Development of strain-specific PCR primers for the identification of Fusobacterium nucleatum subsp. fusiforme ATCC 51190T and subsp. vincentii ATCC 49256T

The objective of this study was to develop the strain-specific PCR primers for Fusobacterium nucleatum subsp. fusiforme ATCC 51190T and F. nucleatum subsp. vincentii ATCC 49256T based on the nucleotide sequence of the Fs17 and Fv35 DNA probes, respectively. The strain specificity was tested against 10 type strains of Fusobacterium spp. or subsp., 21 clinical isolates of F. nucleatum from Koreans, and five type strains of distinct Fusobacterium species. Primer sensitivity was determined by testing serial dilutions (4 ng–4 fg) of the purified genomic DNA from each of the type strains. PCR showed that two pairs of PCR primers, Fs17-F14/Fs17-R14 and Fv35-F1/Fv35-R1 primers, could produce strain-specific amplicons from F. nucleatum subsp. fusiforme ATCC 51190T and F. nucleatum subsp. vincentii ATCC 49256T, respectively. The two PCR primer sets could detect as little as 0.4 pg or 4 pg of the genomic DNA of each target strain. These results suggest that the two sets of PCR primers could be used to identify F. nucleatum subsp. fusiforme ATCC 51190T and F. nucleatum subsp. vincentii ATCC 49256T, particularly for ascertaining the authenticity of the strain.