Enzymes

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Enzymes
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What are enzymes?

• Enzymes are proteins that act as biological
  catalysts and allow certain reactions to take
  place.
• A Catalyst is a substance that speeds up a
  chemical reaction without becoming part of that
  reaction.

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• They are not altered during the course of
  chemical reactions.
• Enzymes operate within a narrow range of pH and
  temperature. They can be destroyed, or denatured
  if the temperature or pH changes too dramatically.

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• They are specific for the substance they
  catalyze, called a substrate. They are associated
  with the substrate molecule as a key is
  associated with a specific lock. This is called
  the Lock and Key Theory.

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Characteristics of Enzymes

• They can speed up the rate of reactions.
• They lower the activation energy needed for the
  chemical reaction to happen.

The energy hill is lowered by the enzyme.
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• The enzyme has a molecular fit to the substrate
  at a place on the enzyme called the active site.

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• The Enzyme and substrate fit together during the
  reaction to form a enzyme-substrate complex.
  This is a very temporary situation which lasts an
  instant. The substrate is converted to products.

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• The enzyme may catalyze many thousands of
  reactions in a second!
• The enzyme is free to catalyze again and again in
  reactions as needed.

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ASE

• Many enzyme names end in ase
• Enzyme Substrate
• sucrase sucrose
• lactase lactose
• lipase lipids
• amylase amylose (starch)
• reverse transcriptase certain virus RNA