Lecture 14: Protein Structure and Function Flashcards
What role do proteins play in the body?
Proteins are the workforce of the body, responsible for carrying out essential biological functions.
What are amino acids?
Amino acids are the building blocks of proteins, each containing an amino (NH₂) group, a carboxyl (-COOH) group, and a side chain.
Describe the primary structure of proteins.
The primary structure of proteins refers to the sequence of amino acids, known as residues, that are linked together in a polypeptide chain.
Explain the secondary structure of proteins.
The secondary structure involves the localized folding of the polypeptide, which can form structures such as alpha helices and beta sheets, stabilized by hydrogen bonds.
How do amino acids polymerize to form proteins?
Amino acids polymerize through peptide bonds, linking the amino group of one amino acid to the carboxyl group of another, forming a polypeptide chain with a byproduct of water.
Define the tertiary structure of proteins.
The tertiary structure is the complete three-dimensional folding pattern of a polypeptide, determined by interactions among the side chains of the amino acids.
What is the quaternary structure of proteins?
The quaternary structure refers to the assembly of multiple polypeptide chains into a single functional protein complex, such as hemoglobin, which is a tetramer.
Explain the significance of the hydrophobic effect in protein folding.
The hydrophobic effect describes how non-polar side chains interact with the aqueous environment, leading to their burial in the protein’s interior, which is crucial for proper folding.
Differentiate between globular and fibrous proteins.
Globular proteins are compact, highly folded, and functional, while fibrous proteins are elongated and structural, such as actin and collagen.
Describe the role of hydrogen bonds in protein structure.
Hydrogen bonds are crucial for stabilizing protein structures, particularly in the secondary structure, where they form between the carboxyl oxygen and the N-H donor.
What are the N-terminus and C-terminus of a protein?
The N-terminus is the left-hand side of the polypeptide chain, containing the amino group, while the C-terminus is the right-hand side, containing the carboxyl group.
Identify the forces involved in maintaining protein structures.
Forces involved in maintaining protein structures include hydrogen bonds, electrostatic interactions, disulfide bonds, and the hydrophobic effect.
Explain the characteristics of charged amino acids.
Charged amino acids are hydrophilic, meaning they interact well with water and are often found on the surface of proteins.
How does the sequence of amino acids affect protein function?
The sequence of amino acids determines the protein’s structure, which in turn dictates its specific function in the body.
What is a dimer in the context of protein structure?
A dimer refers to a protein complex formed by the association of two polypeptide subunits.
Describe the role of weak interactions in protein folding.
Weak interactions, such as hydrogen bonds and van der Waals forces, play a significant role in stabilizing the folded structure of proteins.
Explain the function of salt bridges in proteins.
Salt bridges in proteins are bonds between oppositely charged residues that are sufficiently close to each other to experience electrostatic attraction
Define disulfide bonds and their significance in proteins.
Disulfide bonds are covalent bonds formed between the sulfur atoms of two cysteine amino acids, providing structural stability to proteins.
How do hydrophobic interactions influence protein structure?
Hydrophobic interactions cause non-polar side chains to cluster away from water, contributing to the folding and stability of protein structures.
Explain the process of denaturation in proteins.
Denaturation is the process where proteins lose their three-dimensional structure and function, often due to changes in pH, temperature, or salt concentration.
Describe the impact of temperature on protein structure.
Temperature changes can lead to protein denaturation, with the exception of disulfide bonds which remain intact under heat.
How do hydrophobic amino acids behave in aqueous environments?
Hydrophobic amino acids tend to be exposed to water, leading to their clustering and becoming insoluble, which affects protein folding.
Outline the steps involved in the drug discovery pipeline.
The drug discovery pipeline includes
Target Identification & Validation
Drug Discovery & Screening
Lead Optimization
Preclinical Development
Clinical Trials.
What is the role of GWAS in drug discovery?
GWAS (Genome-Wide Association Studies) helps in identifying genetic variants associated with diseases, aiding in target identification and validation in drug discovery.
