Protein Structure & Function Flashcards
Functions of Proteins
- Catalysts
- Transports
- Storage of Molecules
- Mechanical Support
- Generate Movement
- Transmit Signals
Protein molecules adopt a specific
three-dimensional conformation
Native Fold
The 3D structure of a protein that is properly folded and functional
Favorable Interactions in Proteins
- Hydrophobic Effect
- Hydrogen Bonds
- London Dispersion
- Electrostatic Interactions
Hydrophobic Effect
The release of water molecules from the structured solvation layer around the molecule as protein folds increase the net entropy
Hydrogen Bonds
Interaction of N - H and C = O of the peptide bond leads to local regular structures such as alpha helices and
beta sheets
London Dispersion
Medium-range weak attraction between all atoms contributes significantly to the stability in the interior of the protein
Electrostatic Interations
Long-range strong interactions between permanently charged groups
Four Levels of Protein Structure
Primary
Secondary
Tertiary
Quaternary
Amino Acid Structure
Amino Group (NH3+)
Carboxyl Group (CO2)
Hydrogen
R-Group (Variant)
Nonpolar R groups are found in
Hydrophobic amino acids
Neutral R Groups are found in
Polar amino acids
Positively charged R groups are found at
Physiological pH
Negatively charged R groups are found at
physiological pH
*Ex. of Hydrophobic amino acids
Glycine
Alanine
Leucine
Valine
