In molecular biology, binding domain is a protein domain which binds to a specific atom or molecule, such as calcium or DNA. A protein domain is a part of a protein sequence and a tertiary structure that can change or evolve, function, and live by itself independent of the rest of the protein chain.[1] Upon binding, proteins may undergo a conformational change. Binding domains are essential for the function of many proteins. They are essential because they help splice, assemble, and translate proteins.[2]
Examples of binding domains include the Zinc finger, which binds to DNA, and EF hand, which binds to calcium.