Regulation of hemin binding proteins by a novel transcriptional activator in Porphyromonas gingivalis.
Regulation of hemin binding proteins by a novel transcriptional activator in Porphyromonas gingivalis.
复制标题
牙龈卟啉单胞菌中新型转录激活剂对血红素结合蛋白的调节。
DOI：
10.1128/jb.00841-08
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发表时间：
2009
影响因子：
3.2
通讯作者：
Xie,Hua
中科院分区：
文献类型：
--
作者：
Wu,Jie;Lin,Xinghua;Xie,Hua
One of the features of the periodontal pathogenPorphyromonas gingivalisis the presence of complex iron acquisition systems that include anhmuYRSTUVlocus. HmuY and HmuR are hemin binding proteins required forP. gingivalisgrowth. Previous studies have demonstrated that expression of thehmulocus is regulated in response to environmental changes, such as growth phases. However, the mechanisms involved inhmugene regulation are poorly understood. Here we report that a novel transcriptional activator, PG1237, is required for the expression ofhumYandhumR, but not other iron acquisition-related genes, such asfetBandtlr, which also encode hemin binding proteins. Real-time reverse transcription-PCR analysis revealed that a mutation in the pg1237 gene decreased expression ofhmuYandhmuR149- and 25-fold, respectively, compared to that observed in the wild-type strain. In addition, differential expression ofhmuY,hmuR, and the pg1237 gene was found to be quorum-sensing dependent, such that higher expression levels of these genes were observed whenP. gingivaliswas grown at a lower cell density, such as that seen during the early exponential growth phase. This work demonstrates the involvement of a novel transcriptional activator, PG1237, in expression of thehmuoperon in a cell density-dependent fashion.
