Evolutionary classification of protein domain structures
alpha arraysalpha-helix arrays with mainly perpendicular helices
![](/ecod/img/m.gif)
![](/ecod/img/m.gif)
![](/ecod/img/m.gif)
![](/ecod/img/m.gif)
Representatives:
e3bzkA4[A:564-636]
nonrep
Image
Pymol
Jmol Links:
PDB,
SCOP,
CATH, PubMed,
DOI
Tex ; X-RAY DIFFRACTION 2.30Å
e3psiA6[A:1002-1113]
nonrep
Image
Pymol
Jmol Links:
PDB,
SCOP,
CATH, PubMed,
DOI
TRANSCRIPTION ELONGATION FACTOR SPT6 ; X-RAY DIFFRACTION 3.3Å
e8oeuS6[S:1043-1144] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
; ELECTRON MICROSCOPY
e8of0S2[S:1043-1144] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
; ELECTRON MICROSCOPY
e3psfA4[A:1002-1114] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription elongation factor SPT6 ; X-RAY DIFFRACTION 2.59Å
e6gmhM3[M:1048-1144] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription elongation factor SPT6,Transcription elongation factor SPT6,Transcription elongation factor SPT6 ; ELECTRON MICROSCOPY
e6tedM7[M:1040-1144] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription elongation factor SPT6 ; ELECTRON MICROSCOPY
e7opcM2[M:1043-1144] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription elongation factor SPT6 ; ELECTRON MICROSCOPY
e7oopM5[M:1043-1144] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription elongation factor SPT6 ; ELECTRON MICROSCOPY
e7opdM6[M:1043-1144] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription elongation factor SPT6 ; ELECTRON MICROSCOPY
e7o6bA2[A:1002-1113] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription elongation factor SPT6 ; ELECTRON MICROSCOPY
e7uncM7[M:1040-1144] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription elongation factor SPT6 ; ELECTRON MICROSCOPY
e7undM8[M:1040-1144] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription elongation factor SPT6 ; ELECTRON MICROSCOPY
e8oevS4[S:1040-1144] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
; ELECTRON MICROSCOPY
![](/ecod/img/p.gif)
Pseudo group of domains that do not map to PFam family profiles. Domains inside should not be considered as in one family.
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
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