METHODS AND ORGANISMS FOR THE GROWTH-COUPLED PRODUCTION OF SUCCINATE

摘要

The invention provides a non-naturally occurring microorganism comprising one or more gene disruptions encoding an enzyme associated with growth-coupled production of succinate when an activity of the enzyme is reduced, whereby the one or more gene disruptions confers stable growth-coupled production of succinate onto the non- naturally occurring microorganism. Also provided is a non-naturally occurring microorganism comprising a set of metabolic modifications obligatory coupling succinate production to growth of the microorganism, the set of metabolic modifications comprising disruption of one or more genes selected from the set of genes comprising: (a) adhE, ldhA; (b) adhE, ldhA, acka-pta; (c) pfl, ldhA; (d) pfl, ldhA, adhE; (e) acka-pta, pykF, atpF, sdhA; (f) acka-pta, pykF, ptsG, or (g) acka-pta, pykF, ptsG, adhE, ldhA, or an ortholog thereof, wherein the microorganism exhibits stable growth-coupled production of succinate. Additionally provided is a non-naturally occurring microorganism having the genes encoding the metabolic modification (e) acka-pta, pykF, atpF, sdhA that further includes disruption of at least one gene selected from pyka, atpH, sdhB or dhaKLM; a non-naturally occurring microorganism having the genes encoding the metabolic modification (f) ackA-pta, pykF, ptsG that further includes disruption of at least one gene selected from pykA or dhaKLM, or a non-naturally occurring microorganism having the genes encoding the metabolic modification (g) ackA-pta, pykF, ptsG, adhE, ldhA that further includes disruption of at least one gene selected from pykA or dhaKLM. The disruptions can be complete gene disruptions and the non-naturally occurring organisms can include a variety of prokaryotic or eukaryotic microorganisms. A method of producing a non-naturally occurring microorganism having stable growth-coupled production of succinate also is provided. The method includes: (a) identifying in silico a set of metabolic modifications requiring succinate production during exponential growth, and (b) genetically modifying a microorganism to contain the set of metabolic modifications requiring succinate production.