title: Gene cloning, sequencing, and biochemical characterization of endoxylanase from Thermoanaerobacterium saccharolyticum B6A-RI.
abstract: The gene encoding endoxylanase (xynA) from Thermoanaerobacterium saccharolyticum B6A-RI was cloned and expressed in Escherichia coli. A putative 33-amino-acid signal peptide, which corresponded to the N-terminal amino acids, was encoded by xynA. An open reading frame of 3,471 bp, corresponding to 1,157 amino acid residues, was found, giving the xynA gene product a molecular mass of 130 kDa. xynA from T. saccharolyticum B6A-RI had strong similarity to genes from family F beta-glycanases. The temperature and pH optimum for the activity of the cloned endoxylanase were 70 degrees C and 5.5, respectively. The cloned endoxylanase A was stable at 75 degrees C for 60 min and displayed a specific activity of 227.4 U/mg of protein on oat spelt xylan. The cloned xylanase was an endo-acting enzyme.
authors.affiliation: Department of Microbiology and Public Health, Michigan State University, East Lansing 48824.
authors.forename: Y E
authors.initials: YE
authors.lastname: Lee
authors.forename: S E
authors.initials: SE
authors.lastname: Lowe
authors.forename: J G
authors.initials: JG
authors.lastname: Zeikus
mesh_terms: D001421:Bacteria, Anaerobic / Q000201:enzymology* / Q000235:genetics*; D002874:Chromosome Mapping; D003001:Cloning, Molecular; D004269:DNA, Bacterial / Q000235:genetics; D043364:Endo-1,4-beta Xylanases; D004926:Escherichia coli / Q000235:genetics; D005798:Genes, Bacterial; D006026:Glycoside Hydrolases / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D006868:Hydrolysis; D007700:Kinetics; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D021382:Protein Sorting Signals / Q000235:genetics; D014990:Xylans
chemical_list: D004269:DNA, Bacterial; D021382:Protein Sorting Signals; D014990:Xylans; D006026:Glycoside Hydrolases; D043364:Endo-1,4-beta Xylanases