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
X: P-loop domains-like
H: P-loop domains-related
T: P-loop containing nucleoside triphosphate hydrolases
F: AAA
Representatives:
e1d2nA3[A:505-675]
nonrep
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N-ETHYLMALEIMIDE-SENSITIVE FUSION PROTEIN ; ligands: ANP,MG ; X-RAY DIFFRACTION 1.75Å
e1jbkA1[A:157-351]
nonrep
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CLPB PROTEIN ; ligands: MG ; X-RAY DIFFRACTION 1.8Å
e4xguD2[D:122-321]
nonrep
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Pymol
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Putative pachytene checkpoint protein 2 ; ligands: SO4 ; X-RAY DIFFRACTION 2.29Å
e1iqpA3[A:2-169]
nonrep
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RFCS ; ligands: ADP ; X-RAY DIFFRACTION 2.8Å
e1sxjA3[A:295-478]
nonrep
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Activator 1 95 kDa subunit ; ligands: AGS,MG ; X-RAY DIFFRACTION 2.85Å
e1s3sB2[B:201-371]
nonrep
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TRANSITIONAL ENDOPLASMIC RETICULUM ATPASE (TER ATPASE) (15S MG(2+)- ATPASE P97 SUBUNIT) (VALOSIN CONTAINING PROTEIN) (VCP) [CONTAINS: VALOSIN] ; ligands: ADP ; X-RAY DIFFRACTION 2.9Å
e1qvrC4[C:149-271,C:291-330]
nonrep
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ClpB protein ; ligands: ANP,PT ; X-RAY DIFFRACTION 3.0Å
e5vq9D2[D:119-320]
nonrep
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Pachytene checkpoint protein 2 homolog ; X-RAY DIFFRACTION 3.02Å
e5kzfJ3[J:141-342]
nonrep
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Proteasome-associated ATPase ; X-RAY DIFFRACTION 3.49Å
e4ciuA1[A:159-339]
nonrep
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CHAPERONE PROTEIN CLPB ; ligands: ADP ; X-RAY DIFFRACTION 3.50Å
e1r7rA6[A:471-648]
nonrep
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Transitional endoplasmic reticulum ATPase ; X-RAY DIFFRACTION 3.6Å
e1lv7A2[A:144-324]
nonrep
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FtsH ; ligands: SO4 ; X-RAY DIFFRACTION
F: Unmapped domains
Pseudo group of domains that do not map to PFam family profiles. Domains inside should not be considered as in one family.
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