부산대학교 도서관

Alcaligenes sp. JMP228 carrying 2,4-dichlorophenoxyacetic acid (2,4-D) degradative plasmid pJP4was inoculated into natural soil, and transfer of the plasmidpJP4 to indigenous soil bacteria was investigated with andwithout 2,4-D amendment. Plasmid pJP4 transfer was enhancedin the soils treated with 2,4-D, compared to the soils notamended with 2,4-D. Several different transconjugants wereisolated from the soils treated with 2,4-D, while no indigenoustransconjugants were obtained from the unamended soils.Inoculation of the soils with both the donor Alcaligenessp. JMP228/pJP4 and a recipient Burkholderia cepaciaDBO1 produced less diverse transconjugants than the soilsinoculated with the donor alone. Repetitive extragenicpalindromic-polymerase chain reaction (REP-PCR) analysisof the transconjugants exhibited seven distinct genomic DNAfingerprints. Analysis of 16S rDNA sequences indicatedthat the transconjugants were related to members of thegenera Burkholderia and Pandoraea. Denaturing gradient gelelectrophoresis (DGGE) analysis of PCR-amplified 16S rRNAgenes revealed that inoculation of the donor caused clearchanges in the bacterial community structure of the 2,4-Damendedsoils. The new 16S rRNA gene bands in the DGGEprofile corresponded with the 16S rRNA genes of 2,4-Ddegradingtransconjugants isolated from the soil. The resultsindicate that introduction of the 2,4-D degradative plasmid asAlcaligenes sp. JMP228/pJP4 has a substantial impact on thebacterial community structure in the 2,4-D-amended soil.