<i>C. botulinum</i> strains analyzed in this study, and genomic location of their <i>bont</i>/B and /A PCR-RFLP subtype genes.

1CDC (Centers for Disease Control and Prevention, USA); ISS (Istituto Superiore di Sanità, Italy). 2IB (infant botulism); FB (foodborne botulism); AB (animal botulism); uB (unknown botulism). 3Bnp (non-proteolytic B); Bbv (bivalent B). 4The size of the closest molecular standard bands are indicated. 5Non-proteolytic C. botulinum. 6n.d. = Not determined, because of DNA degradation.