title: Thermonuclease gene as a target for specific identification of Staphylococcus intermedius isolates: use of a PCR-DNA enzyme immunoassay.
abstract: A PCR-DNA enzyme immunoassay (PCR-DEIA) was developed for identification of the coagulase-positive species Staphylococcus intermedius. Two PCR primers and a hybridization probe were designed to target specific sequences of the S. intermedius thermonuclease (nuc) gene. In addition to S. intermedius reference strains, the PCR-DEIA was tested using 295 veterinary and human S. intermedius isolates. A specific 933-bp DNA fragment was successfully amplified in 281 (94.9%) S. intermedius isolates. Five canine isolates showed an unexpected 2.8-kbp band. Except for 10 amplicons derived from equine, camel, and pigeon isolates, all positive PCR results (n = 288, 96.6%) were confirmed by the colorimetric microtiter plate DEIA hybridization. Isolates that failed both in amplification and DEIA hybridization were only observed in equine isolates (10/23, 43.5%). Except for the limitations with isolates of hoofed animals, the S. intermediusnuc PCR assay has potential for rapid identification of S. intermedius and differentiation from other coagulase-positive staphylococci including S. aureus.
authors.affiliation: Institute of Medical Microbiology, University of Münster Hospital, 48149 Münster, Germany. kbecker@uni-muenster.de
authors.forename: Karsten
authors.initials: K
authors.lastname: Becker
authors.forename: Christof
authors.initials: C
authors.lastname: von Eiff
authors.forename: Birgit
authors.initials: B
authors.lastname: Keller
authors.forename: Michaela
authors.initials: M
authors.lastname: Brück
authors.forename: Jerome
authors.initials: J
authors.lastname: Etienne
authors.forename: Georg
authors.initials: G
authors.lastname: Peters
mesh_terms: D000818:Animals; D015373:Bacterial Typing Techniques; D017931:DNA Primers; D004285:Dogs; D006801:Humans; D007124:Immunoenzyme Techniques / Q000379:methods; D008836:Micrococcal Nuclease / Q000235:genetics* / Q000378:metabolism; D016133:Polymerase Chain Reaction / Q000379:methods*; D012680:Sensitivity and Specificity; D013045:Species Specificity; D013210:Staphylococcus / Q000145:classification* / Q000201:enzymology / Q000235:genetics
chemical_list: D017931:DNA Primers; D008836:Micrococcal Nuclease