• Biotechnology and Bioprocess Engineering:BBE
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• v.3 no.2
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• pp.109-111
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• 1998

The effect of dissolved oxygen concentration on the metabolism of glucose in Pseudomonas putida BM014 was investigated. Glucose was completely converted to 2-ketogluconate via extracellular oxidative pathway and then taken up for cell growth under the condition of sufficient dissolved oxygen concentration. On the other hand, oxygen limitation below dissolved oxygen tension (DOT) value of 20% of air saturation caused the shift of glucose metabolism from the extracellular oxidative pathway to the intracellular phosphorylative pathway. Specific activities of hexokinase and gluconate kinase in intracellular phosphorylation pathway decreased as the DOT increased, while 2-ketogluconokinase activity in extracellular oxidative pathway increased under the same condition. This result can be usefully applied to microbial transformation of glucose to 2-ketogluconate, the synthetic precursor for iso-vitamine C, with almost 100% yield via extracellular oxidation by simple DOT control.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.3
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• pp.394-398
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• 2002

Acetic acid bacteria have been isolated from running high-acid vinegar fermentation. The color of the isolated colony was beige-yellowish. Isolated cell was rod-shaped, small, pale, absolutely aerobic and gram-negative. Microscopically the cells appeared as non-motile and non-flagellated, preferentially occuring in pairs. The optimum temperature and pH for culture were 30$\^{C}$ and 2.7, respectively. The strain was able to grow in the presence of acetic acid, ethanol and glucose. Ethanol was oxidized to acetic acid which was not oxidized any more. The isolated strain utilized glucose, fructose, maltose, sucrose, mannitol and sorbitol as carbon source. Cellulose formation was not detected on bouillon. The DNA (G +C) content of isolated strain was determined to be 56.2 mol%. The strain isolated from industrial vinegar fermentation was identified as Gluconacetobacter europaeus.