The sequence of amino acids in the polypeptide chain.
Secondary structure
Most basic level of protein folding
Its held together by hydrogen bonds between carboxyl groups and amino group
2 most common area-helixand theb-sheet
a-helix
a-helix is wound and coiled to form a helix, and it is held together by hydrogen bonds, there are many hydrogen bonds so its a very stable and strong structure.
b-sheet
The polypeptide chain zig-zags forming sheet of anti-parralel strands.and is also held together by hydrogen bonds.
1 of 2
Tertiary & Quartenary stucture
Tertiary structure
The compact and 3D globular structure formed from bending and twisting of the polypeptide helix into a compact structure. The shape is mantained by ionic, disulphide and hydrogen bonds.
Quaternary Structure
Combination of two or more polypeptide chains in tertiary form. e.g Haemoglobin is made of 4 globular sub-units arranged in pyramid structure. Each sub-unit contains one atom of iron which can bind to on molecule of oxygen.
Comments
No comments have yet been made