Tuyển tập các báo cáo nghiên cứu về hóa học được đăng trên tạp chí hóa hoc quốc tế đề tài : Glycerol conversion to 1, 3-Propanediol is enhanced by the expression of a heterologous alcohol dehydrogenase gene in Lactobacillus reuteri | o AMB Express a SpringerOpen Journal Vaidyanathan et al. AMB Express 2011 1 37 http content 1 1 37 ORIGINAL Open Access Glycerol conversion to 1 3-Propanediol is enhanced by the expression of a heterologous alcohol dehydrogenase gene in Lactobacillus reuteri Hema Vaidyanathan1 Vijayalakshmi Kandasamy1 Gopi Gopal Ramakrishnan1 KB Ramachandran2 Guhan Jayaraman2 and Subramanian Ramalingam1 Abstract In this work Lactobacillus reuteri has been metabolically engineered for improving 1 3-propanediol 1 3-PD production by the expression of an Escherichia coli alcohol dehydrogenase yqhD that is known to efficiently convert the precursor 3-hydroxypropionaldehyde 3-HPA to 1 3-PD. The engineered strain exhibited significantly altered formation rates for the product and other metabolites during the fermentation. An increase in the 1 3-PD specific productivity of 34 and molar yield by 13 was achieved in the clone relative to the native strain. A concomitant decrease in the levels of toxic intermediate 3-HPA was observed with the specific productivity levels being 25 lesser than that of the native strain. Interestingly the recombinant strain exhibited elevated rates of lactate and ethanol formation as well as reduced rate of acetate production compared to the native strain. The preferential utilization of NADPH by YqhD with a possible decrease in the native 1 3-PD oxidoreductase NADH-dependent activity could have resulted in the diversion of surplus NADH towards increased lactate and ethanol productivities. Keywords 1 3-propanediol oxidoreductase YqhD NADPH 3-HPA L. reuteri Introduction Biological processes are eco-friendly and sustainable alternatives to conventional chemical processes for production of several industrially important bulk chemicals like succinic acid lactic acid 1 3-propanediol 1 4-butanediol etc. Biebl et al. 1998 Chotani et al. 2000 Song and Lee 2006 . Such processes could be economically viable if they are based on renewable feedstocks. .
