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  • Characterization of the thermophilic xylanase Fsa02490Xyn from the hyperthermophile Fervidibacter sacchari belonging to glycoside hydrolase family 10
Title: Characterization of the thermophilic xylanase Fsa02490Xyn from the hyperthermophile Fervidibacter sacchari belonging to glycoside hydrolase family 10
Fervidibacter sacchariis an aerobic hyperthermophile belonging to the phylumArmatimonadotathat degrades a variety of polysaccharides. Its genome encodes 117 enzymes with one or more annotated glycoside hydrolase (GH) domain, but the roles of these putative GHs in polysaccharide catabolism are poorly defined. Here, we describe oneF. saccharienzyme encoding a GH10 domain, Fsa02490Xyn, that was previously shown to be active onMiscanthus, oat β‐glucan, and beech‐wood xylan, with optimal activity at 90–100 °C. We show that Fsa02490Xyn is also active on birch‐wood xylan and gellan gum. The pH range on beech‐wood xylan was 4.5 to 9.5 (pHopt7.0–8.0). Fsa024940Xyn had aKmof 2.375 mm,Vmaxof 1250 μm·min−1, andkcat/Kmof 1.259 × 104 s−1·m−1when using apara‐nitrophenyl‐𝛽‐xylobioside assay. A phylogenetic analysis of GH10 family enzymes revealed a large clade of enzymes from diverse members of the classFervidibacteria, including Fsa02490Xyn and a second enzyme fromF. sacchari, with apparent horizontal gene transfer withinFervidibacteriaand betweenFervidibacteriaand thermophilicBacillota. This study establishes Fsa02490Xyn as a hyperthermophilic GH10 enzyme with endo‐β‐1,4‐xylanase activity and identifies a large clade of homologous GH10 enzymes within the classFervidibacteria. Impact statementThe depolymerization of xylan at high temperatures is important because this process limits the degradation of polysaccharides in nature and the synthesis of biofuels from plant wastes. Our study is also important becauseF. sacchariis one of only a few cultivated members of theArmatimonadota, which are polysaccharide‐degradation specialists.  more » « less
Award ID(s):
1757316 2244087
PAR ID:
10650800
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
John Wiley & Sons Ltd.
Date Published:
Journal Name:
FEBS Open Bio
Volume:
15
Issue:
10
ISSN:
2211-5463
Page Range / eLocation ID:
1629 to 1642
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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