Supersecondary protein structure refers to the arrangement of multiple secondary structure elements within a region of a protein chain, forming a distinct and recurring spatial arrangement. While secondary structure elements, such as α-helices and β-sheets, describe the local folding of the protein backbone, supersecondary structure defines the arrangement of these elements relative to each other on a larger scale. It can also be referred to as a motif or a fold.
Supersecondary structures are typically stabilized by various interactions, including hydrogen bonding, van der Waals forces, and hydrophobic interactions, among others. Different arrangements of secondary structure elements give rise to a wide range of supersecondary structures, each with its unique functions and properties.
Examples of supersecondary structures include α-β motifs, β-α-β motifs, β-meanders, α-helical hairpins, and much more. These structural motifs often play critical roles in protein folding, stability, and function. They are frequently involved in protein-protein interactions, enzymatic activities, ligand binding, and signal transduction processes.
The determination and analysis of supersecondary structures greatly contribute to the understanding of protein structure and function on a molecular level. By identifying and characterizing these distinct structural arrangements, researchers are able to gain insights into the mechanisms underlying protein folding, stability, and interaction, as well as to design and engineer proteins with desired functions or properties.
