초록
<P>The endo-β-1,4-glucanase gene <I>celE</I> from the anaerobic fungus <I>Orpinomyces</I> PC-2 was placed under the control of an alcohol oxidase promoter (AOX1) in the plasmid pPIC9K, and integrated into the genome of a methylotrophic yeast <I>P. pastoris</I> GS115 by electroporation. The strain with highest endo-β-1,4-glucanase activity was selected and designed as <I>P. pastoris</I> egE, and cultivated in shaking flasks. The culture supernatant was assayed by SDS-polyacrylamide gel electrophoresis and showed a single band at about 52 kDa. Furthermore, the recombinant <I>P. pastoris</I> egE was proved to possess the ability to utilize sodium carboxymethyl cellulose as a carbon source. The recombinant endoglucanase produced by <I>P. pastoris</I> showed maximum activity at pH 6.0 and temperature 45 °C, indicating it was a mesophilic neutral endo-β-1,4-glucanase, suitable for denim biofinishing/washing. Further research was carried out in suitable fermentation medium in shaking flasks. The most favorable methanol addition concentration was discussed and given as 1.0%. After methanol induction for 96 h, the endo-β-1,4-glucanase activity reached 72.5 IU mL<SUP>−1</SUP>. This is the first report on expression and characterization of endo-β-1,4-glucanase from <I>Orpinomyces</I> in <I>P. pastoris</I>. The endo-β-1,4-glucanase secreted by recombinant <I>P. pastoris</I> represents an attractive potential for both academic research and textile industry application.</P>