Die Methylierung durch pflanzliche und tierische Gewebe. 7. Mitteilung. Zum Mechanismus der Methylübertragung des Cholins

Some Investigations on Choline Metabolism in Aspergillus Niger

“…For the transfer of the methylgroup to ethanolamine two reactionmechanisms have been described [BARRENSCHEEN (5) and CANTONI (29)]; regarding the formation of the watersoluble bound choline no data are known.…”

“…COHEN and his collaborators (36) observed a degradation of choline to trimethylamine, ethanolamine, ammonia and ethyleneglycol in some species of Clostridium. During their investigations on the creatine-synthesis with minced muscle of caviae BARRENSCHEEN and PANTLISCHKO (5) came to the conclusion that besides the oxidation of choline to betaine another way exists whereby choline is degradated; the end-product in this case would be trimethylaminoxide.…”

“…Later on the amount of total choline decreases. 2,5 ;g E' .2 E' 2,0 Qj u E' 1,5 . As during the impoverishment the quantity of dry material of the mycelium decreases much more than the amount of choline it is probable that this group of compounds is not easily taken up in the metabolism.…”

“…The results of such an experiment * are mentioned in fig. 4 where the quantity of choline and betaine present in the mycelium and in the nutritive solution were determined after 2 1 / 2 , 5,7,10,12 and 14 days. The quantity ofcholine and betaine present in the nutrition solution was again very small.…”

“…According to BARRENSCHEEN C.S. (5) this transfer would only take place after the oxidation of methionine to methionine-sulfoxide.…”