A Proteins shape depends on four levels of Structure

The four levels of Structure are the primary structure of a protein which is its unique sequence of amino acids. The primary structure of a protein is determined by inherited genetic information. Even a slight change in a protein's primary structure may affect its ability to function. The second level of the protein structure are parts of the polypeptide coil or fold into local patterns called a secondary structure. Tertiary structure refers to the overall three-dimensional shape of a polypeptide. Most tertiary structures can be roughly described as either globular or fibrous. Many proteins consist of two or more polypeptide chains, or subunits. Such proteins have a quaternary structure, resulting from the association of the subunits.








   

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