COAGULASE TEST AIM To differentiate Coagulase positive Staphylococcus aureus from Coagulase negative Staphylococcus sp. ( Staphylococcus epidermis and Staphylococcus saprophyticus ). PRINCIPLE Coagulase is an enzyme that works in conjugation with normal plasma components to convert Fibrinogen to Finbrin and causes Clotting of Plasma. This enzyme is a good indicator of pathogenic potential of Staphylococcus aureus . As 97 % of the strains of Staphylococcus aureus have proven to be Coagulase positive, the Coagulase test is useful for differentiating Staphylococcus aureus from other Gram positive, Catalase negative cocci. Staphylococcus aureus produces two types of Coagulases. First one is Bound Coagulase and the Second one is Free Coagulase. Slide coagulase test is done to detect Bound coagulase, whereas Tube coagulase test is done to detect Fre...