Topic 3 Amino Acids, Proteins, and Enzymes Flashcards
Common functions of Proteins
movement, hormones, enzymes, transport, immune system, structure
Nonpolar part of amino acid
hydrophobic. Located inside of proteins away from the aqueos environment. The way you can tell is a lot of hydrocarbons.
Polar uncharged amino acid
hydrophilic. Typically on the outside of the protein in contact of an aqueous environment. Lots of hydrogen bonds
Polar charged amino acids
acids and bases. Located on the outside typically in contact of an aqueous environment. R group negative = acid - R Group positive = base.
What type of bond holds amino acids together?
Peptide bond, amino group of one amino acid is bonded to the carboxyl group of another amino acid. Does not change the properties of amino acid.
Primary structure
Polypeptide chain. Proteins assembled from mRNA starting at the N-terminus and ending at C terminus. Big role in protein shape
Secondary structure
The alpha helix when the CO and NH of different peptide bonds from hydrogen bonds. Beta sheet form when CO and NH of different peptide bonds form hydrogen bonds, lying side by side.
tertiary structure
R group determines how protein is folded. Largely determined by noncovalent interactions. Hydrophobic middle, hydrophillic surface.
Quaternary structure
different tertiary structure come together to form
Prions
Protein folding gone wrong. Normally random coil and alpha helix. Configuration can non-covalently interact with other proteins making them misfold. Beta sheets line up and form insoluble structures which can kill cells.
What are IDP and IDRs
IDPs = intrinsically disordered proteins, disordered structures
IDRs = intrinsically disordered regions, portions are disordered.
Regions are usually made of charged polar amino acids and new proteins to adapt to their structure.
Why are enzymes important?
Most chemical reactions that are necessary happen slowly, enzymes can speed up reactions
Two important properties of catalysts
1) Not consumed or permanently altered in the process
2) Do not alter the chemical.
How do Enzymes speed up a reaction?
Enzymes decrease energy needed for the transition state making it easier for the reaction to take place. Create an environment that favors the reaction to occur. The substrate binds to active site of the enzyme
What are cofactors?
class of molecules that can help enzymes participate in catalysis
What are coenzymes?
A subset of cofactors. Bind loosely to enzymes, and recycles during catalysis.
What is prosthetic group?
Bind tightly to enzymes. Inorganic or organic molecules. A subset of cofactors.
describe allosteric regulation
small molecules non covalently binding to sites other than active site regulate the activity of enzymes by changing the shape of enzyme.
describe feedback inhibition
the product inhibits an enzyme needed for its synthesis. Cell’s ability to regulate the product being produced.
what are protein kinases and phosphatases?
Kinases: Proteins that can phosphorylate other proteins
Phosphatases: proteins that can dephosphorylate other proteins.
