E. L. R. Stokstad

Effect of Selenium in Preventing Exudative Diathesis in Chicks

Summary (1) Chicks fed a diet containing torula yeast developed exudative diathesis which could be prevented by either vit. E or a non-fat soluble substance in casein and in a number of pork tissues. (2) This factor could be made water soluble by acid hydrolysis. It was adsorbed on both anion and cation exchange resins and thus behaved as an ampholyte. (3) An alkaline ash but not an acid ash of pork kidney was effective in preventing exudative diathesis. (4) Selenium as selenite prevented exudative diathesis at 0.3 ppm. Tellurium as tellurite was ineffective at 3 ppm. Anionic arsenic at 10 ppm was inactive.

Further Observations on the “Animal Protein Factor”

Summary and Addendum 1. Fermentation products of Streptomyces aureofaciens were found to promote growth in depleted chicks on various diets which were adequately supplied with vitamin B12. 2. Growth responses in chicks on a corn-soybean diet were also produced by crystalline aureomycin hydrochloride and by cultures in which the aureomycin, as measured by antibiotic potency, was destroyed by alkaline hydrolysis. 3. Responses were also obtained with succinylsulfathiazole, streptomycin and 3-nitro-4-hydroxyphenylarsonic acid, but these substances appeared less potent than aureomycin. No responses were obtained with dried whey or dried brewers yeast. Following the submission of this manuscript, Dr. Paul Gyorgy kindly showed us a manuscript (Gyorgy, P., Stokes, J., Jr., Smith, W. H., and Goldblatt, H., Transactions of Conference on Biological Antioxidants, sponsored by the Macy Foundation, November, 1949) which described a beneficial exerted by aureomycin on growth and the prevention of dietary hepatic necrosis in rats. The assumption was made that aureomycin might act through the suppression of the intestinal flora. The assistance of Vincent Stryeski, Alfred Plattner and Joseph Lang in the care of the animals is gratefully acknowledged.

Assay of Anti-Pernicious Anemia Factor with Euglena.:

Summary The algal flagellate Euglena gracilis var. bacillaris was shown to exhibit a quantitative growth response to crystalline antipernicious anemia factor, using a chemically defined medium. Thymidine was inactive.

Observations on the Effect of 4-Amino-Pteroylglutamic Acid on Mice

Summary The 4-amino analogue of pteroylglutamic acid was fed to mice as a dietary supplement. There was some indication of reversal by pteroylglutamic acid of the effect on mice when the level of the antagonist was 0.3 part per million of diet. Death was found to occur within a few days with levels of 1 part per million of diet or higher. The effect was not reversed by feeding high levels of pteroylglutamic acid. This finding may be contrasted with the inhibitory effect of the 4-amino compound on S. jecalis R which is reversed by pteroylglutamic acid.

Acceleration of Pteroylglutamic Acid Deficiency in Mice and Chicks by a Chemical Antagonist

Summary Mice on a purified diet with added succinylsulfathiazole developed no signs of pteroylglutamic acid deficiency within 6 weeks. When a crude synthetic preparation of a pteroylglutamic acid antagonist was added to the diet a syndrome appeared which was characterized by slow growth, anemia and leucopenia. Pteroylglutamic acid prevented the appearance of the syndrome. The development of pteroylglutamic acid deficiency in chicks on a purified diet was aggravated by adding the antagonist to the diet, and the effects of the antagonist were reversed by pteroylglutamic acid.

Vitamin B12b Some Properties and its Therapeutic Use.

Summary A pink fraction obtained from liver and from Streptomyces aureofaciens has been separated from vitamin B12 by silicic acid chromatography and has been shown to have different ultraviolet and visible absorption spectra. This new substance, vitamin B12b, has been prepared in crystalline form and has been found to be effective parenterally in the treatment of patients with Addisonian pernicious anemia in amounts of 1 to 2 μg daily. We are indebted to Mrs. Helen Jakubowski for performing the blood examination.

Effect of Various Levels of Vitamin B12 Upon Growth Response Produced by Aureomycin in Chicks

Summary 1. The vit. B12 requirement for growth of chicks was studied on a deficient diet with and without the addition of aureomycin. In some experiments, a “sparing effect” of aureomycin upon vit. B12 requirement was noted but in others no effect was observed. A growth-promoting effect for aureomycin was noted both in the presence and absence of added vit. B12. 2. The mortality of deficient chicks on the diet containing no added vit. B12 was markedly reduced by aureomycin. 3. The addition of sulfamethazine to the diet did not appear to effect the quantitative requirement of chicks for vit. B12.

Heparin-like anticoagulants from Mollusca.

Summary Heparin-like polysaccharides with high anticoagulant activity have been isolated from 2 species of clams, Mactra spissula and Artica islandica. These purified polysaccharides, termed mactin-A and mac-tin-B, are related to but not identical with mammalian heparin. They possess a greater in vivo activity and a favorable therapeutic index when compared with heparin preparations of equal in vitro activity.

Some Observations on Growth Factors Required by Leuconostoc citrovorum.

Summary 1. Leaconostoc citrovorum was found to respond to a growth-promoting factor in the concentrated liver extract, but this organism did not respond to vitamin B12. The alkali-stable nature of the “citrovorum factor” further contrasts it with vitamin B12. 2. Two fractions were separated from liver extract by paper strip chromatography; one of these fractions was presumably thymidine and promoted growth of Lactobacillus leichmannii and Leuconostoc citrovorum. The other fraction was inactive for L. leichmannii but active for L. citrovorum. 3. Although thymidine or high levels of pteroylglutamic acid (PGA) when tested singly were only partially effective in promoting growth of L. citrovorum, the simultaneous addition of thymidine plus PGA produced marked growth of the organism. This finding suggests a functional relationship between thymidine, PGA and the “citrovorum factor.”

Role of Protogen in the Nutrition of an Unidentified Corynebacterium

Summary An unidentified gram-positive bacillus has been found which requires protogen for growth in about one-fiftieth of the concentration required by Tetrahymena geleii.