title: Novel xylanase from a holstein cattle rumen metagenomic library and its application in xylooligosaccharide and ferulic Acid production from wheat straw.
abstract: A novel gene fragment containing a xylanase was identified from a Holstein cattle rumen metagenomic library. The novel xylanase (Xyln-SH1) belonged to the glycoside hydrolase family 10 (GH10) and exhibited a maximum of 44% identity to the glycoside hydrolase from  Clostridium thermocellum  ATCC 27405. Xyln-SH1 was heterologously expressed, purified, and characterized. A high level of activity was obtained under the optimum conditions of pH 6.5 and 40 °C. A substrate utilization study indicated that Xyln-SH1 was cellulase-free and strictly specific to xylan from softwood. The synergistic effects of Xyln-SH1 and feruloyl esterase (FAE-SH1) were observed for the release of xylooligosaccharides (XOS) and ferulic acid (FA) from wheat straw. In addition, a high dose of Xyln-SH1 alone was observed to improve the release of FA from wheat straw. These features suggest that this enzyme has substantial potential to improve biomass degradation and industrial applications.
authors.affiliation: College of Food Science and Nutritional Engineering, China Agricultural University , Beijing 100083, China.
authors.forename: Fansheng
authors.initials: F
authors.lastname: Cheng
authors.forename: Jiping
authors.initials: J
authors.lastname: Sheng
authors.forename: Rubo
authors.initials: R
authors.lastname: Dong
authors.forename: Yejun
authors.initials: Y
authors.lastname: Men
authors.forename: Lin
authors.initials: L
authors.lastname: Gan
authors.forename: Lin
authors.initials: L
authors.lastname: Shen
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002265:Carboxylic Ester Hydrolases; D002417:Cattle; D003001:Cloning, Molecular; D048013:Acetivibrio thermocellus / Q000201:enzymology; D003373:Coumaric Acids / Q000378:metabolism*; D043364:Endo-1,4-beta Xylanases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D015870:Gene Expression; D015723:Gene Library; D005965:Glucuronates / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D056186:Metagenomics; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009844:Oligosaccharides / Q000378:metabolism*; D012417:Rumen / Q000201:enzymology*; D017385:Sequence Homology; D013045:Species Specificity; D014908:Triticum / Q000737:chemistry
chemical_list: D003373:Coumaric Acids; D005965:Glucuronates; D009844:Oligosaccharides; C570991:xylooligosaccharide; C004999:ferulic acid; D002265:Carboxylic Ester Hydrolases; C070196:feruloyl esterase; D043364:Endo-1,4-beta Xylanases