D-alanyl-D-alanine carboxypeptidase, serine-type, PBP4 family
In E. coli, this protein is known as penicillin binding protein 4 (dacB). A signal sequence is cleaved from a precursor form. The protein is described as periplasmic in E. coli (Gram-negative) and extracellular in Actinomadura R39 (Gram-positive). Unlike some other proteins with similar activity, it does not form transpeptidation. It is not essential for viability. This family is related to class A beta-lactamases. [Cell envelope, Biosynthesis and degradation of murein sacculus and peptidoglycan]
Jiyao W et al.(2023). "The conserved domain database in 2023.",