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
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
![](/ecod/img/m.gif)
binds one zinc with two CxxC motifs on two beta-hairpins
![](/ecod/img/m.gif)
![](/ecod/img/m.gif)
![](/ecod/img/m.gif)
Representatives:
e3k7aM1[M:17-66]
nonrep
Image
Pymol
Jmol Links:
PDB,
SCOP,
CATH, PubMed,
DOI
TRANSCRIPTION INITIATION FACTOR IIB ; ligands: ZN ; X-RAY DIFFRACTION 3.8Å
e1dl6A1[A:2-59]
nonrep
Image
Pymol
Jmol Links:
PDB,
SCOP,
CATH, PubMed,
TRANSCRIPTION FACTOR II B (TFIIB) ; ligands: ZN ; SOLUTION NMR
e1pftA1[A:1-50]
nonrep
Image
Pymol
Jmol Links:
PDB,
SCOP,
CATH, PubMed,
DOI
TFIIB ; ligands: ZN ; SOLUTION NMR
e1rlyA1[A:2-59] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; SOLUTION NMR
e5fmfR2[R:119-160] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
TRANSCRIPTION INITIATION FACTOR IIE SUBUNIT ALPHA, TFA1 ; ELECTRON MICROSCOPY
e5svah1[h:119-160] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIE subunit alpha ; ELECTRON MICROSCOPY
e1ro4A1[A:2-59] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; SOLUTION NMR
e6gylW1[W:100-169] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIE subunit alpha,Tfa1,Tfa1 ; ligands: ZN ; ELECTRON MICROSCOPY
e4v1oM3[M:22-68] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
TRANSCRIPTION INITIATION FACTOR IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e7ml0W1[W:100-169] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIE subunit alpha ; ligands: ZN ; ELECTRON MICROSCOPY
e5fmfP3[P:17-68] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
TRANSCRIPTION INITIATION FACTOR IIB, SUA7 ; ELECTRON MICROSCOPY
e5iy7M1[M:7-67] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e7ml1W2[W:100-169] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIE subunit alpha ; ligands: ZN ; ELECTRON MICROSCOPY
e7ml2W2[W:100-169] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIE subunit alpha ; ligands: ZN ; ELECTRON MICROSCOPY
e5iy8M1[M:7-67] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e5iy9M3[M:7-67] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e7ml4W2[W:100-169] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIE subunit alpha ; ligands: ZN ; ELECTRON MICROSCOPY
e5iybM1[M:7-67] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e5iycM1[M:7-67] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e5iydM1[M:7-67] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e5iy7Q1[Q:104-204] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
General transcription factor IIE subunit 1 ; ligands: ZN ; ELECTRON MICROSCOPY
e5iy9Q1[Q:104-204] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
General transcription factor IIE subunit 1 ; ligands: ZN ; ELECTRON MICROSCOPY
e5iybQ1[Q:104-204] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
General transcription factor IIE subunit 1 ; ligands: ZN ; ELECTRON MICROSCOPY
e5iydQ2[Q:104-204] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
General transcription factor IIE subunit 1 ; ligands: ZN ; ELECTRON MICROSCOPY
e5gpyA2[A:104-196] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
General transcription factor IIE subunit 1 ; ligands: ZN ; X-RAY DIFFRACTION 2.10Å
e5oqjM1[M:16-68] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e5oqmM1[M:16-68] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e6gykM3[M:16-68] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e6gylM1[M:16-68] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e6gymM3[M:16-68] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e6o9lM1[M:7-67] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e7lbmO3[O:7-54] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e7lbmQ1[Q:104-201] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
General transcription factor IIE subunit 1 ; ligands: ZN ; ELECTRON MICROSCOPY
e7edxR1[R:13-49] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e7eg7R3[R:13-49] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e7eg8R2[R:13-51] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e7eg9R2[R:13-49] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e7egaR2[R:13-51] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e7egbR1[R:13-50] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e7nvrM3[M:14-54] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e7nvsM3[M:14-54] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e7nvtM2[M:14-54] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e7nvyM1[M:14-54] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e7nvzM3[M:14-54] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e7eg9U1[U:101-174] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
General transcription factor IIE subunit 1 ; ligands: ZN ; ELECTRON MICROSCOPY
e7egaU2[U:101-174] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
General transcription factor IIE subunit 1 ; ligands: ZN ; ELECTRON MICROSCOPY
e7egbU1[U:101-174] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
General transcription factor IIE subunit 1 ; ligands: ZN ; ELECTRON MICROSCOPY
e7nvuM2[M:14-67] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e7nw0M3[M:14-67] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e7nvrW1[W:104-196,W:274-288] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
