Study on the oxidative stress responses of a major periodontopathogenic bacteria

一种主要牙周病原菌氧化应激反应的研究

• 批准号: 16591831
• 负责人: OHARA Naoya
• 金额: $ 2.3万
• 依托单位: Nagasaki University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2004
• 资助国家: 日本
• 起止时间: 2004 至 2005
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-16591831/
• 关键词: anaerobe; periodontitis; Porphyromonas gingivalis; oxidative stress

Inspection of genomic DNA sequence of the oral anaerobe Porphyromonas gingivalis reveals that the microorganism possesses the peroxide-sensing transcription activator OxyR, but not the superoxide-sensing transcription factor SoxR. Oxidative stress-responsive proteins in the microorganism were investigated using two dimensional gel electrophoresis and it was found that two proteins, SOD and AhpC were predominantly upregulated in oxidative conditions. In P. gingivalis oxyR mutant these two proteins were not induced by treatment with hydrogen peroxide under aerobic conditions. P.gingivalis sod and ahpC were positively regulated by OxyR. Putative -35 boxes of these promoters were found immediately adjacent to their putative OxyR binding sequences. Moreover, the promoter regions of sod and ahpC had the ability to bind P.gingivalis OxyR protein. These results demonstrate that P.gingivalis sod is one of the OxyR regulons, suggesting that OxyR functions as an intracellular redox sensor rather than a peroxide sensor in this organism.The new protein (UstA) was also identified in this study. Expression of UstA was upregulated in stationary phase or by exposure to atmospheric oxygen. The UstA-encoding gene (ustA) was located upstream of a homologue of the usp gene. The ustA gene appeared to be transcribed in a monocistronic fashion. The ustA mutant grew slower than the wild type parent strain, resulting in a lower yield in stationary phase. Furthermore, in this mutant, the expression levels of SOD, Tpr, and Trx were markedly higher than those in the wild type. The ustA mutant was more resistant to diamide, a thiol-specific oxidant, than the wild type. In addition, the ustA mutation suppressed hypersensitivities of the oxyR mutant to diamide,. metronidazole, and mitomycin C. These results suggest that UstA may play a significant role in oxidative stress responses in the bacterium.

对口腔厌氧菌牙龈卟啉单胞菌基因组DNA序列的检测表明，该微生物具有过氧化氢敏感转录激活子OxyR，但不具有超氧化物敏感转录因子SoxR。利用双向凝胶电泳法对微生物中的氧化应激响应蛋白进行了研究，发现在氧化条件下，SOD和AhpC两种蛋白的表达显著上调。在牙龈假单胞菌oxR突变体中，这两种蛋白在好氧条件下不受过氧化氢处理的诱导。牙龈假单胞菌的SOD和ahpC受OxyR正向调节。在其推测的OxyR结合序列附近发现了推定的-35盒启动子。此外，超氧化物歧化酶和ahpC启动子区域具有与牙龈假单胞菌OxyR蛋白结合的能力。这些结果表明，牙龈假单胞菌sod是OxyR调节子之一，这表明OxyR在该生物体中作为细胞内的氧化还原感受器而不是过氧化感受器发挥作用。在稳定期或暴露于大气氧气中，USTA的表达上调。USTA编码基因(USTA)位于USP基因同源物的上游。USTA基因似乎是以单顺反子方式转录的。突变株生长较慢，稳定期产量较低。此外，在该突变体中，SOD、Tpr和Trx的表达水平显著高于野生型。与野生型相比，Usta突变体对联胺的抗性更强。联胺是一种硫醇特有的氧化剂。此外，USTA突变还抑制了oxR突变体对联胺的过敏反应。这些结果表明，USTA可能在细菌的氧化应激反应中发挥重要作用。

项目成果

The novel stationary-phase-upregulated protein of Porphyromonas gingivalis influences the production of superoxide dismutase, thiol peroxidase and thioredoxin.

牙龈卟啉单胞菌的新型稳定期上调蛋白影响超氧化物歧化酶、硫醇过氧化物酶和硫氧还蛋白的产生。

• 发表时间: 2005
• 期刊: Microbiology-SGM 151・3
• 作者: Matsumoto S;Kanekiyo M;Ami Y;Oiso R;松本 壮吉;松本 壮吉;Zhang Z;Soejima H;Arima T;Yamasaki Y;Soejima H;Haruta M;副島英伸;Naoya Ohara;Marika Naito;Yuichiro Kikuchi
• 通讯作者: Yuichiro Kikuchi

Superoxide dismutase-encoding gene of the obligate anaerobe Porphyromonas gingivalis is regulated by the redox-sensing transcription activator OxyR

• DOI: 10.1099/mic.0.28537-0
• 发表时间: 2006-04-01
• 期刊: MICROBIOLOGY-SGM
• 影响因子: 2.8
• 作者: Ohara, N;Kikuchi, Y;Nakayama, K
• 通讯作者: Nakayama, K

Novel stationary-phase-upregulated protein of Porphyromonas gingivalis influences production of superoxide dismutase, thiol peroxidase and thioredoxin

• DOI: 10.1099/mic.0.27589-0
• 发表时间: 2005-03-01
• 期刊: MICROBIOLOGY-SGM
• 影响因子: 2.8
• 作者: Kikuchi, Y;Ohara, N;Nakayama, K
• 通讯作者: Nakayama, K