[04] Protein Structure and Function Flashcards
What is a protein?
A macromolecule composed of amino acids linked by peptide bonds
What are the building blocks of proteins?
Amino acids
What forms a peptide bond?
The carboxyl group of one amino acid and the amino group of another
What are the four levels of protein structure?
- Primary
- Secondary
- Tertiary
- Quaternary
What is the primary structure of a protein?
The sequence of amino acids in a protein
What is the secondary structure of a protein?
The local folding pattern of the protein backbone, such as alpha-helices and beta-sheets
What is the tertiary structure of a protein?
The overall three-dimensional shape of a protein
What is the quaternary structure of a protein?
The assembly of multiple polypeptide chains into a functional protein complex
What are the roles of proteins in the body?
- Enzymes
- Structural proteins
- Transport protein
- Immunoproteins
- Hormones
- Storage proteins
How is protein structure related to its function?
The specific shape of a protein determines its function and interaction with other molecules
What is protein denaturation?
The process where a protein loses its native structure due to changes in temperature, pH, or chemical environment
What is a protein domain?
A segment of a protein that can fold independently into a compact, stable structure
What are globular and fibrous proteins?
- Globular proteins → proteins that are generally water-soluble and spherical in shape
- Fibrous proteins → proteins that are generally insoluble and have a structural role
What is an enzyme?
A protein that acts as a biological catalyst to accelerate chemical reactions
What is the active site of an enzyme?
The region of an enzyme where substrate molecules bind and undergo a chemical reaction
What are cofactors and coenzymes?
- Cofactors → non-protein chemical compounds required for an enzyme’s activity
- Coenzymes → organic molecules that assist enzymes during the catalysis of reactions
What is an allosteric site?
A region in an enzyme other than the active site, where the binding of a molecule can change the function of the enzyme
What is protein folding?
The process by which a protein structure assumes its functional shape or conformation
What is a chaperone protein?
A protein that assists in the folding of other proteins
What is a prion?
A misfolded protein that can trigger normal proteins to fold abnormally
Give an example of a cofactor.
Iron (Fe) in hemoglobin
Give an example of a coenzyme.
Vitamin B12 in methionine synthase
