title: FtsQ, FtsL and FtsI require FtsK, but not FtsN, for co-localization with FtsZ during Escherichia coli cell division.
abstract: During cell division in Gram-negative bacteria, the cell envelope invaginates and constricts at the septum, eventually severing the cell into two compartments, and separating the replicated genetic materials. In Escherichia coli, at least nine essential gene products participate directly in septum formation: FtsA, FtsI, FtsL, FtsK, FtsN, FtsQ, FtsW, FtsZ and ZipA. All nine proteins have been localized to the septal ring, an equatorial ring structure at the division site. We used translational fusions to green fluorescent protein (GFP) to demonstrate that FtsQ, FtsL and FtsI localize to potential division sites in filamentous cells depleted of FtsN, but not in those depleted of FtsK. We also constructed translational fusions of FtsZ, FtsA, FtsQ, FtsL and FtsI to enhanced cyan or yellow fluorescent protein (ECFP or EYFP respectively), GFP variants with different fluorescence spectra. Examination of cells expressing different combinations of the fusions indicated that FtsA, FtsQ, FtsL and FtsI co-localize with FtsZ in filaments depleted of FtsN. These localization results support the model that E. coli cell division proteins assemble sequentially as a multimeric complex at the division site: first FtsZ, then FtsA and ZipA independently of each other, followed successively by FtsK, FtsQ, FtsL, FtsW, FtsI and FtsN.
authors.affiliation: Department of Microbiology and Molecular Genetics, Harvard Medical School, 200 Longwood Avenue, Boston, MA 02115, USA.
authors.forename: J C
authors.initials: JC
authors.lastname: Chen
authors.forename: J
authors.initials: J
authors.lastname: Beckwith
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D002352:Carrier Proteins; D018797:Cell Cycle Proteins; D002455:Cell Division; D003598:Cytoskeletal Proteins; D004926:Escherichia coli / Q000145:classification / Q000166:cytology* / Q000201:enzymology / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism*; D017353:Gene Deletion; D006602:Hexosyltransferases / Q000235:genetics / Q000378:metabolism; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D008856:Microscopy, Fluorescence; D009097:Multienzyme Complexes / Q000235:genetics / Q000378:metabolism; D002267:Muramoylpentapeptide Carboxypeptidase; D016296:Mutagenesis; D046915:Penicillin-Binding Proteins; D046928:Peptidoglycan Glycosyltransferase; D010458:Peptidyl Transferases / Q000235:genetics / Q000378:metabolism; D010957:Plasmids; D021381:Protein Transport
chemical_list: D001426:Bacterial Proteins; D002352:Carrier Proteins; D018797:Cell Cycle Proteins; D003598:Cytoskeletal Proteins; D029968:Escherichia coli Proteins; C478704:FtsI protein, E coli; C096452:FtsK protein, E coli; C098711:FtsN protein, E coli; C068023:FtsQ protein, E coli; C071525:FtsZ protein, Bacteria; D008565:Membrane Proteins; D009097:Multienzyme Complexes; D046915:Penicillin-Binding Proteins; C078387:ftsL protein, E coli; D010458:Peptidyl Transferases; D006602:Hexosyltransferases; D046928:Peptidoglycan Glycosyltransferase; D002267:Muramoylpentapeptide Carboxypeptidase