A method for the determination of pyruvate carboxylase activity during theglutamic acid fermentation with Corynebacterium glutamicum

A discontinuous lactate dehydrogenase coupled assay is described for the ev aluation of the pyruvate carboxylase activity (Pc, EC 6.3.1.1) in a glutama te overproducing strain of Corynebacterium glutamicum. After an initial per meabilisation period of the cells, the method consisted of the fluorometric determination of the remaining pyruvate level after transformation into ox aloacetate by the endogenous Pc. The assay was demonstrated to be powerful and enabled the determination of the C. glutamicum Pc activity grown on dif ferent carbon sources. Besides, this method was used to assay Pc activity i n C. glutamicum 2262 during a temperature triggered glutamate producing pro cess with biotin excess or limitation. (C) 1999 Elsevier Science B.V. All r ights reserved.