Protein Essay
Protein Essay- Erin Keegan
What are proteins?
A polypeptide is a chain of monomers joined up to make a polymer. Proteins are organic polypeptides made up of a chain of amino acid residues- they’re residues because they lose a water molecule. The amino acids (monomers) join up by forming peptide bonds. When two amino acids join together, they become a dipeptide. This happens when the carboxyl group of an amino acid and the amino group of another amino acid link up through a condensation reaction (which involves the removal of a water molecule).
When this process happens at least nine times to form a polypeptide, it is called polymerisation.
The reverse of this condensation reaction can happen by adding a water molecule to break the peptide bond. This process is called hydrolysis.
Protein Structure
Globular Proteins
The chain of amino acid residues you’re left with is called the primary structure of a protein.
The secondary structure of a protein takes form when the chain coils into a αhelix or βpleated sheets. The αhelix structure is called α because if you look down the coil, it turns in a clockwise direction as if spiralling away from you. It becomes a αhelix structure because the chain collapses round on itself due to hydrogen bonding.
The hydrogen bonds form between the C=O and the N-H at every turn because hydrogen, when bonded with a highly electronegative atom such as nitrogen experiences attraction to other nearby highly electronegative atoms, such as oxygen.
Hydrophobic groups cluster together at the centre of the molecule away from any water, this makes them soluble.
The tertiary structure of a protein takes form when the αhelix folds over on itself giving the protein it’s unique three dimensional shape. The secondary structure can fold over itself because of the hydrocarbon side groups represented by “R” in the diagram under “What are proteins?”. These can form ionic or hydrogen bonds with each other
What are proteins?
A polypeptide is a chain of monomers joined up to make a polymer. Proteins are organic polypeptides made up of a chain of amino acid residues- they’re residues because they lose a water molecule. The amino acids (monomers) join up by forming peptide bonds. When two amino acids join together, they become a dipeptide. This happens when the carboxyl group of an amino acid and the amino group of another amino acid link up through a condensation reaction (which involves the removal of a water molecule).
When this process happens at least nine times to form a polypeptide, it is called polymerisation.
The reverse of this condensation reaction can happen by adding a water molecule to break the peptide bond. This process is called hydrolysis.
Protein Structure
Globular Proteins
The chain of amino acid residues you’re left with is called the primary structure of a protein.
The secondary structure of a protein takes form when the chain coils into a αhelix or βpleated sheets. The αhelix structure is called α because if you look down the coil, it turns in a clockwise direction as if spiralling away from you. It becomes a αhelix structure because the chain collapses round on itself due to hydrogen bonding.
The hydrogen bonds form between the C=O and the N-H at every turn because hydrogen, when bonded with a highly electronegative atom such as nitrogen experiences attraction to other nearby highly electronegative atoms, such as oxygen.
Hydrophobic groups cluster together at the centre of the molecule away from any water, this makes them soluble.
The tertiary structure of a protein takes form when the αhelix folds over on itself giving the protein it’s unique three dimensional shape. The secondary structure can fold over itself because of the hydrocarbon side groups represented by “R” in the diagram under “What are proteins?”. These can form ionic or hydrogen bonds with each other