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
![](/ecod/img/m.gif)
![](/ecod/img/p.gif)
![](/ecod/img/p.gif)
![](/ecod/img/m.gif)
Representatives:
e1twfA3[A:1142-1272]
nonrep
Image
Pymol
Jmol Links:
PDB,
SCOP,
CATH, PubMed,
DOI
DNA-DIRECTED RNA POLYMERASE II LARGEST SUBUNIT ; X-RAY DIFFRACTION 2.3Å
e7egao8[o:1165-1297] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase subunit ; ELECTRON MICROSCOPY
e7egbo4[o:1165-1297] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase II subunit RPB1 ; ELECTRON MICROSCOPY
e7nvrA9[A:1165-1297] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase subunit ; ELECTRON MICROSCOPY
e7nvsA2[A:1165-1297] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
RPB1 ; ELECTRON MICROSCOPY
e7nvtA4[A:1165-1297] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
RPB1 ; ELECTRON MICROSCOPY
e7nvuA5[A:1165-1297] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
RPB1 ; ELECTRON MICROSCOPY
e7nvyA4[A:1165-1297] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
RPB1 ; ELECTRON MICROSCOPY
e7nvzA7[A:1165-1297] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
RPB1 ; ELECTRON MICROSCOPY
e7nw0A9[A:1165-1297] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
RPB1 ; ELECTRON MICROSCOPY
e6xreA4[A:1165-1297] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase II subunit RPB1 ; ELECTRON MICROSCOPY
e7kedA1[A:1132-1242] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase II subunit RPB1 ; X-RAY DIFFRACTION 3.550Å
e7o4iA2[A:1132-1242] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase II subunit RPB1 ; ELECTRON MICROSCOPY
e7egco5[o:1165-1297] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase II subunit RPB1 ; ELECTRON MICROSCOPY
e7b7uA4[A:1152-1308] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase subunit ; ELECTRON MICROSCOPY
e7nkyA3[A:1132-1242] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase II subunit RPB1 ; ELECTRON MICROSCOPY
e7keeA3[A:1132-1242] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase II subunit RPB1 ; X-RAY DIFFRACTION 3.410Å
e7kefA7[A:1132-1242] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase II subunit RPB1 ; X-RAY DIFFRACTION 3.890Å
e7o4jA1[A:1132-1242] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase II subunit RPB1 ; ELECTRON MICROSCOPY
e7o72A6[A:1132-1242] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase II subunit RPB1 ; ELECTRON MICROSCOPY
e7o73A5[A:1132-1242] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase II subunit RPB1 ; ELECTRON MICROSCOPY
e7o75A9[A:1132-1242] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase II subunit RPB1 ; ELECTRON MICROSCOPY
e7f4gA6[A:1163-1299] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
RPB1 ; ELECTRON MICROSCOPY
e7okxA7[A:1165-1298] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase II subunit RPB1 ; ELECTRON MICROSCOPY
e7nkxA7[A:1142-1272] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase II subunit RPB1 ; ELECTRON MICROSCOPY
e6gmhA7[A:1165-1297] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
RPB1 ; ELECTRON MICROSCOPY
e7okyA7[A:1165-1298] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase II subunit RPB1 ; ELECTRON MICROSCOPY
e7ol0A7[A:1164-1299] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase II subunit RPB1 ; ELECTRON MICROSCOPY
e7oznA6[A:1165-1298] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
RPB1 ; ELECTRON MICROSCOPY
e7oznM6[M:1165-1298] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
RPB1 ; ELECTRON MICROSCOPY
e7ozoA6[A:1165-1298] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase subunit ; ELECTRON MICROSCOPY
e7ozoM6[M:1165-1298] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase subunit ; ELECTRON MICROSCOPY
e7ozpA6[A:1165-1296] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase subunit ; ELECTRON MICROSCOPY
e7ozpM6[M:1165-1296] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase subunit ; ELECTRON MICROSCOPY
e7pksA7[A:1164-1299] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase subunit ; ELECTRON MICROSCOPY
e7rimA3[A:1132-1242] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase II subunit RPB1 ; X-RAY DIFFRACTION 2.9Å
e7oobA7[A:1165-1297] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase II subunit RPB1 ; ELECTRON MICROSCOPY
e7ml0A3[A:1142-1272] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase subunit ; ELECTRON MICROSCOPY
e7ml1A4[A:1142-1272] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase subunit ; ELECTRON MICROSCOPY
e7ml2A4[A:1142-1272] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase subunit ; ELECTRON MICROSCOPY
e7ml4A1[A:1142-1272] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase subunit ; ELECTRON MICROSCOPY
