The change of the state of cell membrane can enhance the synthesis of menaquinone in Escherichia coli
详细信息 查看全文
- 作者：Yan Liu ; Xiu-min Ding ; Zheng-lian Xue…
- 关键词：Menaquinone ; Cell membranes ; Membrane fluidity ; Leakage
- 刊名：World Journal of Microbiology and Biotechnology
- 出版年：2017
- 出版时间：March 2017
- 年：2017
- 卷：33
- 期：3
- 全文大小：
- 刊物类别：Chemistry and Materials Science
- 刊物主题：Applied Microbiology; Biotechnology; Biochemistry, general; Environmental Engineering/Biotechnology; Microbiology;
- 出版者：Springer Netherlands
- ISSN：1573-0972
- 卷排序：33
文摘
Menaquinone (MK) was an attractive membrane-bound intracellular chemical. To enhance its production, we tried to find the relationship between its synthesis and the state of cell membrane in producing strain. Due to non-ionic surfactant-polyoxyethylene oleyl ether (POE) and plant oil-cedar wood oil (CWO) can typically increase extracellular secretion and intracellular synthesis of MK respectively, the effect of these two substances on cell morphology, physical properties of cell membrane was investigated. Finally, two engineering strains were constructed to verify whether the state of cell membrane can enhance MK synthesis. The result showed that the edge of cells was broken when POE added in the medium. Other physical properties such as total fatty acid content decreased by 40.7% and the ratio of saturated fatty acids to unsaturated fatty acids decreased from 1.58 ± 0.05 to 1.31 ± 0.04. Meanwhile, cell membrane leakage was enhanced from 7.14 to 64.31%. Different from POE group, cell membrane was intact in CWO group. Moreover, the ratio of saturated fatty acids to unsaturated fatty acids increased from 1.58 ± 0.05 to 1.78 ± 0.04 and the average lipid length decreased from 16.05 ± 0.08 to 15.99 ± 0.10. Two constructed strains, especially Escherichia coli DH5α FatB, exhibited strong MK secretion ability and the extracellular MK reached 10.71 ± 0.19 mg/L. An understanding of these functionary mechanisms could not only provide a new idea for the synthesis of MK, but also provide a reference to increase the yield of intracellular membrane-bound metabolites.