1sej

Crystal Structure of Dihydrofolate Reductase-Thymidylate Synthase from Cryptosporidium hominis Bound to 1843U89/NADPH/dUMP

Method: X-RAY DIFFRACTION

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

bifunctional dihydrofolate reductase-thymidylate synthase

Cryptosporidium hominis

State in the Current Structure

Assembly	Physical composition	Protein state	Molecular copy count	Associated components	Data consistency
1	Protein homooligomer	Homooligomer	Protein 2	;2'-DEOXYURIDINE 5'-MONOPHOSPHATE ; × 2 S)-2-(5(((1,2-DIHYDRO-3-METHYL-1-OXOBENZO(F)QUINAZOLIN-9-YL)METHYL)AMINO)1-OXO-2-ISOINDOLINYL)GLUTARIC ACID × 4 NADPH DIHYDRO-NICOTINAMIDE-ADENINE-DINUCLEOTIDE PHOSPHATE × 2 water × 2	Consistent with protein count
2	Protein homooligomer	Homooligomer	Protein 2	;2'-DEOXYURIDINE 5'-MONOPHOSPHATE ; × 2 S)-2-(5(((1,2-DIHYDRO-3-METHYL-1-OXOBENZO(F)QUINAZOLIN-9-YL)METHYL)AMINO)1-OXO-2-ISOINDOLINYL)GLUTARIC ACID × 4 NADPH DIHYDRO-NICOTINAMIDE-ADENINE-DINUCLEOTIDE PHOSPHATE × 2 water × 2	Consistent with protein count
3	Protein homooligomer	Homooligomer	Protein 2	;2'-DEOXYURIDINE 5'-MONOPHOSPHATE ; × 2 S)-2-(5(((1,2-DIHYDRO-3-METHYL-1-OXOBENZO(F)QUINAZOLIN-9-YL)METHYL)AMINO)1-OXO-2-ISOINDOLINYL)GLUTARIC ACID × 4 NADPH DIHYDRO-NICOTINAMIDE-ADENINE-DINUCLEOTIDE PHOSPHATE × 2 water × 2	Consistent with protein count

Other States of the Same Protein in the Database

View Construct and Data Evidence

UniProt name	Q27552_CRYPV
Isoform	—
PDB entities	1
Chains and sequence ranges	Author chain A； PDBConstruct 1–521； UniProt 1–521 Author chain B； PDBConstruct 1–521； UniProt 1–521 Author chain C； PDBConstruct 1–521； UniProt 1–521 Author chain D； PDBConstruct 1–521； UniProt 1–521 Author chain E； PDBConstruct 1–521； UniProt 1–521

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	1sej
Deposition date deposition_date	2004-02-17
Structure title title	Crystal Structure of Dihydrofolate Reductase-Thymidylate Synthase from Cryptosporidium hominis Bound to 1843U89/NADPH/dUMP
Keywords keywords	bifunctional enzyme, TRANSFERASE, OXIDOREDUCTASE; TRANSFERASE, OXIDOREDUCTASE
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.

1sej__assembly_3__model_1

Assembly 3 · Model 1 · CRYSOL 4.1.3-1-20251215 (887e7ef)

Download this curve (.dat)

1sej__assembly_3__model_1 | I(q)

100 plotted points; both axes use logarithmic scales.

1sej__assembly_3__model_1 | P(r) · Pending

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

Rg（Guinier）	33.32 Å
Rg (electron density)	32.30 Å
Total Rg	32.87 Å
Atom count	8730
Residues	1038
Excluded volume	155000 Å³
Maximum q	0.500 Å⁻¹

Assembly	Model	Structure unit	Oligomeric description	Status	CRYSOL	Actions
1	1	`1sej__assembly_1__model_1`	dimeric （2）	Success	4.1.3-1-20251215 (887e7ef)	View Download
2	1	`1sej__assembly_2__model_1`	dimeric （2）	Success	4.1.3-1-20251215 (887e7ef)	View Download
3	1	`1sej__assembly_3__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 (5)

Entity 1 Entity 1 polymer

Description description	bifunctional dihydrofolate reductase-thymidylate synthase
Molecular weight formula_weight	60262.5 kDa
EC 编号 ec_number	2.1.1.45, 1.5.1.3
Source method src_method	man
Copy count entity_count	5

