In cell free extract fromNeisseria meningitidisan enzyme has been found which catalyses the oxidation of L‐malate to oxaloacetate in the absence of pyridine nucleotides, using ferricyanide as electron acceptor. The enzyme was found to be particle‐bound, as determined by sucrose gradient centrifugation. Activity corresponding to this enzyme was demonstrated in extracts from all strains tested of selectedNeisseriaspecies. In contrast to the large differences in NAD‐linked malate dehydrogenase activity among the species, the interspecies variation of the pyridine nucleotide independent oxidation of malate was not sufficiently distinct to be useful for classification pur