During transpeptidation, nucleophilic attack occurs between the α-amine group in the A site and the esterified carbon in the P site.
What is a transpeptidation?
A chemical process in which an amino acid residue or a peptide residue is transferred from one amino molecule to another (as in the reversible conversion of one peptide to another by a protease).
The binding of transpeptidase PBPs inhibits peptidoglycan production.
Transpeptidase is a bacterial enzyme that cross-links peptidoglycan strands to build stiff cell walls. A liver enzyme called gamma-glutamyl transpeptidase. Transpeptidase D-glutamyl.
To learn more about nucleophilic attacks from the given link