Conversion of Salicylate to Catechol by Mycobacterium Fortuitum

It was reported in a previous paper that most strains of Mycobacterium fortuitum blackened a modified Sauton medium agar containing 0.1% (w/v) sodium salicylate. The mechanism of this blackening has been investigated. When a modified Sauton medium containing 0.1% salicylate was inoculated with any of three strains of M. fortuitum, the medium became black after incubation for four days at 37°. The brownish black formazan was isolated by paper chromatography and compared with formazans from the same medium containing 0.1% (w/v) catechol inoculated with the test organisms or without inoculation. These formazans showed similar RF values in three solvent systems and the same absorption spectra (maximum absorption at below 220 and 275 mμ). It has been shown that M. fortuitum is capable of converting salicylate to catechol and that the formazan in the medium is an oxidation product of catechol.