4anc

CRYSTAL FORM I OF THE D93N MUTANT OF NUCLEOSIDE DIPHOSPHATE KINASE FROM MYCOBACTERIUM TUBERCULOSISCRYSTAL FORM I OF THE D93N MUTANT OF NUCLEOSIDE DIPHOSPHATE KINASE FROM MYCOBACTERIUM TUBERCULOSIS

Structural highlights 4anc is a 1 chain structure with sequence from Mycobacterium tuberculosis. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Method: X-ray diffraction, Resolution 2.8Å Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Function NDK_MYCTU Major role in the synthesis of nucleoside triphosphates other than ATP.[HAMAP-Rule:MF_00451] Publication Abstract from PubMed Most nucleoside diphosphate kinases (NDPKs) are hexamers. The C-terminal tail interacting with the neighboring subunits is crucial for hexamer stability. In the NDPK from Mycobacterium tuberculosis (Mt) this tail is missing. The quaternary structure of Mt-NDPK is essential for full enzymatic activity and for protein stability to thermal and chemical denaturation. We identified the intersubunit salt bridge Arg(80)-Asp(93) as essential for hexamer stability, compensating for the decreased intersubunit contact area. Breaking the salt bridge by the mutation D93N dramatically decreased protein thermal stability. The mutation also decreased stability to denaturation by urea and guanidinium. The D93N mutant was still hexameric and retained full activity. When exposed to low concentrations of urea it dissociated into folded monomers followed by unfolding while dissociation and unfolding of the wild type simultaneously occur at higher urea concentrations. The dissociation step was not observed in guanidine hydrochloride, suggesting that low concentration of salt may stabilize the hexamer. Indeed, guanidinium and many other salts stabilized the hexamer with a half maximum effect of about 0.1 M, increasing protein thermostability. The crystal structure of the D93N mutant has been solved. Intersubunit Ionic Interactions Stabilize the Nucleoside Diphosphate Kinase of Mycobacterium tuberculosis.,Georgescauld F, Moynie L, Habersetzer J, Cervoni L, Mocan I, Borza T, Harris P, Dautant A, Lascu I PLoS One. 2013;8(3):e57867. doi: 10.1371/journal.pone.0057867. Epub 2013 Mar 5. PMID:23526954 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See Also Nucleoside diphosphate kinase 3D structures

spinqualitylabelsall models 4anc, resolution 2.80Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image