2010 Volume 15 Issue 3-4 Pages 91-95
In aquatic environments, the bacterial decomposition of organoarsenic compounds, such as dimethylarsinic acid ((CH3)2AsO(OH); DMAA), was important for evaluation of the dynamics of each arsenic species. The process of the arsenic cycle has been investigated by many researchers. In study, the PCR-DGGE analytical method was established for investigating the microbial community in Lake Kahokugata. When the volume range from 50 to 1.5 mL of water samples were tested for the DNA extraction, the PCR products of 16S rDNA fragments were efficiently obtained from the 1.5 mL of water samples. When water samples were digested using enzyme with (shaken-sample) or without shaking (static-sample), the more amounts of 16S rDNA fragments were amplified from the shaken-samples. Moreover, the phenol extraction with CTAB treatment more efficiently induced the PCR amplification than that without CTAB treatment. On the acrylamide gels of DGGE analysis, the PCR products of shaken-sample with or without CTAB treatment and static-sample with or without CTAB treatment indicated similar band patterns, suggesting that the DNA extraction treatments used in this study did not influence the detectable bacterial compositions. After DMAA was added at final concentrations of 1 μmol/l to the sample water, the DMAA was remarkably degraded at the 14th day. On the DGGE gel image, a few of bands were specifically detected in the DMAA addition sample at the 14th day. Presumably, the DMAA addition induce the growth of specific bacteria relating to the aquatic DMAA-degradation.
