SAXSdb — 1ctx

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

ALPHA-COBRATOXIN

Naja siamensis

State in the Current Structure

Assembly	Oligomeric State	Construct	Mutations and Modifications	Ligands, Ions and Associated Components	Method and Experimental Conditions	Structure Quality
1	Protein homooligomer Homooligomer Protein × 2 PDB declaration: dimeric（2） Consistent with protein copy count	Chain A； UniProt 1–71	Not recorded	No other associated polymer	X-RAY DIFFRACTION mmCIF provides none of the parsed experimental conditions	Resolution 2.80 Å

Other States of the Same Protein in the Database

Each row is a biological assembly of the same UniProt protein in another PDB entry. The “Difference from current entry” column identifies evidence-level differences; no tag means the currently parsed fields agree.

Other PDB	Difference from Current Entry 1CTX	Assembly / Oligomeric State	Construct	Mutations and Modifications	Ligands, Ions and Non-polymers	Method and Experimental Conditions	Structure Quality
1LXG Solution structure of alpha-cobratoxin complexed with a cognate peptide (structure ensemble) Deposited 2002-06-05	Different oligomeric state Different experimental method Different experimental conditions Different structure-quality metrics	Assembly 1 Protein heterocomplex Heteromer；Protein × 2 PDB declaration: dimeric	Chain A 1–71（71 aa）	Not recorded	No recorded non-water small molecule	SOLUTION NMR NMR measurement conditions pH 4；308 K；Pressure AMBIENT NMR sample composition 1.6 mM alpha-cobratoxin/alpha18-mer complex, alpha18-mer is U-15N, 50 mM perdeuterated potassium acetate buffer (pH 4.0) with 5% D2O and 0.05% sodium azide \| 95% H2O/5% D2O	Resolution not provided
1LXH Solution structure of alpha-cobratoxin complexed with a cognate peptide (minimized average structure) Deposited 2002-06-05	Different oligomeric state Different experimental method Different experimental conditions Different structure-quality metrics	Assembly 1 Protein heterocomplex Heteromer；Protein × 2 PDB declaration: dimeric	Chain A 1–71（71 aa）	Not recorded	No recorded non-water small molecule	SOLUTION NMR NMR measurement conditions pH 4；308 K；Ionic strength (raw mmCIF value) NULL；Pressure AMBIENT NMR sample composition 1.6 mM alpha-cobratoxin/alpha18-mer complex, alpha18-mer is U-15N, 50 mM perdeuterated potassium acetate buffer (pH 4.0) with 5% D2O and 0.05% sodium azide \| 95% H2O/5% D2O	Resolution not provided
1YI5 Crystal structure of the a-cobratoxin-AChBP complex Deposited 2005-01-11	Different construct Different mutation/modification Different oligomeric state Different experimental conditions Different structure-quality metrics	Assembly 1 Protein heterocomplex Heteromer；Protein × 10 PDB declaration: decameric	Chain F 1–71（71 aa） Chain G 1–71（71 aa） Chain H 1–71（71 aa） Chain I 1–71（71 aa） Chain J 1–71（71 aa）	Not recorded	No recorded non-water small molecule	X-RAY DIFFRACTION X-ray crystallization conditions VAPOR DIFFUSION, HANGING DROP；pH 8.5；277 K；0.9M NA-CITRATE, pH 8.5, VAPOR DIFFUSION, HANGING DROP, temperature 277K	Resolution 4.20 Å R-free 0.378
4AEA Dimeric alpha-cobratoxin X-ray structure: Localization of intermolecular disulfides and possible mode of binding to nicotinic acetylcholine receptors Deposited 2012-01-09	Different ligand/ion Different experimental conditions Different structure-quality metrics	Assembly 1 Protein homooligomer Homooligomer；Protein × 2 PDB declaration: dimeric	Chain A 1–71（71 aa）	Not recorded	GLY GLYCINE × 2 MPD (4S)-2-METHYL-2,4-PENTANEDIOL × 2	X-RAY DIFFRACTION X-ray crystallization conditions pH 2；60% (V/V) 2-METHYL-2,4- PENTANEDIOL, 0.1 M GLYCINE-HCL PH 2	Resolution 1.94 Å R-free 0.251
4AEA Dimeric alpha-cobratoxin X-ray structure: Localization of intermolecular disulfides and possible mode of binding to nicotinic acetylcholine receptors Deposited 2012-01-09	Different experimental conditions Different structure-quality metrics	Assembly 2 Protein homooligomer Homooligomer；Protein × 2 PDB declaration: dimeric	Chain B 1–71（71 aa）	Not recorded	No recorded non-water small molecule	X-RAY DIFFRACTION X-ray crystallization conditions pH 2；60% (V/V) 2-METHYL-2,4- PENTANEDIOL, 0.1 M GLYCINE-HCL PH 2	Resolution 1.94 Å R-free 0.251
