PDBe 1k4t

X-ray diffraction
2.1Å resolution

HUMAN DNA TOPOISOMERASE I (70 KDA) IN COMPLEX WITH THE POISON TOPOTECAN AND COVALENT COMPLEX WITH A 22 BASE PAIR DNA DUPLEX

Released:
Primary publication:
The mechanism of topoisomerase I poisoning by a camptothecin analog.
Proc. Natl. Acad. Sci. U.S.A. 99 15387-92 (2002)
PMID: 12426403

Function and Biology Details

Structure analysis Details

Assembly composition:
hetero tetramer (preferred)
Entry contents:
1 distinct polypeptide molecule
3 distinct DNA molecules
Macromolecules (4 distinct):
DNA topoisomerase 1 Chain: A
Molecule details ›
Chain: A
Length: 592 amino acids
Theoretical weight: 70.25 KDa
Source organism: Homo sapiens
Expression system: Spodoptera frugiperda
UniProt:
  • Canonical: P11387 (Residues: 174-765; Coverage: 77%)
Gene name: TOP1
Sequence domains:
Structure domains:
5'-D(*AP*AP*AP*AP*AP*GP*AP*CP*TP*T)-3' Chain: B
Molecule details ›
Chain: B
Length: 10 nucleotides
Theoretical weight: 3.06 KDa
Source organism: Synthetic construct
Expression system: Not provided
5'-D(*(TGP)P*GP*AP*AP*AP*AP*AP*TP*TP*TP*TP*T)-3' Chain: C
Molecule details ›
Chain: C
Length: 12 nucleotides
Theoretical weight: 3.72 KDa
Source organism: Synthetic construct
Expression system: Not provided
5'-D(*AP*AP*AP*AP*AP*TP*TP*TP*TP*TP*CP*CP*AP*AP*GP*TP*CP*TP*TP*TP*TP*T)-3' Chain: D
Molecule details ›
Chain: D
Length: 22 nucleotides
Theoretical weight: 6.69 KDa
Source organism: Synthetic construct
Expression system: Not provided

Ligands and Environments


2 modified residues:

Experiments and Validation Details

Entry percentile scores
X-ray source: NSLS BEAMLINE X25
Spacegroup: P21
Unit cell:
a: 57.093Å b: 116.26Å c: 75.217Å
α: 90° β: 94.16° γ: 90°
R-values:
R R work R free
0.229 0.229 0.269
Expression systems:
  • Spodoptera frugiperda
  • Not provided