title: Biochemical and Thermodynamic Characterization of a Novel, Low Molecular Weight Xylanase from Bacillus Methylotrophicus CSB40 Isolated from Traditional Korean Food.
abstract: A low molecular weight xylanase from Bacillus strain CSB40, isolated from traditional Korean food and produced in beechwood xylan, was biochemically and thermodynamically characterized. It was purified 8.12-fold with a 15.88 % yield using DEAE sepharose fast flow, and it was determined to have a mass of ∼27 kDa via sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and xylan zymography. The purified xylanase was optimally active at 50 °C and pH 6 and stable over a wide range of pH (4.5-12.5). The N-terminal amino acid sequence of xylanase was GIQQGDDGKL. The activation energy for beechwood xylan hydrolysis was 29.39 kJmol(-1) with k cat value of 927.582 × 10(2) s(-1). K m and V max were 0.080 mg/ml and 794.63 mmol min(-1) mg(-1). The analysis of other thermodynamic parameters like ∆H, ∆G, ∆S, Q10, ∆GE-S, and ∆GE-T also supported the spontaneous formation of products, greater hydrolytic efficiency, and feasibility of enzymatic reaction, which also ratifies the novelty of this xylanase. The enzyme was strongly activated by Zn(2+) and inhibited by Cu(2+). The principal hydrolyzed end-products of this xylanase are xylobiose, xylotriose, and xylotetrose, which can be used in the pharmaceutical industry and as prebiotic in food.
authors.affiliation: Department of Pharmacy, Chosun University, Gwangju, Korea.
authors.forename: Sandesh
authors.initials: S
authors.lastname: Panthi
authors.affiliation: Department of Pharmacy, Chosun University, Gwangju, Korea.
authors.forename: Yoon Seok
authors.initials: YS
authors.lastname: Choi
authors.affiliation: Department of Pharmacy, Chosun University, Gwangju, Korea.
authors.forename: Yun Hee
authors.initials: YH
authors.lastname: Choi
authors.affiliation: Department of Pharmacy, Chosun University, Gwangju, Korea.
authors.forename: MiRi
authors.initials: M
authors.lastname: Kim
authors.affiliation: Department of Pharmacy, Chosun University, Gwangju, Korea. jcyu@chosun.ac.kr.
authors.forename: Jin Cheol
authors.initials: JC
authors.lastname: Yoo
mesh_terms: D000595:Amino Acid Sequence; D001407:Bacillus / Q000201:enzymology*; D003300:Copper / Q000737:chemistry; D043364:Endo-1,4-beta Xylanases / Q000037:antagonists & inhibitors / Q000096:biosynthesis* / Q000737:chemistry / Q000302:isolation & purification*; D004795:Enzyme Stability; D008970:Molecular Weight; D013816:Thermodynamics; D014990:Xylans / Q000737:chemistry*; D015032:Zinc / Q000737:chemistry
chemical_list: D014990:Xylans; D003300:Copper; D043364:Endo-1,4-beta Xylanases; D015032:Zinc
keywords: Bacillus methylotrophicus; Low molecular weight xylanase; Thermodynamic characterization; Xylooligosaccharides