Book def is Any long molecule composed of small repeating units bonded together.
A small organic molecule with a central carbon atom bonded to an amino group, a carboxyl group, a hydrogen atom and a side group. Proteins are polymers of 20 common amino acids. (side chain is what differs between types of amino acid)
covalent bond between carboxyl group of one amino acid and the amino group of the amino acid next to it. (Covalent Bond)
4 basic levels of organization of protein structures.
sequence of amino acids (order matters)!!
What if primary structure changes?
Each amino side chain has specific properties. The change of a single amino acid would change the function. Example is sickle cell disease.
results from hydrogen bonding between the carboxyl oxygen of one amino acid and the amino hydrogen of another. This is where the structure starts to becomes more 3-d like.
Alpha helix is spirally Beta sheets are more straight.
Alpha Helix / Beta sheets
Proteins can have these multiple secondary structures.
interactions involving amino acid side chains. Hydrogen bonds / hydrophobic interactions. Hydrophobic parts will start to fold inside cause fuck that water.
2 or more protein subunits will form a single functional protein.
Primary, secondary, tertiary, Quaternary (happens all at once.)
Proteins that help other proteins fold
Will proteins function if they are not folded?
No. Proper folding is required for functioning
Most proteins function as enzymes.
They start chemical reactions, lower activation energy and are not consumed in the reaction.
Temperature affects on enzyme function
movement of substrates and enzyme
Certain types of enzymes do better in specific temperatures.
pH affects on enzyme function
ideal temp and pH depends on environment of organism.
They are reactants that bind to active site of enzyme. enzyme binds only specific substrates.. not just to anything.
Steps of enzymatic catalysis
1. reactants bind to the active site
2.interactions between the substrate and active site lower the activation energy.
3. Reaction products are released from the enzyme.
Coenzymes / cofactors
additional factors required for normal enzyme function. (such as vitamins and minerals.)
molecules similar in size and shape to the substrate will compete with the substrate for active site binding. This is a way to turn unneeded enzymes off "binds and blocks"
Molecule causes a change in enzyme shape by binding to the enzyme at a location other than the active site. closes enzyme active site, but can be reopened by other regulatory molecules.
Series of enzymatic reactions
Product of reaction one becomes substrate of reaction two...
a regulation method for biochemical pathways.
If final product is abundant they don't waste energy by making more. Final product will bind to first enzyme to shut down chain. Can be restarted if more product is needed.