1A31: Protein

Human reconstituted DNA topoisomerase I in covalent complex with a 22 base pair DNA duplex. Determined by X-ray diffraction at 2.1 Å resolution. Released 28 Aug 1998.

Method
X-ray diffraction
Resolution
2.1 Å
Organism
Homo sapiens
Chains
3
Atoms
4,991
Mol. weight
84.73 kDa
Released
28 Aug 1998

Explore 1A31 in 3D Show helices and sheets RCSB PDB PDBe

Secondary structure: helices and β-sheets

1A31 contains 29 α-helices and 21 β-strands across 1 chain. Residue ranges use author residue numbering, as in the PDB file, from PDBe. To see them in 3D, choose the Cartoon representation with Secondary structure coloring: helices, sheets and coils get different colors.

Chain A: 29 helices, 21 β-strands

ElementResiduesLengthSheet
β-strand220-22231
β-strand22612
α-helix227-2315
α-helix233-2353
β-strand241-24223
β-strand245-24623
α-helix248-2503
α-helix251-26111
α-helix267-2704
α-helix272-28514
α-helix288-2936
α-helix297-2993
β-strand300-30123
α-helix303-31715
α-helix321-33818
β-strand340-34341
β-strand346-34941
β-strand35014
β-strand35412
α-helix355-3573
β-strand359-36025
α-helix3721
β-strand373-37425
α-helix375-3784
α-helix379-3813
β-strand383-38536
α-helix391-3955
β-strand403-40536
β-strand414-41746
α-helix4231
β-strand424-42746
β-strand42914
α-helix434-46431
α-helix470-48516
α-helix504-5063
β-strand50817
α-helix509-5113
β-strand514-51858
β-strand521-530108
α-helix532-5343
β-strand536-54278
α-helix545-5539
β-strand56317
α-helix570-58011
α-helix586-60520
α-helix612-62514
α-helix726-73510
α-helix740-7423
α-helix746-7516
α-helix753-7586

Molecules and chains

MoleculeChainsTypeLengthOrganismUniProt
DNA (5'-D(*AP*AP*AP*AP*AP*GP*AP*CP*5IUP*5IU*TP*GP*AP*AP*AP*AP*AP*5IUP*5IUP*5IUP*5IUP*T)-3')CDNA22
DNA (5'-D(*AP*AP*AP*AP*AP*TP*5IUP*5IUP*5IUP*5IUP*CP*AP*AP*AP*GP*TP*CP*TP*TP*TP*TP*T)-3')DDNA22
Protein (topoisomerase I)Aprotein591Homo sapiensP11387 (AlphaFold model)
Sequence of entity 1 (C), FASTA
>1A31_1 DNA (5'-D(*AP*AP*AP*AP*AP*GP*AP*CP*5IUP*5IU*TP*GP*AP*AP*AP*AP*AP*5IUP*5IUP*5IUP*5IUP*T)-3') (chains C)
AAAAAGACUUTGAAAAAUUUUT
Sequence of entity 2 (D), FASTA
>1A31_2 DNA (5'-D(*AP*AP*AP*AP*AP*TP*5IUP*5IUP*5IUP*5IUP*CP*AP*AP*AP*GP*TP*CP*TP*TP*TP*TP*T)-3') (chains D)
AAAAATUUUUCAAAGTCTTTTT
Sequence of entity 3 (A), FASTA
>1A31_3 PROTEIN (TOPOISOMERASE I) (chains A)
KPKNKDKDKKVPEPDNKKKKPKKEEEQKWKWWEEERYPEGIKWKFLEHKGPVFAPPYEPL
PENVKFYYDGKVMKLSPKAEEVATFFAKMLDHEYTTKEIFRKNFFKDWRKEMTNEEKNII
TNLSKCDFTQMSQYFKAQTEARKQMSKEEKLKIKEENEKLLKEYGFCIMDNHKERIANFK
IEPPGLFRGRGNHPKMGMLKRRIMPEDIIINCSKDAKVPSPPPGHKWKEVRHDNKVTWLV
SWTENIQGSIKYIMLNPSSRIKGEKDWQKYETARRLKKCVDKIRNQYREDWKSKEMKVRQ
RAVALYFIDKLALRAGNEKEEGETADTVGCCSLRVEHINLHPELDGQEYVVEFDFLGKDS
IRYYNKVPVEKRVFKNLQLFMENKQPEDDLFDRLNTGILNKHLQDLMEGLTAKVFRTYNA
SITLQQQLKELTAPDENIPAKILSYNRANRAVAILCNHQRAPPKTFEKSMMNLQTKIDAK
KEQLADARRDLKSAKADAKVMKDAKTKKVVESKKKAVQRLEEQLMKLEVQATDREENKQI
ALGTSKLNYLDPRITVAWCKKWGVPIEKIYNKTQREKFAWAIDMADEDYEF

Primary citation

Crystal structures of human topoisomerase I in covalent and noncovalent complexes with DNA. Redinbo, M.R., Stewart, L., Kuhn, P. et al. Science (1998) 279:1504-1513. DOI 10.1126/science.279.5356.1504 · PubMed

Other PDB entries of the same protein (UniProt P11387 (AlphaFold model), which also has an AlphaFold model), best resolution first:

Browse structure collections

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