Survival of naphthalene-degrading Pseudomonas putida NCIB 9816-4 in naphthalene-amended soils: toxicity of naphthalene and its metabolites

• Published in: Applied microbiology and biotechnology Vol. 64; no. 3; pp. 429 - 435
• Main Authors: Park, W, Jeon, C.O, Cadillo, H, DeRito, C, Madsen, E.L
• Format: Journal Article
• Language: English
• Published: Berlin Springer 01-04-2004; Springer Nature B.V
• Subjects: Accumulation; Aerobic conditions; Bacteria; biodegradation; Biodegradation, Environmental; Biological and medical sciences; bioremediation; Biotechnology; Catechols - analysis; Chromatography; Chromatography, High Pressure Liquid; Colony Count, Microbial; Crystals; Fundamental and applied biological sciences. Psychology; Gas chromatography; Gas Chromatography-Mass Spectrometry; Liquid chromatography; Mass spectrometry; Metabolites; Microbiology; Naphthalene; Naphthalenes - analysis; Naphthalenes - metabolism; Naphthalenes - toxicity; Pigments, Biological - analysis; pollutants; polluted soils; Pseudomonas putida; Pseudomonas putida - drug effects; Pseudomonas putida - metabolism; Soil amendment; Soil Microbiology; Toxicity; Pseudomonadales; Degradation; Soils; Naphthalene; Metabolite; Toxicity; Bacteria; Pseudomonadaceae; Pseudomonas putida; Survival
• ISSN: 0175-7598; 1432-0614
• DOI: 10.1007/s00253-003-1420-6

Survival of naphthalene-degrading Pseudomonas putida NCIB 9816-4 was measured in nonsterile soil samples (coal tar-contaminated and pristine) with and without added crystalline naphthalene over a period of 21 days. A 2-3 log decrease in cfu occurred in the presence, but not absence, of added naphthalene. We used aqueous suspensions of crystalline naphthalene to explore potential mechanisms of its toxicity on the test bacterium under aerobic conditions. Measurements of dissolved naphthalene in medium indicated that uptake by P. putida NCIB 9816-4 maintained naphthalene at concentrations well below saturation. Accumulation of catechol was documented by high-performance liquid chromatography and gas chromatography/mass spectrometry in the presence of 0.5% (w/v) naphthalene crystals. Transient catechol accumulation was highest when cells entered stationary phase. A decrease in catechol concentration correlated with the development of brown color in the medium. Brown pigment accumulation correlated with a decrease in viable cell counts. These results suggested that catechol, related compounds, and their condensation products can accumulate to toxic levels in stationary phase P. putida NCIB 9816-4 cells. We hypothesize that the same mechanism of toxicity may occur under the nutrient-limited conditions expected in soil.