Genotyping Clostridium botulinum toxinotype A isolates from patients using amplified rDNA restriction analysis

1 Pasteur Institute of Iran, Department of Bacteriology, Pasteur Avenue, Tehran, Iran 2 Logman Hospital, Department of Infectious Diseases, Tehran, Iran 3 Institut Pasteur, Unité des Anaérobies, 25–28 Rue du Dr Roux, F-75724, Paris Cedex 15, France Correspondence M. Pourshafie pour{at}pasteur.ac.ir Received April 27, 2005 Accepted June 27, 2005 In this study, the application of amplified rDNA restriction analysis (ARDRA) for characterizing Clostridium botulinum toxinotype A strains isolated from individuals with botulism was evaluated. Ten restriction enzymes were tested for their suitability in ARDRA as a typing method and Hha I was selected for the best outcome. Analysis of Hha I restriction profiles of the amplified products divided C. botulinum isolates into three clusters. Non-toxigenic Clostridium sporogenes strains showed an ARDRA restriction pattern that was distinct from those observed for C. botulinum . The successful use of ARDRA for subdivision of C. botulinum in this study confirmed that this technique is a powerful method for typing of C. botulinum toxinotype A clonal diversity. In addition, it is rapid, sensitive and simple. Abbreviations: ARDRA, amplified rDNA restriction analysis; RAPD, randomly amplified polymorphic DNA.