Final answer:
During tRNA charging, the intermediate formed is Acyl adenylate. It is formed as aminoacyl-tRNA synthetase catalyzes the attachment of an amino acid to AMP, before the amino acid is eventually transferred to the tRNA molecule.
Step-by-step explanation:
During the charging of a tRNA, the intermediate that is formed is Acyl adenylate. This occurs in a multi-step process where an amino acid is first activated by the attachment of adenosine monophosphate (AMP), resulting in what is known as an amino acid-AMP complex. This is followed by the transfer of the activated amino acid to the tRNA molecule.
The enzyme responsible for this process is aminoacyl-tRNA synthetase, which binds the amino acid to ATP, causing it to hydrolyze and form the intermediate before being transferred to the tRNA. When the bond between the amino acid and AMP is high-energy, it drives the formation of the peptide bond during protein synthesis. Thus, in the initial phase of tRNA charging, it is not yet aminoacyl-tRNA, but rather an activated amino acid attached to AMP, which is acyl adenylate (option b).