title: A lacZ-pbpB gene fusion coding for an inducible hybrid protein that recognizes localized sites in the inner membrane of Escherichia coli.
abstract: An in-phase gene fusion consisting of the 5'-terminal 1,314 base pairs (bp) of the structural gene for beta-galactosidase (lacZ) and the 3'-terminal 1,644 bp of the structural gene coding for penicillin-binding protein 3 (pbpB) of Escherichia coli was constructed and cloned in the plasmid pDIAM64. The product of the fusion gene was a remarkably stable protein with an apparent molecular weight of 110,000 (p110) that retained the ability to covalently interact with beta-lactam antibiotics. The fusion protein was found associated with the membrane at low levels of induction, but it accumulated in the cytoplasm of cells induced for a long time as inclusion bodies of high density. Inclusion bodies were localized at defined positions corresponding to septal sites in all of the pDIAM64-containing strains tested except PAT84 and GD113 (which carry the ftsZ84 mutant allele). These findings indicate a possible role of the FtsZ protein in the integration of Pbp3 into the membrane and in septum localization during the cell division cycle.
mesh_terms: D000217:Acyltransferases / Q000235:genetics*; D000900:Anti-Bacterial Agents / Q000378:metabolism; D001426:Bacterial Proteins; D002352:Carrier Proteins; D002455:Cell Division; D002462:Cell Membrane / Q000378:metabolism; D003001:Cloning, Molecular; D004591:Electrophoresis, Polyacrylamide Gel; D004926:Escherichia coli / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism / Q000648:ultrastructure; D029968:Escherichia coli Proteins; D005696:Galactosidases / Q000235:genetics*; D005786:Gene Expression Regulation; D005796:Genes; D005798:Genes, Bacterial; D005822:Genetic Vectors; D006602:Hexosyltransferases / Q000235:genetics*; D007700:Kinetics; D007769:Lactams; D008854:Microscopy, Electron; D008858:Microscopy, Phase-Contrast; D009097:Multienzyme Complexes / Q000235:genetics*; D002267:Muramoylpentapeptide Carboxypeptidase; D046915:Penicillin-Binding Proteins; D046928:Peptidoglycan Glycosyltransferase; D010458:Peptidyl Transferases / Q000235:genetics*; D010957:Plasmids; D011993:Recombinant Fusion Proteins / Q000235:genetics* / Q000378:metabolism; D011994:Recombinant Proteins / Q000235:genetics*; D001616:beta-Galactosidase / Q000235:genetics*
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D002352:Carrier Proteins; D029968:Escherichia coli Proteins; C478704:FtsI protein, E coli; D007769:Lactams; D009097:Multienzyme Complexes; D046915:Penicillin-Binding Proteins; D011993:Recombinant Fusion Proteins; D011994:Recombinant Proteins; D000217:Acyltransferases; D010458:Peptidyl Transferases; D006602:Hexosyltransferases; D046928:Peptidoglycan Glycosyltransferase; D005696:Galactosidases; D001616:beta-Galactosidase; D002267:Muramoylpentapeptide Carboxypeptidase