Open Access Kent State (OAKS)

Three approaches for concentrating stream bacterioplankton were compared for analysis by in situ hybridization: centrifugation; filtration onto a polymer membrane and transfer to a gel-coated slide; and filtration onto an inorganic filter disk. Stream bacterioplankton were hybridized with a species-specific oligonucleotide probe targeted for 23S rRNA of Burkholderia cepacia for analysis of variability among techniques. The inorganic filter technique yielded three to six times higher total cell counts and appeared to be effected less by interfering suspended particles and differences in site conditions than the other two concentration methods. Hybridization of samples with minimum cell loss yielded different, and presumably more accurate, estimates of the relative abundance of B. cepacia than the other methods.