The RprY response regulator of Porphyromonas gingivalis
The RprY response regulator of Porphyromonas gingivalis
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DOI：
10.1111/j.1365-2958.2007.05717.x
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发表时间：
2007-05-01
影响因子：
3.6
通讯作者：
Duncan, Margaret J.
中科院分区：
文献类型：
--
作者：
Duran-Pinedo, Ana E.;Nishikawa, Kiyoshi;Duncan, Margaret J.
牙龈卟啉单胞菌是一种与慢性成人牙周炎相关的革兰氏阴性口腔厌氧菌。它的生态位是牙龈缝隙，在那里生物体适应感染过程的挑战，如宿主防御和细菌产物。细菌对环境变化的反应部分受双组分信号转导系统的调节。在牙龈卟啉单胞菌的基因组中注释了几个完整的系统，以及编码RprY同源物的孤儿调节因子，RprY是来自脆弱拟杆菌的反应调节因子。为了确定激活牙龈卟啉单胞菌中RprY的环境线索，我们使用了几种策略来识别其调节子。从基因表达和DNA-蛋白质结合试验的结果确定了参与运输功能或与氧化应激相关的靶基因，并表明RprY可以作为激活剂和阻遏物。RprY能激活初级钠泵、NADH：泛醌氧化还原酶（NQR），RprY蛋白还能与来自B的nqrA基因启动子区相互作用。脆弱弧菌和霍乱弧菌。鉴于牙龈出血和宿主防御细胞的浸润是牙周感染的症状，从血液中释放的铁产物和多形核白细胞中的活性氧可能是RprY调节子的潜在诱导物。
Porphyromonas gingivalis is a Gram-negative oral anaerobe associated with chronic adult periodontitis. Its ecological niche is the gingival crevice, where the organism adapts to the challenges of the infectious process such as host defence and bacterial products. Bacterial responses to environmental changes are partly regulated by two-component signal transduction systems. Several intact systems were annotated in the genome of P. gingivalis, as well as an orphan regulator encoding a homologue of RprY, a response regulator from Bacteroides fragilis. With the goal of defining the environmental cues that activate RprY in P. gingivalis, we used several strategies to identify its regulon. Results from gene expression and DNA-protein binding assays identified target genes that were either involved in transport functions or associated with oxidative stress, and indicated that RprY can act as an activator and a repressor. RprY positively activated the primary sodium pump, NADH : ubiquinone oxidoreductase (NQR), and RprY protein also interacted with the promoter regions of nqrA genes from B. fragilis and Vibrio cholerae. Given that gingival bleeding and infiltration of host defence cells are symptoms of periodontal infection, iron products released from blood and reactive oxygen species from polymorphonuclear leucocytes may be potential inducers of the RprY regulon.