1tco

TERNARY COMPLEX OF A CALCINEURIN A FRAGMENT, CALCINEURIN B, FKBP12 AND THE IMMUNOSUPPRESSANT DRUG FK506 (TACROLIMUS)

Method: X-RAY DIFFRACTION

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

SERINE/THREONINE PHOSPHATASE B2

Bos taurus

State in the Current Structure

Assembly	Physical composition	Protein state	Molecular copy count	Associated components	Data consistency
1	Protein heterocomplex	Heteromer	Protein 3	SERINE/THREONINE PHOSPHATASE B2 × 1 （P63099） FK506-BINDING PROTEIN × 1 （P62942） ZINC ION × 1 FE (III) ION × 1 PHOSPHATE ION × 1 CALCIUM ION × 4 MYRISTIC ACID × 1 8-DEETHYL-8-[BUT-3-ENYL]-ASCOMYCIN × 1 water × 3	Consistent with protein count

Other States of the Same Protein in the Database

View Construct and Data Evidence

UniProt name	P2BA_BOVIN
Isoform	—
PDB entities	1
Chains and sequence ranges	Author chain A； PDBConstruct 1–375； UniProt 18–392

SERINE/THREONINE PHOSPHATASE B2

Bos taurus

UniProt P63099

State in the Current Structure

Assembly	Physical composition	Protein state	Molecular copy count	Associated components	Data consistency
1	Protein heterocomplex	Heteromer	Protein 3	SERINE/THREONINE PHOSPHATASE B2 × 1 （P48452） FK506-BINDING PROTEIN × 1 （P62942） ZINC ION × 1 FE (III) ION × 1 PHOSPHATE ION × 1 CALCIUM ION × 4 MYRISTIC ACID × 1 8-DEETHYL-8-[BUT-3-ENYL]-ASCOMYCIN × 1 water × 3	Consistent with protein count

Other States of the Same Protein in the Database

View Construct and Data Evidence

UniProt name	CANB1_BOVIN
Isoform	—
PDB entities	2
Chains and sequence ranges	Author chain B； PDBConstruct 1–169； UniProt 1–169

FK506-BINDING PROTEIN

Bos taurus

UniProt P62942

State in the Current Structure

Assembly	Physical composition	Protein state	Molecular copy count	Associated components	Data consistency
1	Protein heterocomplex	Heteromer	Protein 3	SERINE/THREONINE PHOSPHATASE B2 × 1 （P48452） SERINE/THREONINE PHOSPHATASE B2 × 1 （P63099） ZINC ION × 1 FE (III) ION × 1 PHOSPHATE ION × 1 CALCIUM ION × 4 MYRISTIC ACID × 1 8-DEETHYL-8-[BUT-3-ENYL]-ASCOMYCIN × 1 water × 3	Consistent with protein count

Other States of the Same Protein in the Database

View Construct and Data Evidence

UniProt name	FKB1A_HUMAN
Isoform	—
PDB entities	3
Chains and sequence ranges	Author chain C； PDBConstruct 1–107； UniProt 1–107

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	1tco
Deposition date deposition_date	1996-08-21
Structure title title	TERNARY COMPLEX OF A CALCINEURIN A FRAGMENT, CALCINEURIN B, FKBP12 AND THE IMMUNOSUPPRESSANT DRUG FK506 (TACROLIMUS)
Keywords keywords	COMPLEX (HYDROLASE-ISOMERASE), IMMUNOSUPPRESSANT, COMPLEX (HYDROLASE-ISOMERASE) complex; COMPLEX (HYDROLASE/ISOMERASE)
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.

1tco__assembly_1__model_1

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

Download this curve (.dat)

1tco__assembly_1__model_1 | I(q)

100 plotted points; both axes use logarithmic scales.