6ZFM Structure of alpha-Cobratoxin with a peptide inhibitor Deposited 2020-06-17	Different construct Different mutation/modification Different oligomeric state Different ligand/ion Different experimental conditions Different structure-quality metrics	Assembly 1 Protein heterocomplex Heteromer；Protein × 6 PDB declaration: hexameric	Chain A 1–71（71 aa） Chain B 1–71（71 aa） Chain D 1–71（71 aa） Chain E 1–71（71 aa）	Not recorded	QJE 3-[2-[2-[2-[2-[2-(2-azanylethoxy)ethoxy]ethoxy]ethoxy]ethoxy]ethoxy]propan-1-ol × 2 1PE PENTAETHYLENE GLYCOL × 1	X-RAY DIFFRACTION X-ray crystallization conditions VAPOR DIFFUSION；293 K；0.1 M Carboxylic acids (sodium formate / ammonium acetate / sodium citrate / sodium potassium tartrate / sodium oxamate), 0.1 M HEPES / MOPS pH7.5, 30.0 % v/v PEG 500 MME / PEG 20000	Resolution 1.90 Å R-free 0.230
7PC0 GABA-A receptor bound by a-Cobratoxin Deposited 2021-08-03	Different construct Different mutation/modification Different oligomeric state Different ligand/ion Different experimental method Different experimental conditions Different structure-quality metrics	Assembly 1 Other combination Heteromer；Protein × 8 PDB declaration: octameric	Chain K 1–71（71 aa） Chain L 1–71（71 aa）	Not recorded	NAG 2-acetamido-2-deoxy-beta-D-glucopyranose × 4 HSM HISTAMINE × 1 ZN ZINC ION × 1 HEX HEXANE × 1	ELECTRON MICROSCOPY cryo-EM buffer pH 7.4 cryo-EM vitrification conditions Cryogen ETHANE	Resolution 3.00 Å
7ULG recombinant alpha cobra toxin Deposited 2022-04-04	Different oligomeric state Different experimental conditions Different structure-quality metrics	Assembly 1 Protein monomer Monomer；Protein × 1 PDB declaration: monomeric	Chain A 1–71（71 aa）	Not recorded	No recorded non-water small molecule	X-RAY DIFFRACTION X-ray crystallization conditions VAPOR DIFFUSION, HANGING DROP；pH 7.9；291.15 K；110 mg/ml in 200 mM NH4Ac (pH 7.0/25 DC), 1:1 with 0.1 M HEPES (pH 7.9), 30% Jeffamine M-600 (pH 7.0), 18 DC	Resolution 1.57 Å R-free 0.181
7ULG recombinant alpha cobra toxin Deposited 2022-04-04	Different oligomeric state Different ligand/ion Different experimental conditions Different structure-quality metrics	Assembly 2 Protein monomer Monomer；Protein × 1 PDB declaration: monomeric	Chain B 1–71（71 aa）	Not recorded	EPE 4-(2-HYDROXYETHYL)-1-PIPERAZINE ETHANESULFONIC ACID × 1	X-RAY DIFFRACTION X-ray crystallization conditions VAPOR DIFFUSION, HANGING DROP；pH 7.9；291.15 K；110 mg/ml in 200 mM NH4Ac (pH 7.0/25 DC), 1:1 with 0.1 M HEPES (pH 7.9), 30% Jeffamine M-600 (pH 7.0), 18 DC	Resolution 1.57 Å R-free 0.181
7ULG recombinant alpha cobra toxin Deposited 2022-04-04	Different oligomeric state Different ligand/ion Different experimental conditions Different structure-quality metrics	Assembly 3 Protein monomer Monomer；Protein × 1 PDB declaration: monomeric	Chain C 1–71（71 aa）	Not recorded	ACT ACETATE ION × 1	X-RAY DIFFRACTION X-ray crystallization conditions VAPOR DIFFUSION, HANGING DROP；pH 7.9；291.15 K；110 mg/ml in 200 mM NH4Ac (pH 7.0/25 DC), 1:1 with 0.1 M HEPES (pH 7.9), 30% Jeffamine M-600 (pH 7.0), 18 DC	Resolution 1.57 Å R-free 0.181
7ULG recombinant alpha cobra toxin Deposited 2022-04-04	Different oligomeric state Different experimental conditions Different structure-quality metrics	Assembly 4 Protein monomer Monomer；Protein × 1 PDB declaration: monomeric	Chain D 1–71（71 aa）	Not recorded	No recorded non-water small molecule	X-RAY DIFFRACTION X-ray crystallization conditions VAPOR DIFFUSION, HANGING DROP；pH 7.9；291.15 K；110 mg/ml in 200 mM NH4Ac (pH 7.0/25 DC), 1:1 with 0.1 M HEPES (pH 7.9), 30% Jeffamine M-600 (pH 7.0), 18 DC	Resolution 1.57 Å R-free 0.181
9BK5 Structure of LNG binder complex Deposited 2024-04-26	Different oligomeric state Different experimental conditions Different structure-quality metrics	Assembly 1 Protein heterocomplex Heteromer；Protein × 2 PDB declaration: dimeric	Chain B 1–71（71 aa）	Not recorded	No recorded non-water small molecule	X-RAY DIFFRACTION X-ray crystallization conditions VAPOR DIFFUSION, SITTING DROP；293 K；1.5 M Ammonium Sulfate and 25% (v/v) glycerol	Resolution 2.68 Å R-free 0.268
9FYT mAbs in complex with cobratoxin at pH 4.5 Deposited 2024-07-03	Different construct Different mutation/modification Different oligomeric state Different ligand/ion Different experimental conditions Different structure-quality metrics	Assembly 1 Protein heterocomplex Heteromer；Protein × 6 PDB declaration: hexameric	Chain A 1–71（71 aa） Chain B 1–71（71 aa）	Not recorded	CL CHLORIDE ION × 3 GOL GLYCEROL × 5 SO4 SULFATE ION × 1 NA SODIUM ION × 2	X-RAY DIFFRACTION X-ray crystallization conditions VAPOR DIFFUSION, HANGING DROP；pH 4.5；293 K；0.1 M Bis-Tris pH 6.5, 0.2 M Ammonium Sulfate, 25% PEG 3350	Resolution 1.55 Å R-free 0.237
