High cell density culture of recombinant E.coli to produce Pseudomonas aeruginosa exoprotein A
DONG Yong-qian,XUAN Jun-wen,FENG Yi-yang,et al.(Lanzhou Institute of Biological Products,Lznzhou 730046,China)
To culture recombinant E.coli in high cell density to produce Pseudomonas aeruginosa exoprotein A(rEPA).30L autocontrol fermenter made by Shanghai GaoJi Corperation and fed-batch culture technology were used in this experiment,adding nitrogen nutrition in batches,keeping glucose concentration at low level,dissolved oxygen at 30% to 40%,pH at about 7.00 throughout the culture and induced at middle stage of logarithm growth stage.When not induced,the final cell density is 44,when induced,the final cell density is 36,the expressed rEPA protein content in the supernatant is 28.1% of whole supernatant proteins,and expressed protein in bacteria is 4.7% of whole bacteria proteins.This study provides foundation for large-scale production of rEPA.
【CateGory Index】： R378.99