String of Pearls Concept
Diagram illustrating protein formation.
Each gray circle represents an amino acid.
Connecting bonds are covalent bonds called peptide bonds.
Unique covalent bonds formed between amino acids.
Example diagram shows 4 amino acids connected by 3 peptide bonds.
Bonds form between the amino terminus (NH2) and carboxyl terminus (COOH) of amino acids.
The carboxyl group loses an -OH and the amino group loses an -H, releasing water as a byproduct.
Importance of considering protein interactions in aqueous environments due to water generation.
Primary Structure: Sequence of amino acids linked by peptide bonds.
Secondary Structure: Formation of coils and folds.
Alpha Helix: Coiled structure; created by twisting the string of pearls.
Beta Sheets: Layers formed by folding the string of pearls.
Hydrogen bonds contribute to protein’s secondary structure.
Distal amino acids form hydrogen bonds, aiding in structural stability.
Alpha Helix: Consists of hydrogen bonds between amino acids in the same segment.
Beta Sheet: Involves hydrogen bonds between distant segments of the polypeptide chain.
Carbon Backbone: Essential for forming complex proteins.
Carbon atoms can form four covalent bonds, allowing for diverse functionality.
Alpha carbon is chiral: functional groups around can rotate, affecting protein shape.
Involves folding of the polypeptide into a three-dimensional shape.
Interactions include:
Hydrophobic and Hydrophilic Interactions: Determine orientation relative to water.
Ionic Bonds: Between charged amino acids.
Hydrogen Bonds: Stabilize folded structure.
Covalent Bonds: Less common; includes disulfide bridges between cysteine residues.
Van der Waals Forces: More significant in larger proteins.
Some proteins are formed from multiple polypeptide chains.
Example: Hemoglobin comprises four subunits and a metal ion.
DNA Polymerase: Composed of multiple enzymes; not a single entity.
Denaturation: Protein structure can change based on the environment (e.g., temperature, pH).
Example: Cooking an egg white (albumin) causes it to solidify due to denaturation.
Enzymes lower activation energy rather than speeding up chemical reactions.
Reaction likelihood is increased, leading to more product formation without altering the time it takes.
Enzymes operate with cofactors which can be minerals (e.g., magnesium).
Malfunctioning Enzyme: Produces a toxin proportional to enzyme activity.
Control over patient symptoms needs consideration of enzyme cofactors and temperature at which the enzyme is active (37°C).
Focus on reducing enzyme activity or managing symptoms with knowledge of enzyme requirements for function (e.g., magnesium).
Considerations for treatments include dietary adjustments or enzyme inhibitors based on activity levels determined through study.