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Enzymes have four levels of structures These are:

• Primary structure *
• Secondary structure *
• Tertiary structure *
• Quaternary structure

The enzyme structure ranges from a basic amino acid sequence to a three dimensional (3D) structure in a folded protein.Primary structure Enzymes are made up of amino acids which are linked together via amide (peptide) bonds in a linear chain.The amino acid sequence in polypeptide chains in each enzyme is distinct and determines the three-dimensional shape.This ?is its tertiary structure

?quaternary structure Sometimes, proteins or functional enzymes can be made up of more than one polypeptide chains, which are known as subunits.The hydrogen in the amino group (NH2) and the oxygen in the carboxyl group (COOH) of each amino acid can bond with each other by means of hydrogen bond, this means that the amino acids in the same chain can interact with each other.?Secondary structure ?

Enzymes have four levels of structures These are:

• Primary structure *


• ⁠Secondary structure *


• ⁠Tertiary structure *


• ⁠Quaternary structure

The enzyme structure ranges from a basic amino acid sequence to a three dimensional (3D) structure in a folded protein. The amino acid sequence in polypeptide chains in each enzyme is distinct and determines the three-dimensional shape. Further, it is the 3D structure of an enzyme that determines the enzyme activities.

Primary structure
Enzymes are made up of amino acids which are linked together via amide (peptide) bonds in a linear chain. This is the primary structure. The resulting amino acid chain is called a polypeptide or protein. The specific order of amino acid in the protein is encoded by the DNA sequence of the corresponding gene.

‏Secondary structure ‏
The hydrogen in the amino group (NH2) and the oxygen in the carboxyl group (COOH) of each amino acid can bond with each other by means of hydrogen bond, this means that the amino acids in the same chain can interact with each other. As a result, the protein chain can fold up on itself, and it can fold up in two ways, resulting in two secondary structures: it can either wrap round forming the α-helix, or it can fold on top of itself forming the β-sheet.

‏Tertiary structure ‏
As a consequence of the folding-up of the 2D linear chain in the secondary structure, the protein can fold up further and in doing so gains a three-dimensional structure. This ‏is its tertiary structure

‏quaternary structure Sometimes, proteins or functional enzymes can be made up of more than one polypeptide chains, which are known as subunits. The interaction between these subunits is called the quaternary structure. Various interactions, including H-bonding, disulfide-bridges and salt bridges are also involved in stabilizing the overall complex