SAXSdb — 6cnn

▼

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

Intermediate conductance calcium-activated potassium channel protein 4

Homo sapiens

State in the Current Structure

Assembly	Physical composition	Protein state	Molecular copy count	Associated components	Data consistency
1	Protein heterocomplex	Heteromer	Protein 8	Calmodulin-1 × 4 （P0DP23） POTASSIUM ION × 4 (2S)-3-(hexadecanoyloxy)-2-[(9Z)-octadec-9-enoyloxy]propyl 2-(trimethylammonio)ethyl phosphate × 4 DODECYL-BETA-D-MALTOSIDE × 8 CALCIUM ION × 12	Consistent with protein count

Other States of the Same Protein in the Database

View Construct and Data Evidence

UniProt name	KCNN4_HUMAN
Isoform	—
PDB entities	1
Chains and sequence ranges	Author chain A； PDBConstruct 1–427； UniProt 1–427 Author chain B； PDBConstruct 1–427； UniProt 1–427 Author chain C； PDBConstruct 1–427； UniProt 1–427 Author chain D； PDBConstruct 1–427； UniProt 1–427

Calmodulin-1

Homo sapiens

UniProt P0DP23

State in the Current Structure

Assembly	Physical composition	Protein state	Molecular copy count	Associated components	Data consistency
1	Protein heterocomplex	Heteromer	Protein 8	Intermediate conductance calcium-activated potassium channel protein 4 × 4 （O15554） POTASSIUM ION × 4 (2S)-3-(hexadecanoyloxy)-2-[(9Z)-octadec-9-enoyloxy]propyl 2-(trimethylammonio)ethyl phosphate × 4 DODECYL-BETA-D-MALTOSIDE × 8 CALCIUM ION × 12	Consistent with protein count

Other States of the Same Protein in the Database

View Construct and Data Evidence

UniProt name	CALM1_HUMAN
Isoform	—
PDB entities	2
Chains and sequence ranges	Author chain E； PDBConstruct 1–149； UniProt 1–149 Author chain F； PDBConstruct 1–149； UniProt 1–149 Author chain G； PDBConstruct 1–149； UniProt 1–149 Author chain H； PDBConstruct 1–149； UniProt 1–149

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	6cnn
Deposition date deposition_date	2018-03-08
Structure title title	Cryo-EM structure of the human SK4/calmodulin channel complex in the Ca2+ bound state I
Keywords keywords	ion channel, neuroscience, calmodulin, MEMBRANE PROTEIN; MEMBRANE PROTEIN
Experimental Method method	ELECTRON MICROSCOPY

▼

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.

6cnn__assembly_1__model_1

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

Download this curve (.dat)

6cnn__assembly_1__model_1 | I(q)

100 plotted points; both axes use logarithmic scales.

6cnn__assembly_1__model_1 | P(r) · Pending

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

Rg（Guinier）	42.91 Å
Rg (electron density)	41.81 Å
Total Rg	42.06 Å
Atom count	15740
Residues	2024
Excluded volume	283970 Å³
Maximum q	0.500 Å⁻¹

Assembly	Model	Structure unit	Oligomeric description	Status	CRYSOL	Actions
1	1	`6cnn__assembly_1__model_1`	octameric （8）	Success	4.1.3-1-20251215 (887e7ef)	View Download

▶

4. Crystallography and Experiment 4. Crystallography & Experiment

▶

5. Entities and Polymers Entities & Polymers (6)

Entity 1 Entity 1 polymer

Description description	Intermediate conductance calcium-activated potassium channel protein 4
Molecular weight formula_weight	47758.5 kDa
Source method src_method	man
Copy count entity_count	4

Polymer Polymer

Polymer type type	polypeptide(L)
Chain IDs strand_id	A,B,C,D
Atom count atom_count	15740

MGGDLVLGLGALRRRKRLLEQEKSLAGWALVLAGTGIGLMVLHAEMLWFGGCSWALYLFLVKCTISISTFLLLCLIVAFHAKEVQLFMTDNGLRDWRVALTGRQAAQIVLELVVCGLHPAPVRGPPCVQDLGAPLTSPQPWPGFLGQGEALLSLAMLLRLYLVPRAVLLRSGVLLNASYRSIGALNQVRFRHWFVAKLYMNTHPGRLLLGLTLGLWLTTAWVLSVAERQAVNATGHLSDTLWLIPITFLTIGYGDVVPGTMWGKIVCLCTGVMGVCCTALLVAVVARKLEFNKAEKHVHNFMMDIQYTKEMKESAARVLQEAWMFYKHTRRKESHAARRHQRKLLAAINAFRQVRLKHRKLREQVNSMVDISKMHMILYDLQQNLSSSHRALEKQIDTLAGKLDALTELLSTALGPRQLPEPSQQSK

Source Source

Source organism organism	Homo sapiens
Common name common_name	Human
NCBI taxonomy ID ncbi_taxonomy_id	9606
Host organism host_organism	Homo sapiens

Entity 2 Entity 2 polymer

Description description	Calmodulin-1
Molecular weight formula_weight	16852.5 kDa
Source method src_method	man
Copy count entity_count	4

Polymer Polymer

Polymer type type	polypeptide(L)
Chain IDs strand_id	E,F,G,H

MADQLTEEQIAEFKEAFSLFDKDGDGTITTKELGTVMRSLGQNPTEAELQDMINEVDADGNGTIDFPEFLTMMARKMKDTDSEEEIREAFRVFDKDGNGYISAAELRHVMTNLGEKLTDEEVDEMIREADIDGDGQVNYEEFVQMMTAK