Polymer Polymer

Polymer type type	polypeptide(L)
Chain IDs strand_id	A,B,C,D,E
Atom count atom_count	22194

MSEKNVSIVVAASVLSSGIGINGQLPWSISEDLKFFSKITNNKCDSNKKNALIMGRKTWDSIGRRPLKNRIIVVISSSLPQDEADPNVVVFRNLEDSIENLMNDDSIENIFVCGGESIYRDALKDNFVDRIYLTRVALEDIEFDTYFPEIPETFLPVYMSQTFCTKNISYDFMIFEKQEKKTLQNCDPARGQLKSIDDTVDLLGEIFGIRKMGNRHKFPKEEIYNTPSIRFGREHYEFQYLDLLSRVLENGAYRENRTGISTYSIFGQMMRFDMRESFPLLTTKKVAIRSIFEELIWFIKGDTNGNHLIEKKVYIWSGNGSKEYLERIGLGHREENDLGPIYGFQWRHYNGEYKTMHDDYTGVGVDQLAKLIETLKNNPKDRRHILTAWNPSALSQMALPPCHVLSQYYVTNDNCLSCNLYQRSCDLGLGSPFNIASYAILTMMLAQVCGYEPGELAIFIGDAHIYENHLTQLKEQLSRTPRPFPQLKFKRKVENIEDFKWEDIELIGYYPYPTIKMDMAV

Source Source

Source organism organism	Cryptosporidium hominis
NCBI taxonomy ID ncbi_taxonomy_id	237895
Host organism host_organism	Escherichia coli

Entity 2 Entity 2 non-polymer

Description description	;2'-DEOXYURIDINE 5'-MONOPHOSPHATE ;
Molecular weight formula_weight	308.2 kDa
Source method src_method	syn
Copy count entity_count	5

Entity 3 Entity 3 non-polymer

Description description	S)-2-(5(((1,2-DIHYDRO-3-METHYL-1-OXOBENZO(F)QUINAZOLIN-9-YL)METHYL)AMINO)1-OXO-2-ISOINDOLINYL)GLUTARIC ACID
Molecular weight formula_weight	500.5 kDa
Source method src_method	syn
Copy count entity_count	10

Entity 4 Entity 4 non-polymer

Description description	NADPH DIHYDRO-NICOTINAMIDE-ADENINE-DINUCLEOTIDE PHOSPHATE
Molecular weight formula_weight	745.4 kDa
Source method src_method	syn
Copy count entity_count	5

Entity 5 Entity 5 water

Description description	water
Molecular weight formula_weight	18.0 kDa
Source method src_method	nat
Copy count entity_count	369

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6. Fold Classification (SCOP + CATH) 25 domains

SCOP 2.08 (10 domains)

Domain ID domain_id	d1seja1
Class class	c — Alpha and beta proteins (a/b)
Fold Fold fold	c.71 — Dihydrofolate reductase-like
Superfamily Superfamily superfamily	c.71.1 — Dihydrofolate reductase-like
Family Family family	c.71.1.1 — Dihydrofolate reductases

Domain ID domain_id	d1seja2
Class class	d — Alpha and beta proteins (a+b)
Fold Fold fold	d.117 — Thymidylate synthase/dCMP hydroxymethylase
Superfamily Superfamily superfamily	d.117.1 — Thymidylate synthase/dCMP hydroxymethylase
Family Family family	d.117.1.1 — Thymidylate synthase/dCMP hydroxymethylase

Domain ID domain_id	d1sejb1
Class class	c — Alpha and beta proteins (a/b)
Fold Fold fold	c.71 — Dihydrofolate reductase-like
Superfamily Superfamily superfamily	c.71.1 — Dihydrofolate reductase-like
Family Family family	c.71.1.1 — Dihydrofolate reductases

Domain ID domain_id	d1sejb2
Class class	d — Alpha and beta proteins (a+b)
Fold Fold fold	d.117 — Thymidylate synthase/dCMP hydroxymethylase
Superfamily Superfamily superfamily	d.117.1 — Thymidylate synthase/dCMP hydroxymethylase
Family Family family	d.117.1.1 — Thymidylate synthase/dCMP hydroxymethylase

Domain ID domain_id	d1sejc1
Class class	c — Alpha and beta proteins (a/b)
Fold Fold fold	c.71 — Dihydrofolate reductase-like
Superfamily Superfamily superfamily	c.71.1 — Dihydrofolate reductase-like
Family Family family	c.71.1.1 — Dihydrofolate reductases

