The metabolic impact of extracellular nitrite on aerobic metabolism of Paracoccus denitrificans.
The metabolic impact of extracellular nitrite on aerobic metabolism of Paracoccus denitrificans.
复制标题
DOI：
10.1016/j.watres.2017.02.011
复制
发表时间：
2017-04-15
期刊：
影响因子：
12.8
通讯作者：
Richardson DJ
中科院分区：
文献类型：
--
作者：
Hartop KR;Sullivan MJ;Giannopoulos G;Gates AJ;Bond PL;Yuan Z;Clarke TA;Rowley G;Richardson DJ
亚硝酸盐与游离亚硝酸盐（FNA）平衡时，可以通过杀菌活性抑制微生物群落的好氧和厌氧生长，在一系列水系统中具有相当大的控制微生物生长的潜力。亚硝酸盐/FNA对厌氧代谢的影响一直备受关注，因此，为了进一步了解亚硝酸盐/FNA对有氧代谢的代谢影响，我们以反硝化副球菌PD1222为模型进行了研究。细胞外亚硝酸盐以ph依赖的方式抑制反硝化假单胞菌的好氧生长，这可能是由亚硝酸盐和游离亚硝酸盐（pKa = 3.25）以及随后由FNA进入反硝化假单胞菌细胞内传代产生的活性氮氧化物共同作用的结果。编码黄血红蛋白（Fhp）的基因（Pden_1689）在细胞外亚硝酸盐的作用下表达增加。缺失突变体的构建和分析表明，Fhp参与在高细胞外亚硝酸盐浓度下赋予亚硝酸盐/FNA抗性。全球转录分析证实了fhp的亚硝酸盐依赖性表达，并表明反硝化假单胞菌表达了许多与蛋白质、DNA和脂质修复相关的应激反应系统。因此，这表明亚硝酸盐引起ph依赖的应激反应，这是由于产生相关的活性氮物种，如FNA内化产生的一氧化氮。研究了反硝化副球菌，以评估亚硝酸盐对有氧代谢的影响。细胞外亚硝酸盐以ph依赖的方式抑制P.反硝化菌的有氧生长。在细胞外亚硝酸盐的作用下，观察到黄血红蛋白的表达增加。对一个突变体的分析证实黄血红蛋白与亚硝酸盐耐受性有关。只有约1.5%的基因组在亚硝酸盐“应激”下受到差异调节。
Nitrite, in equilibrium with free nitrous acid (FNA), can inhibit both aerobic and anaerobic growth of microbial communities through bactericidal activities that have considerable potential for control of microbial growth in a range of water systems. There has been much focus on the effect of nitrite/FNA on anaerobic metabolism and so, to enhance understanding of the metabolic impact of nitrite/FNA on aerobic metabolism, a study was undertaken with a model denitrifying bacterium Paracoccus denitrificans PD1222. Extracellular nitrite inhibits aerobic growth of P. denitrificans in a pH-dependent manner that is likely to be a result of both nitrite and free nitrous acid (pKa = 3.25) and subsequent reactive nitrogen oxides generated from the intracellular passage of FNA into P. denitrificans. Increased expression of a gene encoding a flavohemoglobin protein (Fhp) (Pden_1689) was observed in response to extracellular nitrite. Construction and analysis of a deletion mutant established Fhp to be involved in endowing nitrite/FNA resistance at high extracellular nitrite concentrations. Global transcriptional analysis confirmed nitrite-dependent expression of fhp and indicated that P. denitrificans expressed a number of stress response systems associated with protein, DNA and lipid repair. It is therefore suggested that nitrite causes a pH-dependent stress response that is due to the production of associated reactive nitrogen species, such as nitric oxide from the internalisation of FNA. Paracoccus denitrificans was studied to assess the impact of nitrite on aerobic metabolism. Extracellular nitrite inhibits aerobic growth of P. denitrificans in a pH-dependent manner. Increased expression of a flavohemoglobin was observed in response to extracellular nitrite. Analysis of a mutant established flavohemoglobin to be involved in nitrite tolerance. Only ∼ 1.5% of the genome was differentially regulated in response to nitrite ‘stress’.