title: Mycobacterium tuberculosis cell division protein, FtsE, is an ATPase in dimeric form.
abstract: FtsE is one of the earliest cell division proteins that assembles along with FtsX at the mid-cell site during cell division in Escherichia coli. Both these proteins are highly conserved across diverse bacterial genera and are predicted to constitute an ABC transporter type complex, in which FtsE is predicted to bind ATP and hydrolyse it, and FtsX is predicted to be an integral membrane protein. We had earlier reported that the MtFtsE of the human pathogen, Mycobacterium tuberculosis, binds ATP and interacts with MtFtsX on the cell membrane of M. tuberculosis and E. coli. In this study, we demonstrate that MtFtsE is an ATPase, the active form of which is a dimer, wherein the participating monomers are held together by non-covalent interactions, with the Cys84 of each monomer present at the dimer interface. Under oxidising environment, the dimer gets stabilised by the formation of Cys84-Cys84 disulphide bond. While the recombinant MtFtsE forms a dimer on the membrane of E. coli, the native MtFtsE seems to be in a different conformation in the M. tuberculosis membrane. Although disulphide bridges were not observed on the cytoplasmic side (reducing environment) of the membrane, the two participating monomers could be isolated as dimers held together by non-covalent interactions. Taken together, these findings show that MtFtsE is an ATPase in the non-covalent dimer form, with the Cys84 of each monomer present in the reduced form at the dimer interface, without participating in the dimerisation or the catalytic activity of the protein.
authors.affiliation: Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore, 560012, India.
authors.forename: Mushtaq Ahmad
authors.initials: MA
authors.lastname: Mir
authors.forename: Muthu
authors.initials: M
authors.lastname: Arumugam
authors.forename: Sukanta
authors.initials: S
authors.lastname: Mondal
authors.forename: Haryadi S
authors.initials: HS
authors.lastname: Rajeswari
authors.forename: Suryanarayanarao
authors.initials: S
authors.lastname: Ramakumar
authors.forename: Parthasarathi
authors.initials: P
authors.lastname: Ajitkumar
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D000251:Adenosine Triphosphatases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D018797:Cell Cycle Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D002462:Cell Membrane / Q000201:enzymology* / Q000235:genetics; D006801:Humans; D009169:Mycobacterium tuberculosis / Q000201:enzymology* / Q000235:genetics; D010084:Oxidation-Reduction; D055503:Protein Multimerization
chemical_list: D018528:ATP-Binding Cassette Transporters; D001426:Bacterial Proteins; D018797:Cell Cycle Proteins; C102286:FtsX protein, bacteria; D000251:Adenosine Triphosphatases