#active_site  the part of an enzyme or antibody where the chemical reaction occurs
  supertype:  site__situation  physical position in relation to the surroundings
  part of:  enzyme  any of several complex proteins that are produced by cells and act as catalysts in specific biochemical reactions
  part of:  antibody  any of a large variety of immunoglobulins normally present in the body or produced in response to an antigen which it neutralizes, thus producing an immune response

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