A β‐mannan utilization locus in Bacteroides ovatus involves a GH36 α‐galactosidase active on galactomannans. Issue 14 (28th June 2016)

• Record Type: Journal Article
• Authors: Reddy, Sumitha K.; Bågenholm, Viktoria; Pudlo, Nicholas A.; Bouraoui, Hanene; Koropatkin, Nicole M.; Martens, Eric C.; Stålbrand, Henrik
• Is Part Of: FEBS letters. Volume 590:Issue 14(2016)
• Page Start: 2106
• Page End: 2118
• Publication Date: 2016-06-28
• Subjects: Bacteroides ovatus -- galactomannan modification -- GH36 α‐galactosidase -- polysaccharide utilization locus; Biochemistry -- Periodicals; Biophysics -- Periodicals; Molecular biology -- Periodicals; Biochimie -- Périodiques; Biochemistry; Biophysics; Molecular biology; Periodicals; 572.05
• DOI: 10.1002/1873-3468.12250
• Languages: English
• ISSNs: 0014-5793

Abstract

Abstract : The Bacova_02091 gene in the β‐mannan utilization locus of Bacteroides ovatus encodes a family GH36 α‐galactosidase (BoGal36A), transcriptionally upregulated during growth on galactomannan. Characterization of recombinant BoGal36A reveals unique properties compared to other GH36 α‐galactosidases, which preferentially hydrolyse terminal α‐galactose in raffinose family oligosaccharides. BoGal36A prefers hydrolysing internal galactose substitutions from intact and depolymerized galactomannan. BoGal36A efficiently releases (> 90%) galactose from guar and locust bean galactomannans, resulting in precipitation of the polysaccharides. As compared to other GH36 structures, the BoGal36A 3D model displays a loop deletion, resulting in a wider active site cleft which likely can accommodate a galactose‐substituted polymannose backbone. Abstract :