Tertiary Structure

Notes:

Tertiary structure is a protein structure that is formed by stabilizing forces such as Van der Wahls forces, as well as Hydrogen bonds, Ionic Bonds, and Disulfide bonds. These allow the protein to fold complexly and generate different domains and motifs. 

A domain is an independently folded and stable unit within a protein. These domains are often associated with a particular function. 

• They are typically 20-350 base pairs long. 

• They can ecist and fold stabily on their own. 

• Some molecules have multiple domains, which means they have multiple functions. For example, the SH2 domain or immunoglobulin. 

A motif is a small reoccuring structural pattern from a-helicies and beta sheets and is found inside of a domain. Multiple motifs come together to generate function! 

• Unlike a domain, motifs are not stable independently. 

Tertiarty structure allows scientisits to examine the concept of conservation. Domain "shuffling", or recombination, led to proteins being shuffled around but have still remained similar to each other. Domains are often also reused. These findings support the idea that domains are important and therefore conserved through evolution.