Studies on the Mechanism of Hydrogen Transport in Animal Tissues I. Triose Phosphate Oxidation in the Presence of Malonate* by v. R. Potter?

According to the Szent-Gyorgyi theory’ (2-6) the oxidation of intermediary metabolites in animal tissues takes place through the alternate reduction and oxidation of certain 4-carbon dicarboxylic acids which function catalytically as hydrogen carriers and transport the hydrogen of metabolites to the cytochrome system. The metabolite specifically mentioned is triose phosphate ((2) p. 28) and the 4-carbon acids are oxalacetic, malic, fumaric, and succinic. According to the theory, the oxidation of triose phosphate should be represented by the following equations, which may or may not represent direct reactions.