六株金黄色葡萄球菌生化特性、胞外分泌蛋白及肠毒素基因分析

Characteristics of six Staphylococcus aureus strains and analysis of secreted exoproteins and enterotoxin genes

[目的]了解和比较6株金黄色葡萄球菌生化特性、胞外分泌蛋白及肠毒素基因等特征,为揭示其在感染疾病发生中的机制提供基础.[方法]采用API检测试纸条,SDS-PAGE电泳和PCR等方法研究6株金黄色葡萄球菌.[结果]6株菌株都可发酵葡萄糖、蔗糖和甘露糖,其中,5株菌株可分解精氨酸,4株菌株尿酶试验显阳性,2株菌株可分解山梨醇、苦杏仁苷和阿拉伯糖,1株菌株H2S试验呈阳性,1株菌株可分解肌醇和密二糖;SDS-PAGE显示4株菌株可产生多种胞外分泌蛋白;5对特异性传统肠毒素基因引物对6株菌株进行PCR扩增,其中4株携带肠毒素基因.[结论]研究结果揭示了肠毒素的产生与胞外其它分泌蛋白和毒素在一定程度上具有关联性.

Objective：To compare the colony morphology,the biochemical characteristics,the secreted exoproteins and enterotoxin genes of six Staphylococcus aureus strains for further exploring the cells and host interactions mechanisms.Methods： The API detection kits,SDS-PAGE and PCR methods are used.Results： The results indicate that the glucose,sucrose and mannitol could be fermented by all the six strains.Five strains could utilize arginine.Four strains could hydrolyze urea.One strain could produce H2S.One strain could ferment inositol and melibiose.Two strains could ferment sorbitol,amygdalin and arabinose.The total exoproteins of six strains are analyzed by using SDS-PAGE.The bands of four strains could produce the main types of exotoxins and exoenzymes.The genes encoding the enterotoxins A to E are detected by using specific enterotoxins gene primers in a PCR protocol.Four strains are demonstrated as enterotoxins-producing strains.Conclusion： This study reveales a good correlation between enterotoxins and other exoproteins.