초록 |
Glycerol has become an attractive carbon source in biotechnology industry due to its low price and reduced state. However, glycerol has rarely been used as a carbon source in Saccharomyces cerevisiae because of its low utilization rate. In this study, we used glycerol as a main carbon source in S. cerevisiae to produce 1,2-propanediol. The introduction of two genes, mgs (methylglyoxal synthase) and gldA (glycerol dehydrogenase) from Escherichia coli, not only made S. cerevisiae produce 1,2-propanediol, but also increased the growth rate in glycerol and glycerol utilization rate of S. cerevisiae. Further increase of 1,2-propnaediol production and glycerol utilization rate were achieved by overexpression of endogenous GUT1 (glycerol kinase) and GUT2 (glycerol 3-phosphate dehydrogenase as well as GUP1 gene which involved in glycerol transport in S. cerevisiae. Lastly, we constructed newly glycerol dissimilation pathway as introducing glycerol dehydrogenase gene from Pichia angusta to S. cereviaise. By overexpressing six genes in S. cerevisiae, 0.98 g/l of 1,2-propanediol concentration was achieved in flask culture with 1%(v/v) glycerol as a main carbon source. |