9GCN Co-crystal VHH (TPL1158_01_C09) - alpha-cobratoxin (Naja kaouthia) Deposited 2024-08-02	Different oligomeric state Different experimental conditions Different structure-quality metrics	Assembly 1 Protein heterocomplex Heteromer；Protein × 2 PDB declaration: dimeric	Chain Z 1–71（71 aa）	Not recorded	No recorded non-water small molecule	X-RAY DIFFRACTION X-ray crystallization conditions VAPOR DIFFUSION, SITTING DROP；298.15 K；1.5 mM Tris and 6.5 mM NaCl, 17% (w/v) PEG1500. 20% (v/v) glycerol as cryopreservative.	Resolution 3.00 Å R-free 0.292
9GCN Co-crystal VHH (TPL1158_01_C09) - alpha-cobratoxin (Naja kaouthia) Deposited 2024-08-02	Different oligomeric state Different experimental conditions Different structure-quality metrics	Assembly 2 Protein heterocomplex Heteromer；Protein × 2 PDB declaration: dimeric	Chain Y 1–71（71 aa）	Not recorded	No recorded non-water small molecule	X-RAY DIFFRACTION X-ray crystallization conditions VAPOR DIFFUSION, SITTING DROP；298.15 K；1.5 mM Tris and 6.5 mM NaCl, 17% (w/v) PEG1500. 20% (v/v) glycerol as cryopreservative.	Resolution 3.00 Å R-free 0.292
9GCN Co-crystal VHH (TPL1158_01_C09) - alpha-cobratoxin (Naja kaouthia) Deposited 2024-08-02	Different oligomeric state Different experimental conditions Different structure-quality metrics	Assembly 3 Protein heterocomplex Heteromer；Protein × 2 PDB declaration: dimeric	Chain V 1–71（71 aa）	Not recorded	No recorded non-water small molecule	X-RAY DIFFRACTION X-ray crystallization conditions VAPOR DIFFUSION, SITTING DROP；298.15 K；1.5 mM Tris and 6.5 mM NaCl, 17% (w/v) PEG1500. 20% (v/v) glycerol as cryopreservative.	Resolution 3.00 Å R-free 0.292
9GCN Co-crystal VHH (TPL1158_01_C09) - alpha-cobratoxin (Naja kaouthia) Deposited 2024-08-02	Different oligomeric state Different experimental conditions Different structure-quality metrics	Assembly 4 Protein heterocomplex Heteromer；Protein × 2 PDB declaration: dimeric	Chain X 1–71（71 aa）	Not recorded	No recorded non-water small molecule	X-RAY DIFFRACTION X-ray crystallization conditions VAPOR DIFFUSION, SITTING DROP；298.15 K；1.5 mM Tris and 6.5 mM NaCl, 17% (w/v) PEG1500. 20% (v/v) glycerol as cryopreservative.	Resolution 3.00 Å R-free 0.292
9HUO A01 mAbs bound to cobratoxin at pH 5.5 Deposited 2024-12-23	Different oligomeric state Different ligand/ion Different experimental conditions Different structure-quality metrics	Assembly 1 Protein heterocomplex Heteromer；Protein × 3 PDB declaration: trimeric	Chain A 1–71（71 aa）	Not recorded	GOL GLYCEROL × 2 CL CHLORIDE ION × 1 K POTASSIUM ION × 1	X-RAY DIFFRACTION X-ray crystallization conditions VAPOR DIFFUSION；pH 5.5；293 K；25% PEG3350, 0.1M Bis-Tris pH5.5, 0.25 M AmS	Resolution 1.60 Å R-free 0.225
9HUO A01 mAbs bound to cobratoxin at pH 5.5 Deposited 2024-12-23	Different oligomeric state Different ligand/ion Different experimental conditions Different structure-quality metrics	Assembly 2 Protein heterocomplex Heteromer；Protein × 3 PDB declaration: trimeric	Chain B 1–71（71 aa）	Not recorded	GOL GLYCEROL × 3 NA SODIUM ION × 2 SO4 SULFATE ION × 1	X-RAY DIFFRACTION X-ray crystallization conditions VAPOR DIFFUSION；pH 5.5；293 K；25% PEG3350, 0.1M Bis-Tris pH5.5, 0.25 M AmS	Resolution 1.60 Å R-free 0.225
9HXO A01 mAbs bound to cobratoxin at pH 6.0 Deposited 2025-01-07	Different oligomeric state Different ligand/ion Different experimental conditions Different structure-quality metrics	Assembly 1 Protein monomer Monomer；Protein × 1 PDB declaration: monomeric	Chain A 1–71（71 aa）	Not recorded	CL CHLORIDE ION × 1	X-RAY DIFFRACTION X-ray crystallization conditions VAPOR DIFFUSION；pH 6；293 K；25% PEG3350, 0.1M Bis-Tris pH 6.0, 0.3 M Ammonium Sulphate	Resolution 1.49 Å R-free 0.248
9HXO A01 mAbs bound to cobratoxin at pH 6.0 Deposited 2025-01-07	Different oligomeric state Different ligand/ion Different experimental conditions Different structure-quality metrics	Assembly 2 Protein monomer Monomer；Protein × 1 PDB declaration: monomeric	Chain B 1–71（71 aa）	Not recorded	GOL GLYCEROL × 1 TRS 2-AMINO-2-HYDROXYMETHYL-PROPANE-1,3-DIOL × 1	X-RAY DIFFRACTION X-ray crystallization conditions VAPOR DIFFUSION；pH 6；293 K；25% PEG3350, 0.1M Bis-Tris pH 6.0, 0.3 M Ammonium Sulphate	Resolution 1.49 Å R-free 0.248

