[A method of determining glucose-6-phosphate dehydrogenase in bacteria of the genus Yersinia]

A method for qualitative assessment of glucose-6-phosphate dehydrogenase in Yersinia is suggested. The reaction mixture was prepared by mixing the ingredients in the ratios as follows: 10 microliters of 0.01 M glucose-6-phosphate, 10 microliters of 0.0075 M NADP, 30 microliters of 0.75 M tris HCl pH 7.8, 10 microliters of 0.2 M MgCl2, 20 microliters of distilled water. The reaction was triggered by adding 20 microliters of cell-free bacterial extract. After 110-130 min incubation 10-20 microliters aliquots w re collected on filter paper (Whatman No 1) strips. The stains were dried at ambient temperature and examined in UV light at 365 nm with the use of a routine UV lamp. This method shows intensive fluorescence of the stain in M. tuberculosis and very poor fluorescence in Y. pestis. This technique is convenient when the scope of identification tests and differentiation between these two agents is high.