Labelled trinucleotides as quantitative probes to identify Bacillus spp. using fluorescent probes to identify in situ hybridization

The number of nucleotide tripler repeats in 16S rRNA sequences can be used for detection and identification of bacteria. Labelled TTT, GGG and ATA tri plets were hybridized to the ribonucleic acid of Bacillus subtilis and Baci llus fusiformis whole-cells and the number of such triplets was quantified by synchronous fluorescence spectrometry. Each species was distinctly ident ified by specific ratios of labelled TTT, GGG and ATA triplets as well as c haracteristic fluorescence spectra. Notwithstanding the absence of intrinse c specificity, fluorescein-conjugated nucleotide triplet probes appear to b e a useful tool for fluorescent spectrometric identification of micro-organ isms through the quantitation of trinucleotide repeats. (C) 2000 Academic P ress.