The present invention provides a genetically modified lactic acid bacterium capable of producing diacetyl under aerobic conditions. Additionally the invention provides a method for producing diacetyl using the genetically modified lactic acid bacterium under aerobic conditions in the presence of a source of iron-containing porphyrin and a metal ion selected from Fe3+, Fe2+ and Cu2+. The lactic acid bacterium is genetically modified by deletion of those genes in its genome that encode polypeptides having lactate dehydrogenase (E.C 18.104.22.168/E.C.22.214.171.124); α-acetolactate decarboxylase (E.C 126.96.36.199); water-forming NADH oxidase (E.C. 188.8.131.52); phosphotransacetylase (E.C.184.108.40.206) activity; and optionally devoid of or deleted for genes encoding polypeptides having diacetyl reductase ((R)-acetoin forming; EC: 220.127.116.113); D-acetoin reductase; butanediol dehydrogenase ((R,R)-butane-2,3-diol forming; E.C. 18.104.22.168/1.1.1.-) and alcohol dehydrogenase (E.C. 22.214.171.124) activity. The invention provides for use of the genetically modified lactic acid bacterium for the production of diacetyl and a food product.
|IPC||C12N 15/ 74 A I|
|Country||International Bureau of the World Intellectual Property Organization (WIPO)|
|Publication status||Published - 13 Apr 2017|