Quantitative determination of glutamine and glutamic acid

Abstract

L-Glutamine yields 1 molecule each of NH3 and of CO2 when added to washed suspension of Clostridium welchii in acid soln. The formation of NH3 precedes that of CO2. The "glutaminase" of the organism is highly specific; none of many substances tested was found to yield NH3. The sum of the glutamine and glutamic acid in the soln. for analysis is determined manometrically by the CO2 evolved on decarboxylation with C. welchii. NH3 is then estimated with and without treatment with the bacteria. The difference represents the glutamine. The decarboxylation of glutamine is markedly accelerated by cetyl trimethylammonium bromide, serum or tissue extracts. The glutamine and glutamic acid content of animal tissues in-creases after death owing to autolysis.