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X - Possible homology level

H - Homology level

T - Topology level

F - Family level

* - Provisional representative


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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

X: Alpha-beta plaits
H: Adenylyl and guanylyl cyclase catalytic domain-like
T: Adenylyl and guanylyl cyclase catalytic domain-like
F: GGDEF

PF00990 CL0276

Representatives:

e3ezuA1[A:186-341] nonrep Image Pymol Jmol Links: PDB, SCOP, CATH

GGDEF domain protein ; X-RAY DIFFRACTION 1.95Å

e1w25A1[A:294-455] nonrep Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

STALKED-CELL DIFFERENTIATION CONTROLLING PROTEIN ; ligands: C2E ; X-RAY DIFFRACTION 2.700Å

e4zmmA1[A:178-341] Image Pymol Jmol Links: PDB, SCOP, CATH

diguanylate cyclase ; ligands: C2E ; X-RAY DIFFRACTION 2.5Å

e4zmmB1[B:181-341] Image Pymol Jmol Links: PDB, SCOP, CATH

diguanylate cyclase ; ligands: C2E ; X-RAY DIFFRACTION 2.5Å

e2v0nA1[A:294-454] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

RESPONSE REGULATOR PLED ; ligands: C2E,CL,GAV,MG ; X-RAY DIFFRACTION 2.70Å

e2v0nB1[B:294-454] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

RESPONSE REGULATOR PLED ; ligands: C2E,GAV,MG ; X-RAY DIFFRACTION 2.70Å

e1w25B1[B:294-455] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

STALKED-CELL DIFFERENTIATION CONTROLLING PROTEIN ; ligands: C2E ; X-RAY DIFFRACTION 2.700Å

e3hvwA1[A:171-333] Image Pymol Jmol Links: PDB, SCOP, CATH

Diguanylate-cyclase (DGC) ; X-RAY DIFFRACTION 1.7Å

e3mtkA1[A:186-353] Image Pymol Jmol Links: PDB, SCOP, CATH

Diguanylate cyclase/phosphodiesterase ; X-RAY DIFFRACTION 2.240Å

e2wb4A1[A:294-459] Image Pymol Jmol Links: PDB, SCOP, CATH

DIGUANYLATE CYCLASE ; ligands: C2E,SO4 ; X-RAY DIFFRACTION 2.8Å

e3qyyA1[A:134-290] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Response regulator ; ligands: C2E,MG,PEG ; X-RAY DIFFRACTION 1.90Å

e3iclA1[A:0-161] Image Pymol Jmol Links: PDB, SCOP, CATH

EAL/GGDEF domain protein ; ligands: SO4 ; X-RAY DIFFRACTION 2.000Å

e3ignA1[A:152-317] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Diguanylate cyclase ; ligands: C2E ; X-RAY DIFFRACTION 1.83Å

e3tvkA1[A:126-297] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Diguanylate cyclase DgcZ ; ligands: C2E,MG,TAR ; X-RAY DIFFRACTION 1.800Å

e3i5aA1[A:174-334] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Response regulator/GGDEF domain protein ; ligands: C2E ; X-RAY DIFFRACTION 2.796Å

e2wb4B1[B:294-454] Image Pymol Jmol Links: PDB, SCOP, CATH

DIGUANYLATE CYCLASE ; ligands: C2E,MG,SO4 ; X-RAY DIFFRACTION 2.8Å

e3mtkB1[B:186-353] Image Pymol Jmol Links: PDB, SCOP, CATH

Diguanylate cyclase/phosphodiesterase ; X-RAY DIFFRACTION 2.240Å

e3iclB1[B:7-161] Image Pymol Jmol Links: PDB, SCOP, CATH

EAL/GGDEF domain protein ; ligands: SO4 ; X-RAY DIFFRACTION 2.000Å

e3hvaA1[A:266-427] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

PROTEIN FIMX ; X-RAY DIFFRACTION 2.04Å

e3hvaB1[B:266-427] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

PROTEIN FIMX ; X-RAY DIFFRACTION 2.04Å

e3qyyB1[B:130-290] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Response regulator ; ligands: C2E,MG,PEG ; X-RAY DIFFRACTION 1.90Å

e3pjxA1[A:219-399] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Cyclic dimeric GMP binding protein ; ligands: EDO ; X-RAY DIFFRACTION 2.0Å

