摘要
用含不同浓度铁离子的培养基培养嗜水气单胞菌J-1株,36h时检测细菌含量以及毒素、蛋白酶、载铁体的表达量。发现菌液的浓度随着Fe2+浓度的升高而升高,而毒力因子的表达量则相反,当Fe2+的加入浓度为0时,毒素、蛋白酶、载铁体的表达量达最大值。用SDS-PAGE电泳及免疫转印分析细菌的外膜蛋白(OMP),嗜水气单胞菌J-1株在表达载铁体的同时多表达一条OMP,其相对分子质量为71.7×103,应为载铁体的受体。此时,经ELISA检测细菌菌体及抽取物S蛋白为阴性;经超薄切片电镜观察,菌体无S层结构。随着铁离子浓度的降低,J-1株毒素、蛋白酶及载铁体的表达增多,菌体S蛋白消失,并产生相应的OMP条带,显示铁对嗜水气单胞菌毒力因子的产生具有重要影响。
Aeromonas hydrophila J 1 strain was cultured in mediums containing different concentrations of iron,and virulent factors of toxin,protease and siderophore were detected at 36 h.It was shown that the bacteria concentration increased and expression of virulent factors decreased with the increase of iron concentration.If no iron was added,maximum expression of toxin,proteases and siderophore were obtained.When iron was added at 0 0 8 μg/mL,the expression of toxin,protease and siderophore varied negatively with the iron concentration.But further variation was not observed when iron was added at 0 8 3 2 μg/mL.SDS PAGE and immuno blotting demonstrated that J 1 strain expressed one outer membrane protein(OMP)band with MW of 71 7×10 3,which was considered as siderophore receptor.When J 1 expressed siderophore,S protein was not detected in J 1 cells by electron microscopy and ELISA.It suggested that iron is an important environment factor that affects the virulence of Aeromonas hydrophila .
出处
《南京农业大学学报》
CAS
CSCD
北大核心
1999年第1期83-86,共4页
Journal of Nanjing Agricultural University
基金
国家九五攻关子课题
关键词
嗜水气单胞菌
铁
毒素
蛋白酶
载铁体
Aeromonas hydrophila
iron
siderophore
outer membrane protein