Nucleic Acids and Proteins

Protein

Diverse Polypeptide biomacromolecules crucial to functioning and development of living organisms.

Polypeptide

polymer chain of amino acid monomers joined by peptide bonds to make up a protein

Proteome

All proteins expressed by organism at a given time

Enzyme

Organic catalysts typically made of proteins, that catalyse chemical reactions.

Transport proteins

Proteins typically embedded in membranes controlling entry and exit of substances from cell

Structural proteins

Proteins which support cell and tissue shape, such as keratin, elastin and collagen.

Peptide hormones

Chemical messengers that regulates physiology and induce changes to cells.

Receptors

Proteins that receive signals from the environment

Defence proteins

Proteins involved in the immune system, recognising and destroying pathogens

Antibody

Protein produced by plasma cells in adaptive immune response specific to an

Condensation reaction

Joining of amino acids at cells ribosome resulting in the formation of peptide bonds between adjacent amino acids

Peptide bond

Chemical bond between adjacent amino acids formed via a condensation reaction at the cells ribosome.

Amino acid

Monomers which join together into a polypeptide chain to form a protein.

Amino Acid structure

Central carbon atom bonded to a hydrogen atom, carboxyl group, amino group, and R group

R group

Variable portion of amino acid with 20 potential variations of different properties, determining the identity of an amino acid and how amino acids interact with each other.

Protein structure

The shape of a protein determining its functionality.

Primary structure

A sequence of amino acids in a polypeptide chain.

Secondary structure

Polypeptide chain coils and folds due to bonds between amino acids of different sections forming Alpha Helices, Beta Pleated Sheets, and Random coils

Alpha Helices

Organised, coiled secondary structures of proteins formed

Beta pleated sheets

Organised, folded secondary structure of proteins

Random coil

Irregular secondary structure of proteins joining alpha helices and beta pleated sheets.

Tertiary structure

Functional 3D shape of a protein formed by bonds and interactions between amino acids and r groups of different sections, such as disulphide bonds if R groups contain sulphur atoms.

Disulphide bonds (structure)

Strong covelant bonds between amino acids containing sulphur atoms in their R groups, stabilising 3D structure

Quaternary

Two or more polypeptide chains with tertiary structure join together, or one has a prosthetic group.

Prosthetic group

A non protein group bound to a protein, makes a tertiary protein quaternary.

Haemoglobin

Protein with quaternary structure, containing four polypeptide chains and a haem prosthetic group with an iron embedded in each, responsible for carrying oxygen in red blood cells.

Importance of primary structure

Determines the folding of protein into functional structures. Sequence and order of amino acids determines interactions between R groups, which form bonds that favor folding into specific 3D structure.