<prompt> Gas gangrene is caused by:Clostridium botuliumClostridium perfringensClostridium difficileClostridium tetani  <response>: Ans: B Clostridium perfringens Ref: Ananthnarayan R, Paniker CKJ. Textbook of Microbiology. 8th Edition. Hyderabad: Universities Press; 2X9. Pg. 251Explanation:Gas gangreneCaused byCl. perfringensCl. septic uniCl. odematieunsCl. sporogenesCl histolyticum Aerotolerant anaerobeVirulence factorsExotoxins - hemolytic, lethal and necrotic effects, help in spreading of the infectionAlpha toxin lecithinase -splits lecithinCollagenase KappaHyaluronidase - breaks down hyaluronic acid in muscles celtsTheta toxin haemolysinLeucocidin - kills leucocytesGamma, delta, theta, lambda, mu eta toxinFood poisoningGastroenteritis - Cl. perfringens type ANecrotising enterocolitis - Cl. perfringens type C Botulism - Cl. botulinum Acute colitis Antibiotic associated diarrhoea - Cl. Difficile 