List of proteins

List of proteins
Proteins are a class of macromolecular organic compounds that are essential to life. They consist of a long polypeptide chain that usually adopts a single stable three-dimensional structure. They fulfill a wide variety of functions including providing structural stability to cells, catalyze chemical reactions that produce or store energy or synthesize other biomolecules including nucleic acids and proteins, transport essential nutrients, or serve other roles such as signal transduction. They are selectively transported to various compartments of the cell or in some cases, secreted from the cell.
This list aims to organize information on how proteins are most often classified: by structure, by function, or by location.
Structure
Proteins may be classified as to their three-dimensional structure (also known a protein fold). The two most widely used classification schemes are:
CATH database
Structural Classification of Proteins database (SCOP)
Both classification schemes are based on a hierarchy of fold types. At the top level are all alpha proteins (domains consisting of alpha helices), all beta proteins (domains consisting of beta sheets), and mixed alpha helix/beta sheet proteins.
While most proteins adopt a single stable fold, a few proteins can rapidly interconvert between one or more folds. These are referred to as metamorphic proteins. Finally other proteins appear not to adopt any stable conformation and are referred to as intrinsically disordered.
Proteins frequently contain two or more domains, each have a different fold separated by intrinsically disordered regions. These are referred to as multi-domain proteins.
Function
Proteins may also be classified based on their celluar function. A widely used classification is PANTHER (protein analysis through evolutionary relationships) classification system.
Structural
Protein#Structural proteins
Catalytic
Enzymes classified according to their Enzyme Commission number (EC). Note that strictly speaking, an EC number corresponds to the reaction the enzyme catalyzes, not the protein per se. However each EC number has been mapped to one or more specific proteins.
List of enzymes
EC 1: Oxidoreductases
EC 2: Transferases
EC 3: Hydrolases
EC 4: Lyases
EC 5: Isomerases
EC 6: Ligases
EC 7: Translocases
Transport
Transport protein
Ion channel
Solute carrier family
Immune
Antibody
Chemokines and their receptors
Cytokines and their receptors
Pattern recognition receptors
Genetic
DNA/RNA synthesis
DNA repair
replication
transcription (Transcription factor, transcriptional coregulator)
Signal transduction
Signal transduction
Sub-cellular distribution
Proteins may also be classified by which subcellular compartment they are found.
Nuclear
Nuclear proteins
Cytosolic
Cytosolic proteins
Cytoskeletal
Cytoskeletal proteins
Organelle
Endoplasmic reticulum
Endoplasmic reticulum resident protein
Lysosomal
Mitochondial
Mitochondrial DNA that encode mitochondial proteins (note that some mitochondial proteins are encoded by nuclear DNA)
Chloroplast
Chloroplast DNA that encode chloroplast proteins
Cell membrane
Membrane protein
Integral membrane protein
Peripheral membrane protein
Extracellular matrix
Extracellular matrix proteins
Plasma
Blood protein
Species distribution
Mammalian
Vertebrate
Plant
Bacterial proteins
Archaeal proteins
Viral proteins
References
Protein
Protein classification