SAXSdb — 3sir

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1. Protein Identity and Related Structures Protein Identity & Related Structures

Caspase

Drosophila melanogaster

State in the Current Structure

Assembly	Physical composition	Protein state	Molecular copy count	Associated components	Data consistency
1	Protein homooligomer	Homooligomer	Protein 2	water × 1	Consistent with protein count
2	Protein homooligomer	Homooligomer	Protein 2	No other associated polymer	Consistent with protein count

Other States of the Same Protein in the Database

View Construct and Data Evidence

UniProt name	ICE_DROME
Isoform	—
PDB entities	1
Chains and sequence ranges	Author chain A； PDBConstruct 5–259； UniProt 78–332 Author chain B； PDBConstruct 5–259； UniProt 78–332 Author chain C； PDBConstruct 5–259； UniProt 78–332 Author chain D； PDBConstruct 5–259； UniProt 78–332

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.

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2. Structure Basics 2. Structure Basics

Entry ID entry_id	3sir
Deposition date deposition_date	2011-06-20
Structure title title	Crystal Structure of drICE
Keywords keywords	caspase, HYDROLASE; HYDROLASE
Experimental Method method	X-RAY DIFFRACTION

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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.

3sir__assembly_1__model_1

Assembly 1 · Model 1 · CRYSOL 4.1.3-1-20251215 (887e7ef)

Download this curve (.dat)

3sir__assembly_1__model_1 | I(q)

100 plotted points; both axes use logarithmic scales.

3sir__assembly_1__model_1 | P(r) · Pending

P(r) will be calculated and displayed separately for the same assembly/model.

Rg（Guinier）	22.70 Å
Rg (electron density)	21.12 Å
Total Rg	22.09 Å
Atom count	3104
Residues	386
Excluded volume	55471 Å³
Maximum q	0.500 Å⁻¹

Assembly	Model	Structure unit	Oligomeric description	Status	CRYSOL	Actions
1	1	`3sir__assembly_1__model_1`	dimeric （2）	Success	4.1.3-1-20251215 (887e7ef)	View Download
2	1	`3sir__assembly_2__model_1`	dimeric （2）	Success	4.1.3-1-20251215 (887e7ef)	View Download

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4. Crystallography and Experiment 4. Crystallography & Experiment

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5. Entities and Polymers Entities & Polymers (2)

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6. Fold Classification (SCOP + CATH) 8 domains

SCOP 2.08 (4 domains)

Domain ID domain_id	d3sira_
Class class	c — Alpha and beta proteins (a/b)
Fold Fold fold	c.17 — Caspase-like
Superfamily Superfamily superfamily	c.17.1 — Caspase-like
Family Family family	c.17.1.1 — Caspase catalytic domain

Domain ID domain_id	d3sirb_
Class class	c — Alpha and beta proteins (a/b)
Fold Fold fold	c.17 — Caspase-like
Superfamily Superfamily superfamily	c.17.1 — Caspase-like
Family Family family	c.17.1.1 — Caspase catalytic domain

Domain ID domain_id	d3sirc_
Class class	c — Alpha and beta proteins (a/b)
Fold Fold fold	c.17 — Caspase-like
Superfamily Superfamily superfamily	c.17.1 — Caspase-like
Family Family family	c.17.1.1 — Caspase catalytic domain

Domain ID domain_id	d3sird_
Class class	c — Alpha and beta proteins (a/b)
Fold Fold fold	c.17 — Caspase-like
Superfamily Superfamily superfamily	c.17.1 — Caspase-like
Family Family family	c.17.1.1 — Caspase catalytic domain

CATH v4.4 (4 domains)

Domain ID domain_id	3sirA00
Class class	3 — Alpha Beta
Architecture architecture	40 — 3-Layer(aba) Sandwich
Topology topology	50 — Rossmann fold
Homologous superfamily homologous superfamily	1460 —

