SAXSdb — 1kaw

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

SINGLE-STRANDED DNA BINDING PROTEIN

OrganismNot specified

State in the Current Structure

Assembly	Physical composition	Protein state	Molecular copy count	Associated components	Data consistency
1	Protein homooligomer	Homooligomer	Protein 4	water × 4	Consistent with protein count

Other States of the Same Protein in the Database

View Construct and Data Evidence

UniProt name	SSB_ECOLI
Isoform	—
PDB entities	1
Chains and sequence ranges	Author chain A； PDBConstruct 1–135； UniProt 1–135 Author chain B； PDBConstruct 1–135； UniProt 1–135 Author chain C； PDBConstruct 1–135； UniProt 1–135 Author chain D； PDBConstruct 1–135； UniProt 1–135

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	1kaw
Deposition date deposition_date	1996-12-06
Structure title title	STRUCTURE OF SINGLE STRANDED DNA BINDING PROTEIN (SSB)
Keywords keywords	DNA-BINDING PROTEIN, SINGLE STRANDED DNA BINDING PROTEIN, SSB, DNA BINDING PROTEIN; DNA BINDING PROTEIN
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.

1kaw__assembly_1__model_1

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

Download this curve (.dat)

1kaw__assembly_1__model_1 | I(q)

100 plotted points; both axes use logarithmic scales.

1kaw__assembly_1__model_1 | P(r) · Pending

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

Rg（Guinier）	25.96 Å
Rg (electron density)	25.54 Å
Total Rg	26.45 Å
Atom count	3032
Residues	384
Excluded volume	53755 Å³
Maximum q	0.500 Å⁻¹

Assembly	Model	Structure unit	Oligomeric description	Status	CRYSOL	Actions
1	1	`1kaw__assembly_1__model_1`	tetrameric （4）	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	d1kawa_
Class class	b — All beta proteins
Fold Fold fold	b.40 — OB-fold
Superfamily Superfamily superfamily	b.40.4 — Nucleic acid-binding proteins
Family Family family	b.40.4.3 — Single strand DNA-binding domain, SSB

Domain ID domain_id	d1kawb_
Class class	b — All beta proteins
Fold Fold fold	b.40 — OB-fold
Superfamily Superfamily superfamily	b.40.4 — Nucleic acid-binding proteins
Family Family family	b.40.4.3 — Single strand DNA-binding domain, SSB

Domain ID domain_id	d1kawc_
Class class	b — All beta proteins
Fold Fold fold	b.40 — OB-fold
Superfamily Superfamily superfamily	b.40.4 — Nucleic acid-binding proteins
Family Family family	b.40.4.3 — Single strand DNA-binding domain, SSB

Domain ID domain_id	d1kawd_
Class class	b — All beta proteins
Fold Fold fold	b.40 — OB-fold
Superfamily Superfamily superfamily	b.40.4 — Nucleic acid-binding proteins
Family Family family	b.40.4.3 — Single strand DNA-binding domain, SSB

CATH v4.4 (4 domains)

Domain ID domain_id	1kawA00
Class class	2 — Mainly Beta
Architecture architecture	40 — Beta Barrel
Topology topology	50 — OB fold (Dihydrolipoamide Acetyltransferase, E2P)
Homologous superfamily homologous superfamily	140 — Nucleic acid-binding proteins

Domain ID domain_id	1kawB00
Class class	2 — Mainly Beta
Architecture architecture	40 — Beta Barrel
Topology topology	50 — OB fold (Dihydrolipoamide Acetyltransferase, E2P)
Homologous superfamily homologous superfamily	140 — Nucleic acid-binding proteins

Domain ID domain_id	1kawC00
Class class	2 — Mainly Beta
Architecture architecture	40 — Beta Barrel
Topology topology	50 — OB fold (Dihydrolipoamide Acetyltransferase, E2P)
Homologous superfamily homologous superfamily	140 — Nucleic acid-binding proteins

Domain ID domain_id	1kawD00
Class class	2 — Mainly Beta
Architecture architecture	40 — Beta Barrel
Topology topology	50 — OB fold (Dihydrolipoamide Acetyltransferase, E2P)
Homologous superfamily homologous superfamily	140 — Nucleic acid-binding proteins

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Unit-cell length a length_a	58.080 Å
Unit-cell length b length_b	105.850 Å
Unit-cell length c length_c	90.240 Å
Unit-cell angle α angle_alpha	90.00 °
Unit-cell angle β angle_beta	99.00 °
Unit-cell angle γ angle_gamma	90.00 °
Molecules per unit cell Z z_pdb	16

Space group space_group	C 1 2 1
Space-group number int_tables_number	5
Crystal system crystal_system	—

Resolution resolution	2.900 Å
Low-resolution limit resolution_low	8.000 Å
R factor r_factor	0.2210
R_work r_work	0.2210
R_free r_free	0.2890

Description description	SINGLE-STRANDED DNA BINDING PROTEIN
Molecular weight formula_weight	14480.2 kDa
Source method src_method	nat
Copy count entity_count	4

Polymer type type	polypeptide(L)
Chain IDs strand_id	A,B,C,D
Atom count atom_count	3067

STRUCTURE OF SINGLE STRANDED DNA BINDING PROTEIN (SSB)

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

SINGLE-STRANDED DNA BINDING PROTEIN

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

1kaw__assembly_1__model_1

1kaw__assembly_1__model_1 | I(q)

1kaw__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

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)

Description description	water
Molecular weight formula_weight	18.0 kDa
Source method src_method	nat
Copy count entity_count	35

STRUCTURE OF SINGLE STRANDED DNA BINDING PROTEIN (SSB)

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

SINGLE-STRANDED DNA BINDING PROTEIN

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

1kaw__assembly_1__model_1

1kaw__assembly_1__model_1 | I(q)

1kaw__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

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)