Accession Number : ADA327021

Title :   Nonrecombinant Genetic Modification of Aquifer Bacteria to Achieve Constitutive Degradation of Trichloroethylene.

Descriptive Note : Final rept. Jun 94-Aug 95,

Corporate Author : UNIVERSITY OF WEST FLORIDA PENSACOLA DEPT OF BIOLOGY

Personal Author(s) : Shields, Malcolm S.

PDF Url : ADA327021

Report Date : DEC 1996

Pagination or Media Count : 116

Abstract : Aquifer bacteria were isolated for their capacity to predominate following nutrient enrichment (field application vectors (FAVs)), and screened as hosts for the Tn5 containing, constitutive toluene ortho-monoxygenase (Tom) expressing plasmid: TOM(31c) (which causes the cooxidation of trichloroethylene (TcE)). Tom expression during positive selection in native aquifer sediments contaminated with TCE was determined. Three such FAVs were constructed: NFG-2 (TOM3ic), MFI-l (TOM3ic), and MFG-2 (TOM3ic). All stably maintained TOM3ic and constitutively degraded TCE. Like the original TOM31c mutant strain (Burkholderia cepacia G4 PR131), MFG-2 (TOM31c) was unable to significantly degrade TCE in native sediments despite inoculation to high levels (>/- 1 x 10(8) cells/gram), and did not apparently survive well in glucose amended material. NFG-2 (TOM3ic) and MFI-l (TOM3ic) did significantly degrade TCE in glucose and IGEPAL (respectively) amended aquifer sediments. Like PRl31 (TOM31c), Tn5 gene probes indicated that these FAVs also remained above 10(6) cells per cm(3) of sediment during a 20 day feeding and TCE degradation experiment. TOM31c was transferable to these selectable FAVs by non-recombinant mating techniques, and once there encoded constitutive TCE degradation in native sediments untreated save for the addition of a specific carbon and energy sources.

Descriptors :   *BACTERIA, *RECOMBINATION REACTIONS, *GENETICS, *TRICHLOROETHYLENE, SOURCES, DEGRADATION, MODIFICATION, ENERGY, CARBON, NUTRIENTS, PLASMIDS, AQUIFERS, INOCULATION, SEDIMENTS, GLUCOSE.

Subject Categories : Biochemistry
      Microbiology

Distribution Statement : APPROVED FOR PUBLIC RELEASE