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
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
binds one zinc with two CxxC motifs on two beta-hairpins
binds two zincs. one in the same way as rubredoxin, probably related to rubredoxin. the other in a similar way as glucocorticoid receptor
binds zinc with one beta-hairpin and one helix, the helix binds DNA
Representatives:
e1lu0A1[A:1-29] nonrep Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Trypsin inhibitor I ; ligands: GOL,SO4,ZN ; X-RAY DIFFRACTION 1.03Å
e2letA1[A:1-28] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed,
TRYPSIN INHIBITOR II ; SOLUTION NMR
e1ha9A1[A:6-34] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
TRYPSIN INHIBITOR II ; SOLUTION NMR
e2it8A1[A:1-29] Image Pymol Jmol Links: PDB, SCOP, CATH
TRYPSIN INHIBITOR 2 ; SOLUTION NMR
e1w7zE1[E:1-28] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
TRYPSIN INHIBITOR II ; ligands: NA ; X-RAY DIFFRACTION 1.67Å
e2etiA1[A:1-28] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
TRYPSIN INHIBITOR II ; SOLUTION NMR
e2staI1[I:501-529] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
PROTEIN (TRYPSIN INHIBITOR) ; X-RAY DIFFRACTION 1.8Å
e2it7A1[A:1-28] Image Pymol Jmol Links: PDB, SCOP, CATH
Trypsin inhibitor 2 ; SOLUTION NMR
e1ppeI1[I:1-29] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
TRYPSIN INHIBITOR CMTI-I ; X-RAY DIFFRACTION 2.0Å
e1ib9A1[A:6-34] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
TRYPSIN INHIBITOR II ; SOLUTION NMR
e1w7zC1[C:1-28] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
TRYPSIN INHIBITOR II ; ligands: NA ; X-RAY DIFFRACTION 1.67Å
e1w7zH1[H:1-28] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
TRYPSIN INHIBITOR II ; X-RAY DIFFRACTION 1.67Å
e1w7zA1[A:1-28] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
TRYPSIN INHIBITOR II ; ligands: NA ; X-RAY DIFFRACTION 1.67Å
e3ctiA1[A:1-29] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
TRYPSIN INHIBITOR ; SOLUTION NMR
e1h9iI1[I:1-28] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
TRYPSIN INHIBITOR II ; X-RAY DIFFRACTION 1.900Å
e1w7zG1[G:1-28] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
TRYPSIN INHIBITOR II ; ligands: FMT ; X-RAY DIFFRACTION 1.67Å
e1w7zB1[B:1-28] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
TRYPSIN INHIBITOR II ; ligands: FMT,NA ; X-RAY DIFFRACTION 1.67Å
e1w7zF1[F:1-28] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
TRYPSIN INHIBITOR II ; ligands: FMT,NA ; X-RAY DIFFRACTION 1.67Å
e2ctiA1[A:1-29] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
TRYPSIN INHIBITOR ; SOLUTION NMR
e1f2sI1[I:301-328] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
TRYPSIN INHIBITOR A ; X-RAY DIFFRACTION 1.79Å
e2btcI1[I:501-529] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
PROTEIN (TRYPSIN INHIBITOR) ; X-RAY DIFFRACTION 1.5Å
e1mctI1[I:1-28] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
TRYPSIN INHIBITOR A ; X-RAY DIFFRACTION 1.6Å
e2stbI1[I:501-529] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
PROTEIN (TRYPSIN INHIBITOR) ; X-RAY DIFFRACTION 1.8Å
e1ctiA1[A:1-29] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
TRYPSIN INHIBITOR ; SOLUTION NMR
e1lu0B1[B:1-29] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Trypsin inhibitor I ; ligands: GOL,MRD,SO4,ZN ; X-RAY DIFFRACTION 1.03Å
e1w7zD1[D:1-28] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
