Molecular biochemical study on pathogenesis, especially toxin and adhesive factor, of Vibrio parahaemolyticus

本研究的目的是研究副溶血性弧菌的详细致病机理。取得了以下研究结果：1.耐热直接溶血素及其相关溶血素的研究：我们发现，直接溶血素通过其N端区识别一个特定的受体，然后诱导一个25 kDa的蛋白磷酸化，导致溶血。我们还发现TDH、TRH和尿素酶基因紧密连锁，并存在于50kb片段(致病岛？)内。黏附因子研究：我们鉴定了CHA(细胞相关血凝素)为副溶血性弧菌的黏附因子。CHA是一个由26 kDa的4个亚基组成的四聚体蛋白，其受体是一个分子量为17kDa的糖共轭化合物。其他结果：我们还证实了副溶血性弧菌在体外培养细胞系统中的侵袭性，这可能解释了该细菌引起败血症的原因。发展和评价了检测TDH和/或TRH的方法，并发现了一种新的TdH变异体。

The purpose of this research is to investigate detailed pathogenesis of Vibrio parahaemolyticus. Following results were obtained.1. Studies on thermostable direct hemolysin (TDH) and TDH-related hemolysin (TRH) : We found that TDH recognized a specific receptor through its N-teminal region and then induced phosphorylation of a 25 kDa protein, resulting in hemolysis. We also found that genes for TDH,TRH and urease are closely linked and present within 50kb-fragment (a pathogenicity island? ).2. Studies on adhesive factors : We identified cHA (cell-associated hemagglutinin) as an adhesive factor of V.parahaemolyticus. The cHA is a tetrameric protein consisting of 4 subunit of 26kDa and the receptor for cHA is a glycoconjugate having molecular weight of 17kDa.3. Other results : We also demonstrated the invasive character of V.parahaemolyticus in vitro cultured cell system, which may explain the cause of septicemia due to this organism. The methods detecting TDH,TRH or both were developed and evaluated, and a new variant of TDH was found.