Production of metabolites from chlorobiphenyls by resting cells of Pseudomonas strain LB400 after growth on different carbon sources

摘要

Cells of Pseudomonas strain LB400, grown on biphenyl, glucose, or glycerol, transformed polychlorinated biphenyl (PCB) congeners into chlorobenzoic acid (CBA) metabolites. Transformation of the PCB congeners, 2,3 chlorobiphenyl (CBP), 2,2'-CBP, 2,5,4'-CBP, and 2,4,2',4'-CBP, produced the metabolites, 2,3-CBA, 2-CBA, and 4-CBA, and 2.4-CBA, respectively. Rates and extents of PCB transformation and metabolite formation were highest with biphenyl-grown cells. Intermediate rates of metabolite production were observed with glycerol-grown cells, and lowest rates of production were found with glucose-grown cells. Regardless of carbon source, the rate of degradation of congeners was faster than the rate of production of CBAs. Relative rates of PCB transformation and metabolite production from different congeners with cells grown on a particular substrate followed the same general order, 2,3-CBA (from 2,3-CBP) >2-CBA (from 2,2'-CBP)>4-CBA(from 2,5,4'-CBP)>2,4-CBA (from 2,4,2',4'-CBP). Pseudomonas strain LB400 appeared unable to grow on any of the chlorobenzoic acids. However, Pseudomonas strain LB400 cells grown on biphenyl appeared capable of degrading 2-CBA and 2,3-CBA but not 4-CBA nor 2,4-CBA. Cells grown on glycerol appeared unable to metabolize and CBAs.