Source Source

Source organism organism	Homo sapiens
Common name common_name	Human
NCBI taxonomy ID ncbi_taxonomy_id	9606
Host organism host_organism	Homo sapiens

Entity 3 Entity 3 non-polymer

Description description	POTASSIUM ION
Molecular weight formula_weight	39.1 kDa
Source method src_method	syn
Copy count entity_count	4

Entity 4 Entity 4 non-polymer

Description description	(2S)-3-(hexadecanoyloxy)-2-[(9Z)-octadec-9-enoyloxy]propyl 2-(trimethylammonio)ethyl phosphate
Molecular weight formula_weight	760.1 kDa
Source method src_method	syn
Copy count entity_count	4

Entity 5 Entity 5 non-polymer

Description description	DODECYL-BETA-D-MALTOSIDE
Molecular weight formula_weight	510.6 kDa
Source method src_method	syn
Copy count entity_count	8

Entity 6 Entity 6 non-polymer

Description description	CALCIUM ION
Molecular weight formula_weight	40.1 kDa
Source method src_method	syn
Copy count entity_count	12

▼

6. Fold Classification (SCOP + CATH) 4 domains

CATH v4.4 (4 domains)

Domain ID domain_id	6cnnE01
Class class	1 — Mainly Alpha
Architecture architecture	10 — Orthogonal Bundle
Topology topology	238 — Recoverin; domain 1
Homologous superfamily homologous superfamily	10 — EF-hand

Domain ID domain_id	6cnnF01
Class class	1 — Mainly Alpha
Architecture architecture	10 — Orthogonal Bundle
Topology topology	238 — Recoverin; domain 1
Homologous superfamily homologous superfamily	10 — EF-hand

Domain ID domain_id	6cnnG01
Class class	1 — Mainly Alpha
Architecture architecture	10 — Orthogonal Bundle
Topology topology	238 — Recoverin; domain 1
Homologous superfamily homologous superfamily	10 — EF-hand

Domain ID domain_id	6cnnH01
Class class	1 — Mainly Alpha
Architecture architecture	10 — Orthogonal Bundle
Topology topology	238 — Recoverin; domain 1
Homologous superfamily homologous superfamily	10 — EF-hand

▶

Unit-cell length a length_a	1.000 Å
Unit-cell length b length_b	1.000 Å
Unit-cell length c length_c	1.000 Å
Unit-cell angle α angle_alpha	90.00 °
Unit-cell angle β angle_beta	90.00 °
Unit-cell angle γ angle_gamma	90.00 °
Molecules per unit cell Z z_pdb	—

Space group space_group	P 1
Space-group number int_tables_number	1
Crystal system crystal_system	—

Resolution resolution	3.500 Å
Low-resolution limit resolution_low	— Å
R factor r_factor	—
R_work r_work	—
R_free r_free	—

Resolution resolution	3.50 Å
Resolution测定Method resolution_method	—
颗粒数 num_particles	91511

Cryo-EM structure of the human SK4/calmodulin channel complex in the Ca2+ bound state I

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

Intermediate conductance calcium-activated potassium channel protein 4

State in the Current Structure

Other States of the Same Protein in the Database

Calmodulin-1

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

6cnn__assembly_1__model_1

6cnn__assembly_1__model_1 | I(q)

6cnn__assembly_1__model_1 | P(r) · Pending

4. Crystallography and Experiment 4. Crystallography & Experiment

Unit cell Unit Cell

Symmetry Symmetry

Refinement Refinement

冷冻电镜 EM 3D

5. Entities and Polymers Entities & Polymers (6)

Entity 1 Entity 1 polymer

Polymer Polymer

Source Source

Entity 2 Entity 2 polymer

Polymer Polymer

Source Source

Entity 3 Entity 3 non-polymer

Entity 4 Entity 4 non-polymer

Entity 5 Entity 5 non-polymer

Entity 6 Entity 6 non-polymer

6. Fold Classification (SCOP + CATH) 4 domains

CATH v4.4 (4 domains)

7. Citations (1)

Cryo-EM structure of the human SK4/calmodulin channel complex in the Ca2+ bound state I

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

Intermediate conductance calcium-activated potassium channel protein 4

State in the Current Structure

Other States of the Same Protein in the Database

Monomer

Homodimer

Homotetramer

Other homooligomers

Heteromeric or nucleic-acid complex

Calmodulin-1

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

6cnn__assembly_1__model_1

6cnn__assembly_1__model_1 | I(q)

6cnn__assembly_1__model_1 | P(r) · Pending

4. Crystallography and Experiment 4. Crystallography & Experiment

Unit cell Unit Cell

Symmetry Symmetry

Refinement Refinement

冷冻电镜 EM 3D

5. Entities and Polymers Entities & Polymers (6)

Entity 1 Entity 1 polymer

Polymer Polymer

Source Source

Entity 2 Entity 2 polymer

Polymer Polymer

Source Source

Entity 3 Entity 3 non-polymer

Entity 4 Entity 4 non-polymer

Entity 5 Entity 5 non-polymer

Entity 6 Entity 6 non-polymer

6. Fold Classification (SCOP + CATH) 4 domains

CATH v4.4 (4 domains)

7. Citations (1)