**'Repeat in ToXin' - named because there are several peptide repeats within the molecules
**'Repeat in ToXin' - named because there are several peptide repeats within the molecules
−
**Produced by various Gram-negative bacteria, including [[Escherichia coli|''E. coli'']]
+
**Produced by various Gram-negative bacteria, including [[Escherichia coli|''E. coli'']], [[Bordetella|''Bordetella sp.'']] and [[''Pasteurella haemolytica#Pasterurella''|''Pasteurella haemolytica'']]
**Possess four contiguous genes, C, A, B and D
**Possess four contiguous genes, C, A, B and D
**A is the structural gene; B and D are required for secretion; C is required for post-translational activation of the gene product of A to produce a functional product
**A is the structural gene; B and D are required for secretion; C is required for post-translational activation of the gene product of A to produce a functional product