12 other PDB entries and 21 assemblies. Open the comparison page and filter oligomeric states

View Construct and Data Evidence

UniProt name	NXL1_NAJKA
Isoform	—
PDB entities	1
Chains and sequence ranges	Author chain A； PDBConstruct 1–71； UniProt 1–71

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	1ctx
Deposition date deposition_date	1982-04-08
Structure title title	THREE-DIMENSIONAL STRUCTURE OF THE-LONG-NEUROTOXIN FROM COBRA VENOM
Keywords keywords	TOXIN; TOXIN
Experimental Method method	X-RAY DIFFRACTION

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3. SAXS Parameters (CRYSOL theoretical calculation) 3. SAXS Parameters (CRYSOL)

Radius of gyration Rg (Guinier) rg_guinier	13.45 Å
Radius of gyration Rg (electron density) rg_electron	12.54 Å
Forward intensity I(0) i0	1569360.00
Molecular weight molecular_weight	7835.0 kDa
Excluded volume excluded_volume	9575 Å³
Envelope volume envelope_volume	11176 Å³
Hydration-shell volume shell_volume	8176 Å³
Envelope diameter envelope_diameter	44.5 Å
Shell Rg shell_rg	17.31 Å
Envelope Rg envelope_rg	12.91 Å
Shape Rg shape_rg	12.53 Å
Total Rg total_rg	13.73 Å
Total atoms total_atoms	541
Residues n_residues	71
Spherical-harmonic order n_harmonics	20
q range q_range	— – 0.5000 Å⁻¹
Data points n_points	101
Shell type shell_type	directional
Solvent electron density solvent_density	0.3340 e/Å³
Shell contrast contrast_shell	0.0300 e/Å³
CRYSOL version crysol_version	4.1.3

