AMPLIFICATION AND RESTRICTION-ENDONUCLEASE DIGESTION OF A LARGE FRAGMENT OF GENES-CODING FOR RIBOSOMAL-RNA AS A RAPID METHOD FOR DISCRIMINATION OF CLOSELY-RELATED PATHOGENIC BACTERIA

By use of primers specific to conserved regions of the rRNA gene clust er, a discrete amplicon of approximately 5 kb was amplified by PCR fro m all 21 bacterial genera investigated. Subsequent endonuclease digest ion of the PCR product with HaeIII distinguished between the three spe cies of the human pathogen Francisella spp. on the one hand and four c linically relevant genomic groups of Acinetobacter spp. on the other h and. The described technique has the potential as a rapid method for d iscriminating between closely related species that are of clinical imp ortance.