Biodefluorination and biotransformation of fluorotelomer alcohols by two alkane‐degrading Pseudomonas strains

Fluorotelomer alcohols [FTOHs, F(CF 2 ) n CH 2 CH 2 OH, n  = 4, 6, and 8] are emerging environmental contaminants. Biotransformation of FTOHs by mixed bacterial cultures has been reported; however, little is known about the microorganisms responsible for the biotransformation. Here we reported biotransformation of FTOHs by two well‐studied Pseudomonas strains: Pseudomonas butanovora (butane oxidizer) and Pseudomonas oleovorans (octane oxidizer). Both strains could defluorinate 4:2, 6:2, and 8:2 FTOHs, with a higher degree of defluorination for 4:2 FTOH. According to the identified metabolites, P. oleovorans transformed FTOHs via two pathways I and II. The pathway I led to the production of x :2 ketone [dominant metabolite, F(CF 2 ) x C(O)CH 3 ; x  =  n  − 1, n  = 6 or 8], x :2 sFTOH [F(CF 2 ) x CH(OH)CH 3 ], and perfluorinated carboxylic acids (PFCAs, perfluorohexanoic, or perfluorooctanoic acid). The pathway II resulted in the formation of x :3 polyfluorinated acid [F(CF 2 ) x CH 2 CH 2 COOH] and relatively minor shorter‐chain PFCAs (perfluorobutyric or perfluorohexanoic acid). Conversely, P. butanovora transformed FTOHs by using the pathway I, leading to the production of x :2 ketone, x :2 sFTOH, and PFCAs. This is the first study to show that individual bacterium can bio‐transform FTOHs via different or preferred transformation pathways to remove multiple CF 2 groups from FTOHs to form shorter‐chain PFCAs. Biotechnol. Bioeng. 2012; 109: 3041–3048. © 2012 Wiley Periodicals, Inc.