1a31
HUMAN RECONSTITUTED DNA TOPOISOMERASE I IN COVALENT COMPLEX WITH A 22 BASE PAIR DNA DUPLEX
1. Protein Identity and Related Structures Protein Identity & Related Structures
No usable UniProt protein identity is available for this entry.
The relationship tables retain this entry's assembly and composition data, but cross-PDB links for the same protein cannot be established reliably without a unified protein identity.
Assembly Composition of the Current Entry
| Assembly | Physical composition | Protein state | 蛋白 / DNA / RNA / 其他Polymer | Data consistency |
|---|---|---|---|---|
| 1 | Protein–DNA | Monomer | 1 / 2 / 0 / 0 | Consistent with all polymers |
The page prioritizes protein identity, the current assembly, associated components, oligomeric state and cross-PDB links. Chain mapping and sequence ranges are retained as data evidence. Internal IDs, import timestamps and assembly operation expressions are maintenance fields and are not shown here.
2. Structure Basics 2. Structure Basics
| Entry ID entry_id | 1a31 |
| Deposition date deposition_date | 1998-01-27 |
| Structure title title | HUMAN RECONSTITUTED DNA TOPOISOMERASE I IN COVALENT COMPLEX WITH A 22 BASE PAIR DNA DUPLEX |
| Keywords keywords | TOPOISOMERASE I/DNA, DNA, TOPOISOMERASE I, ISOMERASE-DNA COMPLEX; ISOMERASE/DNA |
| Experimental Method method | X-RAY DIFFRACTION |
3. Official assembly/model SAXS Official SAXS Profiles
This page reads only the latest assembly calculations. Every curve maps to an explicit PDB entry, official biological assembly and coordinate model.
1a31__assembly_1__model_1
Assembly 1 · Model 1 · CRYSOL 4.1.3-1-20251215 (887e7ef)
1a31__assembly_1__model_1 | I(q)
1a31__assembly_1__model_1 | P(r) · Pending
| Rg（Guinier） | 26.32 Å |
| Rg (electron density) | 26.15 Å |
| Total Rg | 26.68 Å |
| Atom count | 4582 |
| Residues | 491 |
| Excluded volume | 79032 ų |
| Maximum q | 0.500 Å⁻¹ |
4. Crystallography and Experiment 4. Crystallography & Experiment
5. Entities and Polymers Entities & Polymers (4)
6. Fold Classification (SCOP + CATH) 6 domains
SCOP 2.08 (2 domains)
| Domain ID domain_id | d1a31a1 |
| Class class | d — Alpha and beta proteins (a+b) |
| Fold Fold fold | d.163 — DNA breaking-rejoining enzymes |
| Superfamily Superfamily superfamily | d.163.1 — DNA breaking-rejoining enzymes |
| Family Family family | d.163.1.2 — Eukaryotic DNA topoisomerase I, catalytic core |
| Domain ID domain_id | d1a31a2 |
| Class class | e — Multi-domain proteins (alpha and beta) |
| Fold Fold fold | e.15 — Eukaryotic DNA topoisomerase I, N-terminal DNA-binding fragment |
| Superfamily Superfamily superfamily | e.15.1 — Eukaryotic DNA topoisomerase I, N-terminal DNA-binding fragment |
| Family Family family | e.15.1.1 — Eukaryotic DNA topoisomerase I, N-terminal DNA-binding fragment |
CATH v4.4 (4 domains)
| Domain ID domain_id | 1a31A01 |
| Class class | 1 — Mainly Alpha |
| Architecture architecture | 10 — Orthogonal Bundle |
| Topology topology | 10 — Arc Repressor Mutant, subunit A |
| Homologous superfamily homologous superfamily | 41 — Yeast DNA topoisomerase - domain 1 |
| Domain ID domain_id | 1a31A02 |
| Class class | 2 — Mainly Beta |
| Architecture architecture | 170 — Beta Complex |
| Topology topology | 11 — DNA Topoisomerase I; domain 2 |
| Homologous superfamily homologous superfamily | 10 — DNA Topoisomerase I, domain 2 |
| Domain ID domain_id | 1a31A03 |
| Class class | 3 — Alpha Beta |
| Architecture architecture | 90 — Alpha-Beta Complex |
| Topology topology | 15 — Topoisomerase I; Chain A, domain 3 |
| Homologous superfamily homologous superfamily | 10 — Topoisomerase I; Chain A, domain 3 |
| Domain ID domain_id | 1a31A04 |
| Class class | 1 — Mainly Alpha |
| Architecture architecture | 10 — Orthogonal Bundle |
| Topology topology | 132 — Topoisomerase I; Chain A, domain 4 |
| Homologous superfamily homologous superfamily | 10 — |