首页 | 本学科首页   官方微博 | 高级检索  
   检索      


Growth-rate-independent production of recombinant glucoamylase by Fusarium venenatum JeRS 325
Authors:Wiebe M G  Robson G D  Shuster J  Trinci A P
Institution:School of Biological Sciences, 1.800 Stopford Building, University of Manchester, Manchester, M13 9PT, United Kingdom. marilyn.wiebe@man.ac.uk
Abstract:Most recombinant proteins generated in filamentous fungi are produced in fed-batch cultures, in which specific growth rate normally decreases progressively with time. Because of this, such cultures are more suited to the production of products that are produced efficiently at low-growth rates (e.g., penicillin) than to products which are produced more efficiently at high-growth rates (e. g., glucoamylase). Fusarium venenatum A3/5 has been transformed (JeRS 325) to produce Aspergillus niger glucoamylase (GAM) under the control of the Fusarium oxysporum trypsin-like protease promoter. No glucoamylase was detected in the culture supernatant during exponential growth of F. venenatum JeRS 325 in batch culture. In glucose-limited chemostat cultures, GAM concentration increased with decrease in dilution rate, but the specific production rate of GAM (g GAM g biomass](-1) h(-1)) remained approximately constant over the dilution-rate range 0.05 h to 0.19 h(-1), i.e., the recombinant protein was produced in a growth-rate-independent manner. The specific production rate decreased at dilution rates of 0.04 h(-1) and below. Specific production rates of 5.8 mg and 4.0 mg GAM g biomass](-1) h(-1) were observed in glucose-limited chemostat cultures in the presence and absence of 1 g mycological peptone L(-1). Compared to production in batch culture, and for the same final volume of medium, there was no increase in glucoamylase production when cultures were grown in fed-batch culture. The results suggested that a chemostat operated at a slow dilution rate would be the most productive culture system for enzyme production under this trypsin-like promoter.
Keywords:
本文献已被 PubMed 等数据库收录!
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号