In the current study, we evaluate the relationships of Pseudomonas spp. strains with specific biomarkers of exposure to polycyclic aromatic hydrocarbons (PAHs) in wild Chirostoma jordani Woolman, 1894 and assess the capacity of these bacteria to biotransform PAHs. Intestinal Pseudomonas – degrading of hydrocarbons isolated from Chirostoma jordani

In the current study, we evaluate the relationships of Pseudomonas spp. strains with specific biomarkers of exposure to polycyclic aromatic hydrocarbons (PAHs) in wild Chirostoma jordani Woolman, 1894 and assess the capacity of these bacteria to biotransform PAHs. Molecular identification and phylogenetic analysis showed four strains obtained from 750 colonies. The activity of the naphthalene dioxygenase system of the bacteria exposed to 0.1, 1.0 and 10 µg/L of PAHs was higher than the mean isoform 1A1 (CYP1A1) activity of the fish, particularly in PM4 strains like Pseudomonas aeruginosa and in a PM1 strain related with Pseudomonas fluorescens. However, the epoxide hydrolase activity of the strains was lower in all cases compared with the fish. Glutathione S-transferase (GST) activity of the bacterial strains was lower than in the liver but higher than in viscera. Using redundancy analysis two differentiating patterns were found. Independent of seasons and lakes, CYP1A1 activity of fish was induced by naphthalene and anthracene water levels. The PM4 strain biotransformation of endogenous levels of benzo[a]pyrene, benzo[k]fluoranthene and indeno[1,2,3-cd]pyrene allowed the hydroxylated metabolites to conjugate with glutathione by GST activity of the fish. In this way, renal excretion in C. jordani was possible, contributing to fish protection.