Doris Lee Even Zheng Joanna Tang Kiki Jang Rachel Zhang Vincent Ma

 Proteins, one of the most important biological molecules in our body. They are included in virtually all of the cell functions.

 Antibodies- are proteins that are specialized to defend our body from antigens  Contractile Proteins- are responsible for movement.

 Enzymes- are catalysts that speed up the biological reactions.  Hormonal Proteins- are messenger proteins which help to coordinate certain bodily activities.  Structural Proteins- are fibers that provide support.

 Storage Proteins- are used to store amino acids.  Transport Proteins- are carrier proteins that circulate other molecule around the body.

♥ proteins are made up of amino acids ♥ amino acids link together to form polymers = proteins

Amino acids are made up of an amino group (-NH 2 ) and a carboxylic acid group (- COOH), distinguished by the attached functional group R. The key elements of amino acids are Carbon, Hydrogen, Oxygen and Nitrogen. The most common amino acid is shown above, with a carbon atom attached to the carboxyl group, called an alpha amino acid.

Amino acids have properties of both acids and bases. The amino group gives the amino acids its basic properties and the carboxyl group gives amino acids its acidic properties. R represents a group called a side chain which varies from one amino acid to another. It distinguishes an amino acid as a weak acid or a weak base, and a hydrophile if the side-chain is polar or a hydrophobe if it is non-polar.

Peptide bond is a covalent bond that joins 2 amino acid Ex. A polypeptide is a string of amino acids joined by peptide bonds A dipeptide results when 2 amino acids join and also forms water as a by product dipeptide formation

The differences between primary, secondary, tertiary, and quaternary structure The differences between primary, secondary, tertiary, and quaternary structure

 Composed of amino acids → polypeptide chains  a slight change in the structure can effect the appearance and function of the protein  ex. Blood cell → sickled cell

 is made up of repeated coils and folds of polypeptide chains  result of hydrogen bonds at regular intervals along polypeptide backbone  two types: helix pleated sheet

 superimposed on the patterns of secondary structures  contortion caused by the interaction in side chains of amino acids

 2 types of interactions  hydrophobic: clustering of hydrophobic group away from water  Van de Waals : weak bonds between side chains that hold the protein in a specific conformation  the appearance of the structure can be reinforced by a covalent bond called disulfide bridges

 result from the aggregation of polypeptide subunits  made up of primary, secondary, and tertiary structures

 Primary Structure is a sequence of amino acids (line)  Secondary Structure is pleated sheet or helix (flat and 2D)

 Tertiary structure is 3D  Quaternary is more complicated, combined with different protein structures

_jpg.html _jpg.html and-normal-red-blood-cells and-normal-red-blood-cells PrimaryStructure.html PrimaryStructure.html EWORK/ /courseworks.htm EWORK/ /courseworks.htm ure.html ure.html e/chemistry/chemistry8.htm e/chemistry/chemistry8.htm ture.html ture.html a.htm a.htm