Involvement of linear plasmids in aerobic biodegradation of vinyl chloride.
Pseudomonas putida strain AJ and Ochrobactrum strain TD were isolated from hazardous waste sites based on their ability to use vinyl chloride (VC) as the sole source of carbon and energy under aerobic conditions. Strains AJ and TD also use ethene and ethylene oxide as growth substrates. Strain AJ contained a linear megaplasmid (approximately 260 kb) when grown on VC or ethene, but it contained no circular plasmids. While strain AJ was growing on ethylene oxide, it was observed to contain a 100-kb linear plasmid, and its ability to use VC as a substrate was retained. The linear plasmids in strain AJ were cured, and the ability of strain AJ to consume VC, ethene, and ethylene oxide was lost following growth on a rich substrate (Luria-Bertani broth) through at least three transfers. Strain TD contained three linear plasmids, ranging in size from approximately 90 kb to 320 kb, when growing on VC or ethene. As with strain AJ, the linear plasmids in strain TD were cured following growth on Luria-Bertani broth and its ability to consume VC and ethene was lost. Further analysis of these linear plasmids may help reveal the pathway for VC biodegradation in strains AJ and TD and explain why this process occurs at many but not all sites where groundwater is contaminated with chloroethenes. Metabolism of VC and ethene by strains AJ and TD is initiated by an alkene monooxygenase. Their yields during growth on VC (0.15 to 0.20 mg of total suspended solids per mg of VC) are similar to the yields reported for other isolates (i.e., Mycobacterium sp., Nocardioides sp., and Pseudomonas sp.).
Department of Environmental Engineering & Science, Box 340919, Clemson University, Clemson, SC 29634-0919, USA.
Anthony S
AS
Danko
Meizhong
M
Luo
Christopher E
CE
Bagwell
Robin L
RL
Brigmon
David L
DL
Freedman
D000332:Aerobiosis; D001673:Biodegradation, Environmental; D005027:Ethylene Oxide / Q000378:metabolism; D005030:Ethylenes / Q000378:metabolism; D006256:Hazardous Waste; D008969:Molecular Sequence Data; D042041:Ochrobactrum / Q000235:genetics* / Q000254:growth & development / Q000302:isolation & purification / Q000378:metabolism*; D010105:Oxygenases / Q000235:genetics / Q000378:metabolism; D010957:Plasmids / Q000235:genetics*; D016958:Pseudomonas putida / Q000235:genetics* / Q000254:growth & development / Q000302:isolation & purification / Q000378:metabolism*; D014752:Vinyl Chloride / Q000378:metabolism*
D005030:Ethylenes; D006256:Hazardous Waste; C036216:ethylene; D010105:Oxygenases; C072883:alkene monooxygenase; D005027:Ethylene Oxide; D014752:Vinyl Chloride