Rapid species identification of coagulase negative Staphylococci by rRNA spacer length polymorphism analysis.
OBJECTIVE
The identification of coagulase-negative staphylococci (CNS) is carried out mainly through conventional methods, commercial identification kits, and molecular biology-based methods. We evaluated the efficiency of PCR analysis of tRNA intergenic spacer length polymorphism (tDNA-ILP) and 16S-23S intergenic spacer length polymorphism (16S-23S ILP), and also that of restriction analysis of 16S-23S intergenic spacer amplification products (RA 16S-23S), for the rapid and accurate identification of CNS species.


METHODS
The PCR assays of rRNA spacer length polymorphisms were tested with nine reference type strains and 122 clinical isolates. The results were compared with those obtained by conventional methods and the Vitek system for clinical isolates.


RESULTS
Seventy-eight (63.9%) of 122 strains were identified as the same species with conventional identification, the Vitek GPI system, tDNA-ILP, and RA 16S-23S. The 16S-23S ILP analysis did not produce distinguishable PCR fragments. The results of tDNA-ILP analysis were in agreement with those of RA 16S-23S to the species level for 98.2% except for unknown patterns (eight isolates).


CONCLUSIONS
These results indicate that tDNA-ILP and RA 16S-23S analysis are potentially valuable tools for rapid and accurate CNS identification.
Lee
M K
MK
Department of Clinical Pathology, Chung-Ang University College of Medicine, Chung-Gu, Seoul, South Korea.
Park
A J
AJ
D003030:Coagulase / Q000096:biosynthesis; D021903:DNA, Ribosomal Spacer / Q000235:genetics*; D005069:Evaluation Studies as Topic; D066298:In Vitro Techniques; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D012335:RNA, Ribosomal / Q000235:genetics*; D012343:RNA, Transfer / Q000235:genetics*; D013203:Staphylococcal Infections / Q000175:diagnosis; D013210:Staphylococcus / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification
D003030:Coagulase; D021903:DNA, Ribosomal Spacer; D012335:RNA, Ribosomal; D012343:RNA, Transfer