工业微生物2016，Vol.46Issue(4)：1-7,7.DOI:10.3969/j.issn.1001-6678.2016.04.001
双组份转运系统BrnFE的过表达和表面活性剂的添加对谷氨酸棒杆菌发酵生产L-异亮氨酸的影响
Effects of overexpressing two-component export system BrnFE and adding surfactants on L-isoleucine production by Corynebacterium glutamicum
摘要
Abstract
In order to increase L-isoleucine productivity in Corynebacterium glutamicum LD320 , the L-isoleucine secretion system was improved. Both the mutated brnFE operon and the wild type brnFE operon were cloned into the shutter expression vector pXMJ19 individually, and the resultant plasmids pXMJ19-brnFE and pXMJ19-brnFE1 were transformed into LD320. Then the L-isoleucine production by these two strains was compared and analyzed. More L-isoleucine was produced by LD320/pXMJ19-brnFE than that by LD320/pXMJ19-brnFE1. In addition, the effects of several surfactants on growth and L-isoleucine production by LD320/pXMJ19-brnFE1 were investigated. The shaking flask results revealed that Tween-80 played a key role in cell growth and L-isoleucine production. The suitable concentration of Tween-80 was 0. 5 g/L and the optimal adding time was 16 h. Furthermore, the effects of Tween-80 on cell growth and L-isoleucine production by LD320/pXMJ19-brnFE1 was also investigated in a 7 L fermentor. The concentration of L-isoleucine increased from 18. 53 g/L to 25. 45 g/L, which was 37% higher than that of the control strain.关键词
双组份转运系统BrnFE/表面活性剂/谷氨酸棒杆菌/L-异亮氨酸Key words
BrnFE/surfactants/Corynebacterium glutamicum/L-isoleucine引用本文复制引用
李忠财,董会娜,丛丽娜,张大伟..双组份转运系统BrnFE的过表达和表面活性剂的添加对谷氨酸棒杆菌发酵生产L-异亮氨酸的影响[J].工业微生物,2016,46(4):1-7,7.基金项目
国家自然基金(31370089),天津市科技支撑计划重点项目(14ZCZDSY00065),天津市自然科学基金(16JCYBJC23500,15JCQNJC09500)。 （31370089）
