Significantly improved solvent tolerance of Escherichia coli by global transcription machinery engineering. Issue 1 (December 2015)

• Record Type: Journal Article
• Authors: Zhang, Fa; Qian, Xiaohong; Si, Haiming; Xu, Guochao; Han, Ruizhi; Ni, Ye
• Is Part Of: Microbial cell factories. Volume 14:Issue 1(2015)
• Page Start: 1
• Page End: 11
• Publication Date: 2015-12
• Subjects: Global transcription machinery engineering -- Sigma factor 70 -- Organic solvent tolerance -- Escherichia coli -- gapA -- sdhB -- pepB; Microbial biotechnology -- Periodicals; Recombinant proteins -- Synthesis -- Periodicals; 660.62
• DOI: 10.1186/s12934-015-0368-4
• Languages: English
• ISSNs: 1475-2859

Abstract

Abstract Background Escherichia coli has emerged as a promising platform microorganism to produce biofuels and fine chemicals of industrial interests. Certain obstacles however remain to be overcome, among which organic-solvent tolerance is a crucial one. Results We used global transcription machinery engineering (gTME) to improve the organic-solvent tolerance (OST) ofE. coli JM109. A mutant library of σ70 encoded byrpoD was screened under cyclohexane pressure.E. coli JM109 strain harboring σ70 mutant C9 was identified with capability of tolerating 69 % cyclohexane. TherpoD mutant contains three amino-acid substitutes and a stop-codon mutation, resulting a truncated sequence containing regions σ1.1 and σ1.2 . Total protein difference produced byE. coli JM109 strain harboring C9 was examined with 2D-PAGE, and 204 high-abundant proteins showed over twofold variation under different solvent stress. Conclusions Our results show that several genes (gapA, sdhB, pepB anddppA ) play critical roles in enhanced solvent tolerance ofE. coli, mainly involving in maintaining higher intracellular energy level under solvent stress. Global transcription machinery engineering is therefore a feasible and efficient approach for engineering strain with enhanced OST-phenotype.