Porphyromonas gingivalis is a keystone pathogen for periodontitis. The function of the GntR family transcription factor is poorly studied in P. gingivalis. Numerous processes govern bacterial growth. The survival and pathogenicity of P. gingivalis depend heavily on its capacity to acquire amino acids as nutritional sources. In this investigation, a GntR transcription factor, pg1007, was identified in P. gingivalis, the deletion of which significantly inhibited bacterial growth. The mutant strain also exhibited an increased extracellular activity of gingipains and acylpeptidyl oligopeptidase (AOP). Global gene expression profiling revealed that the expression levels of 59 genes were significantly altered in the Δpg1007 mutant, with an upregulation in gene expression for AOP, ABC transporters, and some membrane proteins. In addition, His-PG1007 protein was purified as a recombinant protein from Escherichia coli, and the conserved DNA sequence bound by it was determined using electrophoretic mobility shift assays and DNase I footprinting assays. Consequently, this study demonstrated that pg1007 is a crucial transcription factor in P. gingivalis and regulates the bacterial growth and activity of gingipains and AOP. These findings may enhance our understanding of the regulation of bacterial proliferation and protease activity in P. gingivalis.

中文翻译：

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牙龈卟啉单胞菌中的 GntR 家族转录因子调节细菌生长、酰基肽寡肽酶和牙龈蛋白酶活性

牙龈卟啉单胞菌是牙周炎的主要病原体。GntR 家族转录因子的功能在牙龈卟啉单胞菌中的研究很少。许多过程控制着细菌的生长。牙龈卟啉单胞菌的存活和致病性在很大程度上取决于其获取氨基酸作为营养来源的能力。在这项调查中，GntR 转录因子pg1007在P. gingivalis中被鉴定出来，其缺失显着抑制了细菌生长。突变菌株还表现出牙龈蛋白酶和酰基肽寡肽酶 (AOP) 的细胞外活性增加。全局基因表达谱显示 59 个基因的表达水平在Δpg1007突变体，AOP、ABC 转运蛋白和一些膜蛋白的基因表达上调。此外，His-PG1007 蛋白作为重组蛋白从大肠杆菌中纯化，并使用电泳迁移率变动分析和 DNase I 足迹分析确定与其结合的保守 DNA 序列。因此，这项研究表明pg1007是牙龈卟啉单胞菌中的一个关键转录因子，可调节牙龈蛋白酶和 AOP 的细菌生长和活性。这些发现可能会加强我们对牙龈卟啉单胞菌中细菌增殖和蛋白酶活性调节的理解。