Elongation - Prokaryotic

Question 1

Step 1

Answer 1

The second aminoacyl-tRNA enters the A site bound to EF-Tu-GTP complex. Hydrolysis of the GTP to GDP triggers dissociation of this EF-Tu-GDP complex and tRNA can properly bind ribosome.

Question 2

Step 2

Answer 2

A peptidyl transferase moves fMet from fMet-tRNA and transfers it to the amino group of the of the amino acid on the tRNA in the A site. This is the formation of the first peptide bond forming a dipeptidyl tRNA in the P site.

Question 3

Step 3

Answer 3

The ribosome moves to next codon in a 5’ to 3’ prime direction via the hydrolysis of GTP on EF-G translocase. The dipeptidyl tRNA is enitrely in the P site leading the A site open for the next tRNA. The uncharged tRNA in the E site dissociates.