Some Observations on the Characteristics and Distribution of Adenosine Triphosphatases in Young Roots of Pisum sativum, Cultivar Alaska

A study has been made of some characteristics of ATPases fromyoung pea roots and these enzymes have been shown to differfrom ß glycerophosphatases in several respects. DEAEchromotography and gel electrophoresis have confirmed the existenceof a number of different phosphatases with differing affinitiesfor ATP and sodium ß glycerophosphate. At least twoATP-specific phosphatases have been detected and these accountfor about 57 per cent of the total ATPase activity in pea roots. The distribution of ATPase activity along the axis of the roothas been determined by biochemical assay of serial sectionsand by histochemical methods. It is shown that ATPase activityhas a quite different distribution from ß glycero-phosphataseactivity, thus confirming the separate identity of the two enzymesystems. The distribution of ATPases is discussed in relation to theirpossible role in ion transport.