Binding domain
Encyclopedia
A binding domain is a protein domain
which binds
to a specific atom or molecule, such as calcium
or DNA
. Upon binding, proteins may undergo a conformational change
. Binding domains are essential for the function of many proteins.
Examples of binding domains include Zinc finger
, which binds to DNA, and EF hand
, which binds to calcium.
Protein domain
A protein domain is a part of protein sequence and structure that can evolve, function, and exist independently of the rest of the protein chain. Each domain forms a compact three-dimensional structure and often can be independently stable and folded. Many proteins consist of several structural...
which binds
Binding (molecular)
Molecular binding is an attractive interaction between two molecules which results in a stable association in which the molecules are in close proximity to each other...
to a specific atom or molecule, such as calcium
Calcium
Calcium is the chemical element with the symbol Ca and atomic number 20. It has an atomic mass of 40.078 amu. Calcium is a soft gray alkaline earth metal, and is the fifth-most-abundant element by mass in the Earth's crust...
or DNA
DNA
Deoxyribonucleic acid is a nucleic acid that contains the genetic instructions used in the development and functioning of all known living organisms . The DNA segments that carry this genetic information are called genes, but other DNA sequences have structural purposes, or are involved in...
. Upon binding, proteins may undergo a conformational change
Conformational change
A macromolecule is usually flexible and dynamic. It can change its shape in response to changes in its environment or other factors; each possible shape is called a conformation, and a transition between them is called a conformational change...
. Binding domains are essential for the function of many proteins.
Examples of binding domains include Zinc finger
Zinc finger
Zinc fingers are small protein structural motifs that can coordinate one or more zinc ions to help stabilize their folds. They can be classified into several different structural families and typically function as interaction modules that bind DNA, RNA, proteins, or small molecules...
, which binds to DNA, and EF hand
EF hand
The EF hand is a helix-loop-helix structural domain found in a large family of calcium-binding proteins. The EF-hand motif contains a helix-loop-helix topology, much like the spread thumb and forefinger of the human hand, in which the Ca2+ ions are coordinated by ligands within the loop...
, which binds to calcium.