationary- tcdR

Question 31

tcdR is inactivated by ______ in the _______ phase

Answer 31

CodY-Ile is active in the exponential phase

Question 32

tcdR is expressed in the

Answer 32

stationary

Question 33

cody only works a repressor when

Answer 33

isoleucine is bound

Question 34

more isoleucine in the

Answer 34

exponential phase

Question 35

metabolic active phase

Answer 35

exponential

Question 36

CoDY is _____ in stationary phase

Answer 36

inactive

Question 37

CoDY is ______ in exponential phase

Answer 37

active

Question 38

tcdR in nutrient limitation

Answer 38

active and toxins synthesized

Question 39

anti sigma factor

Answer 39

tcdC

Question 40

tcdC binds to ____ and inactivates it

Answer 40

tcdR

Question 41

High toxin production:

a. Mutation in tcdC that inactivates the protein
b. Mutation in tcdR that inactivates the protein
c. Mutation in codY that inactivates the protein
d. Mutation in promoter of tcdB that inactivates the promoter

Answer 41

a. Mutation in tcdC that inactivates the protein

AND

c. Mutation in codY that inactivates the protein