Zur Biochemie und Physiologie von Galegin in Galega officinalis L.

Abstract

During the development (8 days) of young Galega officinalis plants only 0,9 mg of arginine H·HCl, but 7 mg of total-galegine· 1/2 H 2 SO 4 and 125mg of asparagine/100 plants were synthesized. Quantitative estimations and studies using 14 C-galegine have shown that galegine is not a nitrogen storage compound in Galega officinalis . In the spring the increase of galegine in the shoots of rapidly growing young plants paralleled the increase of the dry weight. Also, during, the development of flowers and fruits significant changes in thp galpgine content were observed. After 3 days only 3 % of biosynthetically produced 14 C-galegine fet to young Galega officinalis plants was degraded; however, after 11 days 25 % was degraded. Grafting studies, experiments with artificially rooted leaves, sterile culture of isolated roots and biosynthesis of galegine in seedlings growing with roots and without roots in 14 CO 2 have shown that galegine and hydroxygalegine are not synthesized in the roots but in the shoots of the young plants. Further studies with 14 CO 2 have shown that biosynthesis takes place in growing leaves and especially in fruits during their development. Unripe seeds which are able to assimilate and also to synthesize galegine Can obtain additional assimilates from the fruit coats. Part of the gaiegine accumulated in the seeds can be synthesized in the fruit coats and leaves. Basal and apical translocation of 14 C-galegine is possible in the presence and absence of the root system. Galegine is fixed by the plant cells in the immediate vicinity of the vessels. Studies with 14 C-labelled precursors demonstrated that the amidine group of galegine is derived from arginine, apparently by a transamidination reaction. Herrn Prof. Dr. K. M othes bin ich für die stete Förderung meiner Arbeit zu großem Dank verpflichtet. Für die technische Unterstützung bei der Durchführung der Versuche danke ich Fräulein CH. S chimpf .