title: Structure and mechanism of MT-ADPRase, a nudix hydrolase from Mycobacterium tuberculosis.
abstract: Nudix hydrolases are a family of proteins that contain the characteristic sequence GX(5)EX(7)REUXEEXG(I/L/V), the Nudix box. They catalyze the hydrolysis of a variety of nucleoside diphosphate derivatives such as ADP-ribose, Ap(n)A (3 </= n </= 6), NADH, and dATP. A number of Nudix hydrolases from several species, ranging from bacteria to humans, have been characterized, including, in some cases, the determination of their three-dimensional structures. The product of the Rv1700 gene of M. tuberculosis is a Nudix hydrolase specific for ADP-ribose (ADPR). We have determined the crystal structures of MT-ADPRase alone, and in complex with substrate, with substrate and the nonactivating metal ion Gd(3+), and in complex with a nonhydrolyzable ADPR analog and the activating metal ion Mn(2+). These structures, refined with data extending to resolutions between 2.0 and 2.3 A, showed that there are sequence differences in binding site residues between MT-ADPRase and a human homolog that may be exploited for antituberculosis drug development.
authors.affiliation: Department of Biophysics and Biophysical Chemistry, Johns Hopkins School of Medicine, Baltimore, MD 21205, USA.
authors.forename: Lin-Woo
authors.initials: LW
authors.lastname: Kang
authors.forename: Sandra B
authors.initials: SB
authors.lastname: Gabelli
authors.forename: Jennifer E
authors.initials: JE
authors.lastname: Cunningham
authors.forename: Suzanne F
authors.initials: SF
authors.lastname: O'Handley
authors.forename: L Mario
authors.initials: LM
authors.lastname: Amzel
mesh_terms: D000246:Adenosine Diphosphate Ribose / Q000378:metabolism; D000595:Amino Acid Sequence; D001665:Binding Sites; D002384:Catalysis; D018360:Crystallography, X-Ray; D019281:Dimerization; D004789:Enzyme Activation; D004926:Escherichia coli / Q000201:enzymology; D005682:Gadolinium / Q000378:metabolism; D018257:Helix-Loop-Helix Motifs; D006801:Humans; D006860:Hydrogen Bonding; D006867:Hydrolases / Q000737:chemistry*; D008024:Ligands; D008345:Manganese / Q000378:metabolism; D008958:Models, Molecular; D008969:Molecular Sequence Data; D015394:Molecular Structure; D009169:Mycobacterium tuberculosis / Q000201:enzymology* / Q000235:genetics; D011487:Protein Conformation; D017434:Protein Structure, Tertiary; D011755:Pyrophosphatases / Q000737:chemistry*; D017386:Sequence Homology, Amino Acid; D013045:Species Specificity; D013379:Substrate Specificity; D014867:Water / Q000737:chemistry
chemical_list: D008024:Ligands; D014867:Water; D000246:Adenosine Diphosphate Ribose; D008345:Manganese; D005682:Gadolinium; D006867:Hydrolases; D011755:Pyrophosphatases