Denature: folded wrongly, usually happens because of heat.

Folding and shape: Protein folding and structure affect functions

Hydrophobic and Hydrophilic regions also affect how they interact with other chemicals like in a cell membrane, where the hydrophilic regions would be facing out of the cell.

Primary Structure:
The simple linear order of the amino acids.

Secondary Structure:
Places where the polypeptides bond together to fold over each other.
The terminals react with each other.

Beta pleated sheet:
Places where the polypeptides are in parallel or antiparallel HYDROGEN-BONDS will happen between the CO- and NH-groups.

Alfa Helix:
A hydrogen bond between a CO-group and an NH-group with exactly FOUR amino acids after the first one.

Tertiary Structure:
Actual covalent and other bonds form between the strands of polypeptides
The R-group reacts with each other.

Quaternary Structure:
Only happens in a few, but it is when MULTIPLE polypeptide chains that stick together in a complex.
Example:
Hemoglobin, which is made out of four chains held together by iron molecules.

The building blocks of proteins, there are 20 total, 12 of which we can create ourselves, and ORDER matters!

Uses of proteins:
Enzymes, antibodies, signaling hormones, actin and myosin (cytoskeleton), transport of Oxygen (Hem)

Amino group (Terminus):
H3N

Carboxyl group (Terminus):
CO2, but not the exact same, as it is negatively charged.

R group:
The group that decides what it is, for example, some R’s might be hydrophobic or have a negative charge, etc.

Zwitterion:
A molecule that is neutral, but has parts that are charged, amino acids are perfect examples.

New amino acids: Can ONLY be added to the carboxyl terminus.
They create covalent/peptide bonds.