集胞藻PCC 6803染色体上relNEs位点TA系统编码产物对蓝藻细胞生长的影响  

Effect of proteins encoded by chromosomal TA locus relNEs on growth of Syenchocystis PCC 6803

作　　者：周阳[1] 彭银仙[1] 刘朝莹[2] 赵卫飞[2] 

机构地区：[1]江苏科技大学生物与化学工程学院,镇江212013 [2]江苏大学环境与安全工程学院,镇江212013

出　　处：《应用与环境生物学报》2014年第5期934-937,共4页Chinese Journal of Applied and Environmental Biology

基　　金：国家自然科学基金项目(30 771176)资助~~

摘　　要：细菌毒素-抗毒素(Toxin-antitoxin,TA)系统最重要的特点是毒素蛋白具有生长抑制作用,抗毒素蛋白能拮抗这种生长抑制作用.为证明蓝藻细胞染色体上relNEs系统的生理功能,利用受Cu2+诱导的启动子PpetE控制集胞藻PCC6803染色体上公认的TA系统位点relNEs基因的表达调控突变株,分析编码产物对蓝藻细胞生长的影响.结果显示:Cu2+诱导毒素基因relEs过表达,藻细胞生长明显受到抑制,而Cu2+诱导毒素抗毒素基因relNEs共表达的菌株(DR381-486)则可以正常生长.研究结果表明诱导relEs表达产物能抑制自源宿主集胞藻细胞的生长,而RelN能拮抗RelEs的这种生长抑制作用,进一步证明集胞藻染色体上的操纵子构成rel家族TA系统.A crucial characteristics of bacterial toxin-antitoxin（TA） systems is the growth inhibition effect of the toxins, which can be neutralize by their cognate antitoxins. This study aimed to prove the physiological function of relNEs TA systerm on the chromosome of Synechocystis PCC6803. We constructed the regulation mutants where the Cu2＋-inducible promoter PpetE was used to control expression of the TA system relNEs on the chromosome of Synechocystis PCC6803. Growth of the mutants was analyzed in the absence or presence of copper ion. The results showed that under the background of deletion of relNEs system, the over expression of relEs induced with copper ion significantly inhibited algae cell growth, and that the coexpression of relNEs restored cell growth. These results showed that expression of the gene relEs causes growth arrest of cyanobacteria cells, and that RelN can counteract this inhibition effect of RelEs, further demonstrating that the operon relNEs forms a functional TA system of the rel TA family.

关 键 词：集胞藻PCC 6803 Cu^2+诱导启动子 TA系统 relNEs位点 

分 类 号：Q943.2[生物学—植物学]