The rifampin resistant Alcaligenes faecalis strain A1501R survived at a high, initially stable and later slowly declining population size (10 8 to 10 6 CFU per g dry soil) for 60 days in microcosm experiments. Intr...The rifampin resistant Alcaligenes faecalis strain A1501R survived at a high, initially stable and later slowly declining population size (10 8 to 10 6 CFU per g dry soil) for 60 days in microcosm experiments. Introduction of strain A1501R did not cause great changes in the community profiles generated via microbial community level 16S rDNA based PCR followed by denaturing gradient gel electrophoresis (DGGE) and the Biolog substrate utilization system. The introduction of A1501R had no impact on the dominant bacterial populations in soil. Significant differences in the utilization of some substrates were observed between the control and inoculated soils using a combination of DGGE and Biolog analysis. Results of DGGE and BIOLOG analysis show that introduction of A1501R can affect the lactic acid utilizing bacterial community in case of selection by lactic acid. A specific probe based on the 16S rDNA variable region V6 was constructed via PCR amplification of 16S rDNA using the 971(f) and 1057(r) primers for the detection of A. faecalis strains introduced into soils. Dot blot hybridization of strains or soil DNA and aligment of sequences of the V6 region of 16S rDNA from different bacterial strains show that the V6 probe is very specific for A. faecalis A1501R.展开更多
文摘The rifampin resistant Alcaligenes faecalis strain A1501R survived at a high, initially stable and later slowly declining population size (10 8 to 10 6 CFU per g dry soil) for 60 days in microcosm experiments. Introduction of strain A1501R did not cause great changes in the community profiles generated via microbial community level 16S rDNA based PCR followed by denaturing gradient gel electrophoresis (DGGE) and the Biolog substrate utilization system. The introduction of A1501R had no impact on the dominant bacterial populations in soil. Significant differences in the utilization of some substrates were observed between the control and inoculated soils using a combination of DGGE and Biolog analysis. Results of DGGE and BIOLOG analysis show that introduction of A1501R can affect the lactic acid utilizing bacterial community in case of selection by lactic acid. A specific probe based on the 16S rDNA variable region V6 was constructed via PCR amplification of 16S rDNA using the 971(f) and 1057(r) primers for the detection of A. faecalis strains introduced into soils. Dot blot hybridization of strains or soil DNA and aligment of sequences of the V6 region of 16S rDNA from different bacterial strains show that the V6 probe is very specific for A. faecalis A1501R.
