Application and evaluation of the interlaboratory reproducibility of tRNA intergenic length polymorphism analysis (tDNA-PCR) for identification of Streptococcus species

The discriminatory power, speed, and interlaboratory reproducibility of tRN A intergenic length polymorphism analysis (tDNA-PCR) combined with capillar y electrophoresis was evaluated for the identification of streptococci, Thi s method was carried out in three different laboratories under highly stand ardized conditions for 54 strains belonging to 18 different species. It was concluded that interlaboratory reproducibility of tDNA fingerprints produc ed by means of capillary electrophoresis was sufficiently high to permit th e exchange between different laboratories and the construction of common li braries which can be consulted for comparison with fingerprints obtained in dependently in separate laboratories, In a second step, 17 other species we re included in the study and examined in one of the participating laborator ies. All Streptococcus species studied, except S, mitis, S, oralis, S, para sanguinis, S, pneumoniae, S, thermophilus, and S, vestibularis, showed dist inguishable tDNA fingerprints. A database of well-characterized strains was constructed to enable computer-aided identification of unknown streptococc al isolates.