This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Microbiology
Shigella can be differenciated from E.Coli by all of the following features except - 
Select and explain. 
A. Shigella does not produce gas from glucose, B. Shigella does not ferment lactose, C. Shigella does not ferment mannitol, D. Shigella has no flagella is non motile
C: Shigella does not ferment mannitol
Answer: C: Shigella does not ferment mannitol 
Explanation: Ans. is 'c' i.e., Shigella does not ferment mannitol . Fermentation of mannitol is of impoance in classification and shigellae have traditionally been devided into mannitol fermenting and nonfermenting species. E coli Shigella Morphology --> . Capsulated . Gram negative . Motile (by peritrichate flagella) . Fimbriae are found . Non capsulated . Gram negative . Non motile (lack flagella) . Fimbriae may be present Biochemical reactions --> . Lactose is fermented . Glucose is fermented with the production of acid and gas. . Mannitol fermented . IMViC --> + + - - (Indole, methyl red, Voges - Proskauer and citrate) . Lactose is not fermented except shigella sonnei, which ferment it late * Glucose is fermented with the production of acid, without gas except for the New castle and Manchester biotypes of Sh. flexneri, and some strains of Sh. boydii type 13 and 14, which from gas . Mannitol fermented except Sh. dysenteriae . MR --> (+) ve Citrate --> (-) ye VP --> (-) ve Indole ----> Sh. Sonnei (-) ye other show variable reaction Culture --> . Produce pink colonies on MacConkey's medium due to lactose fermentation . Deoxycholate medium (DCA) inhibits the growth . Produce colourless colonies on MacConkey's medium due to lack of lactose fermentation except S. sonnei which ferment it late and produces pink colonies. . DCA is selective medium