It is an object of the present invention to provide a method of producing succinic acid that overcomes many of the disadvantages of the prior art.

It is another object of the present invention to provide a fermentation process that produces high yields of succinic acid(cas:110-15-6). A feature of the invention is the utilization of bacterial genomes containing a plurality of mutant genes to enable the method. An advantage of the invention is that bacteria can be readily manipulated to produce the plurality of mutants. Alternatively, bacteria already containing the plurality of mutations can be utilized without further manipulation.

Still another object of the present invention is to provide a process for manipulating bacteria to produce large amounts of succinic acid(cas:110-15-6). A feature of the invention is the disruption of the normal regulation of sugar metabolism in the bacteria. An advantage of the invention is the ability to manipulate a variety of bacteria to facilitate relatively high product-to-growth substrate ratios (i.e., at or above 1:1) in fermentation processes for producing succinic acid. Another advantage of the invention is the ability to utilize bacteria which become glucose metabolisers and non-glucose metabolisers.

Yet another object of the present invention is to produce succinic acid(cas:110-15-6) fermentatively. A feature of the invention is the utilization of bacteria containing altered phosphotransferase (pts) systems, pyruvate formate lyase (pfl) systems, and lactate dehydrogenase (ldh) systems. An advantage of the invention is that the bacteria can be derived from many genera which use these enzyme systems for sugar fermentation.

Briefly a method of producing succinic acid(cas:110-15-6) from industrial-grade hydrolysates is provided, comprising: supplying an organism that contains mutations for the genes ptsG, pflB, and ldhA; allowing said organism to accumulate biomass; and allowing said organism to metabolize the hydrolysate.

Also provided is a bacteria mutant characterized in that it produces succinic acid(cas:110-15-6) from substrate contained in industrial-grade hydrolysate in a ratio of between 0.6:1 and 1.3:1 succinic acid to substrate (e.g., between 0.6 and 1.3 grams succinic acid per gram of total sugar consumed).