title: [E75, R78 and D82 of Escherichia coli FtsZ are key residues for FtsZ cellular self-assembly and FtsZ-MreB interaction].
abstract: OBJECTIVE
  To explore effects of FtsZ mutants FtsZ(E75A), FtsZ(R78G) and FtsZ(D82A) on FtsZ self-assembly and interaction of FtsZ with MreB in Escherichia coli strains. METHODS) We constructed FtsZ and its mutant's plasmids by molecular clone and site-directed mutagenesis methods, and purified targeted proteins by affinity chromatography. QN6(ftsZ::yfp-cat), QN7(tsZ::yfp-cat), QN8(ftsZ(R78G)::yfp-cat) and QN9 (ftsZ(D82A):.:yfp-cat) strains were constructed by linear DNA homologous recombination. We observed cellular localization pattern of FtsZ and its mutants in E. coli by living cell imaging experiments, examined interaction of FtsZ/FtsZ*-FtsZ* and FtsZ/FtsZ*-MreB by Coimmunoprecipitation and bacteria two hybrid, and analyzed assembly characteristics of FtsZ mutants by Light scattering. RESULTS) The Yfp-labeled FtsZ(E75A), FtsZ(R78G) and FtsZ(D82A) mutant proteins failed to assemble into functional Z-ring structure and localize correctly in E. coli strains. Interaction of FtsZ with its mutants, or FtsZ*-FtsZ* and FtsZ*-MreB interaction were weakened or completely disappeared. In addition, in vitro experiments show that E75A, R78G and D82A mutations decreased the polymerization efficiency of FtsZ monomer.
  
  
  CONCLUSIONS
  FtsZ E75, R78 and D82 are critical amino acids in the assembly, function of FtsZ protein and FtsZ-MreB interaction in E. coli strains.
authors.forename: Yujia
authors.initials: Y
authors.lastname: Huo
authors.forename: Qiaonan
authors.initials: Q
authors.lastname: Lu
authors.forename: Xiaowei
authors.initials: X
authors.lastname: Zheng
authors.forename: Yuanfang
authors.initials: Y
authors.lastname: Ma
authors.forename: Feng
authors.initials: F
authors.lastname: Lu
mesh_terms: D020816:Amino Acid Motifs; D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D003598:Cytoskeletal Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D004926:Escherichia coli / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism*; D020125:Mutation, Missense; D011485:Protein Binding
chemical_list: D001426:Bacterial Proteins; D003598:Cytoskeletal Proteins; D029968:Escherichia coli Proteins; C071525:FtsZ protein, Bacteria; C078473:MreB protein, E coli