e4h54A1[A:127-296] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

DIGUANYLATE CYCLASE YDEH ; ligands: C2E,GAV,MG ; X-RAY DIFFRACTION 3.9Å

e4iobA1[A:254-414] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Diguanylate cyclase TpbB ; ligands: GOL,TBU ; X-RAY DIFFRACTION 2.78Å

e3pjwA3[A:241-407] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Cyclic dimeric GMP binding protein ; X-RAY DIFFRACTION 3.1Å

e4urgA1[A:90-239] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

DIGUANYLATE CYCLASE ; ligands: C2E ; X-RAY DIFFRACTION 1.90Å

e4urgB1[B:91-246] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

DIGUANYLATE CYCLASE ; X-RAY DIFFRACTION 1.90Å

e4urqU1[U:93-246] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

DIGUANYLATE CYCLASE ; X-RAY DIFFRACTION 2.50Å

e4urqV1[V:94-246] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

DIGUANYLATE CYCLASE ; X-RAY DIFFRACTION 2.50Å

e4urqW1[W:93-246] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

DIGUANYLATE CYCLASE ; X-RAY DIFFRACTION 2.50Å

e4urqX1[X:93-246] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

DIGUANYLATE CYCLASE ; X-RAY DIFFRACTION 2.50Å

e4urqY1[Y:93-246] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

DIGUANYLATE CYCLASE ; X-RAY DIFFRACTION 2.50Å

e4urqZ1[Z:94-246] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

DIGUANYLATE CYCLASE ; X-RAY DIFFRACTION 2.50Å

e4ursA1[A:87-248] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

DIGUANYLATE CYCLASE ; ligands: C2E,GOL,MES ; X-RAY DIFFRACTION 2.27Å

e4ursB1[B:87-248] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

DIGUANYLATE CYCLASE ; ligands: C2E,GOL,MES ; X-RAY DIFFRACTION 2.27Å

e4rnfA2[A:1-171] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Motility regulator ; X-RAY DIFFRACTION 2.850Å

e4rnhA2[A:977-1148] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Motility regulator ; X-RAY DIFFRACTION 2.45Å

e4ymeA1[A:372-527] Image Pymol Jmol Links: PDB, SCOP, CATH

sensory box/GGDEF family protein ; X-RAY DIFFRACTION 1.40Å

e3i5bA1[A:169-338] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

WspR response regulator ; ligands: TLA ; X-RAY DIFFRACTION 2.03Å

e3i5bB1[B:169-337] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

WspR response regulator ; ligands: TLA ; X-RAY DIFFRACTION 2.03Å

e3breA2[A:176-339] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Probable two-component response regulator ; ligands: C2E ; X-RAY DIFFRACTION 2.390Å

e3breB1[B:176-340] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Probable two-component response regulator ; ligands: C2E ; X-RAY DIFFRACTION 2.390Å

e4zveA1[A:298-458] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Diguanylate cyclase DosC ; ligands: CIT,EDO ; X-RAY DIFFRACTION 1.20Å

e4zvfA1[A:297-460] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Diguanylate cyclase DosC ; ligands: CA,EDO,GAV ; X-RAY DIFFRACTION 1.15Å

e4zvgA1[A:297-461] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Diguanylate cyclase DosC ; X-RAY DIFFRACTION 2.20Å

e4zvgB1[B:298-461] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Diguanylate cyclase DosC ; X-RAY DIFFRACTION 2.20Å

e4zvhA1[A:298-460] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Diguanylate cyclase DosC ; ligands: SO4 ; X-RAY DIFFRACTION 3.30Å

e4zvhB1[B:298-458] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Diguanylate cyclase DosC ; ligands: SO4 ; X-RAY DIFFRACTION 3.30Å

e4wxoA1[A:302-483] Image Pymol Jmol Links: PDB, SCOP, CATH

Uncharacterized protein ; X-RAY DIFFRACTION 2.80Å

e4wxoB1[B:302-483] Image Pymol Jmol Links: PDB, SCOP, CATH

Uncharacterized protein ; X-RAY DIFFRACTION 2.80Å

e4wxoC1[C:302-483] Image Pymol Jmol Links: PDB, SCOP, CATH

Uncharacterized protein ; X-RAY DIFFRACTION 2.80Å

e4wxwA1[A:323-487] Image Pymol Jmol Links: PDB, SCOP, CATH

Uncharacterized protein ; ligands: MG ; X-RAY DIFFRACTION 1.8Å

e5euhA1[A:339-502] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Putative GGDEF domain membrane protein ; ligands: C2E,SO4 ; X-RAY DIFFRACTION 2.989Å

