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
Pseudo group of domains that do not map to PFam family profiles. Domains inside should not be considered as in one family.
Representatives:
e6dgaA1[A:1-95] nonrep Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
RpfR ; X-RAY DIFFRACTION 1.190Å
e4kqdB1[B:13-128] nonrep Image Pymol Jmol Links: PDB, SCOP, CATH
Protein TraJ ; ligands: DTD ; X-RAY DIFFRACTION 1.55Å
e6ceqA1[A:170-280] * nonrep Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis protein ; ligands: HEM ; X-RAY DIFFRACTION 1.590Å
e3by9A2[A:185-212,A:234-285] * nonrep Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Sensor protein ; ligands: CA ; X-RAY DIFFRACTION 1.600Å
e3t4jB2[B:336-393] * nonrep Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
HISTIDINE KINASE 4 ; X-RAY DIFFRACTION 1.65Å
e6mniA1[A:200-286] * nonrep Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis protein ; X-RAY DIFFRACTION 1.6960Å
e5gpoB1[B:36-161] * nonrep Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Sensor protein CzcS ; ligands: SO4,ZN ; X-RAY DIFFRACTION 1.70Å
e6mabA1[A:42-75,A:193-312] nonrep Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Sigma regulatory family protein-PP2C phosphatase ; ligands: IPA ; X-RAY DIFFRACTION 1.700Å
e6mabA2[A:76-192] nonrep Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Sigma regulatory family protein-PP2C phosphatase ; X-RAY DIFFRACTION 1.700Å
e4hh3B4[B:5-140] * nonrep Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Transcriptional regulator, PpsR ; X-RAY DIFFRACTION 1.75Å
e3li8A2[A:210-303] * nonrep Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Hypothetical sensory transduction histidine kinase ; X-RAY DIFFRACTION 1.750Å
e3citA1[A:16-172] * nonrep Image Pymol Jmol Links: PDB, SCOP, CATH
Sensor histidine kinase ; ligands: EDO,GOL,SO4 ; X-RAY DIFFRACTION 1.900Å
e5ereA4[A:497-532,A:557-593] * nonrep Image Pymol Jmol Links: PDB, SCOP, CATH
Extracellular ligand-binding receptor ; ligands: ACY ; X-RAY DIFFRACTION 2.00Å
e3cloB2[B:1-189] nonrep Image Pymol Jmol Links: PDB, SCOP, CATH
Transcriptional regulator ; ligands: CL ; X-RAY DIFFRACTION 2.04Å
e5xhxA1[A:7-178] * nonrep Image Pymol Jmol Links: PDB, SCOP, CATH
Helix-turn-helix transcriptional regulator ; X-RAY DIFFRACTION 2.1Å
e2p7jA2[A:9-180] nonrep Image Pymol Jmol Links: PDB, SCOP, CATH
PUTATIVE SENSORY BOX/GGDEF FAMILY PROTEIN ; ligands: SO4 ; X-RAY DIFFRACTION 2.25Å
e6e09B1[B:56-125,B:145-195] * nonrep Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis protein TlpA ; X-RAY DIFFRACTION 2.3Å
e6e09B2[B:29-55,B:196-288] * nonrep Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis protein TlpA ; X-RAY DIFFRACTION 2.3Å
e3licA2[A:212-303] * nonrep Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Sensor protein ; X-RAY DIFFRACTION 2.300Å
e3c8cA2[A:211-300] Image Pymol Jmol Links: PDB, SCOP, CATH
Methyl-accepting chemotaxis protein ; ligands: ALA,MG ; X-RAY DIFFRACTION 1.460Å
e3c8cB2[B:211-300] Image Pymol Jmol Links: PDB, SCOP, CATH
Methyl-accepting chemotaxis protein ; ligands: ALA,MG ; X-RAY DIFFRACTION 1.460Å
e4xmqB2[B:207-290] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Putative methyl-accepting chemotaxis signal transduction protein ; ligands: SO4 ; X-RAY DIFFRACTION 1.5Å
e4xmrB2[B:209-290] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Putative methyl-accepting chemotaxis signal transduction protein ; X-RAY DIFFRACTION 1.300Å
e4xmrA2[A:207-285] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Putative methyl-accepting chemotaxis signal transduction protein ; X-RAY DIFFRACTION 1.300Å
e4xmqA2[A:209-285] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Putative methyl-accepting chemotaxis signal transduction protein ; X-RAY DIFFRACTION 1.5Å
e5aveA1[A:211-308] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis (MCP) signaling domain protein ; X-RAY DIFFRACTION 1.8Å
e4wy9A2[A:232-326] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Putative MCP-type signal transduction protein ; ligands: ACT ; X-RAY DIFFRACTION 1.400Å
e5avfA2[A:211-296] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis (MCP) signaling domain protein ; X-RAY DIFFRACTION 1.95Å
e5avfB1[B:211-296] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis (MCP) signaling domain protein ; X-RAY DIFFRACTION 1.95Å
