Penicillin amidase, E. coli (Immobilized) (PGA) is an amidohydrolase commonly used in industrial biocatalysis. Penicillin amidase, E. coli (Immobilized) serves as a starting material in the synthesis of semi-synthetic penicillins. Penicillin amidase, E. coli (Immobilized) promotes the production of semi-synthetic β-lactam antibiotics, participates in peptide synthesis, and catalyzes the formation of chiral compounds. Penicillin amidase, E. coli (Immobilized) is regulated by temperature and phenylacetic acid in E. coli. In free E. coli, it participates in the assimilation of aromatic compounds as a carbon source. Penicillin amidase, E. coli (Immobilized) is hypothesized to act as a scavenging enzyme for phenylacetyl-containing compounds in microbial metabolism and is associated with bacterial quorum sensing .