沙福芽孢杆菌氧化磷酸化通路相关基因对锰胁迫的应答  

Response of genes related to oxidative phosphorylation pathway of Bacillus safensis under manganese stress

作　　者：龙红 牛熙[1] 黄世会 冉雪琴[1] 王嘉福[1] LONG Hong;NIU Xi;HUANG Shihui;RAN Xueqin;WANG Jiafu(Institute of Agricultural Bioengineering/Institute of Animal Science,Guizhou University,Guizhou,Guiyang 550025,China)

机构地区：[1]贵州大学农业生物工程研究院/贵州大学动物科学学院,贵州贵阳550025

出　　处：《工业微生物》2020年第4期27-33,共7页Industrial Microbiology

基　　金：贵州省科技创新人才团队项目(编号:[2019]5615);贵州省“百”层次创新型人才培养项目(编号:[2016]4012)。

摘　　要：氧化磷酸化是细菌生成ATP的重要途径之一,同时有研究表明能量供应不足是发生锰毒害的重要机制。为了解析锰胁迫条件下,耐锰细菌是如何通过能量代谢的改变以应对锰毒害。以耐锰菌沙福芽孢杆菌S7为研究材料,挑选细菌电子传递链细胞色素亚基编码基因qcrB、ctaD,以及ATP合成酶亚基编码基因atpA、atpD和atpG,采用荧光定量PCR方法,设置250 mg/L和2200mg/L两个锰处理浓度,比较基因表达的时序性变化。与无锰对照组的表达量相比,3个ATP合成酶亚基编码基因的表达量较为接近,中等浓度锰胁迫条件下,3个基因的表达量明显低于2200mg/L锰处理的表达量;锰作用初期各基因的表达量较低,4 h后表达量上升,8 h和/或32 h时表达量达到峰值,基因的表达量的时间变化呈现出单峰或双峰变化趋势。两个电子传递链上细胞色素亚基编码基因qcrB和ctaD的表达量略高于ATP合成酶3个亚基基因的相应值,表达规律与ATP合成酶一样。研究结果提示,耐锰菌沙福芽孢杆菌S7的能量代谢水平随着作用时间和浓度的提高而上升,产生大量的ATP以应对锰毒害作用。Oxidative phosphorylation is one of the important ways for bacteria to produce ATP as energy supply;meanwhile some previous studies reported that insufficient energy supply was an important mechanism of manganese toxicity.In order to understand how manganese-tolerant bacteria deal with manganese toxicity through the regulation of energy metabolism under manganese stress,manganese-resistant bacterium Bacillus safensis S7 was used as samples,two genes of qcr B and ctaD,encoding the cytochrome subunits of the electron transport chain and the genes of atpA,atpD and atpG,encoding the subunits of ATP synthase were selected.Two manganese treatment concentrations of 250 mg/L and2200 mg/L were set,and the sequential changes of gene expression were compared by fluorescence quantitative PCR method.Compared with the control group without manganese supply,the expression of three ATP synthase subunits was similar.Under medium manganese stress,the expression of three genes was significantly lower than that of 2200 mg/L manganese treatment.The expression of each ATP synthase subunit gene was low at the initial stage of manganese treatment,and increased after 4 h and then reached the peak at 8 h and/or 32 h.The time change of gene expression revealed a trend of single peak or double peak.The expression of cytochrome subunit coding genes qcr B and ctaD on the two electron transport chains was slightly higher than that of the three subunits of ATP synthase,and the expression pattern was the same as that of ATP synthase.The results showed that the energy metabolism level in Bacillus safensis S7 increased with the increase of treatment time and concentration,so as to produce enough ATP to deal with the toxic effect of manganese.

关 键 词：沙福芽孢杆菌 锰胁迫 基因表达 氧化磷酸化 ATP合成酶 

分 类 号：Q935[生物学—微生物学]