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:
e1pkpA2[A:78-148] nonrep Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
RIBOSOMAL PROTEIN S5 ; X-RAY DIFFRACTION
e4v6iAE3[AE:176-254] nonrep Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
40S ribosomal protein rpS2 (S5p) ; ELECTRON MICROSCOPY
e8c83R3[R:176-249] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
40S ribosomal protein S2 ; ELECTRON MICROSCOPY
e8cahR2[R:176-249] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
40S ribosomal protein S2 ; ligands: MG ; ELECTRON MICROSCOPY
e8casR1[R:176-249] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
40S ribosomal protein S2 ; ELECTRON MICROSCOPY
e8cbjC3[C:176-250] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
40S ribosomal protein S2 ; ELECTRON MICROSCOPY
e8q5iD2[D:171-244] Image Pymol Jmol Links: PDB, SCOP, CATHDOI
; ELECTRON MICROSCOPY
e8p5dSC01[SC0:168-248] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
; ELECTRON MICROSCOPY
e8auvc1[c:186-259] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
uS5 (40S ribosomal protein S2) ; ELECTRON MICROSCOPY
e8b2lc12[c1:186-259] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
40S ribosomal protein S2-3-like ; ELECTRON MICROSCOPY
e8t4sC3[C:202-276] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
; ligands: MG ; ELECTRON MICROSCOPY
e8ppkC2[C:202-278] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
40S ribosomal protein S2 ; ELECTRON MICROSCOPY
e8p2kAb1[Ab:202-276] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
40S ribosomal protein S2 ; ELECTRON MICROSCOPY
e8bhfD31[D3:202-278] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
; ELECTRON MICROSCOPY
e8a98SF3[SF:188-263] Image Pymol Jmol Links: PDB, SCOP, CATH
40S ribosomal protein S2 ; ELECTRON MICROSCOPY
e8eubBC1[BC:176-250] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
; ELECTRON MICROSCOPY
e8ccsf2[f:176-250] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
40S ribosomal protein S2 ; ELECTRON MICROSCOPY
PreviousPseudo 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