金黄色葡萄球菌的演相培养及A蛋白的提取

对金黄色葡萄球菌（Ｓｔａｐｈｙｌｏｃｏｃｃｕｓａｕｒｅｕｓ）ＣｏｗａｎⅠ的培养及Ａ蛋白提取工艺进行了优化研究．结果表明：在培养基中分别增加牛肉膏和蛋白陈的含量，有利于提高菌体生物量及Ａ蛋白的得率；少量酵母浸膏及葡萄糖对生物量及Ａ蛋白得率有促进作用，但当达到一定浓度时则会产生基质抑制作用；恒定培养过程的ｐＨ值有利于Ａ蛋白得率的增加，０．０３（）／ｍｉｎ通气量、搅拌速度２００ｒ／ｍｉｎ是能满足菌体生长的条件．根据Ａ蛋白耐热性强这一特性，采用加热法除去大部分杂质，然后用ＩｇＧ－琼脂糖凝胶亲和层析实现了Ａ蛋白的提纯．

FERMENTATION OF STAPHYLOCOCCUS AUREUS AND EXTRACTION OF PROTEIN A

The fermentation of Staphylococcus aureus Cowan I and extraction of SpA were studied.The results indicated that it would ho beneficial for biomass and SpA prodwtion to increase the amount of beef extract or peptone in medium.The addition of small amount of yeast extract or glucose could promote biomass and SpA production,but over addition could produce an inhibition in the production.The studies on pH,aeration rate and agitation speed showed that constant PH was good for SpA production,0.3()/min and 200 r/min could provide enough oxygen for the growth of bacteria in a 6 liter fermentor.Heating extraction method was used to remove the majority of impurity. Protein A was purified with IgG-sepharose affinity chromatography.