title: The Soluble Periplasmic Domains of Escherichia coli Cell Division Proteins FtsQ/FtsB/FtsL Form a Trimeric Complex with Submicromolar Affinity.
abstract: Cell division in Escherichia coli involves a set of essential proteins that assembles at midcell to form the so-called divisome. The divisome regulates the invagination of the inner membrane, cell wall synthesis, and inward growth of the outer membrane. One of the divisome proteins, FtsQ, plays a central but enigmatic role in cell division. This protein associates with FtsB and FtsL, which, like FtsQ, are bitopic inner membrane proteins with a large periplasmic domain (denoted FtsQp, FtsBp, and FtsLp) that is indispensable for the function of each protein. Considering the vital nature and accessible location of the FtsQBL complex, it is an attractive target for protein-protein interaction inhibitors intended to block bacterial cell division. In this study, we expressed FtsQp, FtsBp, and FtsLp individually and in combination. Upon co-expression, FtsQp was co-purified with FtsBp and FtsLp from E. coli extracts as a stable trimeric complex. FtsBp was also shown to interact with FtsQp in the absence of FtsLp albeit with lower affinity. Interactions were mapped at the C terminus of the respective domains by site-specific cross-linking. The binding affinity and 1:1:1 stoichiometry of the FtsQpBpLp complex and the FtsQpBp subcomplex were determined in complementary surface plasmon resonance, analytical ultracentrifugation, and native mass spectrometry experiments.
authors.affiliation: From the Amsterdam Institute of Molecules, Medicines and Systems, VU University Amsterdam, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands.
authors.forename: Marjolein
authors.initials: M
authors.lastname: Glas
authors.affiliation: From the Amsterdam Institute of Molecules, Medicines and Systems, VU University Amsterdam, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands.
authors.forename: H Bart
authors.initials: HB
authors.lastname: van den Berg van Saparoea
authors.affiliation: the Medical Research Council Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, United Kingdom.
authors.forename: Stephen H
authors.initials: SH
authors.lastname: McLaughlin
authors.affiliation: the Swammerdam Institute for Life Sciences, Department of Mass Spectrometry of Biomacromolecules, and.
authors.forename: Winfried
authors.initials: W
authors.lastname: Roseboom
authors.affiliation: the Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, 3584 CH Utrecht, The Netherlands, and.
authors.forename: Fan
authors.initials: F
authors.lastname: Liu
authors.affiliation: From the Amsterdam Institute of Molecules, Medicines and Systems, VU University Amsterdam, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands.
authors.forename: Gregory M
authors.initials: GM
authors.lastname: Koningstein
authors.affiliation: the NKI Protein Facility, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands.
authors.forename: Alexander
authors.initials: A
authors.lastname: Fish
authors.affiliation: Swammerdam Institute for Life Sciences, Department of Bacterial Cell Biology, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands.
authors.forename: Tanneke
authors.initials: T
authors.lastname: den Blaauwen
authors.affiliation: the Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, 3584 CH Utrecht, The Netherlands, and.
authors.forename: Albert J R
authors.initials: AJ
authors.lastname: Heck
authors.affiliation: the Swammerdam Institute for Life Sciences, Department of Mass Spectrometry of Biomacromolecules, and.
authors.forename: Luitzen
authors.initials: L
authors.lastname: de Jong
authors.affiliation: From the Amsterdam Institute of Molecules, Medicines and Systems, VU University Amsterdam, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands.
authors.forename: Wilbert
authors.initials: W
authors.lastname: Bitter
authors.affiliation: From the Amsterdam Institute of Molecules, Medicines and Systems, VU University Amsterdam, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands.
authors.forename: Iwan J P
authors.initials: IJ
authors.lastname: de Esch
authors.affiliation: From the Amsterdam Institute of Molecules, Medicines and Systems, VU University Amsterdam, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands, s.luirink@vu.nl.
authors.forename: Joen
authors.initials: J
authors.lastname: Luirink
mesh_terms: D000595:Amino Acid Sequence; D015374:Biosensing Techniques; D018797:Cell Cycle Proteins / Q000737:chemistry / Q000378:metabolism; D002455:Cell Division; D003432:Cross-Linking Reagents / Q000378:metabolism; D004926:Escherichia coli / Q000166:cytology* / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000737:chemistry* / Q000378:metabolism*; D055767:Immobilized Proteins / Q000378:metabolism; D008027:Light; D013058:Mass Spectrometry; D008565:Membrane Proteins / Q000737:chemistry / Q000378:metabolism; D008958:Models, Molecular; D008969:Molecular Sequence Data; D008970:Molecular Weight; D046912:Multiprotein Complexes / Q000378:metabolism*; D010455:Peptides / Q000737:chemistry / Q000378:metabolism; D019897:Periplasm / Q000378:metabolism; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D021122:Protein Subunits / Q000737:chemistry / Q000378:metabolism; D012995:Solubility; D013329:Structure-Activity Relationship; D014461:Ultracentrifugation
chemical_list: D018797:Cell Cycle Proteins; D003432:Cross-Linking Reagents; D029968:Escherichia coli Proteins; C456028:FtsB protein, E coli; C068023:FtsQ protein, E coli; D055767:Immobilized Proteins; D008565:Membrane Proteins; D046912:Multiprotein Complexes; D010455:Peptides; D021122:Protein Subunits; C078387:ftsL protein, E coli
keywords: Escherichia coli (E. coli); analytical ultracentrifugation; cell division; mass spectrometry (MS); protein cross-linking; protein-protein interaction; surface plasmon resonance (SPR)