木糖产乙醇微生物的育种研究进展

Research Progress on Breeding of Microorganisms for Producing Ethanol from Xylose

甘蔗渣水解产物中含量第二高的是木糖,利用微生物高效转化木糖产乙醇是目前蔗渣纤维综合利用的关键途径之一,但野生型酿酒酵母(Saccharomyces cerevisiae)不能利用木糖发酵产乙醇,这成为当前纤维素乙醇实现产业化生产的主要瓶颈之一。本文从微生物木糖代谢途径、利用木糖产乙醇的微生物、木糖产乙醇基因工程菌的构建、利用传统诱变方法改良木糖乙醇菌种等4个方面综述当前木糖产乙醇微生物的育种研究进展,指出木糖乙醇发酵最为理想的微生物菌种和最有应用前景的微生物分别是树干毕赤酵母(Pichia stipitis)和酿酒酵母基因工程菌,为改良木糖乙醇微生物提供理论依据。

The second highest content in sugarcane bagasse hydrolysis products is xylose.The efficient conversion of xylose to ethanol by microorganisms is currently one of the key pathways in the comprehensive utilization of bagasse fibers.However,wild-type Saccharomyces cerevisiae could not produce ethanol by xylose fermentation,which has become one of the main bottlenecks in the industrialization of cellulosic ethanol.In this article,the research progress on the breeding of xylose ethanol producing microorganisms was reviewed from four aspects:microbial xylose metabolic pathway,microorganisms using xylose to produce ethanol,construction of xylose ethanol-producing genetic engineering bacteria,and improvement of xylose ethanol-producing strains by traditional mutation methods.One of the most ideal microbial strains and the most promising microorganisms for xylose ethanol fermentation are Pichia stipitis and S.cerevisiae genetically engineering bacteria were pointed out,respectively,which provides a theoretical basis for improving xylose ethanol microorganisms.