Structure of PDB 1a36 Chain A

Receptor sequence

>1a36A (length=544) Species: 9606 (Homo sapiens)

IKWKFLEHKGPVFAPPYEPLPENVKFYYDGKVMKLSPKAEEVATFFAKML
DHEYTTKEIFRKNFFKDWRKEMTNEEKNIITNLSKCDFTQMSQYFKAQTE
ARKQMSKEEKLKIKEENEKLLKEYGFCIMDNHKERIANFKIEPPGLFRGR
GNHPKMGMLKRRIMPEDIIINCSKDAKVPSPPPGHKWKEVRHDNKVTWLV
SWTENIQGSIKYIMLNPSSRIKGEKDWQKYETARRLKKCVDKIRNQYRED
WKSKEMKVRQRAVALYFIDKLALRAGNEKEEGETADTVGCCSLRVEHINL
HPELDGQEYVVEFDFLGKDSIRYYNKVPVEKRVFKNLQLFMENKQPEDDL
FDRLNTGILNKHLQDLMEGLTAKVFRTYNASITLQQQLKELTAPDENIPA
KILSYNRANRAVAILCNHQEKSMMNLQTKIDAKKEQLADARRDLKSAKAD
AKVMKDAKTKKVVESKKKAVQRLEEQLMKLEVQATDREENKQIALGTSKL
NFLDPRITVAWCKKWGVPIEKIYNKTQREKFAWAIDMADEDYEF

3D structure

• PDB: 1a36 A model for the mechanism of human topoisomerase I.
• Chain: A
• Resolution: 2.8 Å

Enzymatic activity

• Enzyme Commision number: 5.6.2.1: DNA topoisomerase.

Interaction with ligand

Site #	Ligand	Ligand chain	Binding residues on receptor (original residue number in PDB)	Binding residues on receptor (residue number reindexed from 1)	Binding affinity
BS01	dna	A	H266 R362 R364 V410 T411 W412 I424 Y426 M428 K436 K439 K443 R488 K532 D533 K587 R590 H632 Q633 K650 T718 N722 F723	H52 R148 R150 V196 T197 W198 I210 Y212 M214 K222 K225 K229 R274 K318 D319 K373 R376 H418 Q419 K429 T497 N501 F502
BS02	dna	A	E356 G363 R364 H367 K374 K425 R488 A489 G490 N491 K493 T501 K532 D533 Q578 T585 A586 K587 R708 N745 K746 T747	E142 G149 R150 H153 K160 K211 R274 A275 G276 N277 K279 T287 K318 D319 Q364 T371 A372 K373 R487 N524 K525 T526

Gene Ontology

Molecular Function

• GO:0003677 DNA binding
• GO:0003917 DNA topoisomerase type I (single strand cut, ATP-independent) activity

Biological Process

• GO:0006265 DNA topological change

Cellular Component

• GO:0005694 chromosome

External links

• PDB: RCSB:1a36, PDBe:1a36, PDBj:1a36
• PDBsum: 1a36
• PubMed: 9488652
• UniProt: P11387|TOP1_HUMAN DNA topoisomerase 1 (Gene Name=TOP1)