Domain ID domain_id	3sirB00
Class class	3 — Alpha Beta
Architecture architecture	40 — 3-Layer(aba) Sandwich
Topology topology	50 — Rossmann fold
Homologous superfamily homologous superfamily	1460 —

Domain ID domain_id	3sirC00
Class class	3 — Alpha Beta
Architecture architecture	40 — 3-Layer(aba) Sandwich
Topology topology	50 — Rossmann fold
Homologous superfamily homologous superfamily	1460 —

Domain ID domain_id	3sirD00
Class class	3 — Alpha Beta
Architecture architecture	40 — 3-Layer(aba) Sandwich
Topology topology	50 — Rossmann fold
Homologous superfamily homologous superfamily	1460 —

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Unit-cell length a length_a	56.025 Å
Unit-cell length b length_b	56.025 Å
Unit-cell length c length_c	287.441 Å
Unit-cell angle α angle_alpha	90.00 °
Unit-cell angle β angle_beta	90.00 °
Unit-cell angle γ angle_gamma	120.00 °
Molecules per unit cell Z z_pdb	12

Space group space_group	P 31
Space-group number int_tables_number	144
Crystal system crystal_system	—

Resolution resolution	2.680 Å
Low-resolution limit resolution_low	45.970 Å
R factor r_factor	0.1684
R_work r_work	0.1651
R_free r_free	0.2352

Description description	Caspase
Molecular weight formula_weight	29545.6 kDa
EC 编号 ec_number	3.4.22.-
Source method src_method	man
Copy count entity_count	4

Polymer type type	polypeptide(L)
Chain IDs strand_id	A,B,C,D
Atom count atom_count	5766

Crystal Structure of drICE

1. Protein Identity and Related Structures Protein Identity & Related Structures

Caspase

State in the Current Structure

Other States of the Same Protein in the Database

2. Structure Basics 2. Structure Basics

3. Official assembly/model SAXS Official SAXS Profiles

3sir__assembly_1__model_1

3sir__assembly_1__model_1 | I(q)

3sir__assembly_1__model_1 | P(r) · Pending

4. Crystallography and Experiment 4. Crystallography & Experiment

Unit cell Unit Cell

Symmetry Symmetry

Refinement Refinement

Diffraction experiment Diffraction

5. Entities and Polymers Entities & Polymers (2)

Entity 1 Entity 1 polymer

Polymer Polymer

Source Source

Entity 2 Entity 2 water

6. Fold Classification (SCOP + CATH) 8 domains

SCOP 2.08 (4 domains)

CATH v4.4 (4 domains)

7. Citations (1)

Source organism organism	Drosophila melanogaster
Common name common_name	Fruit fly
NCBI taxonomy ID ncbi_taxonomy_id	7227
Host organism host_organism	Escherichia coli

Description description	water
Molecular weight formula_weight	18.0 kDa
Source method src_method	nat
Copy count entity_count	3

Crystal Structure of drICE

1. Protein Identity and Related Structures Protein Identity & Related Structures

Caspase

State in the Current Structure

Other States of the Same Protein in the Database

Monomer

Homodimer

Homotetramer

Other homooligomers

Heteromeric or nucleic-acid complex

2. Structure Basics 2. Structure Basics

3. Official assembly/model SAXS Official SAXS Profiles

3sir__assembly_1__model_1

3sir__assembly_1__model_1 | I(q)

3sir__assembly_1__model_1 | P(r) · Pending

4. Crystallography and Experiment 4. Crystallography & Experiment

Unit cell Unit Cell

Symmetry Symmetry

Refinement Refinement

Diffraction experiment Diffraction

5. Entities and Polymers Entities & Polymers (2)

Entity 1 Entity 1 polymer

Polymer Polymer

Source Source

Entity 2 Entity 2 water

6. Fold Classification (SCOP + CATH) 8 domains

SCOP 2.08 (4 domains)

CATH v4.4 (4 domains)

7. Citations (1)