title: Microbial exo-xylanases: a mini review.
abstract: Exo-xylanases are a class of glycosyl hydrolases and play an important role in hydrolysis of xylan to xylose. They belong to glycosyl hydrolase (GH) family 8 with a characteristic (α/α)6 barrel fold in their molecular structures. These enzymes are generally produced by bacteria. Exceptionally, the endo-xylanases from Trichoderma reesei Rut C-30 and a few bacterial strains also show considerable exo-xylanase activities. Exo-xylanases are active on natural xylan substances, hydrolyzing long-chain xylo-oligomers from the reducing end to produce short-chain xylo-oligomers and xylose. Exo-xylanases usually show multiple enzyme functions such as β-xylosidase, exo-glucanase, β-glucosidase, and arabinofuranosidase activities, which are helpful for more efficient hydrolysis of xylan. The combined use of exo- and endo-xylanases can increase the xylose yield compared to using either of them alone. Screening new exo-xylanase-producing microbes, mining the enzyme coding sequences, genetically engineering the enzymes, and producing them in a large scale are recommended for their commercial applications in lignocellulose-based biorefinery.
authors: Institute of Chemical and Engineering Sciences, Agency for Science, Technology and Research (A*STAR), 1 Pesek Road, Jurong Island, 627833, Singapore.
authors: Veeresh
authors: V
authors: Juturu
authors: Jin Chuan
authors: JC
authors: Wu
mesh_terms: D043364:Endo-1,4-beta Xylanases / Q000737:chemistry* / Q000378:metabolism; D005656:Fungal Proteins / Q000737:chemistry* / Q000378:metabolism; D006868:Hydrolysis; D008031:Lignin / Q000737:chemistry* / Q000378:metabolism; D017434:Protein Structure, Tertiary; D013379:Substrate Specificity; D014242:Trichoderma / Q000201:enzymology*; D014990:Xylans / Q000737:chemistry* / Q000378:metabolism; D014994:Xylose / Q000737:chemistry* / Q000378:metabolism
chemical_list: D005656:Fungal Proteins; D014990:Xylans; C036909:lignocellulose; D008031:Lignin; D014994:Xylose; D043364:Endo-1,4-beta Xylanases