Fed-batch culture of recombinant Saccharomyces cerevisiae for glucose 6-phosphate dehydrogenase production

摘要

We examined glucose 6-phosphate dehydrogenase (G6PD)production by fed-batch cultivation,using a recombinant strain of Saccharomyces cerevisiae W303-181 overexpressing this enzyme.The cultivations were carried out in a 3 L fermenter at pH 5.7,30 deg C,2.0 vvm aeration,200 rpm agitation and an inoculum concentration of 1.0 g/L.The volume of the culture medium in the fed-batch process varied from 1.333 to 2.0.L,due to the addition of 15.0 g/L glucose solution during 5 h.Different feeding rates were studied (exponentially increasing and decreasing feeding rates),and the feeding profile was determined by values of the parameter K (time constant),namely:0.2,0.5 and 0.8 h~(-1).The best enzyme production (847 U/L)was obtained with an exponentially increasing feeding rate and K=0.2 h~(-1).The results attained also showed that this process is promising for G6PD production.