::Protein domain


Journal::protein    Domains::title    Domain::pages    Volume::author    Issue::proteins    Protein::first

Pyruvate kinase, a protein with three domains (PDB: 1PKN​).

A protein domain is a conserved part of a given protein sequence and (tertiary) 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 domains. One domain may appear in a variety of different proteins. Molecular evolution uses domains as building blocks and these may be recombined in different arrangements to create proteins with different functions. Domains vary in length from between about 25 amino acids up to 500 amino acids in length. The shortest domains such as zinc fingers are stabilized by metal ions or disulfide bridges. Domains often form functional units, such as the calcium-binding EF hand domain of calmodulin. Because they are independently stable, domains can be "swapped" by genetic engineering between one protein and another to make chimeric proteins.

Protein domain sections
Intro  Background  Domains are units of protein structure  Domains as evolutionary modules  Multidomain proteins   Domains are autonomous folding units    Domains and protein flexibility    Domain definition from structural co-ordinates    Domains of unknown function   See also  References   Key papers    External links   

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