초록
<P>Enzymatic hydrolysis is one of the most important processes in bioethanol production from lignocellulosic biomass. <I>Acremonium cellulolyticus </I>is a filamentous fungus with high cellulase production but productivity of hemicellulase, especially β-xylosidase, is lower than other filamentous fungi. We identified 2.4 Kb β-xylosidase gene in the <I>A. cellulolyticus </I>genome sequence information and it encoded 798 amino acids without introns. To enhance hemicellulase productivity in <I>A. cellulolyticus</I>, we transformed this fungus with the identified β-xylosidase gene driven by the <I>cellobiohydrolase Ι </I>(<I>cbh1</I>) promoter, using the protoplast-polyethyleneglycol (PEG) method, and obtained a transformant, YKX1. Hydrolysis rate of xylooligosaccharides was more than 50-fold higher using culture supernatant from YKX1 than that from the parental strain, Y-94. Total cellulase activity (measured by filter paper assay) in YKX1 was not affected by the <I>cbh1 </I>promoter used for expression of β-xylosidase, and induced by cellulose. Since YKX1 can produce larger amount of β-xylosidase without affecting cellulase productivity, it is considered to be beneficial for practical monosaccharide recoveries from lignocellulosic biomass.</P>