2-NAPHTHOATE CATABOLIC PATHWAY IN BURKHOLDERIA STRAIN JT-1500

A Burkholderia strain (JT 1500), able to use 2-naphthoate as the sole source of carbon, was isolated from soil. On the basis of growth chara cteristics, oxygen uptake experiments, enzyme assays, and detection of intermediates, a degradation pathway of 2-naphthoate is proposed. The features of this pathway are convergent with those for phenanthrene. We propose a pathway for the conversion of 2-naphthoate to 1 mol (each ) of pyruvate, succinate, and acetyl coenzyme A and 2 mol of CO2. Duri ng growth in the presence of 2-naphthoate, six metabolites were detect ed by thin-layer chromatography, high-performance liquid chromatograph y, and spectroscopy, 1-Hydroxy-2-naphthoate accumulated in the culture broth during growth on 2-naphthoate. Also, the formation of 2'-carbox ybenzalpyruvate, phthalaldehydate, phthalate, protocatechuate, and bet a-carboxy-cis,cis-muconic acid was demonstrated. (LR,2S)-cis-1,2-Dihyd ro-1,2-dihydroxy-2-naphthoate was thus considered an intermediate betw een 2-naphthoate and 1-hydroxy-2-naphthoate, but it was not transforme d by whole cells or their extracts. We conclude that this diol is not responsible for the formation of 1-hydroxy-2-naphthoate from 2-naphtho ate but that one of the other three diastereomers is not eliminated as a potential intermediate fora dehydration reaction.