e7ripA2[A:1142-1272] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase II subunit RPB1 ; X-RAY DIFFRACTION 3.270Å
e7riqA7[A:1142-1272] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase II subunit RPB1 ; X-RAY DIFFRACTION 2.960Å
e7riwA5[A:1142-1272] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase II subunit RPB1 ; X-RAY DIFFRACTION 3.17Å
e7rixA3[A:1142-1272] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase II subunit RPB1 ; X-RAY DIFFRACTION 3.3Å
e7riyA8[A:1142-1272] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase II subunit RPB1 ; X-RAY DIFFRACTION 3.630Å
e7oo3A4[A:1165-1297] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase II subunit RPB1 ; ELECTRON MICROSCOPY
e7oopA6[A:1165-1297] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase II subunit RPB1 ; ELECTRON MICROSCOPY
e7opcA6[A:1165-1297] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase II subunit RPB1 ; ELECTRON MICROSCOPY
e7opdA1[A:1165-1297] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase II subunit RPB1 ; ELECTRON MICROSCOPY
e7meia5[a:1132-1242] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase subunit ; ELECTRON MICROSCOPY
e7meiA7[A:1132-1242] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase subunit ; ELECTRON MICROSCOPY
e7mk9A1[A:1132-1242] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase subunit ; ELECTRON MICROSCOPY
e7mkaa3[a:1132-1242] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase subunit ; ELECTRON MICROSCOPY
e7xn7A9[A:1134-1244] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase subunit ; ELECTRON MICROSCOPY
e7xseA3[A:1134-1244] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase subunit ; ELECTRON MICROSCOPY
e7xsxA2[A:1134-1244] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase subunit ; ELECTRON MICROSCOPY
e7xszA4[A:1134-1244] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase subunit ; ELECTRON MICROSCOPY
e7xtdA1[A:1134-1244] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase subunit ; ELECTRON MICROSCOPY
e7xt7A1[A:1134-1244] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase subunit ; ELECTRON MICROSCOPY
e7xtiA1[A:1134-1244] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase subunit ; ELECTRON MICROSCOPY
e7ui9A5[A:1132-1242] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase II subunit RPB1 ; ELECTRON MICROSCOPY
e7uifA1[A:1132-1242] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase II subunit RPB1 ; ELECTRON MICROSCOPY
e7uioAA3[AA:1132-1242] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase II subunit RPB1 ; ELECTRON MICROSCOPY
e7uioBA5[BA:1132-1242] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase II subunit RPB1 ; ELECTRON MICROSCOPY
e7zs9A6[A:1132-1242] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase II subunit RPB1 ; ELECTRON MICROSCOPY
e7zsaA2[A:1132-1242] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase II subunit RPB1 ; ELECTRON MICROSCOPY
e7zsbA2[A:1132-1242] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase II subunit RPB1 ; ELECTRON MICROSCOPY
e7zwdA7[A:1165-1297] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase subunit ; ELECTRON MICROSCOPY
e7zx7A2[A:1165-1297] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase subunit ; ELECTRON MICROSCOPY
e7zx8A1[A:1165-1297] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase subunit ; ELECTRON MICROSCOPY
e8h0vA3[A:1134-1244] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase subunit ; ELECTRON MICROSCOPY
e8h0wA2[A:1134-1244] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase subunit ; ELECTRON MICROSCOPY
e8bvwA7[A:1165-1297] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase subunit ; ELECTRON MICROSCOPY
e8byqA6[A:1165-1297] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase subunit ; ELECTRON MICROSCOPY
e8bz1A3[A:1165-1297] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase subunit ; ELECTRON MICROSCOPY
e7ycx18[1:1165-1297] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
DNA-directed RNA polymerase II subunit RPB1,DNA-directed RNA polymerase II subunit RPB1, CTD1, CTD2, CTD3, CTD4 ; ELECTRON MICROSCOPY
e8p4fA1[A:1165-1297] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
; ELECTRON MICROSCOPY
e8a40A9[A:1165-1297] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
; ligands: ZN ; ELECTRON MICROSCOPY
e8b3dA8[A:1165-1297] Image Pymol Jmol Links: PDB, SCOP, CATH
; ELECTRON MICROSCOPY
e8oeuA9[A:1165-1297] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
; ELECTRON MICROSCOPY
e8p4aA1[A:1165-1297] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
; ELECTRON MICROSCOPY
e7wbvA4[A:1134-1244] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
; ELECTRON MICROSCOPY
Previous![](/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.
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