Domain ID domain_id	d1sejc2
Class class	d — Alpha and beta proteins (a+b)
Fold Fold fold	d.117 — Thymidylate synthase/dCMP hydroxymethylase
Superfamily Superfamily superfamily	d.117.1 — Thymidylate synthase/dCMP hydroxymethylase
Family Family family	d.117.1.1 — Thymidylate synthase/dCMP hydroxymethylase

Domain ID domain_id	d1sejd1
Class class	c — Alpha and beta proteins (a/b)
Fold Fold fold	c.71 — Dihydrofolate reductase-like
Superfamily Superfamily superfamily	c.71.1 — Dihydrofolate reductase-like
Family Family family	c.71.1.1 — Dihydrofolate reductases

Domain ID domain_id	d1sejd2
Class class	d — Alpha and beta proteins (a+b)
Fold Fold fold	d.117 — Thymidylate synthase/dCMP hydroxymethylase
Superfamily Superfamily superfamily	d.117.1 — Thymidylate synthase/dCMP hydroxymethylase
Family Family family	d.117.1.1 — Thymidylate synthase/dCMP hydroxymethylase

Domain ID domain_id	d1seje1
Class class	c — Alpha and beta proteins (a/b)
Fold Fold fold	c.71 — Dihydrofolate reductase-like
Superfamily Superfamily superfamily	c.71.1 — Dihydrofolate reductase-like
Family Family family	c.71.1.1 — Dihydrofolate reductases

Domain ID domain_id	d1seje2
Class class	d — Alpha and beta proteins (a+b)
Fold Fold fold	d.117 — Thymidylate synthase/dCMP hydroxymethylase
Superfamily Superfamily superfamily	d.117.1 — Thymidylate synthase/dCMP hydroxymethylase
Family Family family	d.117.1.1 — Thymidylate synthase/dCMP hydroxymethylase

CATH v4.4 (15 domains)

Domain ID domain_id	1sejA01
Class class	3 — Alpha Beta
Architecture architecture	40 — 3-Layer(aba) Sandwich
Topology topology	430 — Dihydrofolate Reductase, subunit A
Homologous superfamily homologous superfamily	10 — Dihydrofolate Reductase, subunit A

Domain ID domain_id	1sejA02
Class class	3 — Alpha Beta
Architecture architecture	30 — 2-Layer Sandwich
Topology topology	572 — Thymidylate Synthase; Chain A
Homologous superfamily homologous superfamily	10 — Thymidylate synthase/dCMP hydroxymethylase domain

Domain ID domain_id	1sejA03
Class class	3 — Alpha Beta
Architecture architecture	30 — 2-Layer Sandwich
Topology topology	572 — Thymidylate Synthase; Chain A
Homologous superfamily homologous superfamily	10 — Thymidylate synthase/dCMP hydroxymethylase domain

Domain ID domain_id	1sejB01
Class class	3 — Alpha Beta
Architecture architecture	40 — 3-Layer(aba) Sandwich
Topology topology	430 — Dihydrofolate Reductase, subunit A
Homologous superfamily homologous superfamily	10 — Dihydrofolate Reductase, subunit A

Domain ID domain_id	1sejB02
Class class	3 — Alpha Beta
Architecture architecture	30 — 2-Layer Sandwich
Topology topology	572 — Thymidylate Synthase; Chain A
Homologous superfamily homologous superfamily	10 — Thymidylate synthase/dCMP hydroxymethylase domain

Domain ID domain_id	1sejB03
Class class	3 — Alpha Beta
Architecture architecture	30 — 2-Layer Sandwich
Topology topology	572 — Thymidylate Synthase; Chain A
Homologous superfamily homologous superfamily	10 — Thymidylate synthase/dCMP hydroxymethylase domain

Domain ID domain_id	1sejC01
Class class	3 — Alpha Beta
Architecture architecture	40 — 3-Layer(aba) Sandwich
Topology topology	430 — Dihydrofolate Reductase, subunit A
Homologous superfamily homologous superfamily	10 — Dihydrofolate Reductase, subunit A

Domain ID domain_id	1sejC02
Class class	3 — Alpha Beta
Architecture architecture	30 — 2-Layer Sandwich
Topology topology	572 — Thymidylate Synthase; Chain A
Homologous superfamily homologous superfamily	10 — Thymidylate synthase/dCMP hydroxymethylase domain

