Question

Class I aminoacyl-tRNA synthetases add the aa to the ___'-OH of the terminal adenylate.

A) 2'
B) 3'
C) 4'
D) 5'

Answer 1

Aminoacyl-tRNA synthetases attach the amino acid to the 3'-OH group of the terminal adenylate of tRNA during the charging process.

Step-by-step explanation:

Class I aminoacyl-tRNA synthetases add the amino acid to the 3'-OH of the terminal adenylate. This process is part of tRNA 'charging,' where the enzyme links the correct or cognate amino acid to its corresponding tRNA molecule. By first activating the amino acid with adenosine monophosphate (AMP) and then transferring it to the tRNA, a charged tRNA is produced, and AMP is released. The addition of the amino acid occurs at the 3'-terminal adenosine of the tRNA, specifically at the free 3' –OH group to form an ester bond.