TRYPSIN INHIBITOR II ; ligands: FMT,NA ; X-RAY DIFFRACTION 1.67Å
e2v1vA1[A:1-29] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
TRYPSIN INHIBITOR 1 ; SOLUTION NMR
e1h9hI1[I:1-28] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
TRYPSIN INHIBITOR II ; X-RAY DIFFRACTION 1.500Å
e2c4bA2[A:117-143] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
BARNASE MCOEETI FUSION ; ligands: 2PE,EDO,SO4,UNX ; X-RAY DIFFRACTION 1.300Å
e2c4bB2[B:117-143] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
BARNASE MCOEETI FUSION ; ligands: 2PE,EDO,SO4,UNX ; X-RAY DIFFRACTION 1.300Å
e1mcvI1[I:1-28] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
HEI-TOE I ; X-RAY DIFFRACTION 1.8Å
e2ljsA1[A:1-30] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Trypsin inhibitor 3 ; SOLUTION NMR
e2po8A1[A:1-34] Image Pymol Jmol Links: PDB, SCOP, CATH
MCoTI-II ; SOLUTION NMR
e2m86A1[A:1-51] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
MCO-PMI ; SOLUTION NMR
e4guxD1[D:1-34] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Trypsin inhibitor 2 ; X-RAY DIFFRACTION 1.80Å
e4guxE1[E:1-34] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Trypsin inhibitor 2 ; X-RAY DIFFRACTION 1.80Å
e4guxF1[F:1-34] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Trypsin inhibitor 2 ; X-RAY DIFFRACTION 1.80Å
e2m7tA1[A:1-33] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
CYSTINE KNOT PROTEIN 2.5D ; SOLUTION NMR
e2mt8A1[A:1-39] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
MTAbl13 of grafted MCoTI-II ; SOLUTION NMR
e2n8bA1[A:1-36] Image Pymol Jmol Links: PDB, SCOP, CATH
Cysteine knot ; SOLUTION NMR
e2n8cA1[A:1-37] Image Pymol Jmol Links: PDB, SCOP, CATH
Cysteine knot ; SOLUTION NMR
e5wovA1[A:1-34] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Two inhibitor peptide topologies 2 ; SOLUTION NMR
e5wowA1[A:1-39] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Two inhibitor peptide topologies 2 ; SOLUTION NMR
e6cdxA1[A:0-36] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
cystine knot (fluoropropylated) ; X-RAY DIFFRACTION 1Å
e6cdxB1[B:1-36] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
cystine knot (fluoropropylated) ; X-RAY DIFFRACTION 1Å
e6mm4A1[A:1-33] Image Pymol Jmol Links: PDB, SCOP, CATH
Engineered Cystine Knot Protein 2.5F ; SOLUTION NMR
e6mslC1[C:2-33] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Cystine Knot Protein 2.5D ; ligands: MN ; X-RAY DIFFRACTION 3.1Å
e6msuC1[C:2-33] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Engineered EETI-II 2.5F ; ligands: CL,MN ; X-RAY DIFFRACTION 3.1Å
e7fbpB1[B:1-34] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
cMCoFx1 ; X-RAY DIFFRACTION 1.99Å
e7namB1[B:1-32] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Trypsin inhibitor 2 ; X-RAY DIFFRACTION 1.600Å
e7mlaB1[B:1-34] Image Pymol Jmol Links: PDB, SCOP, CATH
MCo-52-2 ; SOLUTION NMR
e8dvmB1[B:1-30] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
E3.6 Disulfide constrained peptide ; ligands: EDO ; X-RAY DIFFRACTION 2.0Å
e8dvnB1[B:1-32] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
E3.10 Disulfide constrained peptide ; X-RAY DIFFRACTION 2.53Å
Pseudo group of domains that do not map to PFam family profiles. Domains inside should not be considered as in one family.
linked to omega toxin-like with lower scores
extended segmentsextended, non-globular segments, frequently bind to other proteins to form complexes