生物技术通报 ›› 2020, Vol. 36 ›› Issue (7): 112-118.doi: 10.13560/j.cnki.biotech.bull.1985.2020-0004

• 研究报告 • 上一篇    下一篇

聚羟基丁酸酯合成引发的高密度生长大肠杆菌的多位点突变分析

陈桥1,2, 吴海英1,3, 王宗寿4, 谢雨康1,2, 李宜青1,3, 孙俊松1,2,3   

  1. 1.中国科学院上海高等研究院,上海 201210;
    2.中国科学院大学,北京 100049;
    3.上海科技大学,上海 201210;
    4.福建省南平市畜牧站,南平 353000
  • 收稿日期:2020-01-03 出版日期:2020-07-26 发布日期:2020-07-28
  • 作者简介:陈桥,男,硕士研究生,研究方向:微生物代谢工程;E-mail:chenqiao@sari.ac.cn
  • 基金资助:
    福建省STS合作项目(2018T3021)

Multiple-site Mutations in Escherichia coli Capable of High-density Growing Induced from the Biosynthesis of Polyhydroxybutyrate

CHEN Qiao1,2, WU Hai-ying1,3, WANG Zong-shou4, XIE Yu-kang1,2, LI Yi-qing1,3, SUN Jun-song1,2,3   

  1. 1. Shanghai Advanced Research Institute,Chinese Academy of Sciences,Shanghai 201210;
    2. University of Chinese Academy of Sciences,Beijing 100049;
    3. Shanghai Tech University,Shanghai 201210;
    4. Animal Husbandry Station of Nanping City,Nanping 353000
  • Received:2020-01-03 Published:2020-07-26 Online:2020-07-28

摘要: 聚-3-羟基丁酸酯(PHB)的合成可以通过在重组大肠杆菌中过表达phaCAB操纵子实现。提升菌株的性能被认为是降低PHB生产成本的关键因素之一。在大肠杆菌S17-3中表达PHB的合成质粒pBhya-CAB,却可以自发实现菌株的高密度生长,摇瓶生长时的最高OD600可达40左右。全基因组扫描测序和转录组测序分析比对表明,一些编码碳代谢流相关蛋白如磷酸葡萄糖异构酶(pgi)和6-磷酸葡萄糖脱氢酶(zwf)发生了阅读框序列或转录水平的改变。在S17-3中敲除zwf会导致转化菌株生长密度的降低,而在模式大肠杆菌BW25113中敲除pgi则会引起转化子的生长密度变高,揭示了S17-3高密度生长与自身碳代谢流的优化密切相关。

关键词: 大肠杆菌, 聚-3-羟基丁酸酯, 高密度生长, 磷酸葡萄糖异构酶, 6-磷酸葡萄糖脱氢酶

Abstract: Biosynthesis of polyhydroxybutyrate(PHB)in Escherichia coli can be achieved by the overexpression of the operon phaCAB. Improving strain performance is regarded as the one of the key factors to lower the cost of PHB bio-production. An E. coli mutant S17-3,when having synthetized plasmid pBhya-CAB of expressing PHB,is able to grow at high density,and the maximal OD600 reached about 40 when growing in shake flasks. Comparative analysis of whole-genome scan sequencing and transcriptome sequencing revealed that mutations in reading frame sequence or at transcription level occurred in the carbon metabolic flux-related proteins,such as pgi of encoding phosphoglucose isomerase and zwf of encoding glucose-6-phosphate 1-dehydrogenase. Null deletion of zwf in S17-3 diminished the growth density of the strain,while pgi knockout in BW25113 promoted the transformant cells’ growth density. Therefore,it is revealed that the high-density growth of S17-3 is closely related to the optimization of itself carbon metabolic flux.

Key words: Escherichia coli, polyhydroxybutyrate, high-density growth, phosphoglucose isomerase, glucose-6-phosphate 1-dehydrogenase