Card Set Information
Protein structure (linkage)? Functions?
condensation polymers, polyamide of amino acids (aka peptide bonds)
Structure, contraction (myofilament), transport (hemoglobin), energy storage, hormones (GH, insulin), enzymes, protections (IgE)
General amino acid structure. α, ϐ, etc? L vs R?
α, ϐ, etc refer to C that amine is located on. Proteins use α amino acids
L/R refer to location of NH
L amino acids are "natural"
# of amino acids? Essential?
Categories of amino acids w/ types of R groups and pI
: hydrocarbon, benzene ring; pI 6
: SH, OH, amide; pI 6
: additional COOH; pI 3
: additional NH
; pI 10
isoelectric point - The pH at which the zwitterion is formed
Net charge = 0
Neutral, acidic, and basic amino acids at pH 1, 3, 6, 10, 12
: 1 (+1), 3 (+1), 6 (0), 10 (-1), 12 (-1)
: 1 (+1), 3 (0), 6 (-1), 10 (-2), 12 (-2)
: 1 (+2), 3 (+2), 6 (+1), 10 (0), 12 (-1)
How would each type of amino acid react in electrophoresis, gel pH 6?
Neutral AA (no charge) - stays stationary
Acidic AA (negative) - moves toward cathode
Basic AA (posative) - moves toward anode
end of amino acid
: COOH end of amino acid
Various lengths of amino acids and names
: dipeptide, tripeptide,..., octapeptide
How are amino acid sequences written? How to determine amount of possibilities?
sequenced in order, left to right (N-terminus on left)
Total amount of possabilities = n! where n = # of amino acids
n! = n·(n-1)·(n-2)·(n-3)·,...,·1)
Primary protein structure
Number, type, and sequence of AA
Determined by applying HCl to protein which breaks all bonds allowing determination of number and type of AA.
Other chemicals react with different AAs to produce varied lengths and breakages, a combination of this information will lead to the correct sequence
Secondary Protein Structure
H bonding in the back bone
Alpha helix - every 3-5C H-bonding between carbonyl and amine of another AA
Beta pleated sheet - A sort of "bent" alpha helix
vanderwalls, H bonding, disulfide bridge, electrostatic interactions (between R groups)
Gives overall 3D form with hydrophobic R facing in and hydrophilic R facing out
Van der walls, H bonding, electrostatic interactions (between multiple tertiary structures)