e5t65A2[A:183-269] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis protein PctA ; ligands: ACT,ILE,SO4 ; X-RAY DIFFRACTION 2.20Å
e5t65B2[B:183-273] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis protein PctA ; ligands: ACT,ILE ; X-RAY DIFFRACTION 2.20Å
e5ltxA2[A:183-272] Image Pymol Jmol Links: PDB, SCOP, CATHDOI
Chemotaxis protein ; ligands: ACT,FMT,GOL,MET ; X-RAY DIFFRACTION 2.020Å
e5t7mA1[A:183-270] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Chemotaxis protein ; ligands: ACT,TRP ; X-RAY DIFFRACTION 2.25Å
e5lt9A2[A:183-272] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis protein PctB ; ligands: ARG,NA ; X-RAY DIFFRACTION 3.000Å
e5lt9B2[B:183-292] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis protein PctB ; X-RAY DIFFRACTION 3.000Å
e5ltoA1[A:183-272] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis protein PctB ; ligands: GLN,SO4 ; X-RAY DIFFRACTION 3.459Å
e5ltoB1[B:183-273,B:281-293] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis protein PctB ; X-RAY DIFFRACTION 3.459Å
e5ltvA1[A:186-265] Image Pymol Jmol Links: PDB, SCOP, CATHDOI
Chemotactic transducer PctC ; X-RAY DIFFRACTION 2.310Å
e5ltvC2[C:186-265] Image Pymol Jmol Links: PDB, SCOP, CATHDOI
Chemotactic transducer PctC ; X-RAY DIFFRACTION 2.310Å
e5ltvG1[G:186-264] Image Pymol Jmol Links: PDB, SCOP, CATHDOI
Chemotactic transducer PctC ; ligands: GOL ; X-RAY DIFFRACTION 2.310Å
e5ltxB2[B:183-271] Image Pymol Jmol Links: PDB, SCOP, CATHDOI
Chemotaxis protein ; ligands: FMT,MET ; X-RAY DIFFRACTION 2.020Å
e5t7mB2[B:183-271] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Chemotaxis protein ; ligands: ACT,NA,TRP ; X-RAY DIFFRACTION 2.25Å
e5ltvB2[B:186-266] Image Pymol Jmol Links: PDB, SCOP, CATHDOI
Chemotactic transducer PctC ; X-RAY DIFFRACTION 2.310Å
e5ltvD1[D:186-266] Image Pymol Jmol Links: PDB, SCOP, CATHDOI
Chemotactic transducer PctC ; X-RAY DIFFRACTION 2.310Å
e5ltvE2[E:186-266] Image Pymol Jmol Links: PDB, SCOP, CATHDOI
Chemotactic transducer PctC ; ligands: ACT ; X-RAY DIFFRACTION 2.310Å
e5ltvF1[F:186-266] Image Pymol Jmol Links: PDB, SCOP, CATHDOI
Chemotactic transducer PctC ; X-RAY DIFFRACTION 2.310Å
e5wbfA2[A:194-293] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis transducer (TlpC) ; ligands: LAC ; X-RAY DIFFRACTION 2.190Å
e5wbfB2[B:194-294] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis transducer (TlpC) ; ligands: LAC ; X-RAY DIFFRACTION 2.190Å
e5wbfC2[C:194-294] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis transducer (TlpC) ; ligands: GOL,LAC ; X-RAY DIFFRACTION 2.190Å
e6iosA2[A:182-266] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis protein ; X-RAY DIFFRACTION 2.35Å
e6iouA1[A:182-269] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis protein ; ligands: SER,TRS ; X-RAY DIFFRACTION 2.10Å
e6iouB1[B:182-269] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis protein ; ligands: SER,TRS ; X-RAY DIFFRACTION 2.10Å
e6ioqA2[A:182-263] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis protein ; X-RAY DIFFRACTION 2.14Å
e6iorA2[A:182-268] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis protein ; X-RAY DIFFRACTION 2.50Å
e6iopA2[A:182-266] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis protein ; X-RAY DIFFRACTION 2.30Å
e6iopB2[B:182-265] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis protein ; X-RAY DIFFRACTION 2.30Å
e6iorB1[B:182-268] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis protein ; X-RAY DIFFRACTION 2.50Å
e6iorC1[C:182-267] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis protein ; X-RAY DIFFRACTION 2.50Å
e6iorD2[D:182-267] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis protein ; X-RAY DIFFRACTION 2.50Å
e6iotA1[A:182-265] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis protein ; X-RAY DIFFRACTION 2.70Å
e6iotB2[B:182-265] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis protein ; X-RAY DIFFRACTION 2.70Å
e6iotC2[C:182-268] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis protein ; X-RAY DIFFRACTION 2.70Å
e6iotD1[D:182-265] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis protein ; X-RAY DIFFRACTION 2.70Å
e6iovA2[A:211-288] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis (MCP) signaling domain protein ; X-RAY DIFFRACTION 2.35Å
