Evolutionary classification of protein domain structures
alpha arraysalpha-helix arrays with mainly perpendicular helices
alpha bundlesalpha-helix bundles with mainly parallel helices
alpha superhelicesrepeating alpha-helix hairpins form a superhelix
alpha duplicates or obligate multimersalpha duplicates or monomers associate together to form a compact domain
alpha complex topologyalpha domain with complex and unique topology that cannot be described as array or bundle or superhelix
beta barrelssingle beta-sheet folded upon itself to form a barrel
beta meanderssingle beta-sheet with mainly meander topology
beta sandwichestwo beta-sheets stacked together to form a sandwich
beta duplicates or obligate multimersbeta duplicates or monomers associate together to form a compact domain
beta complex topologybeta domains with complex and unique topology that cannot be described as barrel or sandwich or meander
a+b two layersone alpha-helix layer and one beta-sheet layer
looks like an elaborated ferredoxin
contains a HTH motif
Representatives:
e3ssmA1[A:6-160] nonrep Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyltransferase ; X-RAY DIFFRACTION 2.247Å
e8ia9A1[A:4-157] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
; X-RAY DIFFRACTION 2.50Å
e8iaaB1[B:4-157] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
; X-RAY DIFFRACTION 2.10Å
e8iaaA2[A:4-157] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
; X-RAY DIFFRACTION 2.10Å
e3ssmB2[B:6-165] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyltransferase ; X-RAY DIFFRACTION 2.247Å
e3ssmD1[D:5-162] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyltransferase ; X-RAY DIFFRACTION 2.247Å
e3ssnA1[A:6-162] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyltransferase ; ligands: DMS,MVI ; X-RAY DIFFRACTION 2.392Å
e3ssnB2[B:6-165] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyltransferase ; X-RAY DIFFRACTION 2.392Å
e3ssnD1[D:5-162] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyltransferase ; ligands: GOL ; X-RAY DIFFRACTION 2.392Å
e3ssoA1[A:6-162] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyltransferase ; X-RAY DIFFRACTION 1.895Å
e3ssoB1[B:6-162] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyltransferase ; X-RAY DIFFRACTION 1.895Å
e3ssoC1[C:6-162] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyltransferase ; X-RAY DIFFRACTION 1.895Å
e3ssoD1[D:6-162] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyltransferase ; X-RAY DIFFRACTION 1.895Å
e3ssoE1[E:6-162] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyltransferase ; X-RAY DIFFRACTION 1.895Å
e3ssoF1[F:6-162] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyltransferase ; X-RAY DIFFRACTION 1.895Å
e3ssnC1[C:6-162] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyltransferase ; ligands: DMS,MVI ; X-RAY DIFFRACTION 2.392Å
e8ia9B2[B:3-157] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
; X-RAY DIFFRACTION 2.50Å
e3ssmC1[C:-19-135] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyltransferase ; X-RAY DIFFRACTION 2.247Å
Pseudo group of domains that do not map to PFam family profiles. Domains inside should not be considered as in one family.
a+b three layersone mainly antiparallel beta-sheet layer sandwiched between two alpha-helix layers
a+b four layerstwo beta-sheet layers sandwiched between two alpha-helix layers
a+b complex topologyalpha and beta domain with complex and unique topology that cannot be described in layers
a+b duplicates or obligate multimersalpha and beta duplicates or monomers associated together to form a compact domain
a/b barrelsrepeating beta-alpha units form a barrel
a/b three-layered sandwichesrepeating beta-alpha units form a sandwich with a mainly parallel beta-sheet layer stacked between two alpha-helix layers
mixed a+b and a/balpha and beta domain consists of both a+b and a/b regions
few secondary structure elementsstabilized by cofactors or disulfides
extended segmentsextended, non-globular segments, frequently bind to other proteins to form complexes