Long-term anaerobic survival of the opportunistic pathogen Pseudomonas aeruginosa via pyruvate fermentation
Long-term anaerobic survival of the opportunistic pathogen Pseudomonas aeruginosa via pyruvate fermentation
复制标题
DOI：
10.1128/jb.186.14.4596-4604.2004
复制
发表时间：
2004-07-01
影响因子：
3.2
通讯作者：
Schobert, M
中科院分区：
文献类型：
--
作者：
Eschbach, M;Schreiber, K;Schobert, M
反硝化和精氨酸发酵是由条件致病菌铜绿假单胞菌在囊性纤维化患者的肺部生物膜形成和感染期间进行的中心代谢过程。在全基因组范围内搜索厌氧代谢的其他组分，确定了代谢谷氨酸的NADH依赖性乳酸脱氢酶（ldhA）、磷酸转乙酰酶（pta）和乙酸激酶（ackA）的潜在基因。虽然单独的丙酮酸发酵不能维持铜绿假单胞菌的显著厌氧生长，但它为细菌提供了长达18天的长期存活的代谢能力。检测到的丙酮酸转化为乳酸和乙酸分别依赖于完整的ldhA和ackA-pta基因座的存在。结合报告基因融合分析和酶活性测量的DNA微阵列研究证明了ackA-pta启动子的anr-和ihfA-依赖的厌氧诱导。潜在的Anr和整合宿主因子结合位点进行了定位。丙酮酸依赖的厌氧长期生存被认为是显着减少在上午，和ihfA突变体。未观察到明显的ldhA受氧张力的调节。丙酮酸发酵是pH依赖性的。硝酸盐呼吸破坏丙酮酸发酵，而精氨酸发酵发生独立的丙酮酸利用。
Denitrification and arginine fermentation are central metabolic processes performed by the opportunistic pathogen Pseudomonas aeruginosa during biofilm formation and infection of lungs of patients with cystic fibrosis. Genome-wide searches for additional components of the anaerobic metabolism identified potential genes for pyruvate-metabolizing NADH-dependent lactate dehydrogenase (ldhA), phosphotransacetylase (pta), and acetate kinase (ackA). While pyruvate fermentation alone does not sustain significant anaerobic growth of P. aeruginosa, it provides the bacterium with the metabolic capacity for long-term survival of up to 18 days. Detected conversion of pyruvate to lactate and acetate is dependent on the presence of intact ldhA and ackA-pta loci, respectively. DNA microarray studies in combination with reporter gene fusion analysis and enzyme activity measurements demonstrated the anr- and ihfA-dependent anaerobic induction of the ackA-pta promoter. Potential Anr and integration host factor binding sites were localized. Pyruvate-dependent anaerobic long-term survival was found to be significantly reduced in am, and ihfA mutants. No obvious ldhA regulation by oxygen tension was observed. Pyruvate fermentation is pH dependent. Nitrate respiration abolished pyruvate fermentation, while arginine fermentation occurs independently of pyruvate utilization.