Study on the virulent factors of Vibrio vulnificus

• Main Authors: Yj-Fang Teng, 鄧怡芳
• Other Authors: Ming-Chung Chang
• Format: Others
• Language: zh-TW
• Published: 2004
• Online Access: http://ndltd.ncl.edu.tw/handle/urz98t

碩士 === 國立成功大學 === 生物科技研究所碩博士班 === 92 === 　　Vibrio vulnificus is a marine Gram-negative bacteria that is recognized as a cause of fulminant primary septicemia, wound infections and acute self-limiting diarrhea. In our primary study, two genes (polS and polR) were cloned from vibrio vulnificus CKM-1. These two genes appeared to be arranged in an operon and shared sequence similarity with members of two-component signal transduction systems. PolS shows sequence homologous to sensor proteins and also contains a histidine residue highly conserved in the histidine kinase family of sensor protein. PolR is homologous to other regulatory proteins that bind to specific upstream activating elements to enhance transcription of genes with σ54 promoter. 　　Our previous northern blot analysis also indicated that PolR could be expressed as a bicistronic transcript from PolS; nevertheless PolR could also be markedly induced as a monocistronic transcript from its own promoter during exposure of bacteria to serum. In this study, reverse transcription polymerase chain reaction experiments were performed to confirm that PolR but not PolS could be specifically induced during exposure of bacteria to serum. In addition, whether PolR could autoregulate itself by binding its upstream region, which locates in PolS gene structure region, or σ54 could bind the expected σ54 promtor would be examined by electrophoresis mobility shift assay. Both PolS and PolR would be overexpressed and purified, and whether PolR could be phosphorylated by PolS or not would be investigated.