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X - Possible homology level

H - Homology level

T - Topology level

F - Family level

* - Provisional representative

Keyword search

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

X: jelly-roll
H: Galactose-binding domain-like
T: Galactose-binding domain-like
F: Ephrin_lbd

PF01404 CL0202

Representatives:

e2bbaA1[A:17-196] nonrep Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

EPHRIN TYPE-B RECEPTOR 4 ; ligands: SO4 ; X-RAY DIFFRACTION 1.65Å

e1kgyB1[B:228-404] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

EPHRIN TYPE-B RECEPTOR 2 ; X-RAY DIFFRACTION 2.7Å

e1nukA1[A:28-203] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

PROTEIN (TYROSINE-PROTEIN KINASE RECEPTOR EPH) ; X-RAY DIFFRACTION 2.9Å

e1kgyC1[C:428-604] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

EPHRIN TYPE-B RECEPTOR 2 ; X-RAY DIFFRACTION 2.7Å

e1shwB1[B:228-404] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-B receptor 2 ; X-RAY DIFFRACTION 2.0Å

e1kgyA1[A:28-204] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

EPHRIN TYPE-B RECEPTOR 2 ; X-RAY DIFFRACTION 2.7Å

e2hleA1[A:17-196] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

EPHRIN TYPE-B RECEPTOR 4 ; X-RAY DIFFRACTION 2.05Å

e1kgyD1[D:628-804] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

EPHRIN TYPE-B RECEPTOR 2 ; X-RAY DIFFRACTION 2.7Å

e2wo1A1[A:27-209] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

EPHRIN TYPE-A RECEPTOR ; ligands: POL ; X-RAY DIFFRACTION 1.85Å

e3nruA1[A:32-204] Image Pymol Jmol Links: PDB, SCOP, CATH

EPHRIN RECEPTOR ; ligands: SO4 ; X-RAY DIFFRACTION 2.3Å

e3p1iA1[A:38-211] Image Pymol Jmol Links: PDB, SCOP, CATH

EPHRIN TYPE-B RECEPTOR 3 ; ligands: SO4 ; X-RAY DIFFRACTION 2.1Å

e3skjE1[E:1-176] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 2 ; X-RAY DIFFRACTION 2.5Å

e2qbxA1[A:28-203] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

EPHRIN TYPE-B RECEPTOR 2 ; ligands: SO4 ; X-RAY DIFFRACTION 2.3Å

e3ckhA1[A:1-174] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 4 ; X-RAY DIFFRACTION 2.300Å

e2qbxB1[B:28-203] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

EPHRIN TYPE-B RECEPTOR 2 ; ligands: SO4 ; X-RAY DIFFRACTION 2.3Å

e3c8xA1[A:27-200] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 2 ; X-RAY DIFFRACTION 1.950Å

e3czuA1[A:27-201] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

EPHRIN TYPE-A RECEPTOR 2 ; X-RAY DIFFRACTION 2.65Å

e3ckhB1[B:1-174] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 4 ; X-RAY DIFFRACTION 2.300Å

e3etpA1[A:21-207] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-B receptor 2 ; X-RAY DIFFRACTION 2Å

e3heiA1[A:1-174] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 2 ; X-RAY DIFFRACTION 2.000Å

e3heiC1[C:1-174] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 2 ; X-RAY DIFFRACTION 2.000Å

e3heiE1[E:1-174] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 2 ; X-RAY DIFFRACTION 2.000Å

e3heiG1[G:1-174] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 2 ; X-RAY DIFFRACTION 2.000Å

e3heiI1[I:1-174] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 2 ; X-RAY DIFFRACTION 2.000Å

e3heiK1[K:1-174] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 2 ; X-RAY DIFFRACTION 2.000Å

e3heiM1[M:1-174] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 2 ; X-RAY DIFFRACTION 2.000Å

e3heiO1[O:1-174] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 2 ; X-RAY DIFFRACTION 2.000Å

e3hpnA1[A:1-174] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 2 ; X-RAY DIFFRACTION 2.5Å

e3hpnB1[B:1-174] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 2 ; X-RAY DIFFRACTION 2.5Å

e3hpnC1[C:1-174] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 2 ; X-RAY DIFFRACTION 2.5Å

e3hpnD1[D:1-174] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 2 ; X-RAY DIFFRACTION 2.5Å

e3hpnE1[E:1-174] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 2 ; X-RAY DIFFRACTION 2.5Å

e3hpnF1[F:1-174] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 2 ; X-RAY DIFFRACTION 2.5Å

