Metabolic degradation of phenazine-1-carboxylic acid by the strain Sphingomonas sp DP58:: the identification of two metabolites

The biotransformation of phenazine-1-carboxylic acid (PCA) by PCA-degrading strain Sphingomonas sp. DP58 yielded small quantities of metabolites and was demonstrated for the first time. The metabolites were isolated by using preparative high-performance liquid chromatography (HPLC). In addition, these were subsequently characterized by gas chromatography (GC)-mass spectrum (MS) after N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA) derivatization and H-1-nuclear magnetic resonance (NMR). They were identified as 4-hydroxy-1-(2-carboxyphenyl) azacyclobut-2-ene-2-carbonitrile (HPAEC) and 4-hydroxy-1-(2-carboxyphenyl)-2-azetidinecarbonitrile (HPAC). The two metabolites had transformational relationship between each other.