细菌的有机溶剂耐受机制

Tolerant mechanisms of bacteria to organic solvents

摘要:

有机溶剂有严重破坏微生物正常生理功能的毒害作用, 但是研究工作者发现有些细菌能够在较高有机溶剂浓度下依赖独特的耐受机制得以生存, 这种机制的发现大大鼓舞了工业菌尤其是溶剂生产菌和毒性有机物降解菌的工业适应性改造研究。以下概述了有机溶剂对细胞毒性作用机制, 并在根据参数logP衡量不同溶剂对细胞的毒性程度的基础上, 重点总结了溶剂耐受菌耐受有机溶剂的机制, 即膜上顺反异构、增加饱和脂肪酸的比率、改变极性头部、外膜的生理变化、细胞的形态变化、胞内溶剂的降解和泵出等, 结合本课题组在筛选溶剂耐受菌株和提高现有菌株溶剂耐受性研究方面的经验, 希望对重要工业微生物溶剂耐受相关的生理功能进行更深入地研究, 提高微生物的工业适应性。

Abstract:

Organic solvents are usually toxic to microorganisms for destroying the physiological functions. Recently, some studies have revealed that some bacteria are capable of living in conditions with high concentration of solvents through tolerant and adaptive mechanisms. This discovery inspires the research on adaptation and alteration of industrial bacteria, especially for those producing solvents or degrading toxic organic compounds. For a deep understanding and a wide application of the tolerant mechanisms, we address here the recent discoveries on solvents toxicity to bacteria by the parameter logP, and tolerant mechanisms of solvent-tolerant-bacteria to solvents, such as changes in cell membrane including cis-trans isomerisation, the saturated-to-unsaturated fatty acids ratio and the phospholipids head-groups, changes in outer membrane and cell morphology, and other stress responses. Moreover, our experiences in screening novel solvent-tolerant-bacteria and methods in increasing solvent tolerance of industrial microbes are introduced to give a promising strategy for improving solvent production.