Increased Ethanol Production By Genetic Engineering Of Microorganisms To Express Hemoglobin

摘要

The present disclosure describes novel bacterial strains which express a pyruvate decarboxylase gene and at least one alcohol dehydrogenase gene from a bacteria of the genus Zymomonas and also express a hemoglobin gene from a bacteria of the genus Vitreoscilla. The present disclosure further describes methods for producing fermentation products with a microorganism which expresses a pyruvate decarboxylase gene and at least one alcohol dehydrogenase gene from a bacteria of the genus Zymomonas and also express a hemoglobin gene from a bacteria of the genus Vitreoscilla. Further the present disclosure describes methods for increasing production of a fermentation product comprising genetically engineering a microorganism which expresses a xylose isomerase gene to also express a hemoglobin gene from a bacteria of the genus Vitreoscilla.

主权项

1. A method for increasing production of ethanol on a cell-mass basis comprising:
(a) providing a microorganism which utilizes a carbon source to produce ethanol wherein said microorganism expresses a xylose isomerase gene; (b) genetically modifying said microorganism, wherein said modifying comprises at least one genetic modification which provides for expression of a hemoglobin gene from a bacterium of the genus Vitreoscilla; and (c) contacting the modified hemoglobin expressing microorganism of step (b) with at least one carbon source comprising xylose under substantially anaerobic conditions, wherein production of ethanol is greater on a cell-mass basis after said microorganism is genetically modified to provide for expression of said hemoglobin than before said microorganism is genetically modified to provide for expression of said hemoglobin.