Identification of Pseudomonas aeruginosa genes involved in virulence and anaerobic growth
Identification of Pseudomonas aeruginosa genes involved in virulence and anaerobic growth
复制标题
DOI：
10.1128/iai.02014-05
复制
发表时间：
2006-07-01
影响因子：
3.1
通讯作者：
Iglewski, Barbara H.
中科院分区：
文献类型：
--
作者：
Filiatrault, Melanie J.;Picardo, Kristin F.;Iglewski, Barbara H.
铜绿假单胞菌是一种革兰氏阴性机会致病菌，是宿主防御受损的患者发生急性和慢性感染的重要原因。有证据表明，在感染过程中，铜绿假单胞菌会遇到氧气限制，并存在于称为生物膜的微生物聚集体中。然而，很少有信息描述参与铜绿假单胞菌厌氧生长的基因及其与该病原体毒力的关联。为了鉴定厌氧生长所需的基因，使用随机转座子（Tn）诱变来筛选突变体，这些突变体证明无法使用硝酸盐作为末端电子受体进行厌氧生长。在筛选的约 35,000 个突变体中，发现 57 个突变体在使用硝酸盐的情况下无法厌氧生长。对被 Tn 破坏的基因的鉴定揭示了硝酸盐厌氧生长所需的 24 个不同基因座，其中包括一些以前与铜绿假单胞菌厌氧生长无关的基因。这些突变体中的一些能够使用亚硝酸盐和/或精氨酸厌氧生长，而五个突变体在任何测试条件下都不能厌氧生长。三种突变体在铜绿假单胞菌感染的生菜模型中毒力显着减弱。这些研究已经确定了对厌氧生长重要的新基因，并证明厌氧代谢影响铜绿假单胞菌的毒力。
Pseudomonas aeruginosa is a gram-negative, opportunistic pathogen and a significant cause of acute and chronic infections in patients with compromised host defenses. Evidence suggests that within infections P. aeruginosa encounters oxygen limitation and exists in microbial aggregates known as biofilms. However, there is little information that describes genes involved in anaerobic growth of P. aeruginosa and their association with virulence of this pathogen. To identify genes required for anaerobic growth, random transposon (Tn) mutagenesis was used to screen for mutants that demonstrated the inability to grow anaerobically using nitrate as a terminal electron acceptor. Of approximately 35,000 mutants screened, 57 mutants were found to exhibit no growth anaerobically using nitrate. Identification of the genes disrupted by the Tn revealed 24 distinct loci required for anaerobic growth on nitrate, including several genes not previously associated with anaerobic growth of P. aeruginosa. Several of these mutants were capable of growing anaerobically using nitrite and/or arginine, while five mutants were unable to grow anaerobically under any of the conditions tested. Three mutants were markedly attenuated in virulence in the lettuce model of P. aeruginosa infection. These studies have identified novel genes important for anaerobic growth and demonstrate that anaerobic metabolism influences virulence of P. aeruginosa.