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Published on: October 24, 2016
Characterization of an ethanol-tolerant 1,4-β-xylosidase produced by Pichia membranifaciens
A M Romero1, J J Mateo1, S Maicas1
1Departament de Microbiologia i Ecologia, Universitat de València, Burjassot, Spain.
Aims:
The purification and biochemical properties of the 1,4-β-xylosidase of an oenological yeast were investigated.
Methods And Results:
An ethanol-tolerant 1,4-β-xylosidase was purified from cultures of a strain of Pichia membranifaciens grown on xylan at 28°C. The enzyme was purified by sequential chromatography on DEAE cellulose and Sephadex G-100. The relative molecular mass of the enzyme was determined to be 50kDa by SDS-PAGE. The activity of 1,4-β-xylosidase was optimum at pH 6·0 and at 35°C. The activity had a Km of 0·48±0·06mmol l(-1) and a Vmax of 7·4±0·1μmol min(-1)mg(-1) protein for p-nitrophenyl-β-d-xylopyranoside.
Conclusions:
The enzyme characteristics (pH and thermal stability, low inhibition rate by glucose and ethanol tolerance) make this enzyme a good candidate to be used in enzymatic production of xylose and improvement of hemicellulose saccharification for production of bioethanol.
Significance And Impact Of The Study:
This study may be useful for assessing the ability of the 1,4-β-xylosidase from P. membranifaciens to be used in the bioethanol production process.
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