title: DNA extraction from nocardia species for special genes analysis using PCR.
abstract: BACKGROUND
  Nocardia species have a complex cell wall structure similar to that of mycobacteria, and the extraction of DNA from this bacterium is extremely difficult. Currently, to identify Nocardia species particularly, it is essential to utilize molecular techniques.
  
  
  OBJECTIVE
  In the present study, we investigated STET (sodium chloride-TRIS-EDTA-triton) buffer for the extraction of high-quality genomic DNA from 20 clinical and environmental isolates.
  
  
  METHODS
  The extracted DNA was evaluated for portion of the 16S rRNA, 65-kDa heat-shock protein and 16S rRNA genes via polymerase chain reaction.
  
  
  RESULTS
  The extracted DNA had high molecular mass, and its concentration and purity was suitable when tested in 1% agarose gel, and using UV spectrophotometry. Amplification of three different genes was successfully performed.
  
  
  CONCLUSIONS
  This paper reveals an inexpensive, reproducible and efficient method of DNA extraction from Nocardia species, which is appropriate for accurate identification of this bacterium via polymerase chain reaction and polymerase chain reaction-restriction fragment length polymorphism.
authors.affiliation: Department of Pathobiology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Mehdi Fatahi
authors.initials: MF
authors.lastname: Bafghi
authors.affiliation: Department of Pathobiology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Seyyed Saeed
authors.initials: SS
authors.lastname: Eshraghi
authors.affiliation: Department of Bacteriology and Virology, Alborz University of Medical Sciences, Karaj, Iran.
authors.forename: Parvin
authors.initials: P
authors.lastname: Heidarieh
authors.affiliation: Department of Pathobiology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Shadi
authors.initials: S
authors.lastname: Habibnia
authors.affiliation: Department of Pathobiology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Masoumeh Rasouli
authors.initials: MR
authors.lastname: Nasab
keywords: 16S rRNA; DNA extraction; Nocardia; PCR; hsp65