An amino acid must bind to an aminoacyl-tRNA synthetase enzyme in order to charge a transfer RNA.
Aminoacyl-tRNA synthetases play a crucial role in the process of protein synthesis by ensuring the accurate pairing of amino acids with their corresponding transfer RNAs (tRNAs). In order to charge a tRNA, an amino acid must first bind to the specific aminoacyl-tRNA synthetase enzyme that corresponds to that particular amino acid. Each aminoacyl-tRNA synthetase is specific to its cognate amino acid and recognizes the corresponding tRNA molecule.
The binding of the amino acid to the enzyme triggers the activation and attachment of the amino acid to the appropriate tRNA, forming an aminoacyl-tRNA complex. This charged tRNA can then participate in the ribosomal machinery during translation, facilitating the accurate incorporation of the specific amino acid into the growing polypeptide chain. The stringent specificity of aminoacyl-tRNA synthetases ensures the fidelity of the genetic code translation process in protein synthesis.