title: Interaction of FtsA and PBP3 proteins in the Escherichia coli septum.
abstract: Mutations in the ftsA gene of Escherichia coli conferred a higher resistance to lysis induced by penicillin or by a combination of cefsulodin and furazlocillin. The ftsA2 allele codes for an FtsA protein which is inactive at 42 degrees C but is able to regain its activity once it is transferred back to 30 degrees C; ftsA2 filaments formed at 42 degrees C in the presence of penicillin divided once the penicillin was removed and the temperature was lowered to 30 degrees C. Potential septation sites in the filaments of wild-type cells treated in the same way remained inactive. The binding of a radioactively labeled derivative of ampicillin to penicillin-binding protein 3 (PBP3) was significantly decreased in strain D-3, containing the mutant allele ftsA3, when the binding assay was performed at the restrictive temperature. A molecular species able to cross-react with an anti-PBP3 serum was nevertheless found to be present in the envelope of D-3 cells. These observations suggested that the FtsA protein, a protein with a structural and regulatory role in septation, and PBP3, a protein enzymatically active in the synthesis of murein for septation, interact with each other.
mesh_terms: D000483:Alleles; D000667:Ampicillin / Q000378:metabolism; D001390:Azlocillin / Q000031:analogs & derivatives / Q000494:pharmacology; D001426:Bacterial Proteins / Q000235:genetics*; D002352:Carrier Proteins / Q000378:metabolism; D002441:Cefsulodin / Q000494:pharmacology; D004926:Escherichia coli / Q000187:drug effects / Q000235:genetics* / Q000648:ultrastructure; D029968:Escherichia coli Proteins; D006602:Hexosyltransferases; D048289:Imidazolidines; D002267:Muramoylpentapeptide Carboxypeptidase / Q000378:metabolism; D009154:Mutation; D046915:Penicillin-Binding Proteins; D010406:Penicillins / Q000494:pharmacology; D046928:Peptidoglycan Glycosyltransferase; D010458:Peptidyl Transferases; D013696:Temperature
chemical_list: D001426:Bacterial Proteins; D002352:Carrier Proteins; D029968:Escherichia coli Proteins; C478704:FtsI protein, E coli; D048289:Imidazolidines; D046915:Penicillin-Binding Proteins; D010406:Penicillins; D000667:Ampicillin; D010458:Peptidyl Transferases; D006602:Hexosyltransferases; D046928:Peptidoglycan Glycosyltransferase; D002267:Muramoylpentapeptide Carboxypeptidase; D001390:Azlocillin; C017976:furazlocillin; D002441:Cefsulodin