FIG. 1.

Arrangement of the IBCA94-0216 botulism neurotoxin gene cluster. The IBCA94-0216 partial bont/B sequence begins at what would be base pair position 1362 in the intact type B neurotoxin gene, and it continues downstream for an additional 2,514 bp to the 3′ end of the neurotoxin gene. The missing 5′ 1,361 bp of the bont/B gene (which would code for the neurotoxin light chain), as well as any second cluster of accessory genes, could not be found by extensive PCR testing. The prime symbol designates a partial gene.