Proteins are a primary constituent of living things and one of the chief classes of molecules studied in biochemistry. Proteins provide most of the molecular machinery of cells. Many are enzymes or subunits of enzymes. Other proteins play structural or mechanical roles, such as those that form the struts and joints of the cytoskeleton. Each protein is linear polymers built of amino acids. Proteins are also nutrient sources for organisms that do not produce their own energy from sunlight and/or are unable to fix nitrogen. Proteins can interact with one another and with others molecules to form complexes.

Index of chapters and main sections

  1. Introduction
    1. Protein role in biology
    2. Proteins as polymers of amino acids
    3. Protein function depends on structure
    4. Protein synthesis
  2. The chemistry of proteins
    1. Amino acid structure and chemistry
    2. Disulfide bonds
    3. Post-translational modifications
  3. Protein structure and folding
    1. What is protein folding?
    2. Protein structural levels
    3. Secondary structure elements
    4. Tertiary structure elements
    5. Common folds and modules
  4. Types of Protein
    1. Oxygen Binding Proteins