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: Formyltransferase
H: Formyltransferase
T: Formyltransferase
F: Formyl_trans_N
Representatives:
e2blnA2[A:1-203]
nonrep
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PROTEIN YFBG ; ligands: ACT,FON,U5P ; X-RAY DIFFRACTION 1.2Å
e1jkxA1[A:1-209]
nonrep
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Pymol
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PHOSPHORIBOSYLGLYCINAMIDE FORMYLTRANSFERASE ; ligands: 138 ; X-RAY DIFFRACTION 1.60Å
e2bw0A2[A:1-203]
nonrep
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10-FORMYLTETRAHYDROFOLATE DEHYDROGENASE ; ligands: SO4 ; X-RAY DIFFRACTION 1.7Å
e1meoA1[A:1-205]
nonrep
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Phosphoribosylglycinamide formyltransferase ; ligands: PO4,SO4 ; X-RAY DIFFRACTION 1.72Å
e1zghA2[A:1-164]
nonrep
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Pymol
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Methionyl-tRNA formyltransferase ; ligands: UNX ; X-RAY DIFFRACTION 1.98Å
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