title: Decolorization of malachite green and crystal violet by waterborne pathogenic mycobacteria.
abstract: Mycobacterium avium, Mycobacterium intracellulare, Mycobacterium scrofulaceum, Mycobacterium marinum, and Mycobacterium chelonae tolerate high concentrations of the dyes malachite green and crystal violet. Cells of strains of those species decolorized (reduced) both malachite green and crystal violet. Because decolorized malachite green lacked antimicrobial activity, the resistance of these mycobacteria could be due, in part, to their ability to decolorize the dyes. Small amounts of malachite green and its reduced, decolorized product were detected in the lipid fraction of M. avium strain A5 cells grown in the presence of malachite green, suggesting that a minor component of resistance could be due to sequestering the dyes in the extensive mycobacterial cell surface lipid. The membrane fraction of M. avium strain A5 had at least a fivefold-higher specific decolorization rate than did the crude extract, suggesting that the decolorization activity is membrane associated. The malachite green-decolorizing activity of the membrane fraction of M. avium strain A5 was abolished by either boiling or proteinase exposure, suggesting that the decolorizing activity was due to a protein. Decolorization activity of membrane fractions was stimulated by ferrous ion and inhibited by dinitrophenol and metyrapone.
authors.affiliation: Department of Biology, Virginia Union University, Richmond, Virginia 23220, USA.
authors.forename: Jefferson J
authors.initials: JJ
authors.lastname: Jones
authors.forename: Joseph O
authors.initials: JO
authors.lastname: Falkinham
mesh_terms: D000891:Anti-Infective Agents, Local / Q000494:pharmacology*; D024881:Drug Resistance, Bacterial; D005840:Gentian Violet / Q000494:pharmacology*; D009162:Mycobacterium avium / Q000187:drug effects*; D015269:Mycobacterium avium Complex / Q000187:drug effects; D019907:Mycobacterium fortuitum / Q000187:drug effects; D019910:Mycobacterium marinum / Q000187:drug effects; D015359:Mycobacterium scrofulaceum / Q000187:drug effects; D012394:Rosaniline Dyes / Q000494:pharmacology*; D014871:Water Microbiology
chemical_list: D000891:Anti-Infective Agents, Local; D012394:Rosaniline Dyes; C005095:malachite green; D005840:Gentian Violet