title: A thermostable non-xylanolytic alpha-glucuronidase of Thermotoga maritima MSB8.
abstract: A putative alpha-glucosidase belonging to glycosyl hydrolase family 4 of Thermotoga maritima (TM0752) was expressed in Escherichia coli and it was found that the recombinant protein (Agu4B) was a p-nitrophenyl alpha-D-glucuronopyranoside hydrolyzing alpha-glucuronidase, not alpha-glucosidase. It did not hydrolyze 4-O-methyl-D-glucuronoxylan or its fragment oligosaccharides. Agu4B was thermostable with an optimum temperature of 80 degrees C. It strictly required Mn(2+) and thiol compounds for its activity. The presence of NAD(+) slightly activated the enzyme. The amino acid sequence of Agu4B showed higher identity with Agu4A (another alpha-glucuronidase of T. maritima, 61%) than with AglA (alpha-glucosidase of T. maritima, 48%).
authors.affiliation: Enzyme Laboratory, National Food Research Institute, Tsukuba, Ibaraki, Japan.
authors.forename: Cuddapah
authors.initials: C
authors.lastname: Suresh
authors.forename: Motomitsu
authors.initials: M
authors.lastname: Kitaoka
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Hayashi
mesh_terms: D000595:Amino Acid Sequence; D017124:Conserved Sequence; D004795:Enzyme Stability; D006026:Glycoside Hydrolases / Q000737:chemistry / Q000378:metabolism*; D006358:Hot Temperature; D007700:Kinetics; D008969:Molecular Sequence Data; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D013379:Substrate Specificity; D013816:Thermodynamics; D020124:Thermotoga maritima / Q000201:enzymology*; D014990:Xylans / Q000378:metabolism
chemical_list: D014990:Xylans; D006026:Glycoside Hydrolases; C096734:alpha-glucuronidase