title: DD-carboxypeptidase and peptidoglycan transpeptidase from Pseudomonas aeruginosa.
abstract: Peptidoglycan transpeptidase and dd-carboxypeptidase have been detected in isolated membranes of Pseudomonas aeruginosa. Cephalosporins and penicillins fail to inhibit the transpeptidase at concentrations as high as 100 mug/ml. dd-Carboxypeptidase, on the other hand, is sensitive to inhibition by beta-lactam antibiotics. The presence of dimethyl sulfoxide in the reaction mixture results in a twofold stimulation of peptidoglycan formation, whereas dd-carboxypeptidase is inhibited approximately 30%. Maximum stimulation of transpeptidase occurs in the presence of both dimethyl sulfoxide and a beta-lactum antibiotic. This is in sharp contrast to the transpeptidase from Escherichia coli, which is sensitive to inhibition by penicillins and cephalosporins.
mesh_terms: D000217:Acyltransferases / Q000378:metabolism*; D002268:Carboxypeptidases / Q000378:metabolism*; D004121:Dimethyl Sulfoxide / Q000494:pharmacology; D010457:Peptidoglycan; D010458:Peptidyl Transferases / Q000378:metabolism*; D011550:Pseudomonas aeruginosa / Q000187:drug effects / Q000201:enzymology*
chemical_list: D010457:Peptidoglycan; D000217:Acyltransferases; D010458:Peptidyl Transferases; D002268:Carboxypeptidases; D004121:Dimethyl Sulfoxide