Biochemical Studies on Vitamin B12 Part XI

(1) In the present paper, further con-firmation was obtained by repeated in-tensive experiments with Co-porphyrin-derivatives freshly prepared from pure chlorophyll a and b by the column chromatographic method of Gattermann and Wieland. The effect on Euglena(chlorophyll free) was always revealed to be positive. (2) Moreover, vitamin B12.-mass pro-ducing experiments with Co-porphyrin-derivative and 5, 6-dimethylbenzimidazole was attempted by Euglena gracilis strains in B12-Free basal medium, and vitamin B12 was isolated from both cells and broth by paper electrophoresis. The increase of a fair quantity of total vitamin B12 was always seen in the cells and the broth of control strains. (3) Therefore, the authors are inclined to propose the close implication of cobalt-porphyrin-derivative in the biosynthesis of vitamin B12 by Euglena.