quaternary structure

Quaternary structure refers to how multiple protein chains, or subunits, come together to form a functional protein complex. Think of it like individual building blocks assembling to create a larger, more complex structure with specific functions. This arrangement is stabilized by various interactions such as hydrogen bonds, ionic bonds, and hydrophobic effects. Quaternary structures are essential for the activity of many proteins, like hemoglobin, which uses multiple subunits to efficiently transport oxygen in the blood. Overall, it represents the way protein subunits organize and interact to achieve their biological roles.