Trout intestinal alkaline phosphatases I. Some physical‐chemical characteristics

Four electrophoretic zones of trout intestinal alkaline phosphatase are described on the basis of charge and molecular weight heterogeneity. Qualitative and quantitative differences in the intestinal phosphatase complement suggest three basic phenotypes, which are exemplified by the isozyme patterns of wild brook trout, hatchery brook trout, and lake trout. The partially purified and separated trout phosphatase zones have been characterized physically and chemically. The data presented clearly place these enzymes in the category of the non‐specific alkaline phosphomonoesterases. In common with this group of enzymes, trout phosphatases catalyze the hydrolysis of a wide variety of phosphomonoesters and pyrophosphates, as well as transphosphorylation reactions.