The Role of Arginine Biosynthesis Gene in Vibrio vulnificus Infection

• Main Authors: Chia-Ju Wu, 吳佳儒
• Other Authors: Yu-Chung Chen
• Format: Others
• Language: zh-TW
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/mx42n9

碩士 === 嘉南藥理大學 === 生物科技系 === 103 === Vibrio vulnificus is a halophilic Gram-negative bacterium and always occurs in tropical and subtropical oceans. The bacteria can result in a serious, fulminant infection. Therefore, patients are dead within 2 days after hospitalization. V. vulnificus infection can cause primary septicemia via eating raw seafood with fever, shock and skin lesions, with the fatality rate about 50%. Wound infection can cause secondary septicemia and cellulitis, with the fatality rate about 25%. In our previous study, we found argD gene has cytotoxicity to macrophage, and its function was related to arginine synthesis from sequence analysis. Therefore, in this study, we focus on the influence of argD gene in V. vulnificus infection. Analysis of cytotoxicity, argD mutant had lower virulence to macrophage than the wild type and argD-complemented strains. The argD gene showed increased growth under arginine-limited conditions. In H2O2 resistance assay, argD mutant showed decreased resistance to H2O2. The intracellular survival rate of argD mutant inside macrophages also was lower than those of wild type and argD-complemented strains. In mouse experiment, argD mutant displayed reduced virulence. In conclusion, argD plays an important role in V. vulnificus infection.