绿针假单胞菌HT66中luxR_19对吩嗪-1-甲酰胺合成的影响  

The Effects of lux R_19 on the Synthesis of Phenzaine-1-carboxamide in Pseudomonas chlororaphis HT66

作　　者：陈亚汶 彭华松[1] 王威[1] 张雪洪[1] 

机构地区：[1]上海交通大学生命科学技术学院微生物代谢国家重点实验室,上海200240

出　　处：《生物技术通报》2015年第8期166-173,共8页Biotechnology Bulletin

基　　金：国家自然科学基金项目(31270084);国家"863"计划项目(2012AA022107)

摘　　要：旨在研究调控基因lux R_19对绿针假单胞菌HT66中的抑菌物质吩嗪-1-甲酰胺(phenazine-1-carboxamide,PCN)合成及菌体生长的影响,通过分子操作构建了lux R_19基因敲除株、回补菌株、过表达菌株以及lux R_19(G85A)点突变菌株,检测了目标菌株生长曲线、PCN发酵结果、细菌泳动性与从动性等。结果显示,将lux R_19敲除后PCN产量明显降低,对lux R_19基因进行过表达,发现能够将PCN产量提高2倍;lux R_19对于吩嗪合成的多个调控基因以及合成基因表达均产生影响;lux R_19的敲除对HT66的生长及泳动性不产生影响,而对细菌的从动性有一定的促进作用;lux R_19(G85A)点突变菌株吩嗪产量较野生型相差很小。结果表明,lux R_19对PCN的合成为正调控基因,一定程度上影响HT66的从动性,第254位碱基突变对PCN合成产量不产生影响。In order to study the potential effects of regulator gene luxR_19 on the synthesis of antibacterial substance phenazine-1- carboxamide （ PCN ） and physiological-biochemical characteristics in Pseudomonas chlororaphis HT66, strains of gene luxR_lg-knockout, -compIementatlon, -overexpression and -point-mutation were constructed, and then the growth curve, fermentation production of PCN, swimming and swarming activities were tested at the target strains. The results showed that the knockout of luxR_19 lowered the production of PCN and the over-expression of gene luxR_19 increased the double production of PCN compared to the wild type ; luxR_19 gene affected the expression of several genes relating to the regulation or synthesis of phenazines. Besides, the knockout of luxR_19 had no effects on the growth and swimming activity, however, promoted the swarming activity of HT66. The production of PCN in point-mutation strain of luxR_19 （ Gg5A ） was similar to that in wild type. The above results indicated that luxR_19 was the positive regulator of PCN production, and could affect the swarming activity of HT66. Besides, the point-mutation at 254th site in luxR19 did not affect the production of PCN.

关 键 词：绿针假单胞菌 HT66 吩嗪-1-甲酰胺 LUX R家族转录调控因子 

分 类 号：Q93[生物学—微生物学]