Chapter 4: Proteins Flashcards
What determines the shape of a protein?
amino acid sequence with different chemical properties
What holds the structure of a protein together?
peptide bonds
What are the differences of primary, secondary, tertiary, and quaternary protein structures?
What are enzymes?
proteins that help speed up chemical reactions
How do proteins bind to other molecules?
through weak noncovalent interactions; hydrogen bonds, electrostatic attractions, and van der Waals attractions—plus favorable hydrophobic forces
What determines the specific binding of proteins to other molecules?
the shape of the ligand
What domain of an antibody is responsible for the specific binding of an antigen?
The amino-terminal variable or V domains of the heavy and light chains (VH and VL, respectively) together make up the V region of the antibody and confer on it the ability to bind specific antigen, while the constant domains (C domains) of the heavy and light chains (CH and CL, respectively) make up the C region
N-terminus
end carrying the amino group (NH3)
C-terminus
end carrying the free carboxyl group (-COOH)
Peptide bonds
Covalent bond of carbonyl group (C=O) of an Amino acid bonded to the amino group (-NH3) of another amino acid
nonpolar (hydrophobic) side chains
tend to cluster in the interior of the folded protein
polar side chains—such as those belonging to arginine, glutamine, and histidine
arrange themselves near the outside of the folded protein, where they can form hydrogen bonds with water and with other polar molecules
