ABSTRACT

Protein Structure ........................................................................................................5 Classification of Proteins...................................................................................5 Amino Acids ......................................................................................................6 Primary Protein Structure ..................................................................................7 Protein Secondary Structure ..............................................................................9 Tertiary and Quaternary Structure in Globular Proteins.................................12

Protein Biosynthesis ................................................................................................14 Messenger RNA and RNA Polymerase ..........................................................14 mRNA Processing............................................................................................16 The Genetic Code............................................................................................17 Activated Amino Acids and Transfer RNA ....................................................18 The Ribosome and Associated Factors ...........................................................19 Message Translation and Protein Synthesis....................................................20

Protein Modification ................................................................................................21 Types of Modification......................................................................................21 Protein Transport and Modification ................................................................22

Protein Stability .......................................................................................................22 The Importance of Noncovalent Interactions..................................................22 Types of Noncovalent Interactions..................................................................23 The Hydrophobic Effect ..................................................................................25 Protein Folding and Noncovalent Interactions................................................26 Thermodynamics and Kinetics of Protein Folding.........................................27

Further Reading .......................................................................................................29

Proteins are often put into one of two categories, globular or fibrous, on the basis of their overall structure. Globular proteins have compactly folded structures and tend to resemble globes or spheroids in overall shape. Some are soluble in water and can function in the cytosol or in extracellular fluids; other globular proteins are closely associated with lipid bilayers, being buried in part or in whole in the biological membranes where they function. Globular proteins include enzymes,