Catalase negative member of the family Enterobacteriaceae is (NOT RELATED): (A) Salmonella typhi, (B) Proteus vulgaris, (C) Shigella dysenteriae serotype 1, (D) Escherichia coli
Answer is C. The general finding that members of the family enterobacteriaceae produce catalase has impoant exceptions in Shigella dysenteriae serotype 1 and a few strains of Shigella flexneri (mostly in serotype 4a) which are catalase negative.