e3gxuA1[A:1-175] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

EPHRIN TYPE-A RECEPTOR 4 ; X-RAY DIFFRACTION 2.5Å

e2wo1B1[B:29-204] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

EPHRIN TYPE-A RECEPTOR ; ligands: POL ; X-RAY DIFFRACTION 1.85Å

e2wo2A1[A:28-205] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

EPHRIN TYPE-A RECEPTOR ; X-RAY DIFFRACTION 2.45Å

e2wo3A1[A:28-203] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

EPHRIN TYPE-A RECEPTOR ; X-RAY DIFFRACTION 2.35Å

e3nruB1[B:32-204] Image Pymol Jmol Links: PDB, SCOP, CATH

EPHRIN RECEPTOR ; ligands: CL,SO4 ; X-RAY DIFFRACTION 2.3Å

e3nruC1[C:31-204] Image Pymol Jmol Links: PDB, SCOP, CATH

EPHRIN RECEPTOR ; ligands: CL,SO4 ; X-RAY DIFFRACTION 2.3Å

e3nruD1[D:31-204] Image Pymol Jmol Links: PDB, SCOP, CATH

EPHRIN RECEPTOR ; ligands: SO4 ; X-RAY DIFFRACTION 2.3Å

e3nruE1[E:31-204] Image Pymol Jmol Links: PDB, SCOP, CATH

EPHRIN RECEPTOR ; ligands: SO4 ; X-RAY DIFFRACTION 2.3Å

e3nruF1[F:31-204] Image Pymol Jmol Links: PDB, SCOP, CATH

EPHRIN RECEPTOR ; X-RAY DIFFRACTION 2.3Å

e3nruG1[G:30-204] Image Pymol Jmol Links: PDB, SCOP, CATH

EPHRIN RECEPTOR ; ligands: SO4 ; X-RAY DIFFRACTION 2.3Å

e3nruH1[H:31-204] Image Pymol Jmol Links: PDB, SCOP, CATH

EPHRIN RECEPTOR ; X-RAY DIFFRACTION 2.3Å

e3nruI1[I:31-204] Image Pymol Jmol Links: PDB, SCOP, CATH

EPHRIN RECEPTOR ; X-RAY DIFFRACTION 2.3Å

e3nruJ1[J:31-204] Image Pymol Jmol Links: PDB, SCOP, CATH

EPHRIN RECEPTOR ; ligands: SO4 ; X-RAY DIFFRACTION 2.3Å

e3nruK1[K:31-204] Image Pymol Jmol Links: PDB, SCOP, CATH

EPHRIN RECEPTOR ; ligands: SO4 ; X-RAY DIFFRACTION 2.3Å

e3nruL1[L:32-202] Image Pymol Jmol Links: PDB, SCOP, CATH

EPHRIN RECEPTOR ; ligands: SO4 ; X-RAY DIFFRACTION 2.3Å

e3p1iB1[B:39-210] Image Pymol Jmol Links: PDB, SCOP, CATH

EPHRIN TYPE-B RECEPTOR 3 ; ligands: CL,SO4 ; X-RAY DIFFRACTION 2.1Å

e3p1iC1[C:39-210] Image Pymol Jmol Links: PDB, SCOP, CATH

EPHRIN TYPE-B RECEPTOR 3 ; X-RAY DIFFRACTION 2.1Å

e4et7A1[A:59-232] Image Pymol Jmol Links: PDB, SCOP, CATH

EPHRIN TYPE-A RECEPTOR 5 ; X-RAY DIFFRACTION 2.6Å

e4bk4B1[B:27-203] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

EPHRIN TYPE-A RECEPTOR 4 ; X-RAY DIFFRACTION 3.65Å

e2lw8A1[A:1-183] Image Pymol Jmol Links: PDB, SCOP, CATH

EPHRIN TYPE-A RECEPTOR 4 ; SOLUTION NMR

e2x10A4[A:26-199] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

EPHRIN TYPE-A RECEPTOR 2 ; ligands: CL ; X-RAY DIFFRACTION 3.00Å

e3skjF2[F:28-96,F:121-142,F:163-170] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 2 ; X-RAY DIFFRACTION 2.5Å

e3fl7A3[A:25-199] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

EPHRIN RECEPTOR ; ligands: CL,NA ; X-RAY DIFFRACTION 2.5Å

e2x11A19[A:27-199] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

EPHRIN TYPE-A RECEPTOR 2 ; X-RAY DIFFRACTION 4.80Å

e4l0pA1[A:27-201] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 3 ; ligands: SO4 ; X-RAY DIFFRACTION 2.26Å

e4w4zA1[A:28-204] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 4 ; ligands: GOL,HEZ ; X-RAY DIFFRACTION 2.410Å

e4w4zB1[B:28-204] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 4 ; ligands: GOL,HEZ ; X-RAY DIFFRACTION 2.410Å

e4w4zC1[C:28-204] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 4 ; ligands: GOL,HEZ ; X-RAY DIFFRACTION 2.410Å

e4w4zD1[D:28-204] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 4 ; ligands: GOL,HEZ ; X-RAY DIFFRACTION 2.410Å

e4w50A1[A:28-204] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 4 ; ligands: BU2,GOL ; X-RAY DIFFRACTION 2.420Å

e4w50B1[B:28-204] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 4 ; ligands: BU2,GOL ; X-RAY DIFFRACTION 2.420Å

e4w50C1[C:28-204] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 4 ; ligands: BU2,GOL ; X-RAY DIFFRACTION 2.420Å

e4w50D1[D:28-204] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 4 ; ligands: BU2,GOL ; X-RAY DIFFRACTION 2.420Å

