Chapter 12 part 3

Question 1

Under heat stress, E.coli use _______ to activate expression of specialized heat stress response

Answer 1

alternative sigma factors

Question 2

under heat stress, specialized ________ encode for proteins that protect cells from certain types of heat-induced damage

Answer 2

heat shock genes

Question 3

At high temperatures, the usual sigma factor, 70, is unstable and the alternative one , _______, is used, which transcribes heat shock genes

Answer 3

sigma factor 32

Question 4

The gene _______ encodes for sigma factor 32

Answer 4

rpoH

Question 5

a second consequence of the high temperatures is the change in _______ proteins (from sigma 32 destructive to heat damaged protein destructive)

Answer 5

chaperone proteins

Question 6

What are the 2 ways that bacteria undergo translational regulation? (not very common)

Answer 6

1) translation repressor proteins
2) antisense RNA

Question 7

IS 10 regulation is an example of _______

Answer 7

antisense RNA

Question 8

IS10 insertion sequece contins two promotors:

Answer 8

1) Pin - directs transcription of transposase
2) Pout - directs transcription of antisense RNA which binds to transposase gene and leads to degradation

Question 9

Which is stronger, Pin or Pout?

Answer 9

Pout

Question 10

a _______ is where an mRNA binds a small regulatory molecule

Answer 10

riboswitch

Question 11

What are the 3 ways that riboswitches can regulate proteins?

Answer 11

1) transcription
2) translation
3) mRNA stability

Question 12

A riboswitch regulates transcription of the _______ operon, which codes for proteins of the biosynthetic pathway for thiamin pyrophosphate production

Answer 12

thiamin (thi) operon

Question 13

With low TPP concentration, TPP amounts are too low for riboswitch binding, leading to the formation of _______, which allows transcription of operon genes

bacillus subtilis

Answer 13

antitermination stem-loop

Question 14

With high TPP concentration, TPP binds to riboswitch generating _______ followed by poly-U sequence

bacillus subtilis

Answer 14

termination stem-loop

Question 15

With low TPP concentration, 5’UTR of the mRNA forms a secondary sequence that contains the shine-delgarno _______
- translation occurs

E.coli

Answer 15

antisequestor stemloop

Question 16

With high TPP concentration, TPP binds to the riboswitch inducing the formation of an mRNA stem loop that prevents the shine delgarno sequence and start codon from initiating _______

E.coli

Answer 16

translation

Question 17

In B. subtilus, the gene _______ codes for the enzyme glutamine: fructose-6-phosphate aminotransferase, which is involved in the production of the sugar _______

Answer 17

1) glmS
2) GlcN6P

Question 18

explain riboswitch control based on [GlcN6P]

Answer 18

• when [GlcN6P] low glmS is expressed
• when [GlcN6P] high, it binds to riboswitch sequence on glms leading to mRNA cleaving