e6iovB1[B:211-291] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis (MCP) signaling domain protein ; X-RAY DIFFRACTION 2.35Å
e6py3B1[B:183-271] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Putative methyl-accepting chemotaxis protein ; X-RAY DIFFRACTION 1.900Å
e6pxyA1[A:183-269] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Putative methyl-accepting chemotaxis protein ; X-RAY DIFFRACTION 2.000Å
e6py5A1[A:183-266] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Putative methyl-accepting chemotaxis protein ; X-RAY DIFFRACTION 1.900Å
e6q0fA1[A:183-266] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Putative methyl-accepting chemotaxis protein ; X-RAY DIFFRACTION 2.200Å
e6q0gA1[A:183-269] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Putative methyl-accepting chemotaxis protein ; X-RAY DIFFRACTION 2.000Å
e6py3A2[A:183-270] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Putative methyl-accepting chemotaxis protein ; X-RAY DIFFRACTION 1.900Å
e6py4A1[A:183-269] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Putative methyl-accepting chemotaxis protein ; X-RAY DIFFRACTION 2.000Å
e6pyiA1[A:183-269] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Putative methyl-accepting chemotaxis protein ; X-RAY DIFFRACTION 1.95Å
e6w3oB1[B:207-290] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis protein ; X-RAY DIFFRACTION 1.42Å
e6w3pB2[B:207-290] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis protein ; ligands: CL ; X-RAY DIFFRACTION 1.38Å
e6w3rB2[B:207-290] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis protein ; X-RAY DIFFRACTION 1.38Å
e6w3sB1[B:207-290] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis protein ; ligands: GOL,LEU ; X-RAY DIFFRACTION 1.40Å
e6w3tB2[B:207-290] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis protein ; ligands: GOL ; X-RAY DIFFRACTION 2.10Å
e6w3vB2[B:207-290] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis protein ; ligands: NA,PHE ; X-RAY DIFFRACTION 1.38Å
e6w3xB1[B:207-290] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis protein ; ligands: GOL,VAL ; X-RAY DIFFRACTION 1.40Å
e6w3yB2[B:207-290] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis protein ; ligands: ALA,GOL ; X-RAY DIFFRACTION 1.32Å
e6w3oA1[A:207-285] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis protein ; ligands: NA ; X-RAY DIFFRACTION 1.42Å
e6w3sA1[A:207-285] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis protein ; ligands: GOL,LEU ; X-RAY DIFFRACTION 1.40Å
e6w3tA2[A:207-285] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis protein ; ligands: GOL ; X-RAY DIFFRACTION 2.10Å
e6w3xA2[A:207-285] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis protein ; ligands: GOL,VAL ; X-RAY DIFFRACTION 1.40Å
e6w3yA2[A:207-285] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis protein ; X-RAY DIFFRACTION 1.32Å
e6w3pA2[A:209-285] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis protein ; ligands: CL,GOL,NA ; X-RAY DIFFRACTION 1.38Å
e6w3rA2[A:209-285] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis protein ; ligands: NA ; X-RAY DIFFRACTION 1.38Å
e6w3vA2[A:209-285] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis protein ; X-RAY DIFFRACTION 1.38Å
e7k5nA2[A:207-280] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Sensor domain-containing diguanylate cyclase ; ligands: GOL,PRO ; X-RAY DIFFRACTION 1.80Å
e7psgC1[C:198-287] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis protein ; X-RAY DIFFRACTION 1.910Å
e7psgB2[B:198-284] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis protein ; X-RAY DIFFRACTION 1.910Å
e7psgD2[D:198-284] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis protein ; X-RAY DIFFRACTION 1.910Å
e7psgA2[A:198-285] Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Methyl-accepting chemotaxis protein ; X-RAY DIFFRACTION 1.910Å
e6hmjB2[B:10-120] * nonrep Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Putative PAS/PAC sensor protein ; X-RAY DIFFRACTION 2.51Å
e6k62B1[B:5-27,B:202-264] nonrep Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
Histidine kinase ; X-RAY DIFFRACTION 2.55Å
e3dteA2[A:127-263] nonrep Image Pymol Jmol Links: PDB, SCOP, CATH, PubMed, DOI
IRRE PROTEIN ; X-RAY DIFFRACTION 2.6Å
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