Protein synthesis 2 prokaryotes Flashcards
1
Q
What is the tRNA that always incorporates in the first methionine?
A
tRNA^fmet
2
Q
What is the Shine-Dalgarno sequence in ?
A
A purine rich sequence 10 nucleotides upstream from the official start codon: used by ribosome to determine the start codon.
3
Q
What is the role of IF3?
A
It recognizes the 30s portion of the ribosome, preventing the 30s from binding to the 50s portion of the ribosome, and causes the 30s to bind to mRNA.
4
Q
What is the role of IF2?
A
binds a GTP and tRNA^fmet, allowing the tRNA^fmet to position itself on the P site of the ribosome.
5
Q
What occurs when the 50s portion of the ribosome joins the 30s bound to the mRNA ?
A
The GTP attached to the first tRNA is hydrolyzed. Then IF1 and 3 are released