1tco__assembly_1__model_1 | P(r) · Pending

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

Rg（Guinier）	29.71 Å
Rg (electron density)	29.21 Å
Total Rg	29.82 Å
Atom count	5117
Residues	628
Excluded volume	91647 Å³
Maximum q	0.500 Å⁻¹

Assembly	Model	Structure unit	Oligomeric description	Status	CRYSOL	Actions
1	1	`1tco__assembly_1__model_1`	trimeric （3）	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 (10)

Entity 1 Entity 1 polymer

Description description	SERINE/THREONINE PHOSPHATASE B2
Molecular weight formula_weight	43013.0 kDa
EC 编号 ec_number	3.1.3.16
Source method src_method	man
Copy count entity_count	1

Polymer Polymer

Polymer type type	polypeptide(L)
Chain IDs strand_id	A
Atom count atom_count	5827

VKAVPFPPSHRLTAKEVFDNDGKPRVDILKAHLMKEGRLEETVALRIITEGASILRQEKNLLDIDAPVTVCGDIHGQFFDLMKLFEVGGSPANTRYLFLGDYVDRGYFSIECVLYLWALKILYPKTLFLLRGNHECRHLTEYFTFKQECKIKYSERVYDACMDAFDCLPLAALMNQQFLCVHGGLSPEINTLDDIRKLDRFKEPPAYGPMCDILWSDPLEDFGNEKTQEHFTHNTVRGCSYFYSYPAVCEFLQHNNLLSILRAHEAQDAGYRMYRKSQTTGFPSLITIFSAPNYLDVYNNKAAVLKYENNVMNIRQFNCSPHPYWLPNFMDVFTWSLPFVGEKVTEMLVNVLNICSDDELGSEEDGFDGATAAAR

Source Source

Source organism organism	Bos taurus
Common name common_name	cattle
NCBI taxonomy ID ncbi_taxonomy_id	9913
Host organism host_organism	Escherichia coli

Entity 2 Entity 2 polymer

Description description	SERINE/THREONINE PHOSPHATASE B2
Molecular weight formula_weight	19191.7 kDa
EC 编号 ec_number	3.1.3.16
Source method src_method	man
Copy count entity_count	1

Polymer Polymer

Polymer type type	polypeptide(L)
Chain IDs strand_id	B

GNEASYPLEMCSHFDADEIKRLGKRFKKLDLDNSGSLSVEEFMSLPELQQNPLVQRVIDIFDTDGNGEVDFKEFIEGVSQFSVKGDKEQKLRFAFRIYDMDKDGYISNGELFQVLKMMVGNNLKDTQLQQIVDKTIINADKDGDGRISFEEFCAVVGGLDIHKKMVVDV

Source Source

Source organism organism	Bos taurus
Common name common_name	cattle
NCBI taxonomy ID ncbi_taxonomy_id	9913
Host organism host_organism	Escherichia coli

Entity 3 Entity 3 polymer

Description description	FK506-BINDING PROTEIN
Molecular weight formula_weight	11750.4 kDa
EC 编号 ec_number	5.2.1.8
Source method src_method	man
Copy count entity_count	1

Polymer Polymer

Polymer type type	polypeptide(L)
Chain IDs strand_id	C

GVQVETISPGDGRTFPKAGQTCVVHYTGMLEDGKKFDSSRDRNKPFKFMLGKQEVIRGWEEGVAQMSVGQRAKLTISPDYAYGATGHPGIIPPHATLVFDVELLKLE

Source Source

Source organism organism	Bos taurus
Common name common_name	cattle
NCBI taxonomy ID ncbi_taxonomy_id	9913
Host organism host_organism	Escherichia coli

Entity 4 Entity 4 non-polymer

Description description	ZINC ION
Molecular weight formula_weight	65.4 kDa
Source method src_method	syn
Copy count entity_count	1

Entity 5 Entity 5 non-polymer

Description description	FE (III) ION
Molecular weight formula_weight	55.8 kDa
Source method src_method	syn
Copy count entity_count	1

Entity 6 Entity 6 non-polymer

Description description	PHOSPHATE ION
Molecular weight formula_weight	95.0 kDa
Source method src_method	syn
Copy count entity_count	1

Entity 7 Entity 7 non-polymer

Description description	CALCIUM ION
Molecular weight formula_weight	40.1 kDa
Source method src_method	syn
Copy count entity_count	4

Entity 8 Entity 8 non-polymer

Description description	MYRISTIC ACID
Molecular weight formula_weight	228.4 kDa
Source method src_method	syn
Copy count entity_count	1

