The recombinant endoglucanase gene (EG I) from Trichoderma reesei was successfully expressed in Pichia pastoris for the purpose of producing oligosaccharides from various biomass-derived substrates. Interestingly, the recombinant endoglucanase I (ReEG I) showed the catalytic activity towards both cellulose and xylan hydrolysis, yet it was more efficient with xylans. Among various glucans and xylans substrates (paper pulp, carboxymethylated cellulose, oat spelt xylan, birchwood xylan), birchwood xylan displayed a higher yield of xylooligosaccharides (XOS) (69.5 % after optimization). Eventually, it was observed that ReEG I could simultaneously produce XOS and COS, when the alkali-extracted corncob residues were used as substrate. This is the first report on simultaneous production of XOS and COS by recombinant endoglucanase I from Trichoderma reesei expressed in Pichia pastoris, where a novel application of genetically engineered enzymes is proposed to provide an attractive application for high value utilization of biomass.

中文翻译：

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利用里氏木霉重组内切葡聚糖酶同时生产生物质衍生寡糖的新方法

来自里氏木霉的重组内切葡聚糖酶基因 (EG I) 在毕赤酵母中成功表达，目的是从各种生物质衍生底物生产寡糖。有趣的是，重组内切葡聚糖酶 I (ReEG I) 显示出对纤维素和木聚糖水解的催化活性，但它对木聚糖更有效。在各种葡聚糖和木聚糖底物（纸浆、羧甲基化纤维素、燕麦拼写木聚糖、桦木木聚糖）中，桦木木聚糖的低聚木糖 (XOS) 产量更高（优化后为 69.5%）。最终，当碱提取的玉米芯残留物用作底物时，观察到 ReEG I 可以同时产生 XOS 和 COS。