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Vibrio cholerae illness is driven almost entirely by its secreted cholera (exo)toxin; the lipopolysaccharide endotoxin it carries plays little or no role in the natural pathogenesis of cholera. In contrast, endotoxin is a key virulence factor in sepsis caused by Klebsiella or E. coli, and Mycobacterium is not Gram-negative at all [Nair, 2010, PMID 20428396; Vanden Broeck, 2007, PMID 17716938].