Comparison of randomly cloned and whole genomic DNA probes for the detection of Porphyromonas gingivalis and Bacteroides forsythus.
Whole genomic and randomly-cloned DNA probes for two fastidious periodontal pathogens, Porphyromonas gingivalis and Bacteroides forsythus were labeled with digoxigenin and detected by a colorimetric method. The specificity and sensitivity of the whole genomic and cloned probes were compared. The cloned probes were highly specific compared to the whole genomic probes. A significant degree of cross-reactivity with Bacteroides species, Capnocytophaga sp. and Prevotella sp. was observed with the whole genomic probes. The cloned probes were less sensitive than the whole genomic probes and required at least 10(6) target cells or a minimum of 10 ng of target DNA to be detected during hybridization. Although a ten-fold increase in sensitivity was obtained with the whole genomic probes, cross-hybridization to closely related species limits their reliability in identifying target bacteria in subgingival plaque samples.
Wong
M
M
Department of Periodontics, School of Dental Medicine, University of Pennsylvania, Philadelphia 19104-6002, USA.
DiRienzo
J M
JM
Lai
C H
CH
Listgarten
M A
MA
D015373:Bacterial Typing Techniques; D001439:Bacteroides / Q000235:genetics / Q000302:isolation & purification*; D002167:Campylobacter / Q000235:genetics; D003001:Cloning, Molecular; D003124:Colorimetry; D015342:DNA Probes; D004269:DNA, Bacterial / Q000235:genetics; D003773:Dental Plaque / Q000382:microbiology*; D004076:Digoxigenin; D016680:Genome, Bacterial; D009693:Nucleic Acid Hybridization; D016966:Porphyromonas gingivalis / Q000235:genetics / Q000302:isolation & purification*; D018720:Prevotella / Q000235:genetics; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013045:Species Specificity
D015342:DNA Probes; D004269:DNA, Bacterial; D004076:Digoxigenin