Digestive enzyme
Digestive enzymes are a group of enzymes that break down polymeric macromolecules into their smaller building blocks, in order to facilitate their absorption by the body. Digestive enzymes are found in the digestive tracts of animals (including humans) and in the traps of carnivorous plants, where they aid in the digestion of food, as well as inside cells, especially in their lysosomes, where they function to maintain cellular survival. Digestive enzymes of diverse specificities are found in the saliva secreted by the salivary glands, in the secretions of cells lining
Adrian John Brown
He studied the rate of fermentation of sucrose by yeast and suggested in 1892 that a substance in the yeast might be responsible for speeding up the reaction. This was the first time enzymes were suggested as separate entities from organisms and talked about in chemical terms. He later studied the enzyme responsible and made the striking suggestion that the kinetics he observed were the result of an enzyme-substrate complex being formed during the reaction, a concept that has formed the basis of all later work on enzyme kinetics. Similar ideas had been put earlier by German chemist and Nobel laureate Hermann Emil Fischer by comparing substrate and enzyme with a key and a lock.