E. Catalase Activity. Catalase is the name of an enzyme found in most bacteria which initiates the breakdown of hydrogen peroxide (H2O2) into water and free oxygen. 1  If the bacterium produces the enzyme catalase, then the hydrogen peroxide added to the culture will be broken down into water and free oxygen. If the bacterium produces the enzyme catalase, then the hydrogen peroxide added to the culture will be broken down into water and free oxygen. 2  The oxygen will bubble through the water causing a surface froth to form. 3  This is a catalase-positive bacterium (see fig.
Still, the proverb has been widely (although not accurately) attributed to Eugene OâNeill who included it in his 1920 play Diffârent. The full quote by OâNeill is, âCuriosity killed the cat, but satisfaction brought it back.â.
The saying originally was care kills a cat, and began in the 16th century. Care was a warning that worry is bad for your health and can lead to an early grave; the phrase was a recognition that cats seem to be very cautious and careful. Over time, the word care evolved into curiosity..