A rapid molecular taxonomy technique on the bacteria genus and species by 16S rDNA and 16S-23S rDNA intergenic spacer regions sequences

Objective To explore a rapid method for classification of microorganisms.Methods The electrophorese fingerprinting, direct sequence of 16S rDNA and 16S-23S rDNA ISR after PCR, multiplex PCR for 16S rDNA and antibiotic resistance genes, were utilized to explore fast approaches of extracting total DNA from different clinical specimens.Results The specific 16S-23S rDNA ISR fingerprinting fragments were shown on the genus or species level in bacteria and fungi.So fingerprinting can be used to identify pathogenic microorganisms, to differentiate the evolution relations or to set the phylogenetic tree by comparing their DNA banding patterns with those of standard strains (NCCLS). Multiplex PCR was able to examine the special genes of genus or species, mecA gene, TEM, SHV and CTX gene in staphylococcus and ESBLs(E.coli or K.pneumoniae) at the same time.Conclusion The part of 16S rDNA sequencing and 16S-23S rDNA ISR genotypes by gel electrophoreses were useful for bacterial species identification in addition, it was clearly more rapid and accurate than culture technique, and the large numbers of strains can easily be examined.Multiplex PCR could provide a good method for identification of microorganisms and analysis of antibiotic resistance at the same time.