TAXON SPECIFIC HYBRIDIZATION PROBES FOR FIBER-DIGESTING BACTERIA SUGGEST NOVEL GUT-ASSOCIATED FIBROBACTER

Six oligonucleotide probes complementary to the 16S rRNAs of members o f the genus Fibrobacter were designed for identification at the levels of genus, species and subspecies. The temperature of dissociation (T- d) of probe-target hybrid was determined for each probe and used to co ntrol the stringency of hybridization. Specificity was demonstrated by comparing hybridization to rRNA from target and nontarget species imm obilized on nylon membranes. Hybridization to nucleic acid isolated fr om cable and goat gut contents suggested greater genetic diversity amo ng this assemblage of fiber-digesting bacteria than now represented in pure culture.