Cclvii. the Role of Fumarate in the Respiration of Bacterium Coli Commune by Hans

SZENT-GYORGYI and his co-workers [1935; 1936] and Stare & Baumann [1936] have recently shown that certain simple organic molecules such as fumarate, oxaloacetate and pyruvate take part as catalysts in cellular respiration. The function of these catalysts in respiration can be conveniently formulated as transport of hydrogen and for our present purpose they will therefore be termed "hydrogen carriers". An attempt is made in this paper to analyse the role of this type of hydrogen carriers in the respiration of Bact. coli commune. The experiments aimed at elucidating the following points: 1. Which substances act as hydrogen carriers in the cell? 2. The rate of hydrogen transport by a given carrier. 3. The nature of the chemical grouping donating hydrogen to the carrier. 4. The nature of the chemical grouping accepting hydrogen from the carrier. 5. The significance of a given carrier in cellular respiration. These five points will be referred to later as the "programme" of this paper. Only in some special cases was it possible to find the answer to all five questions. In other cases the analysis had to remain incomplete owing to the experimental difficulties which arise from the complex and involved nature of the chemical organization of the cell.