Use of a Gluconobacter frateurii mutant to prevent dihydroxyacetone accumulation during glyceric acid production from glycerol.

Research Institute for Innovation in Sustainable Chemistry, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki, Japan.
Bioscience Biotechnology and Biochemistry (Impact Factor: 1.27). 11/2010; 74(11):2330-2.
Source: PubMed

ABSTRACT To prevent dihydroxyacetone (DHA) by-production during glyceric acid (GA) production from glycerol using Gluconobacter frateurii, we used a G. frateurii THD32 mutant, ΔsldA, in which the glycerol dehydrogenase subunit-encoding gene (sldA) was disrupted, but ΔsldA grew much more slowly than the wild type, growth starting after a lag of 3 d under the same culture conditions. The addition of 1% w/v D-sorbitol to the medium improved both the growth and the GA productivity of the mutant, and ΔsldA produced 89.1 g/l GA during 4 d of incubation without DHA accumulation.

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