L5+6- stress response

Question 1

What is the housekeeping sigma factor?

Answer 1

Sigma Factor 70

Question 2

What is the HOLOENZYME?

Answer 2

core enzyme + sigma factor

Question 3

What regions of the promoter so the sigma factor regions 2 and 4 interact with?

Answer 3

-10 and -35

Question 4

What is the stringent response?

Answer 4

shut down of growth and synthesis of rRNA and tRNAs in response to amino acid starvation

Question 5

What are alarmones?

Answer 5

intracellular signalling molecules produced in response to harsh environmental conditions

Question 6

What are the 2 mechanisms used to synthesise alarmones?

Answer 6

RelA-dependent synthesis

SpoT-dependent synthesis

Question 7

Why does protein synthesis stall under amino acid starvation?

Answer 7

uncharged tRNA’s accumulate and bind to ribosome

Question 8

What occurs in RelA dependent synthesis of (p)ppGPP?

Answer 8

stalled protein synthesis triggers RelA to synthesis (p)ppGpp from GTP in a process that utilises ATP

Question 9

What occurs in SpoT-dependent synthesis pf (p)ppGpp”?

Answer 9

fatty acid starvation triggers conformational change in ACP
ACP binds to SpoT
SpoT has active sites that hydrolyse (p)ppGpp