Bacterial oxidation of dipicolinic acid. II. Identification of alpha-ketoglutaric acid and 3-hydroxydipicolinic acid and some properties of cell-free extracts.

Kobayashi, Yasuo (University of Tokyo, Tokyo, Japan) and Kei Arima. Bacterial oxidation of dipicolinic acid. II. Identification of alpha-ketoglutaric acid and 3-hydroxydipicolinic acid and some properties of cell-free extracts. J. Bacteriol. 84:765-771. 1962-When a dipicolinic acid (DPA)-decomposing bacterium, Achromobacter strain 1-2, was incubated at 30 C with shaking in a DPA solution containing 10(-3)m arsenite, a keto acid was accumulated. The 2,4-dinitrophenylhydrazone of this acid was synthesized and identified as alpha-ketoglutaric acid by paper chromatography, visible absorption spectrum, infrared analysis, elemental analysis, and mixed melting point. During this incubation, oxalic acid equivalent to the consumed dipicolinic acid was produced. A fluorescent material was also isolated from culture fluid and identified as 3-hydroxydipicolinic acid by paper chromatography and the ultraviolet absorption spectrum. Further, cell-free extracts were prepared by sonic oscillation. Ferrous ion and a reduced di- or triphosphopyridine nucleotide-generating system were proven to be required for enzymic oxidation of DPA. And 3-hydroxydipicolinic acid was also oxidized by this preparation. From the results obtained, a possible metabolic pathway of dipicolinic acid was proposed.