狐源豚鼠气单胞菌M12胞外产物特性研究

摘要

After the extracelluar production was extracted and concentrated from M12,the protein content,major components and toxicity of extracellular product (ECP) to Vero cells were detected.Pathogenicity of ECP was also researched by intramuscular injection and intestinal loop test.The results showed that the ECP's concentration is 0.67μg/mL and contained the esterase,protease,amylase and gelatinase with urease activity;ECP of M12 had acytotoxic effect on Vero cells and enterotoxin activities to intestinal tract;ECP was sensitive to temperature (optimum temperature is 37℃) and pH (optimum pH is 7.0);SDS-PAGE of ECP of M12 showed three proteins bands (36ku,42ku,and 68ku);The muscle tissue of the rabbits was observed to dissolve in leg followed by injection of ECP;the contents of intestine increased significantly after injection of ileum.In conclusion.M12 had many virulent factors with close relationship to its pathogenicity.%本研究提取、浓缩狐源豚鼠气单胞菌M12的胞外产物,并测定其蛋白含量、主要成分、对Vero细胞的毒性;通过肌肉注射和肠攀试验,探究其对家兔的致病性.结果表明,该菌浓缩的胞外产物浓度为0.67μg/mL,具有酯酶、蛋白酶、淀粉酶、明胶酶和脲酶活性:可致Vero细胞发生变圆、脱落等病变,且具有肠毒性;豚鼠气单胞菌M12对温度和pH较敏感,最适酶活性温度37℃,最适pH7.0;SDS-PAGE图谱发现36ku、42ku、68ku 3条蛋白条带;用浓缩豚鼠气单胞菌M12的胞外产物注射家兔腿部发现,肌肉组织溶解;回肠注射后肠道内容物含量显著增多.综上所述,豚鼠气单胞菌M12具有多种毒力因子,与该菌的致病性紧密相关.