Patent ID: 8790911

Claim:
An Escherichia coli bacterium which utilizes a carbon source to produce ethanol wherein said Escherichia coli bacterium expresses at least one pyruvate decarboxylase gene and at least one alcohol dehydrogenase gene from a bacterium of the genus Zymomonas ; further wherein said Escherichia coli bacterium comprises at least one genetic modification which provides for expression of a hemoglobin gene from a bacterium of the genus Vitreoscilla ; further wherein said Escherichia coli bacterium has increased production of ethanol on a cell mass basis compared to a genetically identical Escherichia coli bacterium which lacks at least one genetic modification which provides for expression of a hemoglobin gene from a bacterium of the genus Vitreoscilla ; and further wherein the expression of a hemoglobin gene from a bacterium of the genus Vitreoscilla produces a concentration of intracellular hemoglobin greater than 0 and less than 125 nmoles per gram wet weight of cells.