The Question of the Synthesis of Thiamin by the Ciliate, Glaucoma Piriformis

Thiamine and Tetrahymena

“…We are in agreement with Hall and Cosgrove (1944) regarding the mineral requirements of Tetrahymena and accordingly the inorganic salts were always added. We do not know the specific effect of riboflavin on strain W but knowing that this vitamin is rapidly destroyed in alkaline solution by light it was thought best to add sufficient amounts to insure against its being a limiting factor.…”

“…It seems evident that the denial by Hall and Cosgrove (1944) of our previous conclusions (that T. geleii can synthesize thiamine) can now be dismissed. There can be no question of the thiamine-free nature of our medium.…”

“…To all of the media used in the following experiments were added just before sterilization the following inorganic salts (Hall and Cosgrove, 1944): 0.02 per cent MgSO4,7H20; 0.02 per cent K2HPO4; 0.01 per cent CaCl2 2H2O; 0.00025 per cent FeCl2 6H2O; 0.00001 per cent MnCl2 4H2O; 0.00001 per cent ZnCl2. To all media was also added 0.1 microgram per ml.…”

Biochemical Factors in the Maximal Growth of Tetrahymena

“…(Hall, 1942;Hall and Cosgrove, 1944 and data presented here), supplementary factors and an organic source of nitrogen which supplies the needs for both carbon and nitrogen. The requirement for a source of carbon separate from the source of nitrogen has never been demonstrated.…”

Studies on the Biochemistry of Tetrahymena. Vii. Riboflavin, Pantothen, Biotin, Niacin and Pyridoxine in the Growth of T. Geleii W

“…When proteins, such as casein or gelatin, or peptones are used as the base medium it has been impossible to determine the importance of those vitamins which were stable to treatments which would not also destroy other essential materials. Using these types of media, claims have been made for the essential nature of thiamine and of riboflavin for Teirahyuiena geleii (Hall and Cosgrove, 1944;Hall, 1944). It was earlier indicated (Kidder and Dewey, 1942) and later conclusively proven (Kidder and Dewey, 1944;1945a;1945b) that at least eight strains of Tetrahymena could grow in a medium in which the thiamine had been destroyed.…”