Genetic Structure Change in Harvard Vaccine Strain of Clostridium Tetani for the Period of 1990 to 2010 by Pulsed-Field Gel Electrophoresis


ahmad sakhravi 1 , * , Esmaile Asli 1 , Mohammad-Mehdi Feizabadi 2 , Abdolreza Movahedi 3 , Reza Ranjbar 4 , Hosnieh Ketabi 1 , Behnam Rafiee 5


1 Department of Microbiology, Faculty of Sciences, Islamic Azad University, Karaj Branch, Karaj, Iran

2 Department of Microbiology, Tehran University of Medical Sciences, Tehran, Iran

3 Department of Microbiology, Razi Vaccine & Serum Research Institute, Karaj, Iran

4 Molecular Biology Research Center, Baqiyatallah University of Medical Sciences, Tehran, Iran

5 Master of Microbiology, Razi Vaccine & Serum Research Institute, Karaj, Iran


Zahedan Journal of Research in Medical Sciences: 15 (7); e92919
Published Online: January 07, 2013
Article Type: Research Article
Received: March 04, 2012
Accepted: October 22, 2012




Background: PFGE facilitates the differential migration of large DNA fragments through agarose gel by constantly changing the direction of the electrical field during electrophoresis. Possibility of high difference between strains and repeatability make PFGE one of the strong molecular methods in study of bacterial strains in epidemiology. To identifying and DNA fingerprinting of vaccine strain of Clostridium tetani by PFGE technique. Also, possibility of genotyping profile changes in frequency of vaccine strain of C. tetani during the period of 1990 to 2011.
Materials and Methods: The vaccine strain of C. tetani was provided by Razi Vaccine and
Serum Research Institute in Karaj. The seeds were inoculated into Columbia blood agar
and grownP Pfor 72 h. The cultures were incubated at 35°C in anaerobic conditions. The
PFGE analyses were performed using genomicP PDNA digested with the restriction enzyme
SmaI. The electrophoresisP Panalyses were carried out on a CHEF DR III apparatus (Bio-
Rad) and band patterns obtainedP Pwere then analyzed.
Results: The PFGE profile obtained from vaccine strain during a period of more than two decades revealed no remarkable genetic changes and mutations. This type of analysis provides detailed data useful for surveillance of vaccine strains and isolates as well as for the selection of certain predominant profiles for further investigation.
Conclusion: This study showed no considerable change in chromosomal genome of Harvard, the vaccine strain. It is therefore concluded that the vaccine produced by Razi Institute had evidently no alteration or modification in accordance to PFGE profile analysis during a period of more than two decades.


Clostridium tetani Genomic fingerprinting Epidemiology PFGE

© 2013, Zahedan Journal of Research in Medical Sciences. This is an open-access article distributed under the terms of the Creative Commons Attribution-NonCommercial 4.0 International License ( which permits copy and redistribute the material just in noncommercial usages, provided the original work is properly cited.

 The full text of this article is available on the PDF file.

  • 1. The References of this article are available on the PDF file.