e5euhB1[B:339-502] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Putative GGDEF domain membrane protein ; ligands: C2E,SO4 ; X-RAY DIFFRACTION 2.989Å

e5euhC1[C:340-502] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Putative GGDEF domain membrane protein ; ligands: C2E,SO4 ; X-RAY DIFFRACTION 2.989Å

e5euhD1[D:340-502] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Putative GGDEF domain membrane protein ; ligands: C2E,SO4 ; X-RAY DIFFRACTION 2.989Å

e4zmuA1[A:180-341] Image Pymol Jmol Links: PDB, SCOP, CATH

diguanylate cyclase ; X-RAY DIFFRACTION 2.5Å

e4zmuB1[B:180-341] Image Pymol Jmol Links: PDB, SCOP, CATH

diguanylate cyclase ; X-RAY DIFFRACTION 2.5Å

e4zmuC2[C:180-341] Image Pymol Jmol Links: PDB, SCOP, CATH

diguanylate cyclase ; X-RAY DIFFRACTION 2.5Å

e4zmuD2[D:180-341] Image Pymol Jmol Links: PDB, SCOP, CATH

diguanylate cyclase ; X-RAY DIFFRACTION 2.5Å

e5llwB2[B:524-683] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Diguanylate cyclase (GGDEF) domain-containing protein ; X-RAY DIFFRACTION 2.800Å

e5llwA2[A:524-683] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Diguanylate cyclase (GGDEF) domain-containing protein ; X-RAY DIFFRACTION 2.800Å

e5llxA2[A:524-682] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Diguanylate cyclase (GGDEF) domain-containing protein ; ligands: GTP,MG ; X-RAY DIFFRACTION 2.800Å

e5llxB2[B:524-682] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Diguanylate cyclase (GGDEF) domain-containing protein ; ligands: GTP,MG ; X-RAY DIFFRACTION 2.800Å

e4h54B1[B:127-297] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

DIGUANYLATE CYCLASE YDEH ; ligands: GAV,MG ; X-RAY DIFFRACTION 3.9Å

e5xgbA2[A:372-557] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Uncharacterized protein ; X-RAY DIFFRACTION 2.28Å

e5m3cA1[A:809-974] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Diguanylate cyclase ; ligands: CA,GTP ; X-RAY DIFFRACTION 2.800Å

e5xgdA3[A:372-557] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Uncharacterized protein PA0861 ; ligands: GTP,MG ; X-RAY DIFFRACTION 2.800Å

e5xgeA1[A:372-557] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Uncharacterized protein PA0861 ; X-RAY DIFFRACTION 3.310Å

e5m3cB1[B:809-974] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Diguanylate cyclase ; ligands: CA,GTP ; X-RAY DIFFRACTION 2.800Å

e6eibB1[B:2-161] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Sensory box/GGDEF family protein ; ligands: ACT,EDO,SO4 ; X-RAY DIFFRACTION 1.94Å

e6et7B3[B:524-682] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Diguanylate cyclase (GGDEF) domain-containing protein ; X-RAY DIFFRACTION 2.850Å

e6eibA1[A:1-159] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Sensory box/GGDEF family protein ; ligands: ACT,EDO,SO4 ; X-RAY DIFFRACTION 1.94Å

e6eibC1[C:3-159] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Sensory box/GGDEF family protein ; ligands: ACT,EDO,SO4 ; X-RAY DIFFRACTION 1.94Å

e6eibD1[D:4-159] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Sensory box/GGDEF family protein ; ligands: ACT,EDO,SO4 ; X-RAY DIFFRACTION 1.94Å

e6et7A4[A:524-682] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Diguanylate cyclase (GGDEF) domain-containing protein ; X-RAY DIFFRACTION 2.850Å

e6d9mA2[A:3-163] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Fusion protein of Endolysin,Response receiver sensor diguanylate cyclase, GAF domain-containing ; ligands: GMP,GOL,GTP,MG,POP ; X-RAY DIFFRACTION 1.350Å