Entity 9 Entity 9 non-polymer

Description description	8-DEETHYL-8-[BUT-3-ENYL]-ASCOMYCIN
Molecular weight formula_weight	804.0 kDa
Source method src_method	syn
Copy count entity_count	1

Entity 10 Entity 10 water

Description description	water
Molecular weight formula_weight	18.0 kDa
Source method src_method	nat
Copy count entity_count	710

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6. Fold Classification (SCOP + CATH) 6 domains

SCOP 2.08 (3 domains)

Domain ID domain_id	d1tcoa_
Class class	d — Alpha and beta proteins (a+b)
Fold Fold fold	d.159 — Metallo-dependent phosphatases
Superfamily Superfamily superfamily	d.159.1 — Metallo-dependent phosphatases
Family Family family	d.159.1.3 — Protein serine/threonine phosphatase

Domain ID domain_id	d1tcob_
Class class	a — All alpha proteins
Fold Fold fold	a.39 — EF Hand-like
Superfamily Superfamily superfamily	a.39.1 — EF-hand
Family Family family	a.39.1.5 — Calmodulin-like

Domain ID domain_id	d1tcoc_
Class class	d — Alpha and beta proteins (a+b)
Fold Fold fold	d.26 — FKBP-like
Superfamily Superfamily superfamily	d.26.1 — FKBP-like
Family Family family	d.26.1.1 — FKBP immunophilin/proline isomerase

CATH v4.4 (3 domains)

Domain ID domain_id	1tcoA00
Class class	3 — Alpha Beta
Architecture architecture	60 — 4-Layer Sandwich
Topology topology	21 — Purple Acid Phosphatase; chain A, domain 2
Homologous superfamily homologous superfamily	10 — Metallo-dependent phosphatases

Domain ID domain_id	1tcoB00
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	1tcoC00
Class class	3 — Alpha Beta
Architecture architecture	10 — Roll
Topology topology	50 — Chitinase A; domain 3
Homologous superfamily homologous superfamily	40 —

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Unit-cell length a length_a	90.050 Å
Unit-cell length b length_b	94.430 Å
Unit-cell length c length_c	116.760 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	4

Space group space_group	P 21 21 21
Space-group number int_tables_number	19
Crystal system crystal_system	—

Resolution resolution	2.500 Å
Low-resolution limit resolution_low	7.000 Å
R factor r_factor	0.1950
R_work r_work	0.1950
R_free r_free	0.2820

TERNARY COMPLEX OF A CALCINEURIN A FRAGMENT, CALCINEURIN B, FKBP12 AND THE IMMUNOSUPPRESSANT DRUG FK506 (TACROLIMUS)

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

SERINE/THREONINE PHOSPHATASE B2

State in the Current Structure

Other States of the Same Protein in the Database

Monomer

Homodimer

Homotetramer

Other homooligomers

Heteromeric or nucleic-acid complex

SERINE/THREONINE PHOSPHATASE B2

State in the Current Structure

Other States of the Same Protein in the Database

Monomer

Homodimer

Homotetramer

Other homooligomers

Heteromeric or nucleic-acid complex

FK506-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

1tco__assembly_1__model_1

1tco__assembly_1__model_1 | I(q)

1tco__assembly_1__model_1 | P(r) · Pending

4. Crystallography and Experiment 4. Crystallography & Experiment

Unit cell Unit Cell

Symmetry Symmetry

Refinement Refinement

5. Entities and Polymers Entities & Polymers (10)

Entity 1 Entity 1 polymer

Polymer Polymer

Source Source

Entity 2 Entity 2 polymer

Polymer Polymer

Source Source

Entity 3 Entity 3 polymer

Polymer Polymer

Source Source

Entity 4 Entity 4 non-polymer

Entity 5 Entity 5 non-polymer

Entity 6 Entity 6 non-polymer

Entity 7 Entity 7 non-polymer

Entity 8 Entity 8 non-polymer

Entity 9 Entity 9 non-polymer

Entity 10 Entity 10 water

6. Fold Classification (SCOP + CATH) 6 domains

SCOP 2.08 (3 domains)

CATH v4.4 (3 domains)

7. Citations (1)