Production of biobutanol from cellulose hydrolysate by the Escherichia coli co culture system.
The commercialization of the n butanol bioprocess is largely dependent on the price of feedstocks. Renewable cellulose appears to be an appealing feedstock. The microbial production of n butanol still remains challenging because of the limited availability of intracellular NADH. To address this issue, an Escherichia coli strain carrying the clostridial CoA dependent pathway was supplied with heterologous formate dehydrogenase. With the cellulose hydrolysate of rice straw, this single strain produced cellulosic biobutanol with a production yield at 35% of the theoretical and a productivity of 0.093 g L( 1) h( 1) In an alternative method, the production involved a co culture system consisting of two separate strains provided with the full CoA dependent pathway. This system achieved a production yield and productivity reaching 62.8% of the theoretical and 0.163 g L( 1) h( 1) respectively. The result indicates that the E. coli co culture system is technically promising for the production of cellulosic biobutanol.
FEMS microbiology letters