David H. Brown
1957
Citations
0
Influential Citations
10
Citations
Journal
Methods in Enzymology
Abstract
Publisher Summary D(+)-Glucosamine has been shown to be rapidly phosphorylated by ATP in the presence of crystalline yeast hexokinase to give D-glucosamine-6-phosphate. The phosphate ester can be isolated from an enzymatic incubation mixture by precipitating it as the ethanol-insoluble barium salt and purifying it by reprecipitation. In the procedure nucleotides are removed by mercury precipitation. Glucosamine-6-phosphate may be determined by making use of its reduction of reagent 60 of Shaffer and Somogyi and subsequently employing the arsenomolybdate reagent of Nelson for color development. Glucosamine hydrochloride should be used as a standard. For analysis of 0.05 micromole or less of glucosamine-6-phosphate, the ferricyanide oxidation method of Park and Johnson may be used, but the only suitable standard is a pure solution of the ester itself, because it reduces much less than does glucosamine on a molar basis. Neutral salts have a marked effect on this method.