<prompt> Which of the following test will differentiate Vibrio cholerae from E.coli?Oxidase testLactose fermentationSensitivity to optochinCatalase test  <response>: Answer: a Oxidase test PANIKER 9th EDITION P-305ENTEROBACTER1ACEAE Grow well in MacConkey media Catalase positive except Shigella dysentriae type 1 Oxidase Urease negative Urease negative except Proteus, Klebsiella, Morganella Motile by peritrichate flagella except Shigella, Klebsiella, Salmonella gallinarum-pullorum Ferment glucose except ShigellaVIBRIO CHOLERAE Comma shaped, gram negative Fish in stream appearance in stained films Darting type of motility Under microscope motile vibrios suggest swarm of gnats NaCI0.5-l is required for optimal growth, though higher concentrations6 are inhibitory Gelatin slab culture infundibulum funnel shapedor napiformturnip shapedjliquefaction occurs Vibrio colonies are identified by string test Catalase ve, Oxidase ve, indole ve, Urease negative Cholera red reaction indole formation nitrate reduction adding few drops of con. Sulphuric acid to alkaline peptone water cultureLactose FermentationOrganismsOccursEscherichia, Klebsiella, EnterobacterDoes not occurShigella, Salmonella; Proteus, PseudomonasOccurs slowlySerratia, Vibrio Optochin test - to differentiate S. Pneumoniae from other alpha-hemolytic streptococci. CAMP test - to identify Group B beta-hemolytic streptococcus and differentiate it from Group A streptococcus Catalase test is used to differentiate staphylococci from streptococci. 