title: Mycoplasma orale has a sequence similar to the insertion-like sequence of M. fermentans.
abstract: Polymerase chain reaction (PCR) using the Mycoplasma fermentans insertion sequence-like element (ISLE) RW primer set amplifies DNA from Mycoplasma orale when more than 1 ng is present in the reaction tube. In this study, amplified products from 11 different clinical isolates and the ATCC prototype of M. orale were sequenced and compared to 206 bp amplicons from eight isolates and the ATCC strain of M. fermentans. The nucleotide sequences of the amplified M. orale products had high sequence homology (88-92%) to those from M. fermentans, but differed at several key positions. The M. orale products contained a DraI restriction enzyme site not found in any of the M. fermentans amplified products. Consistent with this finding, the PCR products from M. orale were digested by DraI while the PCR products from M. fermentans were resistant to DraI digestion. The results suggest that M. orale may carry a similar IS-like element that complicates but does not negate using the ISLE PCR assay designed to detect M. fermentans. It appears possible for the RW primers to amplify M. orale if the mycoplasmas are present at higher concentrations. The amplified products can be differentiated from those from M. fermentans by a rapid DraI restriction endonuclease digestion or by Southern blot analysis using the RW006 internal probe under highly stringent conditions.
authors.affiliation: Department of Infectious and Parasitic Diseases Pathology, American Registry of Pathology, Washington, DC 20306, USA.
authors.forename: S E
authors.initials: SE
authors.lastname: Ditty
authors.forename: M A
authors.initials: MA
authors.lastname: Connolly
authors.forename: B J
authors.initials: BJ
authors.lastname: Li
authors.forename: S C
authors.initials: SC
authors.lastname: Lo
mesh_terms: D001483:Base Sequence; D004269:DNA, Bacterial / Q000032:analysis; D006801:Humans; D008969:Molecular Sequence Data; D009174:Mycoplasma / Q000235:genetics*; D016858:Mycoplasma fermentans / Q000235:genetics*; D012689:Sequence Homology, Nucleic Acid
chemical_list: D004269:DNA, Bacterial