Design and uses of Bdellovibrio 16S rRNA-targeted oligonucleotides

An 18-mer oligonucleotide almost exclusively targeting Bdellovibrio spp. was designed based on available 16S rRNA sequence data. The specificity of this oligonucleotide used as a PCR primer in combination with a Bacteria domain-targeted primer as well as used as a probe in rRNA dot blot hybridizations was experimentally confirmed using a variety of alpha-, beta-, gamma-, delta-Proteobacteria and Gram-positive bacteria. Similarly, combinations of the Bacteria primer with oligonucleotides targeting the 16S rRNA gene of Bdellovibrio bacteriovorus and Bdellovibrio stolpii were shown to be species specific by PCR. Positive amplification products were obtained from an irrigation water sample in which a low level of bdellovibrios was detected by plating as well as from soil detached from potato tubers, using the Bdellovibrio spp.-Bacteria and the B. bacteriovorus-Bacteria primer pairs.