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4. P(r) Distance Distribution (GNOM inversion) 4. P(r) Analysis (GNOM)

Maximum dimension Dmax dmax	46.4 Å
Rg (real space) rg_real	13.46 Å
Rg uncertainty (real space) rg_real_error	0.28 Å
I(0) (real space) i0_real	1.5690e+06
I(0) uncertainty (real space) i0_real_error	1.5810e+04
Rg (reciprocal space) rg_reciprocal	13.46 Å
I(0) (reciprocal space) i0_reciprocal	1569000.0000
Solution quality estimate total_estimate	0.6255
Solution quality rating solution_quality	REASONABLE a REASONABLE solution
P(r) peaks n_peaks	2
Primary peak position r_peak_primary	14.1 Å
Skewness Skewness skewness	0.354
Kurtosis Kurtosis kurtosis	-0.347
Angular range angular_range	— – 0.5000 Å⁻¹
Current regularization parameter α current_alpha	0.0000
Highest regularization parameter α highest_alpha	382100.0000
Real-space data points n_real_points	80
GNOM version gnom_version	4.1.3
Quality Criteria quality_criteria	AN1: 0.000; Oscil: 0.825; Stabil: 1.000; Sysdev: 0.256; Positv: 1.000; Valcen: 0.882; Smooth: 0.000

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5. Crystallography and Experiment 5. Crystallography & Experiment

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6. Entities and Polymers Entities & Polymers (1)

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7. Fold Classification (SCOP + CATH) 2 domains

SCOP 2.08 (1 domains)

Domain ID domain_id	d1ctxa_
Class class	g — Small proteins
Fold Fold fold	g.7 — Snake toxin-like
Superfamily Superfamily superfamily	g.7.1 — Snake toxin-like
Family Family family	g.7.1.1 — Snake venom toxins

CATH v4.4 (1 domains)

Domain ID domain_id	1ctxA00
Class class	2 — Mainly Beta
Architecture architecture	10 — Ribbon
Topology topology	60 — CD59
Homologous superfamily homologous superfamily	10 — CD59

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8. Citations (1)

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Unit-cell length a length_a	74.600 Å
Unit-cell length b length_b	74.600 Å
Unit-cell length c length_c	42.900 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 65 2 2
Space-group number int_tables_number	179
Crystal system crystal_system	—

Resolution resolution	2.800 Å
Low-resolution limit resolution_low	— Å
R factor r_factor	—
R_work r_work	—
R_free r_free	—

Description description	ALPHA-COBRATOXIN
Molecular weight formula_weight	7842.1 kDa
Source method src_method	man
Copy count entity_count	1

Polymer type type	polypeptide(L)
Chain IDs strand_id	A
Atom count atom_count	541

THREE-DIMENSIONAL STRUCTURE OF THE-LONG-NEUROTOXIN FROM COBRA VENOM

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

ALPHA-COBRATOXIN

State in the Current Structure

Other States of the Same Protein in the Database

SAXS scattering curve SAXS Profile

P(r) Distance Distribution P(r) Distribution

2. Structure Basics 2. Structure Basics

3. SAXS Parameters (CRYSOL theoretical calculation) 3. SAXS Parameters (CRYSOL)

4. P(r) Distance Distribution (GNOM inversion) 4. P(r) Analysis (GNOM)

5. Crystallography and Experiment 5. Crystallography & Experiment

Unit cell Unit Cell

Symmetry Symmetry

Refinement Refinement

6. Entities and Polymers Entities & Polymers (1)

Entity 1 Entity 1 polymer

Polymer Polymer

来源 Source

7. Fold Classification (SCOP + CATH) 2 domains

SCOP 2.08 (1 domains)

CATH v4.4 (1 domains)

8. Citations (1)

9. Files and Curves (10)

Files (7)

Curves (3)

来源生物 organism	Naja siamensis
NCBI Class编号 ncbi_taxonomy_id	84476

fit	/app/data/saxs_computation/ct/1ctx/1ctx.fit
pddf	/app/data/pr_computation/ct/1ctx/1ctx.pr.out
profile	/app/data/saxs_computation/ct/1ctx/1ctx.dat