title: An early cytoplasmic step of peptidoglycan synthesis is associated to MreB in Bacillus subtilis.
abstract: MreB proteins play a major role during morphogenesis of rod-shaped bacteria by organizing biosynthesis of the peptidoglycan cell wall. However, the mechanisms underlying this process are not well understood. In Bacillus subtilis, membrane-associated MreB polymers have been shown to be associated to elongation-specific complexes containing transmembrane morphogenetic factors and extracellular cell wall assembly proteins. We have now found that an early intracellular step of cell wall synthesis is also associated to MreB. We show that the previously uncharacterized protein YkuR (renamed DapI) is required for synthesis of meso-diaminopimelate (m-DAP), an essential constituent of the peptidoglycan precursor, and that it physically interacts with MreB. Highly inclined laminated optical sheet microscopy revealed that YkuR forms uniformly distributed foci that exhibit fast motion in the cytoplasm, and are not detected in cells lacking MreB. We propose a model in which soluble MreB organizes intracellular steps of peptidoglycan synthesis in the cytoplasm to feed the membrane-associated cell wall synthesizing machineries.
authors.affiliation: INRA, UMR1319 Micalis, F-78352, Jouy-en-Josas, France; AgroParisTech, UMR1319 Micalis, F-78352, Jouy-en-Josas, France.
authors.forename: Anne-Stéphanie
authors.initials: AS
authors.lastname: Rueff
authors.forename: Arnaud
authors.initials: A
authors.lastname: Chastanet
authors.forename: Julia
authors.initials: J
authors.lastname: Domínguez-Escobar
authors.forename: Zhizhong
authors.initials: Z
authors.lastname: Yao
authors.forename: James
authors.initials: J
authors.lastname: Yates
authors.forename: Maria-Victoria
authors.initials: MV
authors.lastname: Prejean
authors.forename: Olivier
authors.initials: O
authors.lastname: Delumeau
authors.forename: Philippe
authors.initials: P
authors.lastname: Noirot
authors.forename: Roland
authors.initials: R
authors.lastname: Wedlich-Söldner
authors.forename: Sergio R
authors.initials: SR
authors.lastname: Filipe
authors.forename: Rut
authors.initials: R
authors.lastname: Carballido-López
mesh_terms: D001412:Bacillus subtilis / Q000235:genetics / Q000378:metabolism*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D002473:Cell Wall / Q000378:metabolism; D003593:Cytoplasm / Q000378:metabolism*; D008958:Models, Molecular; D009154:Mutation; D010457:Peptidoglycan / Q000096:biosynthesis* / Q000235:genetics; D015398:Signal Transduction
chemical_list: D001426:Bacterial Proteins; D010457:Peptidoglycan