translation initiation in bacteria

Question 1

waht is the goal of translation initiation?

Answer 1

to build a initiator tRNA in the Psite matched to the start codon on the mRNA which is positioned so that the A site is ready to accept a new aa-tRNA

Question 2

what are the trasnlation factors?

Answer 2

Bacteria:
Initiation - 3
Elongation - 3
Termination 4(6)
Eukaryotes:
Initiation - 11
Elongation - 3
Termination 3(6)

Question 3

what do IF1 and IF3 do?

Answer 3

bind to the small subunit preventing the large subunit from associating they also block sites A and E

Question 4

what are the ways IF2 and the initiator tRNA bind?

Answer 4

Initiator base paired with the start codon first
IF2 binds with the small subunit an facilitates the association of initiator tRNA
Both bind at the same time

Question 5

what is the shine dalgarno sequence and what does it do?

Answer 5

AGGAGGU
Pairs in the 16S rRNA region
Guides the initiator UAG into the P site

Question 6

what happens once the tRNA and mRNA are in place?

Answer 6

hydrolysis of the GTP on IF2 facilitates and is essential for dissociation if IF1, IF2 and IF3 but IF2 is a latent GTPase

Question 7

what do antibiotics do?

Answer 7

inhibit steps of translation