Table 1. Shiga toxin variants and disease progression.

Toxin	Amino acid homology† (%)	Disease progression‡
Stx1	–	D → HC → HUS
Stx1c	(A) 97; (B) 95	D → HC → HUS
Stx1d	(A) 93; (B) 92	D
Stx2	–	D → HC → HUS
Stx2c	(A) 100; (B) 97	D → HC → HUS
Stx2c2	(A) 100; (B) 97	D
Stx2d	(A) 99; (B) 97	D
Stx2dactivatable	(A) 99; (B) 97	D → HC → HUS
Stx2e	(A) 93; (B) 84	D
Stx2f	(A) 63; (B) 57	D

^†% amino acid sequence homology of (A) A-subunits and (B) B-subunits of Stx1 variants vs Stx1 or Stx2 variants vs Stx2. Data derived from [140–145].

^‡Adapted from [22].

D: Diarrhea; HC: Hemorrhagic colitis; HUS: Hemolytic uremic syndrome; Stx: Shiga toxin.