Altaras N E, Cameron D C
Department of Chemical Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706-1691, USA.
Appl Environ Microbiol. 1999 Mar;65(3):1180-5. doi: 10.1128/AEM.65.3.1180-1185.1999.
1,2-Propanediol (1,2-PD) is a major commodity chemical that is currently derived from propylene, a nonrenewable resource. A goal of our research is to develop fermentation routes to 1,2-PD from renewable resources. Here we report the production of enantiomerically pure R-1,2-PD from glucose in Escherichia coli expressing NADH-linked glycerol dehydrogenase genes (E. coli gldA or Klebsiella pneumoniae dhaD). We also show that E. coli overexpressing the E. coli methylglyoxal synthase gene (mgs) produced 1,2-PD. The expression of either glycerol dehydrogenase or methylglyoxal synthase resulted in the anaerobic production of approximately 0.25 g of 1,2-PD per liter. R-1,2-PD production was further improved to 0.7 g of 1,2-PD per liter when methylglyoxal synthase and glycerol dehydrogenase (gldA) were coexpressed. In vitro studies indicated that the route to R-1,2-PD involved the reduction of methylglyoxal to R-lactaldehyde by the recombinant glycerol dehydrogenase and the reduction of R-lactaldehyde to R-1, 2-PD by a native E. coli activity. We expect that R-1,2-PD production can be significantly improved through further metabolic and bioprocess engineering.
1,2 - 丙二醇（1,2 - PD）是一种主要的商品化学品，目前由不可再生资源丙烯制得。我们研究的目标是开发从可再生资源生产1,2 - PD的发酵途径。在此，我们报道了在表达与NADH相关的甘油脱氢酶基因（大肠杆菌gldA或肺炎克雷伯菌dhaD）的大肠杆菌中，从葡萄糖生产对映体纯的R - 1,2 - PD。我们还表明，过表达大肠杆菌甲基乙二醛合酶基因（mgs）的大肠杆菌能产生1,2 - PD。甘油脱氢酶或甲基乙二醛合酶的表达导致厌氧条件下每升产生约0.25克1,2 - PD。当甲基乙二醛合酶和甘油脱氢酶（gldA）共表达时，R - 1,2 - PD的产量进一步提高到每升0.7克1,2 - PD。体外研究表明，R - 1,2 - PD的生成途径包括重组甘油脱氢酶将甲基乙二醛还原为R - 乳酸醛，以及大肠杆菌的天然活性将R - 乳酸醛还原为R - 1,2 - PD。我们期望通过进一步的代谢和生物过程工程能够显著提高R - 1,2 - PD的产量。
