潘柯莉¹,茅以诚²,岳圣杰¹,姚瑞莲¹,胡洪波¹

• 1:微生物代谢国家重点实验室，上海交通大学 生命科学技术学院，上海 200240
• 2:复旦大学 药学院，上海 201203

摘要(Abstract)：

木质纤维素是地球上最丰富的碳源，可广泛应用于生物燃料和生物化工。但是由于分解代谢阻遏，不能完全利用木质纤维素降解产物中获得的多种糖类，严重制约了木质纤维素的商业应用。研究主要构建了一株可以同时消耗葡萄糖、果糖、木糖的菌株E.coli BW25113 △pgi，并探讨了其分别在好氧和厌氧条件下以葡萄糖、果糖、木糖为混合碳源时的碳源利用情况。敲除pgi后，葡萄糖、果糖、木糖三种糖被同时消耗。研究通过发酵数据、基因转录水平数据和代谢流分析数据阐述了敲除pgi解除分解代谢阻遏的机理。pgi基因的敲除导致ptsG转录水平下降，增加了cAMP-Crp的含量，从而解除分解代谢阻遏，实现了混合碳源的共利用，为木质纤维素的开发利用提供了新的思路。

关键词(KeyWords)： 大肠杆菌;pgi敲除;碳源共利用;代谢调控

Abstract:

Keywords:

基金项目(Foundation): 国家自然科学青年基金（31400086，81402956）；中国博士后科学基金（2016M601584）；上海市科委晨光计划（14CG03）。

作者(Author): 潘柯莉¹,茅以诚²,岳圣杰¹,姚瑞莲¹,胡洪波¹

DOI: 10.3969/j.issn.1003-9015.2018.01.019

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