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: Thiamin diphosphate-binding fold (THDP-binding)
H: Thiamin diphosphate-binding fold (THDP-binding)
T: Thiamin diphosphate-binding fold (THDP-binding)
F: TPP_enzyme_N
Representatives:
e1q6zA2[A:2-181]
nonrep
Image
Pymol
Jmol Links:
PDB,
SCOP,
CATHDOI
Benzoylformate decarboxylase ; ligands: MG ; X-RAY DIFFRACTION 1.0Å
e2ez9A2[A:9-182]
nonrep
Image
Pymol
Jmol Links:
PDB,
SCOP,
CATH, PubMed,
DOI
Pyruvate oxidase ; ligands: FAD ; X-RAY DIFFRACTION 1.60Å
e2ji7A2[A:7-194]
nonrep
Image
Pymol
Jmol Links:
PDB,
SCOP,
CATH, PubMed,
DOI
OXALYL-COA DECARBOXYLASE ; ligands: ADP,B3P,OXT,PGE ; X-RAY DIFFRACTION 1.82Å
e1zpdA2[A:2-187]
nonrep
Image
Pymol
Jmol Links:
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SCOP,
CATH, PubMed,
DOI
PYRUVATE DECARBOXYLASE ; ligands: CIT,DPX ; X-RAY DIFFRACTION 1.86Å
e1ozhA2[A:7-187]
nonrep
Image
Pymol
Jmol Links:
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CATH, PubMed,
DOI
ACETOLACTATE SYNTHASE, CATABOLIC ; ligands: HE3 ; X-RAY DIFFRACTION 2.0Å
e2ihtA2[A:12-197]
nonrep
Image
Pymol
Jmol Links:
PDB,
SCOP,
CATH, PubMed,
DOI
CARBOXYETHYLARGININE SYNTHASE ; ligands: SO4,TPP ; X-RAY DIFFRACTION 2.0Å
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