Domain ID domain_id	1sejC03
Class class	3 — Alpha Beta
Architecture architecture	30 — 2-Layer Sandwich
Topology topology	572 — Thymidylate Synthase; Chain A
Homologous superfamily homologous superfamily	10 — Thymidylate synthase/dCMP hydroxymethylase domain

Domain ID domain_id	1sejD01
Class class	3 — Alpha Beta
Architecture architecture	40 — 3-Layer(aba) Sandwich
Topology topology	430 — Dihydrofolate Reductase, subunit A
Homologous superfamily homologous superfamily	10 — Dihydrofolate Reductase, subunit A

Domain ID domain_id	1sejD02
Class class	3 — Alpha Beta
Architecture architecture	30 — 2-Layer Sandwich
Topology topology	572 — Thymidylate Synthase; Chain A
Homologous superfamily homologous superfamily	10 — Thymidylate synthase/dCMP hydroxymethylase domain

Domain ID domain_id	1sejD03
Class class	3 — Alpha Beta
Architecture architecture	30 — 2-Layer Sandwich
Topology topology	572 — Thymidylate Synthase; Chain A
Homologous superfamily homologous superfamily	10 — Thymidylate synthase/dCMP hydroxymethylase domain

Domain ID domain_id	1sejE01
Class class	3 — Alpha Beta
Architecture architecture	40 — 3-Layer(aba) Sandwich
Topology topology	430 — Dihydrofolate Reductase, subunit A
Homologous superfamily homologous superfamily	10 — Dihydrofolate Reductase, subunit A

Domain ID domain_id	1sejE02
Class class	3 — Alpha Beta
Architecture architecture	30 — 2-Layer Sandwich
Topology topology	572 — Thymidylate Synthase; Chain A
Homologous superfamily homologous superfamily	10 — Thymidylate synthase/dCMP hydroxymethylase domain

Domain ID domain_id	1sejE03
Class class	3 — Alpha Beta
Architecture architecture	30 — 2-Layer Sandwich
Topology topology	572 — Thymidylate Synthase; Chain A
Homologous superfamily homologous superfamily	10 — Thymidylate synthase/dCMP hydroxymethylase domain

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Unit-cell length a length_a	214.900 Å
Unit-cell length b length_b	116.300 Å
Unit-cell length c length_c	219.700 Å
Unit-cell angle α angle_alpha	90.00 °
Unit-cell angle β angle_beta	95.23 °
Unit-cell angle γ angle_gamma	90.00 °
Molecules per unit cell Z z_pdb	20

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

Resolution resolution	2.870 Å
Low-resolution limit resolution_low	45.150 Å
R factor r_factor	0.2200
R_work r_work	0.2200
R_free r_free	0.2370

Crystal Structure of Dihydrofolate Reductase-Thymidylate Synthase from Cryptosporidium hominis Bound to 1843U89/NADPH/dUMP

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

bifunctional dihydrofolate reductase-thymidylate synthase

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

1sej__assembly_3__model_1

1sej__assembly_3__model_1 | I(q)

1sej__assembly_3__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 (5)

Entity 1 Entity 1 polymer

Polymer Polymer

Source Source

Entity 2 Entity 2 non-polymer

Entity 3 Entity 3 non-polymer

Entity 4 Entity 4 non-polymer

Entity 5 Entity 5 water

6. Fold Classification (SCOP + CATH) 25 domains

SCOP 2.08 (10 domains)

CATH v4.4 (15 domains)

7. Citations (1)

Crystal Structure of Dihydrofolate Reductase-Thymidylate Synthase from Cryptosporidium hominis Bound to 1843U89/NADPH/dUMP

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

bifunctional dihydrofolate reductase-thymidylate synthase

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

1sej__assembly_3__model_1

1sej__assembly_3__model_1 | I(q)

1sej__assembly_3__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 (5)

Entity 1 Entity 1 polymer

Polymer Polymer

Source Source

Entity 2 Entity 2 non-polymer

Entity 3 Entity 3 non-polymer

Entity 4 Entity 4 non-polymer

Entity 5 Entity 5 water

6. Fold Classification (SCOP + CATH) 25 domains

SCOP 2.08 (10 domains)

CATH v4.4 (15 domains)

7. Citations (1)