PBP5+(dacA)

__**PBP5 (dacA)**__

PBP5 is a low molecular mass (LMM) penicillin binding protein (PBP). It is the most abundant carboxypeptidase of E.coli. However, it is highly specific and only cleaves the terminal D-alanine-D-alanine bond. This makes the stem peptide unavailable for transpeptidation.

Its sequence is homologous to PBP6 and PBP6b, both of which also function as strict carboxypeptidases.

__**Structure:**__

Nicola et al have reported the structure of //E. coli// PBP5 in a complex with the substrate-like peptide boronic acid.