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: HAD domain-like
H: HAD domain-related
T: DHH phosphoesterases
F: DHH
Representatives:
e1wpnA1[A:2-188]
nonrep
Image
Pymol
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Manganese-dependent inorganic pyrophosphatase ; ligands: MN,SO4 ; X-RAY DIFFRACTION 1.3Å
e1k20A2[A:2-192]
nonrep
Image
Pymol
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MANGANESE-DEPENDENT INORGANIC PYROPHOSPHATASE ; ligands: GOL,MN,SO4 ; X-RAY DIFFRACTION 1.5Å
e4py9A1[A:2-215]
nonrep
Image
Pymol
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CATH
PUTATIVE EXOPOLYPHOSPHATASE-RELATED PROTEIN ; ligands: NA,PO4 ; X-RAY DIFFRACTION 2.25Å
e2zxoA1[A:1-310]
nonrep
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Pymol
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SINGLE-STRANDED DNA SPECIFIC EXONUCLEASE RECJ ; X-RAY DIFFRACTION 2.5Å
e5f55A1[A:1-313]
nonrep
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Pymol
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Single-stranded-DNA-specific exonuclease ; ligands: MN,SO4 ; X-RAY DIFFRACTION 2.600Å
e5ghtA1[A:1-194,A:279-338]
nonrep
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Pymol
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SsDNA-specific exonuclease ; X-RAY DIFFRACTION 2.795Å
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