<prompt> Which of the following is not an AB 5 toxin-Cholera toxinPertussis toxinShiga toxinHeat labile toxin  <response>: Ans. B. Pertussis toxin.a. Pertussis toxin is a 105 kDa protein composed of six subunits:b. S1 A subunit and B subunit consisting of S2, S3, 2 S4, and S5.c. Pertussis toxin is the most important virulence factor- helps it to evade phagocytes by inhibiting their phagocytic function and helps the bacterium to bind host cells. 