PHYLOGENETIC ANALYSIS OF FUSOBACTERIUM-PRAUSNITZII BASED UPON THE 16SRIBOSOMAL-RNA GENE SEQUENCE AND PCR CONFIRMATION

In order to develop a PCR method to detect Fusobacterium prausnitzii i n human feces and to clarify the phylogenetic position of this species , its 16S rRNA gene sequence was determined. The sequence described in this paper is different from the 16S rRNA gene sequence of F. prausni tzii in the GenBank database (accession number M58682). A PCR assay ba sed on the new sequence is specific for F. prausnitzii, and the result s of this assay confirmed that F. prausnitzii is the most common speci es in human feces, However, a PCR assay based on the original GenBank sequence was negative when it was performed with two strains of F. pra usnitzii obtained from the American Type Culture Collection. A phyloge netic tree based on the new 16S rRNA gene sequence was constructed, On this tree F. prausnitzii was not a member of the Fusobacterium group but was closer to some Eubacterium spp, and located between Clostridiu m ''clusters III and IV'' (M. D. Collins, P. A. Lawson, A. Willems, J. J. Cordoba, J. Fernandez-Grayzabal, P. Garcia, J. Cai, H. Hippe, and J. A. E. Farrow, Int. J. Syst. Bacteriol. 44:812-826, 1994).