Presence and distribution of a 3'-nucleotidase in bean seedlings
De Greef, J.A.; Moereels, E.; Verbelen, J.P.
Archives Internationales de Physiologie et de Biochimie 84(3): 596-597
1976
ISSN/ISBN: 0003-9799 PMID: 64176 Document Number: 110032
The activity of an ATPase system in Phaseolus vulgaris seedlings at pH 7.2 in the presence of Na, K and Mg ions was modulated by red light illumination. Histochemical and cytochemical techniques showed that in the hook region of the stem the enzyme complex was located at the plasmalemma level of the hypodermal cells. With Na and K ions there was another ATPase opt. at pH 8.2; screening for substrate specificity revealed in AMPase with pronounced specificity for 3'-AMP. A high 3'-AMP hydrolase activity was found in primary leaves and also in the stem in which the apex contained 10 times more activity than the stem base (fresh wt. basis). In the epicotyl hook the 3'-AMP hydrolase activity was mainly confined to the hypodermal collenchyma cells.