Vitamin B1 and cocarboxylase in animal tissues

Abstract

THE discovery by Lohmann & Schuster [1937] that cocarboxylase is the pyrophosphoric ester of vitamin B1 suggested that in animal tissues the vitamin is active like this ester in the oxidation of pyruvic acid. It now seems clear that animal tissues and certain bacteria do not decarboxylate pyruvic acid to acetaldehyde and CO2 (as yeast does) but instead oxidize it to acetic acid and C02, either by dismutation under anaerobic conditions or directly [Krebs & Johnson, 1937; Lipmann, 1937, 1; Weil-Malherbe, 1937]. Lipmann [1937, 2] reports that with acetone preparations from B. Delbruickii the simultaneous decarboxylation and oxidation of pyruvic acid require cocarboxylase.In animal tissues evidence that vitamin B1 pyrophosphate is concerned in the oxidation of pyruvic acid is derived (1) from catatorulin tests, and (2) from the presence of cocarboxylase in tissues and their alleged capacity to synthesize cocarboxylase from vitamin B1. The first point, that cocarboxylase can replace vitamin B1 in catatorulin tests [Lohmann & Schuster, 1937], has not been confirmed in this laboratory using "teased" brain [Peters, 1937]; more recent unpublished experiments with brain slices also gave negative results. This point obviously requires further elucidation.In regard to the second point, Auhagen [1932] first showed that boiled extracts of animal tissues stimulated the decarboxylation of pyruvic acid by yeast preparations (aetiozymase), indicating the presence of cocarboxylase. Simola [1932] investigated the influence of nutrition upon this phenomenon. Synthesis of cocarboxylase from vitamin B1 by minced animal tissues or various tissue preparations has been reported from several laboratories [von Euler & Vestin, Hofer [1937] reported negative results. This work is not yet sufficiently quantitative and further it has not so far been ascertained whether vitamin B1 is present in tissues in the free form.We have now developed a method which allows the separate quantitative estimation of cocarboxylase and free vitamin B1, by means of which the following points have been investigated: (1) the cocarboxylase and vitamin B1 contents of boiled extracts from normal and avitaminous tissues, (2) the enzymic synthesis of cocarboxylase from vitamin B1. In the present paper we shall show that there is much more cocarboxylase than vitamin B1 present in animal tissues, and that it is much reduced when vitamin B1 is withheld from the diet, and further, that the liver readily synthesizes cocarboxylase from vitamin B1 in vivo. Another paper will deal with the synthesis of cocarboxylase in vitro. Various organs (brain, muscle) have only a very limited power of synthesis ;2 intestinal mucosa does not show any activity at all, whereas active preparations can be obtained from the liver. 1 A preliminary report of this work appeared in the Tran8. Soc. Chem. Ind. 57, 470, 1938. 2 Less in the case of brain than suggested by Peters [1937], who did not know of the stimulating effect of vitamin B1 upon the action of cocarboxylase (cf. below).( 1501 )

Thiamine and Cocarboxylase Concentration in Heart, Liver, and Kidney, of Patients with Heart Failure

“…The results are in agreement with experimental data reported by several investigators that dietary restriction of thiamine results in a decrease of tissue concentration of both thiamine and cocarboxylase (8,9). We and others have suggested that patients with heart failure are apt to show thiamine deficiency because of inadequate intake of thiamine in the food, poor absorption of ingested thiamine, and also as a result of the use of mercurials for elimination of edema (2,3,10).…”

Heterotrophic Assimilation of Carbon Dioxide

“…If such were not the case, addition of cocarboxylase would not increase the rate of pyruvate oxidation by the muscle. Ochoa and Peters (64) have shown that there is a marked difference in the vitamin content of the different organs of an animal showing effects of vitamin deficiency, and that liver usually has a lower content of the vitamin than the muscle. The observed difference in the effect of the vitamin on addition to muscle and liver may not have resulted from a stimulation of a reaction present in liver and absent in muscle but, instead, because the liver was deficient in cocarboxylase and the muscle was not.…”

Vitamins B1, B2, B6, Niacin, and Ascorbic Acid

“…The procedure described by Ochoa and Peters (51) has been revised exten sively (52,53), and may be applied to blood and to a variety of other tissues. The principle involves the effectiveness of the test substance in restoring the activity of a solution of excess purified apodecarboxylase.…”