Phylogenetic Analysis of Nocardia spp. using 16S rRNA, hsp65 and gyrB Genes

Nocardia is one of the most important aerobic actinomycetes that lives in soil and can enter the human body by inhalation and traumatic inoculation and causes Nocardiosis. Molecular methods are one of the best methods for rapid and accurate identification and differentiation of species of this group of bacteria. The purpose of this study was evaluation of three housekeeping genes in identification and differentiation of most important species of Nocardia.
In this study cross-sectional, first, gene sequences of 16S rRNA, gyrB and hsp65 for ten species of Nocardia were obtained from Genebank (NCBI). Then, those sequences were transferred to MEGA 5.0. Finally, phylogenetic trees based on each of 16S rRNA, gyrB and hsp65 genes were drawn.
Phylogenetic trees analysis based on 16S rRNA, gyrB and hsp65 gene sequences indicated that all of these genes could identify and differentiate Nocardia species. Also, it was found that gyrB gene is the best option for drawing the phylogenetic relationships of Nocardia species.
According to this research, for accurate identification of Nocardia species, several housekeeping genes should be investigated simultaneously.