General transcription factor IIE subunit 1 ; ligands: ZN ; ELECTRON MICROSCOPY
e7nvsW1[W:104-196] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
General transcription factor IIE subunit 1 ; ligands: ZN ; ELECTRON MICROSCOPY
e7nvtW1[W:104-196] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
General transcription factor IIE subunit 1 ; ligands: ZN ; ELECTRON MICROSCOPY
e7nvuW1[W:104-196] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
General transcription factor IIE subunit 1 ; ligands: ZN ; ELECTRON MICROSCOPY
e7nvyW1[W:104-196,W:274-288] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
General transcription factor IIE subunit 1 ; ligands: ZN ; ELECTRON MICROSCOPY
e7nvzW2[W:104-196,W:274-288] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
General transcription factor IIE subunit 1 ; ligands: ZN ; ELECTRON MICROSCOPY
e7nw0W1[W:104-196,W:274-288] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
General transcription factor IIE subunit 1 ; ligands: ZN ; ELECTRON MICROSCOPY
e7egcR2[R:13-50] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e7enaBA3[BA:11-53] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e7o4iM2[M:14-58] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e7o72M3[M:14-68] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e7egcU1[U:101-174] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
General transcription factor IIE subunit 1 ; ligands: ZN ; ELECTRON MICROSCOPY
e7enaEA2[EA:101-174] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
General transcription factor IIE subunit 1 ; ligands: ZN ; ELECTRON MICROSCOPY
e7encBA1[BA:13-51] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e7o4jM2[M:14-58] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e7o73M3[M:14-58] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e7o75M3[M:14-58] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e7encEA1[EA:104-203] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
General transcription factor IIE subunit 1 ; ligands: ZN ; ELECTRON MICROSCOPY
e7ml4M3[M:22-58,M:124-127] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e7ml0M3[M:16-68] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e7ml1M3[M:16-68] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e7ml2M2[M:16-68] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e8gxqBA1[BA:14-54] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e8gxsBA1[BA:14-54] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e7zwdM2[M:14-54] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e7zx7M3[M:14-54] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e7ui9M1[M:21-55] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ELECTRON MICROSCOPY
e7uifM1[M:21-55] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ELECTRON MICROSCOPY
e7uioAM1[AM:21-55] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ELECTRON MICROSCOPY
e7uioBM1[BM:21-55] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ELECTRON MICROSCOPY
e8ceoM2[M:14-58] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e7zs9M3[M:14-58] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e7zsaM1[M:14-58] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e7zsbM2[M:14-58] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e7zx8M2[M:14-67] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e8gxqEA2[EA:104-196] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
General transcription factor IIE subunit 1 ; ligands: ZN ; ELECTRON MICROSCOPY
e8gxsEA1[EA:104-196] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
General transcription factor IIE subunit 1 ; ligands: ZN ; ELECTRON MICROSCOPY
e8bvwM2[M:14-54] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e8byqM1[M:14-54] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e8bz1M3[M:14-54] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e8cenM3[M:14-58] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription initiation factor IIB ; ligands: ZN ; ELECTRON MICROSCOPY
e8bvwW1[W:104-196,W:274-288] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
General transcription factor IIE subunit 1 ; ligands: ZN ; ELECTRON MICROSCOPY
e8byqW1[W:104-196] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
General transcription factor IIE subunit 1 ; ligands: ZN ; ELECTRON MICROSCOPY
e6cncR1[R:1-41] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription factor IIIB 70 kDa subunit,TATA-box-binding protein,Transcription factor IIIB 70 kDa subunit ; ligands: ZN ; ELECTRON MICROSCOPY
e6cndR2[R:1-41] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription factor IIIB 70 kDa subunit,TATA-box-binding protein,Transcription factor IIIB 70 kDa subunit ; ligands: ZN ; ELECTRON MICROSCOPY
e6cnfR2[R:1-41] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcription factor IIIB 70 kDa subunit,TATA-box-binding protein,Transcription factor IIIB 70 kDa subunit ; ligands: ZN ; 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.
![](/ecod/img/p.gif)
binds two zincs. one in the same way as rubredoxin, probably related to rubredoxin. the other in a similar way as glucocorticoid receptor
extended segmentsextended, non-globular segments, frequently bind to other proteins to form complexes