enzyme Article

What is an enzyme?

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  • An enzyme is a substance that acts as a catalyst in living organisms, regulating the rate at which chemical reactions proceed without itself being altered in the process.
  • The biological processes that occur within all living organisms are chemical reactions, and most are regulated by enzymes.
  • Without enzymes, many of these reactions would not take place at a perceptible rate.
  • Enzymes catalyze all aspects of cell metabolism. This includes the digestion of food, in which large nutrient molecules (such as proteins, carbohydrates, and fats) are broken down into smaller molecules; the conservation and transformation of chemical energy; and the construction of cellular macromolecules from smaller precursors.
  • Many inherited human diseases, such as albinism and phenylketonuria, result from a deficiency of a particular enzyme.