title: A protease-insensitive feruloyl esterase from China Holstein cow rumen metagenomic library: expression, characterization, and utilization in ferulic acid release from wheat straw.
abstract: A metagenomic library of China Holstein cow rumen microbes was constructed and screened for novel gene cluster. A novel feruloyl esterase (FAE) gene was identified with a length of 789 bp and encoded a protein displaying 56% identity to known esterase sequences. The gene was functionally expressed in  Escherichia coli  BL21 (DE3), and the total molecular weight of the recombined protein was 32.4 kDa. The purified enzyme showed a broad specificity against the four methyl esters of hydroxycinnamic acids and high activity (259.5 U/mg) to methyl ferulate at optimum conditions (pH 8.0, 40 °C). High thermal and pH stability were also observed. Moreover, the enzyme showed broad resistance to proteases. FAE-SH1 can enhance the release of ferulic acid from wheat straw with cellulase, β-1,4-endoxylanase, β-1,3-glucanase, and pectase. These features suggest FAE-SH1 as a good candidate to enhance biomass degradation and improve the health effects of food and forage.
authors.affiliation: College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, China.
authors.forename: Fansheng
authors.initials: F
authors.lastname: Cheng
authors.forename: Jiping
authors.initials: J
authors.lastname: Sheng
authors.forename: Ting
authors.initials: T
authors.lastname: Cai
authors.forename: Jian
authors.initials: J
authors.lastname: Jin
authors.forename: Wanzhen
authors.initials: W
authors.lastname: Liu
authors.forename: Yanmei
authors.initials: Y
authors.lastname: Lin
authors.forename: Yongxin
authors.initials: Y
authors.lastname: Du
authors.forename: Maoqiu
authors.initials: M
authors.lastname: Zhang
authors.forename: Lin
authors.initials: L
authors.lastname: Shen
mesh_terms: D000818:Animals; D001419:Bacteria / Q000201:enzymology* / Q000235:genetics; D001426:Bacterial Proteins / Q000037:antagonists & inhibitors / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D002265:Carboxylic Ester Hydrolases / Q000037:antagonists & inhibitors / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D002417:Cattle; D002681:China; D003373:Coumaric Acids / Q000378:metabolism*; D004795:Enzyme Stability; D054892:Metagenome; D056186:Metagenomics; D010447:Peptide Hydrolases / Q000378:metabolism*; D012417:Rumen / Q000737:chemistry / Q000382:microbiology*; D013379:Substrate Specificity; D014908:Triticum / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D003373:Coumaric Acids; C004999:ferulic acid; D002265:Carboxylic Ester Hydrolases; C070196:feruloyl esterase; D010447:Peptide Hydrolases