FUNCTION OF FLAVOENZYMES IN ELECTRON TRANSPORT 1 67 



27. Ernster, L., Biodiem. Soc. Symp. 16, 54 (1959). 



28. Lindberg, O., Low, H., Conover, T. E., and Ernster, L., this volume p. i. 



29. Martius, C, and Nitz-Litzow, D., Biochim. biophys. Acta 12, 134 (1953). 



30. Brodie, A. ¥.,y. bio/. Chem. 234, 398 (1959). 



31. Anderson, W. \V., and Dallam, R. Y^.,J. biol. CJiem. 234, 409 (1959). 



32. Beyer, R. E.,^. biol. Chem. 234, 688 (1959). 



33. Ernster, L., and Low, H., Exp. Cell Res. Siippl. 3, 133 (1955). 



34. Azzone, G. P., Ernster, L., and Klingenberg, ^L, Xature, Loud. 188, 552 

 (i960). 



35. Slater, E. C, Xature, Loud. 172, 975 (1953). 



36. Chance, B., and Williams, G. R., Advauc. Enzymol. 17, 65 (1956). 



37. Slater, E. C, Rev. Pure appl. Chem. (Australia) 8, 221 (1958). 



38. Low, H., Siekevitz, P., Ernster, L., and Lindberg, O., Biochitu. biophys. Acta 

 29, 392 (1958). 



39. Grabe, B., Biochim. biophys. Acta 30, 360 (1958). 



40. Lindberg, O., Grabe, B., Low, H., Siekevitz, P., and Ernster, L., Acta chem. 

 scaud. 12, 598 (1958). 



41. Walker, P. G., Biochem. J. 58, 699 (1954). 



42. Chance, B., /;/ " Ciba Foundation Symposium on Regulation of Cell Meta- 

 bolism"". J. and A. Churchill Ltd. London, 91 (1959). 



43. Azzone, G. F., Eeg-Olofsson, O., Ernster, L., Luft, R., and Szabolcsi, G., 

 Exp. Cell Res. 22, 415 (1961 ). 



44. Baltscheffsky H., Biochim. biophys. Acta 25, 382 (1957). 



45. Chance, B., and Hagihara, B., Biochem. biophys. Res. Conini. 3, 6 (i960). 



46. Lardy, H. A., Johnson, D., and McMurrav, W. C, Arch. Binchcm. BiopJivs. 

 78, 587 (1958). 



47. Chance, B., Biochem. biopliys. Res. Co?}im. 3, 10 (i960). 



48. Copenha^'er, J. H., and Lardy, H. A.,jf. biol. Chem. 195, 225 (1952). 



49. Pressman, B. C, BiocJiim. biophys. Acta 17, 273 (1955). 



50. Hatefi, Y., Biochitu. biopliys. Acta 31, 502 (1959). 



51. Hunter, F. E., and Hixon, W. S., 7- biol. Cheru. l8l, 67 (1949). 



52. Azzone, G. F., and Ernster, l^.,J. biol. Cheru. 236, 1501 (1961). 



53. .Azzone, G. F., and Ernster, L.,_7. biol. Chem. 236, 1510 (1961). 



Discussion 



Williams: I should like to ask Dr. Ernster why he thinks pyridine nucleotide 

 reduction is necessary in the ATP-activating succinate respiration ? I ask this 

 question for two reasons, first : in his own results respiration in fact seemed to be 

 active at a time when little reduction of pyridine nucleotide had taken place; 

 secondly, because in collaborative experiments with Dr. Chance this summer in 

 Philadelphia, we were also able to reactivate the respiration with ATP while seeing 

 essentially no change in the steady states of the pyridine nucleotides. You didn't 

 speculate on the reason why you needed pyridine nucleotide reduction. 



Ernster: We do not mean that we need pyridine nucleotide reduction. Our 

 point is that the two mechanisms: activation of succinate oxidation and succinate- 

 linked DPX-reduction may be correlateti in the sense that, during the initiation of 

 succinate oxidation, a reduced high-energy intermediate is generated at the level 

 of the respiratory chain, and that this intermediate is identical with, or in close 

 relationship to, the high-energy intermediate involved in the first respiratory 



