3gnr: Difference between revisions
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<scriptWhenChecked>select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/gn/3gnr_consurf.spt"</scriptWhenChecked> | <scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/gn/3gnr_consurf.spt"</scriptWhenChecked> | ||
<scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked> | <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked> | ||
<text>to colour the structure by Evolutionary Conservation</text> | <text>to colour the structure by Evolutionary Conservation</text> |
Revision as of 08:51, 7 December 2018
Crystal Structure of a Rice Os3BGlu6 Beta-Glucosidase with covalently bound 2-deoxy-2-fluoroglucoside to the catalytic nucleophile E396Crystal Structure of a Rice Os3BGlu6 Beta-Glucosidase with covalently bound 2-deoxy-2-fluoroglucoside to the catalytic nucleophile E396
Structural highlights
Function[BGL06_ORYSJ] Hydrolyzes glycosides, oligosaccharides and hydrophobic glycosides. Evolutionary Conservation![]() Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedGlycoside hydrolase family 1 (GH1) beta-glucosidases play roles in many processes in plants, such as chemical defense, alkaloid metabolism, hydrolysis of cell wall-derived oligosaccharides, phytohormone regulation, and lignification. However, the functions of most of the 34 GH1 gene products in rice (Oryza sativa) are unknown. Os3BGlu6, a rice beta-glucosidase representing a previously uncharacterized phylogenetic cluster of GH1, was produced in recombinant Escherichia coli. Os3BGlu6 hydrolyzed p-nitrophenyl (pNP)-beta-d-fucoside (k(cat)/K(m) = 67 mm(-1) s(-1)), pNP-beta-d-glucoside (k(cat)/K(m) = 6.2 mm(-1) s(-1)), and pNP-beta-d-galactoside (k(cat)/K(m) = 1.6 mm(-1)s(-1)) efficiently but had little activity toward other pNP glycosides. It also had high activity toward n-octyl-beta-d-glucoside and beta-(1-->3)- and beta-(1-->2)-linked disaccharides and was able to hydrolyze apigenin beta-glucoside and several other natural glycosides. Crystal structures of Os3BGlu6 and its complexes with a covalent intermediate, 2-deoxy-2-fluoroglucoside, and a nonhydrolyzable substrate analog, n-octyl-beta-d-thioglucopyranoside, were solved at 1.83, 1.81, and 1.80 A resolution, respectively. The position of the covalently trapped 2-F-glucosyl residue in the enzyme was similar to that in a 2-F-glucosyl intermediate complex of Os3BGlu7 (rice BGlu1). The side chain of methionine-251 in the mouth of the active site appeared to block the binding of extended beta-(1-->4)-linked oligosaccharides and interact with the hydrophobic aglycone of n-octyl-beta-d-thioglucopyranoside. This correlates with the preference of Os3BGlu6 for short oligosaccharides and hydrophobic glycosides. Structural and enzymatic characterization of Os3BGlu6, a rice beta-glucosidase hydrolyzing hydrophobic glycosides and (1->3)- and (1->2)-linked disaccharides.,Seshadri S, Akiyama T, Opassiri R, Kuaprasert B, Cairns JK Plant Physiol. 2009 Sep;151(1):47-58. Epub 2009 Jul 8. PMID:19587102[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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