Gibbs Free Energy Overview

What does Gibb's Free Energy represent in a molecule?

Which type of energy is NOT explicitly mentioned as available for work in a molecule?

Which of the following is a source of energy within a molecule?

Energy stored in bonds between atoms is primarily classified under which category?

Which of the following statements is true regarding Gibb's Free Energy?

What are the main components of an amino acid's structure?

How can side chains of amino acids be classified?

The reaction that connects amino acids together is called __________.

The reaction that breaks down proteins by adding a water molecule is called __________.

What is the primary structure of a protein?

Which level of protein structure involves hydrogen bonding and forms structures such as alpha helices and beta-pleated sheets?

What four types of interactions contribute to the tertiary structure of a protein?

What defines the quaternary structure of a protein?

What role do chaperone proteins play in relation to protein folding?

What could be a potential consequence if the primary structure of a protein is altered?

Gibbs Free Energy (G)

Gibbs free energy (G) is the energy within a molecule available for work.
Not all energy within a molecule is usable for work.
Examples of energy within a molecule include:
- Vibrations
- Rotations
- Chemical potential energy stored within bonds between atoms.

Amino Acid Structure

Amino acids are the building blocks of proteins.
Each amino acid has a central carbon atom, an amino group, a carboxyl group, and a side chain that varies.
Side chains can be classified as nonpolar, polar uncharged, or polar charged based on their properties.

Peptide Bonds

Amino acids are linked together by peptide bonds through a condensation reaction.
This process removes a water molecule.
The opposite reaction, hydrolysis, breaks peptide bonds by adding a water molecule.

Levels of Protein Structure

Primary structure is the sequence and length of amino acids in a protein.
Secondary structure is the local folding of the polypeptide chain, including alpha helices and beta pleated sheets.
Tertiary structure is the overall three-dimensional shape of a single polypeptide chain, stabilized by interactions between side chains.
Quaternary structure refers to the arrangement of multiple polypeptide subunits in a protein.

Interactions in Protein Folding

Hydrophobic interactions: Non-polar side chains cluster together, avoiding water.
Hydrogen bonding: Hydrogen bonds form between polar side chains.
Disulfide bridges: Covalent bonds form between cysteine residues.
Electrostatic attraction: Opposing charges on side chains attract each other.

Chaperones

Chaperone proteins assist in the proper folding of proteins.
They help prevent misfolded proteins, which can be harmful.

Consequences of Altered Structure

Any change to the primary structure of a protein can affect its higher-order structures and ultimately its function.
This can lead to loss of activity, aggregation or misfolding, and other consequences.

This quiz explores the concept of Gibbs free energy (G) and its significance in thermodynamics. It covers the different forms of energy within a molecule, including vibrations, rotations, and chemical potential energy. Test your understanding of how the energy in molecules is available for work.