e6hbzA1[A:134-309] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

GGDEF domain protein ; ligands: C2E,CL ; X-RAY DIFFRACTION 1.790Å

e6hbzB1[B:135-310] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

GGDEF domain protein ; ligands: C2E,CL,EDO ; X-RAY DIFFRACTION 1.790Å

e6pwjA2[A:242-401] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

GGDEF and EAL domain-containing protein ; X-RAY DIFFRACTION 2.700Å

e6pwjB2[B:221-396] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

GGDEF and EAL domain-containing protein ; X-RAY DIFFRACTION 2.700Å

e6pwkA1[A:222-397] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

GGDEF and EAL domain-containing protein ; ligands: C2E ; X-RAY DIFFRACTION 2.6Å

e6pwkB2[B:222-397] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

GGDEF and EAL domain-containing protein ; ligands: C2E ; X-RAY DIFFRACTION 2.6Å

e6khuA1[A:60-190] Image Pymol Jmol Links: PDB, SCOP, CATH

Diguanylate cyclase/phosphodiesterase-domain containing protein ; ligands: ZN ; X-RAY DIFFRACTION 2.0980Å

e6ttsA1[A:176-345] Image Pymol Jmol Links: PDB, SCOP, CATH

GGDEF diguanylate cyclase DgcB ; ligands: C2E,SO4 ; X-RAY DIFFRACTION 2.5Å

e6ttsB1[B:170-345] Image Pymol Jmol Links: PDB, SCOP, CATH

GGDEF diguanylate cyclase DgcB ; ligands: C2E,SO4 ; X-RAY DIFFRACTION 2.5Å

e6zxmA2[A:141-298] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Putative GGDEF/response regulator receiver domain protein ; ligands: C2E ; X-RAY DIFFRACTION 3.300Å

e6zxmC1[C:141-298] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Putative GGDEF/response regulator receiver domain protein ; ligands: C2E ; X-RAY DIFFRACTION 3.300Å

e6zxmD2[D:141-298] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Putative GGDEF/response regulator receiver domain protein ; ligands: C2E ; X-RAY DIFFRACTION 3.300Å

e6zxmE2[E:141-298] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Putative GGDEF/response regulator receiver domain protein ; ligands: C2E ; X-RAY DIFFRACTION 3.300Å

e6zxmF1[F:141-298] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Putative GGDEF/response regulator receiver domain protein ; ligands: C2E ; X-RAY DIFFRACTION 3.300Å

e6ttrA1[A:180-343] Image Pymol Jmol Links: PDB, SCOP, CATH

GGDEF diguanylate cyclase DgcB ; ligands: C2E,PO4 ; X-RAY DIFFRACTION 2.85Å

e7a7eA1[A:250-421] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Diguanylate cyclase TpbB ; ligands: MG ; X-RAY DIFFRACTION 2.800Å

e7a7eB1[B:245-420] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Diguanylate cyclase TpbB ; ligands: MG ; X-RAY DIFFRACTION 2.800Å

e7a7eC1[C:250-421] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Diguanylate cyclase TpbB ; ligands: MG ; X-RAY DIFFRACTION 2.800Å

e6zxbA1[A:129-298] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Putative GGDEF/response regulator receiver domain protein ; ligands: EDO,GH3,MG,SO4 ; X-RAY DIFFRACTION 2.19Å

e6zxbB1[B:129-298] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Putative GGDEF/response regulator receiver domain protein ; ligands: EDO,GH3,MG,SO4 ; X-RAY DIFFRACTION 2.19Å

e6zxcA1[A:129-298] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Putative GGDEF/response regulator receiver domain protein ; ligands: GH3,MG ; X-RAY DIFFRACTION 2.70Å

e6zxcB1[B:134-298] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Putative GGDEF/response regulator receiver domain protein ; ligands: GH3,MG ; X-RAY DIFFRACTION 2.70Å

e6zxcC1[C:134-298] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Putative GGDEF/response regulator receiver domain protein ; ligands: GH3,MG ; X-RAY DIFFRACTION 2.70Å

e6zxcD1[D:129-298] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Putative GGDEF/response regulator receiver domain protein ; ligands: GH3,MG ; X-RAY DIFFRACTION 2.70Å

e6zxmB1[B:129-298] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Putative GGDEF/response regulator receiver domain protein ; ligands: C2E ; X-RAY DIFFRACTION 3.300Å

e8c05A1[A:123-312] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

; ligands: DPO,MG ; X-RAY DIFFRACTION 2.5Å

e3i5cA1[A:142-337] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Fusion of General control protein GCN4 and WSPR response regulator protein ; ligands: C2E,MG ; X-RAY DIFFRACTION 1.94Å

e3i5cB1[B:142-339] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI

Fusion of General control protein GCN4 and WSPR response regulator protein ; ligands: C2E ; X-RAY DIFFRACTION 1.94Å

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: LuxS, MPP, ThrRS/AlaRS common domain

looks like an elaborated ferredoxin

X: ClpS-like

contains a HTH motif

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