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: HUP domain-like
H: HUP domains
T: HUP domains
F: tRNA-synt_1
Representatives:
e1h3nA3[A:1-148,A:497-575]
nonrep
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LEUCYL-TRNA SYNTHETASE ; ligands: LEU,LMS ; X-RAY DIFFRACTION 2.0Å
e3ziuA1[A:1-151,A:319-402]
nonrep
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Pymol
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LEUCYL-TRNA SYNTHETASE ; ligands: GOL,LSS ; X-RAY DIFFRACTION 2.07Å
e1ffyA6[A:1-175,A:524-585]
nonrep
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ISOLEUCYL-TRNA SYNTHETASE ; ligands: MRC ; X-RAY DIFFRACTION 2.2Å
e3zjtA6[A:1-148,A:491-566]
nonrep
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LEUCYL-TRNA SYNTHETASE ; X-RAY DIFFRACTION 2.2Å
e1ileA3[A:1-170,A:515-583]
nonrep
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ISOLEUCYL-TRNA SYNTHETASE ; X-RAY DIFFRACTION 2.5Å
e4aq7A1[A:1-147,A:490-568]
nonrep
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LEUCINE--TRNA LIGASE ; ligands: LEU,LMS ; X-RAY DIFFRACTION 2.5Å
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