Proteins Flashcards
What monomers make up proteins?
Amino acids
What is the basic structure of an amino acid?
Amino group
Carboxyl group
R group (variable)
What is the primary structure of a protein?
Sequence of amino acids joined by peptide bonds between the amino and carboxyl groups
What bonds are found in the primary structure of a protein?
Peptide bonds
What is the secondary structure of a protein?
The arrangement of the polypeptide chain into an alpha helix or beta pleated sheet.
What is the general strucute of an alpha helix in the secondary structure of a protein?
Spiral coil with the peptide bonds forming the backbone and the R groups sticking out
What bonds are in the beta pleated sheet of the secondary structure?
Hydrogen bonds
How do hydrogen bonds form?
Small negative charge on the oxygen atom in the carboxyl group
Positive charge in the hydrogen atom of the amino group
What is the tertiary structure of a protein?
The alpha helixes and beta pleated sheets are folded into complex shapes with disulphide and ionic bonds
What bonds form in the tertiary structure?
Disulphide and ionic bonds
How do disulphide bonds form?
When two cysteine molocules are close together and an oxidation reaction occurs
How are ionic bonds formed?
Form between the strongly positive and negative amino acid side chains
What is quaternary structure?
Seperate polypeptide chains fit together in 3D
What conditions affect the bonds of a protein?
pH
Tempreture
What happens when a protein denatures?
Bonds break and the protein changes shape
