Patent ID: 8216816

Claim:
A method for the biogenic production of ethanol, comprising: culturing an engineered cyanobacterium in a culture medium in the presence of light and CO 2 , wherein said cyanobacterium comprises a recombinant pyruvate decarboxylase gene and at least two copies of a recombinant alcohol dehydrogenase gene encoding an NADPH-dependent alcohol dehydrogenase (EC 1.1.1.2), wherein said NADPH-dependent alcohol dehydrogenase is at least 95% identical to SEQ ID NO: 2, wherein the expression of said recombinant alcohol dehydrogenase gene is increased relative to the expression of said recombinant pyruvate decarboxylase gene, and wherein the amount of ethanol released into said culture medium by said engineered cyanobacterium is equal to or greater than 10 mg/L/hr.