title: Preliminary crystallographic analysis of recombinant VapBC-15 toxin-antitoxin complex from Mycobacterium tuberculosis.
abstract: The Mycobacterium tuberculosis vapBC15 locus encodes a toxin-antitoxin complex. VapC-15 is a toxin and possesses ribonuclease activity and VapB-15 is an antitoxin which both binds and inhibits the VapC-15 toxin. In this study, vapBC15 genes were cloned and co-expressed in Escherichia coli. The complex was purified to homogeneity by affinity and size-exclusion chromatography. The VapBC-15 complex was crystallized using the sitting-drop vapour-diffusion technique. The crystals diffracted to 2.6 Å resolution and belonged to space group P2(1)2(1)2(1), with unit-cell parameters a = 85.63, b = 139.09, c = 148.86 Å. The self-rotation function combined with Matthews coefficient and solvent-content calculations suggests the presence of either six or eight molecules of the complex in the asymmetric unit.
authors.affiliation: Department of Biophysics, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Uddipan
authors.initials: U
authors.lastname: Das
authors.forename: Nitesh
authors.initials: N
authors.lastname: Kumar
authors.forename: Samudrala
authors.initials: S
authors.lastname: Gourinath
authors.forename: Alagiri
authors.initials: A
authors.lastname: Srinivasan
mesh_terms: D000992:Antitoxins / Q000737:chemistry*; D001426:Bacterial Proteins / Q000737:chemistry*; D001427:Bacterial Toxins / Q000737:chemistry*; D002850:Chromatography, Gel; D003460:Crystallization; D018360:Crystallography, X-Ray; D004591:Electrophoresis, Polyacrylamide Gel; D009169:Mycobacterium tuberculosis / Q000378:metabolism*; D011994:Recombinant Proteins / Q000737:chemistry*
chemical_list: D000992:Antitoxins; D001426:Bacterial Proteins; D001427:Bacterial Toxins; D011994:Recombinant Proteins
keywords: Mycobacterium tuberculosis; VapBC-15; ribonucleases; toxin–antitoxin