Enzymes: All About Them

Enzymes offer many benefits for our body. In fact without them, life would be impossible because they play an important role in catalzying reactions.

Catalysis refers t othe increase in reaction time without being consumed by the reaction.

An enzyme is just that.


  • Increase the reaction rates 106 – 1012 times faster than uncatalyzed reactions
  • Typically are faster than chemical catalysts
  • And unlike chemical catalysts, enzymes can function under mild conditions
  • Have high specificity for substrate
  • Can be regulated
  • Are also reversible

Six Types of Enzyme Classes:

  • Oxidoreductase – catalyzes redox reactions
  • Transferase – transfers funcional groups between molecules
  • Hydrolase – hydrolyze (break) bonds with water
  • Lyase – Catalyze addition and elimination reactions
  • Isomerase – catalyzes isomerizations
  • Ligase – joins molecules together, usually requires ATP

Substrate Specificity:

Substrates bind enzymes by:

  • H-bonds
  • Hydrophobic interactions
  • Electrostatic interactions
  • Sometimes by metal ion coordination

Cofactors and Coenzymes:

A cofactor is a small molecule or ion required by an enzyme to function

Co-enzyme = cofactor that is a small organic molecule

  • Co-substrate = coenzyme that only associates with the enzyme transiently (for a short period of time)
  • Prosthetic group is a coenzyme that permanently (covalently bonds) with the enzyme

Active enzymes with their appropriate cofactors are called holoenzymes

Inactive enzyme missing their cofactors are called apoenzymes

If you have any questions or would like to share your reviews on the Enzymes, then comment down below. I would love to hear what you have to think.

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