[目的]探索基因重组工程菌高密度发酵工艺,为得到高浓度和高产量的链球菌(Streotococcus)G蛋白(SPG)奠定基础.[方法]通过一级摇瓶、二级种子罐培养,以及将菌种转接到发酵罐并进行分批补料高密度培养,探讨了IPTG加入量等条件对发酵的影响,考察了接种量、氧气、pH、培养方式等发酵工艺.[结果]高密度发酵能得到至少80g/L的菌体,最高达到150 g/L,每升发酵液可得到1g的SPG.SPG高密度发酵的生产务件为:接种量10％,通气量1 vvm,溶氧控制在30％-45％,发酵过程控制pH7.0～7.2,IPTG的诱导浓度为0.2 mmoL/L,时间为4h,发酵后SPG总蛋白能达到菌体蛋白的20％以上.[结论]利用该生产工艺可得到高浓度菌体和高产量SPG.%[Objective] To explore the high cell density fermentation for the engineering bacteria, so as to lay foundation for obtaining high-concentration and high-yield SPG. [Method] The bacteria were transferred to a fermenting cylinder for a fed-batch high-density culture, the fermentation factors of IPTG dose, oxygen, pH and culture methods were studied. [Result] Under high cell density fermentation, 80 - 150 g/L bacteria were obtained, per liter of fermentation liquid contained 1 g SPG. The fermentation conditions of SPG were 10% IPTC dose, I vvm ventilation, 30% -45% dissolved oxygen, 7.0 -7.2 pH, 0.2 mmol/L IPTC concentration, and 4 h time, after fermentation, the total protein in SPG accounted for above 20% of the bacterial protein. [Conclusion] High-concentration and high-yield SPG could be obtained through this high cell density cultivation.
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