KA 2 Flashcards
What are proteins made of?
Proteins are polymers of amino acids, linked by peptide bonds to form polypeptides.
What is the basic structure of an amino acid?
An amino acid has an amino group, a carboxyl group, a hydrogen atom, and an R group (side chain).
What is the difference between amino acids?
Amino acids differ in their R groups, which vary in size, shape, charge, and chemical reactivity.
How are amino acids classified?
Amino acids are classified as:
- Basic (positively charged)
- Acidic (negatively charged)
- Polar (hydrophilic)
- Hydrophobic (non-polar)
What determines a protein’s function?
A protein’s function is determined by the sequence of amino acids (primary structure) and the interactions between their R groups.
What is the primary structure of a protein?
The primary structure is the sequence of amino acids in a polypeptide chain.
What is secondary structure in protein folding?
Secondary structure refers to local folding patterns in the polypeptide, such as alpha helices and beta-pleated sheets, stabilized by hydrogen bonds.
What is the tertiary structure of a protein?
The tertiary structure is the overall 3D shape of a protein, stabilized by interactions between R groups (hydrophobic interactions, ionic bonds, etc.).
What is quaternary structure in proteins?
Quaternary structure is the arrangement of multiple polypeptide subunits in a protein (e.g., hemoglobin has four subunits).
What is denaturation?
Denaturation is the unfolding of a protein due to disruption of its structure, caused by changes in temperature or pH, leading to loss of function.
How do changes in temperature and pH affect protein structure?
High temperature and extreme pH can disrupt the bonds holding a protein’s structure, causing it to unfold and lose function.
What is ligand binding in proteins?
Ligand binding is the process where a molecule binds to a protein, often causing a conformational change that alters the protein’s function.
What is allosteric regulation?
Allosteric regulation occurs when a molecule binds to a site on a protein other than the active site, changing the protein’s activity.
What is cooperativity in proteins?
Changes in binding at one subunit alter the affinity of the remaining subunits.
How does pH affect oxygen binding in hemoglobin?
A decrease in pH (more acidic) reduces hemoglobin’s affinity for oxygen, promoting oxygen release in tissues with higher metabolic activity.
What is phosphorylation in protein regulation?
Phosphorylation is the addition of a phosphate group to a protein, which can cause a conformational change, activating or inhibiting the protein.
What do protein kinases do?
Protein kinases add phosphate groups to specific R groups of proteins, often to regulate their activity.
What do protein phosphatases do?
Protein phosphatases remove phosphate groups from proteins, reversing the effect of phosphorylation.
How does phosphorylation affect protein function?
Phosphorylation can activate or inhibit proteins by altering their shape and function through the addition of negative charges.
What is the role of allosteric enzymes?
Allosteric enzymes have both active and allosteric sites, where binding of modulators can alter enzyme activity by changing its shape.
What is the proteome
Entire set of proteins expressed by genome
What is the name given to genes that Do not code for proteins?
Non-coding RNA
Factors that can affect the set of proteins expressed by given cell type
Metabolic activity, cellular stress, response signalling, disease versus healthy
What is the location of lipid synthesis within cell
Smooth E.R
