Figure 11

Dendrogram of the ntnh gene in different BoNT-producing strains. The dendrogram of 3,471 nucleotides of the ntnh gene shows the variation within this gene. Some of the ntnh sequence variation in the strains is due to recombination events. The location of the ntnh in ATCC 3502, ATCC 19397 and Hall strain close to the ntnh within the serotype B strains resulted from a recombination event midway within the ntnh gene resulting in a recombinant B/A ntnh, that is a partial B ntnh and partial A ntnh. Another similar recombination event in ntnh of the 7I03-H strain has resulted in a recombinant C/A ntnh, that is a partial C ntnh and a partial A ntnh. The Langeland F ntnh location in the dendrogram near the serotype A strains of Kyoto-F, Loch Maree and 657 resulted from a recombination event near the 3' end or following the ntnh gene where a bont/f was inserted. The dendrogram illustrates the variation in the ntnh genes from multiple serotypes and the location of recombinant ntnh genes.