4chg

Crystal structure of VapBC15 complex from Mycobacterium tuberculosis

spinqualitylabelsall models 4chg, resolution 2.10Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image   Print3D Structural highlights 4chg is a 10 chain structure with sequence from Myctu. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Ligands: MG, MN NonStd Res: MSE Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Function [VPC15_MYCTU] Toxic component of a toxin-antitoxin (TA) module. An RNase (By similarity). Upon expression in M.smegmatis inhibits colony formation. Its toxic effect is neutralized by coexpression with cognate antitoxin VapB15.[HAMAP-Rule:MF_00265] [VPB15_MYCTU] Antitoxin component of a toxin-antitoxin (TA) module. Upon expression in M.smegmatis neutralizes the effect of cognate toxin VapC15. Publication Abstract from PubMed Although PIN (PilT N-terminal)-domain proteins are known to have ribonuclease activity, their specific mechanism of action remains unknown. VapCs form a family of ribonucleases that possess a PIN-domain assembly and are known as toxins. The activities of VapCs are impaired by VapB antitoxins. Here we present the crystal structure of the VapBC-15 toxin-antitoxin complex from Mycobacterium tuberculosis determined to 2.1A resolution. The VapB-15 and VapC-15 components assemble into one heterotetramer (VapB2C2) and two heterotrimers (VapBC2) in each asymmetric unit of the crystal. The active site of VapC-15 toxin consists of a cluster of acidic amino acid residues and two divalent metal ions, forming a well organised ribonuclease active site. The distribution of the catalytic-site residues of the VapC-15 toxin is similar to that of T4 RNase H and of Methanococcus jannaschii FEN-1, providing strong evidence that these three proteins share a similar mechanism of activity. The presence of both VapB2C2 and VapBC2 emphasizes the fact that the same antitoxin can bind the toxin in 1:1 and 1:2 ratios. The crystal structure determination of the VapBC-15 complex reveals for the first time a PIN-domain ribonuclease protein that shows two metal ions at the active site and a variable mode of toxin-antitoxin assembly. The structure further shows that VapB-15 antitoxin binds to the same groove meant for the binding of putative substrate (RNA), resulting in the inhibition of VapC-15's toxicity. Crystal structure of the VapBC-15 complex from Mycobacterium tuberculosis reveals a two-metal ion dependent PIN-domain ribonuclease and a variable mode of toxin-antitoxin assembly.,Das U, Pogenberg V, Subhramanyam UK, Wilmanns M, Gourinath S, Srinivasan A J Struct Biol. 2014 Oct 22;188(3):249-258. doi: 10.1016/j.jsb.2014.10.002. PMID:25450593 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

Proteopedia Page Contributors and Editors (what is this?)

OCA