title: Activity of penicillin-binding protein 3 from Escherichia coli.
abstract: The activity of penicillin-binding protein 3 of Escherichia coli has been studied both in vivo and in ether-permeabilized cells. The peptidoglycan transpeptidase activity of penicillin-binding protein 3 appears to use either nascent or exogenously added UDP-N-acetylmuramyl tripeptide-derived substrates as acceptors. By means of a defilamentation system which elicited the activity of penicillin-binding protein 3 in vivo, the structure of peptidoglycan made by this enzyme has been elucidated. This peptidoglycan, very probably of septal location, contained increased amounts of cross-linked peptidoglycan as well as a higher ratio of tripeptide-containing cross-linked subunits.
mesh_terms: D000217:Acyltransferases / Q000378:metabolism*; D001398:Aztreonam / Q000378:metabolism / Q000494:pharmacology; D001426:Bacterial Proteins; D002352:Carrier Proteins; D003523:Cycloserine / Q000494:pharmacology; D004926:Escherichia coli / Q000032:analysis / Q000187:drug effects / Q000201:enzymology*; D029968:Escherichia coli Proteins; D006602:Hexosyltransferases / Q000378:metabolism*; D009097:Multienzyme Complexes / Q000378:metabolism*; D002267:Muramoylpentapeptide Carboxypeptidase; D046915:Penicillin-Binding Proteins; D010457:Peptidoglycan / Q000032:analysis / Q000096:biosynthesis*; D046928:Peptidoglycan Glycosyltransferase; D010458:Peptidyl Transferases / Q000378:metabolism*; D013696:Temperature
chemical_list: D001426:Bacterial Proteins; D002352:Carrier Proteins; D029968:Escherichia coli Proteins; C478704:FtsI protein, E coli; D009097:Multienzyme Complexes; D046915:Penicillin-Binding Proteins; D010457:Peptidoglycan; D003523:Cycloserine; D000217:Acyltransferases; D010458:Peptidyl Transferases; D006602:Hexosyltransferases; D046928:Peptidoglycan Glycosyltransferase; D002267:Muramoylpentapeptide Carboxypeptidase; D001398:Aztreonam