The effect of surface-active agents on bacterial glutamic decarboxylase and glutaminase

Abstract

An acceleration of the decarboxylation of glutamate by extracts and intact cells of Clostridium welchii, previously reported for Cetavlon, was given by homologous n-alkyltrimethylammonium bromides. The minimum number of C atoms in the alkyl sub-stituent needed to give the effect was 10 for both intact cells and extracts. The number of C atoms causing maximum acceleration was 16 in the case of cells and 16-18 in the case of extracts. A parallelism was observed between the ability of cationic detergents to form micelles in aqueous soln., and their ability to accelerate the decarboxylation of glutamate and glutamine. Max. acceleration of the decarboxylase within the homologous series approx. coincided with the "critical point of micelle formation" as detd. by the color change of indicators. Anionic surface-active agents inhibited the decarboxylation of glutamate and glutamine. Nonionic surface-active agents and fatty acids were without effect.