e4bk5A1[A:27-203] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

EPHRIN TYPE-A RECEPTOR 4 ; X-RAY DIFFRACTION 4.00Å

e4bkaA1[A:27-203] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

EPHRIN TYPE-A RECEPTOR 4 ; X-RAY DIFFRACTION 4.95Å

e4bkfB1[B:28-209] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

EPHRIN TYPE-A RECEPTOR 4 ; X-RAY DIFFRACTION 4.65Å

e4m4pA1[A:27-209] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

EPHRIN TYPE-A RECEPTOR 4 ; X-RAY DIFFRACTION 2.08Å

e5jr2A1[A:28-204] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 4 ; ligands: GOL,HEZ ; X-RAY DIFFRACTION 1.75Å

e5jr2B1[B:28-204] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 4 ; ligands: GOL,HEZ ; X-RAY DIFFRACTION 1.75Å

e5jr2C1[C:28-204] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 4 ; ligands: GOL,HEZ ; X-RAY DIFFRACTION 1.75Å

e5jr2D1[D:28-204] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 4 ; ligands: GOL ; X-RAY DIFFRACTION 1.75Å

e3mbwA1[A:25-200] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

EPHRIN TYPE-A RECEPTOR 2 ; ligands: UNX ; X-RAY DIFFRACTION 2.81Å

e3mx0A3[A:27-201] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 2 ; X-RAY DIFFRACTION 3.500Å

e3mx0C3[C:27-201] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 2 ; X-RAY DIFFRACTION 3.500Å

e4m4rC4[C:27-260] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

EPHRIN TYPE-A RECEPTOR 4 ; X-RAY DIFFRACTION 3.13Å

e4m4rE4[E:27-260] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

EPHRIN TYPE-A RECEPTOR 4 ; X-RAY DIFFRACTION 3.13Å

e4m4rG4[G:27-260] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

EPHRIN TYPE-A RECEPTOR 4 ; X-RAY DIFFRACTION 3.13Å

e6b9lA1[A:27-200] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 2 ; X-RAY DIFFRACTION 3.200Å

e6b9lB1[B:27-200] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 2 ; X-RAY DIFFRACTION 3.200Å

e6b9lC1[C:27-200] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 2 ; X-RAY DIFFRACTION 3.200Å

e6b9lD1[D:27-200] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 2 ; X-RAY DIFFRACTION 3.200Å

e6nk0A1[A:27-207] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 2 ; ligands: ACA,EDO,GOL ; X-RAY DIFFRACTION 1.530Å

e6njzA1[A:27-205] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 2 ; ligands: BTN,GOL ; X-RAY DIFFRACTION 1.90Å

e6njzB1[B:26-205] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 2 ; ligands: BTN,GOL ; X-RAY DIFFRACTION 1.90Å

e6nk0B1[B:27-207] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 2 ; ligands: EDO,GOL,NH2,PEG ; X-RAY DIFFRACTION 1.530Å

e6nk1A1[A:27-207] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 2 ; X-RAY DIFFRACTION 1.550Å

e6nk1B1[B:27-200] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 2 ; ligands: ACT,GOL ; X-RAY DIFFRACTION 1.550Å

e6nk2A1[A:25-201] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 2 ; ligands: PEG ; X-RAY DIFFRACTION 2.20Å

e6nk2B1[B:23-201] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 2 ; X-RAY DIFFRACTION 2.20Å

e6nkpA1[A:26-200] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 2 ; ligands: BTN ; X-RAY DIFFRACTION 2.03Å

e6nkpB1[B:26-204] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 2 ; ligands: BTN ; X-RAY DIFFRACTION 2.03Å

e6rw2A1[A:27-201] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 2 ; ligands: 29N,GOL ; X-RAY DIFFRACTION 2.26Å

e7czeI1[I:27-200] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 2 ; X-RAY DIFFRACTION 3.00Å

e7czeJ1[J:27-200] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 2 ; X-RAY DIFFRACTION 3.00Å

e7czeK1[K:27-200] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 2 ; X-RAY DIFFRACTION 3.00Å

e7czeL1[L:27-200] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 2 ; X-RAY DIFFRACTION 3.00Å

e7czfA1[A:28-210] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 2 ; X-RAY DIFFRACTION 3.20Å

e7czfD1[D:28-198] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 2 ; X-RAY DIFFRACTION 3.20Å

e7b7nE1[E:27-200] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-A receptor 2 ; ligands: CL,NA ; X-RAY DIFFRACTION 2.69Å

e7k7jA3[A:1-131,A:154-201] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-B receptor 6 ; X-RAY DIFFRACTION 3Å

e7s7kA1[A:19-196] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Ephrin type-B receptor 2 ; X-RAY DIFFRACTION 3.145Å

e4bk4A1[A:27-201] nonrep Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

EPHRIN TYPE-A RECEPTOR 4 ; X-RAY DIFFRACTION 3.65Å

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.

X: Glycosyl hydrolase domain-like

some similarity with Ig fold

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

extended segmentsextended, non-globular segments, frequently bind to other proteins to form complexes