FUNCTION 



medium and on hydrolysis biotin was liberated, supporting the growth 

 of 5. cerevisiae 139, which does not respond to the coenzyme. 



Oxidation of Pyruvic and Lactic Acids 



A suggestion by Summerson et al}"^ that biotin may be concerned 

 with the oxidation of pyruvic acid and lactic acid indicates yet 

 another possible function of biotin. The evidence for the suggestion 

 was that carbon dioxide production was markedly increased when 

 biotin was added to liver slices from biotin-deficient rats respiring in 

 a solution containing lactate or pyruvate as substrate. These results 

 are supported by similar observations made by Olson et al.'^^ on the 

 respiration of ventricle slices from biotin-deficient ducks. In presence 

 of succinate the oxygen uptake was much less than normal and the ac- 

 cumulation of lactic acid decreased. In addition the production of C^^ 

 carbon dioxide from labelled succinate by ventricle slices was much less 

 with tissue from biotin-deficient ducks than with tissue from controls. 



References to Section 18 



1. D. R. Miller, J. O. Lampen and W. H. Peterson, /. Amer. Chem. 



Soc, 1943, 65, 2369. 



2. D. Burk and R. J. Winzler, Science, 1943, 97, 57. 



3. S. A. Koser, M. H, Wright and A. Dorfman, Proc. Soc. Exp, Biol. 



Med., 1942, 51, 204. 



4. J. L. Stokes, A. Larsen and M. Gunness, /. Bad., 1947, 54, 19, 



219 ; /. Biol. Chem., 1947, 167, 613. 



5. H. C. Lichstein and W. W. Umbreit, ibid., 1947, 170, 329. 



6. H. A. Lardy, R. L. Potter and C. A. Elvehjem, ibid., 1947. 169, 451. 



7. W. Shive and L. L. Rogers, ibid., 453. 



ya. A. E. Axelrod, S. E. Purvis and K. Hofmann, ibid., 1948, 176, 695. 



8. S. Ochoa, A. Mehler, M. L. Blanchard. T. H. Jukes, C. E. Hoffmann 



and M. A. Regan, ibid., 1947, 170, 413. 



9. H. A. Lardy, R. L. Potter and R. H. Burris, /. Biol. Chem., 1949, 



179, 721 ; P. R. MacLeod and H. A. Lardy, ibid., 733 ; P. R. 

 MacLeod, S. Grisolia, P. P. Cohen and H. A. Lardy, ibid., 19 A9, 



180, 1003. 



10. D. B. Melville, J. G. Pierce and C. W. H. Partridge, ibid., 299. 



11. H. C. Lichstein andW. W. Umbreit, ibid., 1947, 170, 423. 



12. H. C. Lichstein and J. F. Christman, ibid., 1948, 175, 649. 



13. A. E. Axelrod, K. Hofmann, S. E. Purvis and M. Mayhall, ibid., 991. 



14. H. C. Lichstein, ibid., 1949, 177, 487. 



15. H. C. Lichstein, ibid., 125. 



16. H. C. Lichstein and J. F. Christman, /. Bact., 1949, 58, 565. 



17. W. H. Summerson, J. M. Lee and C. W. H. Partridge, Science, 



1944, 100, 250. 

 i8. R. E. Olson, O. N. Miller, Y. J. Topper and F. J. Stare, /. Biol. 

 Chem., 1948, 175, 503. 



445 



