Effect of pyruvate kinase gene deletion on the physiology of ATCC13032 under biotin-sufficient non-glutamate-producing conditions: Enhanced biomass production.

The effect of pyruvate kinase gene () deletion on the physiology of ATCC13032 was investigated under biotin-sufficient, non-glutamate-producing conditions. In a complex medium containing 100 g/L glucose, a defined deletion mutant, strain D1, exhibited 35% enhancement in glucose consumption rate, 37% increased growth and a 57% reduction in respiration rate compared to the wild-type parent. Significant upregulation of phosphoenolpyruvate (PEP) carboxylase and downregulation of PEP carboxykinase activities were observed in the D1 mutant, which may have prevented over-accumulation of PEP caused by the deletion.

Metabolic changes in a pyruvate kinase gene deletion mutant of Corynebacterium glutamicum ATCC 13032.

To investigate primary effects of a pyruvate kinase (PYK) defect on glucose metabolism in Corynebacterium glutamicum, a pyk-deleted mutant was derived from wild-type C. glutamicum ATCC13032 using the double-crossover chromosome replacement technique. The mutant was then evaluated under glutamic acid-producing conditions induced by biotin limitation.