米曲霉发酵液中蛋白动态变化的研究

Expression Changes of Proteins in Fermentation Broth of Aspergillus oryzae

摘要:

本文利用葡萄糖和吐温80作为额外碳源培养米曲霉，对其生物量积累，胞链接蛋白以及发酵液蛋白随培养时间的变化情况进行了研究。以葡萄糖作为额外碳源时，米曲霉生物量积累速度较快，在培养24 h已达最大值，为31.97 g/L；当米曲霉以吐温80作为额外碳源时菌体积累较慢，在96 h时达到最大值，为11.15 g/L。发酵液中蛋白总量在以葡萄糖作为额外碳源时比以吐温80时低。以吐温80作为额外碳源时，胞链结蛋白在72 h达到最大值的5.65 mg/g，当以葡萄糖作为额外碳源时，米曲霉胞链结蛋白含量在48 h达到最大值，为1.71 mg/g。利用SDS-PAGE检测192 h内胞连接蛋白质的表达与发酵液中的蛋白质的含量变化与利用lowry法测定的蛋白质含量具有一致的变化趋势：在米曲霉的快速生长期和稳定期时胞链结蛋白种类增加，在衰退期胞链结蛋白种类减少。

Abstract:

In this paper, biomass accumulation, dynamic expression of proteins in fermentation broth of Aspergillus oryzae were studied when glucose or tween 80 were used as additional carbon sources. When glucose was used as additional carbon source, biomass accumulation of A.oryzae was faster than tween 80 and reached the maximum of 31.97 g/L at 24 h, but accumulation of A.ryzae was slow when tween 80 was used, which reached the maximum of 11.15 g/L at 96 h. Total proteins in fermentation broth was higher with glucose as additional carbon source. Cell-bound proteins reached the maximum value of 5.65 mg/g at 72 h with tween 80 as additional carbon source, while cell-bound proteins reached the maximum of 1.71 mg/g at 48 h with glucose as additional carbon source. Expression of cell-bound proteins detected by SDS-PAGE within 192 h showed that cell-bound proteins increassed at the rapid growth and stationary phages, and reduced at the recession phage.which was in consistent with protein contents measured by the Lowry method.