Oligonucleotide probes for the detection of representatives of the genus Thermoanaerobacter

Based on the analysis of 16S rRNA nucleotide sequences, oligonucleotide probes were designed for the detection of representatives of the genus Thermoanaerobacter. To increase the specificity of detection, the genus Thermoanaerobacter was divided into three groups. The probe Tab 827 (5′-GCTTCCGCDYCCCACACCTA-3′) detected all known representatives of the genus Thermoanaerobacter, the probe Tab_1 844 (5′- TTAACTACGGCACGRAATGCTTC-3′) was specific for the first group of species of the genus (T. wiegelii, T. siderophilus, T. sulfurophilus, T. brockii, T. kivui, T. ethanolicus, T. acetoethylicus, and T. thermohydrosulfuricus); the probe Tab_2 424 (5′-CACTAMYGGGGTTTACAACC-3′) targeted the second group (T. thermocopriae, T. mathranii, and T. italicus); and the probe Tab_3 184 (5′-TCCTCCATCAGGATGCCCTA-3′) was specific for the third group (T. tengcongensis, T. yonseiensis, T. subterraneus, and Carboxydibrachium pacificum, an organism related to the genus Thermoanaerobacter according to its 16S rRNA sequence). The oligonucleotide probes were labeled with Dig-11-dUTP. Hybridization with the probes showed the affiliation with Thermoanaerobacter of several pure cultures that were morphologically similar to representatives of this genus but possessed metabolic features unusual for it (capacity for agarose hydrolysis, anaerobic oxidation of CO, growth at low pH values) or were isolated from habitats previously unknown for Thermoanaerobacter (deep-sea hydrothermal vents).