Pseudomonas veronii strain 7–41 degrading medium-chain n-alkanes and polycyclic aromatic hydrocarbons

• Published in: Scientific reports Vol. 12; no. 1; pp. 20527 - 13
• Main Authors: Mullaeva, S. A., Delegan, Ya. A., Streletskii, R. A., Sazonova, O. I., Petrikov, K. V., Ivanova, A. A., Dyatlov, I. A., Shemyakin, I. G., Bogun, A. G., Vetrova, A. A.
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 28.11.2022; Nature Publishing Group; Nature Portfolio
• Subjects: 631/326/252/58; 704/172/169/896; Alkanes; Biodegradation; Biodegradation, Environmental; Crude oil; Genetic analysis; Humanities and Social Sciences; Hydrocarbon-degrading bacteria; Metabolites; multidisciplinary; Naphthalene; Naphthalenes; Operons; Polycyclic Aromatic Hydrocarbons; Pseudomonas veronii; Salicylates; Salicylic acid; Science; Science (multidisciplinary)
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-022-25191-5

Pollution of the environment by crude oil and oil products (represented by various types of compounds, mainly aliphatic, mono- and polyaromatic hydrocarbons) poses a global problem. The strain Pseudomonas veronii 7–41 can grow on medium-chain n -alkanes (C 8 –C 12 ) and polycyclic aromatic hydrocarbons such as naphthalene. We performed a genetic analysis and physiological/biochemical characterization of strain 7–41 cultivated in a mineral medium with decane, naphthalene or a mixture of the hydrocarbons. The genes responsible for the degradation of alkanes and PAHs are on the IncP-7 conjugative plasmid and are organized into the alk and nah operons typical of pseudomonads. A natural plasmid carrying functional operons for the degradation of two different classes of hydrocarbons was first described. In monosubstrate systems, 28.4% and 68.8% of decane and naphthalene, respectively, were biodegraded by the late stationary growth phase. In a bisubstrate system, these parameters were 25.4% and 20.8% by the end of the exponential growth phase. Then the biodegradation stopped, and the bacterial culture started dying due to the accumulation of salicylate (naphthalene-degradation metabolite), which is toxic in high concentrations. The activity of the salicylate oxidation enzymes was below the detection limit. These results indicate that the presence of decane and a high concentration of salicylate lead to impairment of hydrocarbon degradation by the strain.