1gtp

GTP CYCLOHYDROLASE I

Method: X-RAY DIFFRACTION

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

GTP CYCLOHYDROLASE I

Escherichia coli

State in the Current Structure

Assembly	Physical composition	Protein state	Molecular copy count	Associated components	Data consistency
1	Protein homooligomer	Homooligomer	Protein 10	SULFATE ION × 10 water × 10	Consistent with protein count
2	Protein homooligomer	Homooligomer	Protein 10	SULFATE ION × 10 water × 10	Consistent with protein count
3	Protein homooligomer	Homooligomer	Protein 20	SULFATE ION × 20 water × 20	Consistent with protein count

Other States of the Same Protein in the Database

View Construct and Data Evidence

UniProt name	GCH1_ECOLI
Isoform	—
PDB entities	1
Chains and sequence ranges	Author chain A； PDBConstruct 1–221； UniProt 1–221 Author chain B； PDBConstruct 1–221； UniProt 1–221 Author chain C； PDBConstruct 1–221； UniProt 1–221 Author chain D； PDBConstruct 1–221； UniProt 1–221 Author chain E； PDBConstruct 1–221； UniProt 1–221 Author chain F； PDBConstruct 1–221； UniProt 1–221 Author chain G； PDBConstruct 1–221； UniProt 1–221 Author chain H； PDBConstruct 1–221； UniProt 1–221 Author chain I； PDBConstruct 1–221； UniProt 1–221 Author chain J； PDBConstruct 1–221； UniProt 1–221 Author chain K； PDBConstruct 1–221； UniProt 1–221 Author chain L； PDBConstruct 1–221； UniProt 1–221 Author chain M； PDBConstruct 1–221； UniProt 1–221 Author chain N； PDBConstruct 1–221； UniProt 1–221 Author chain O； PDBConstruct 1–221； UniProt 1–221 Author chain P； PDBConstruct 1–221； UniProt 1–221 Author chain Q； PDBConstruct 1–221； UniProt 1–221 Author chain R； PDBConstruct 1–221； UniProt 1–221 Author chain S； PDBConstruct 1–221； UniProt 1–221 Author chain T； PDBConstruct 1–221； UniProt 1–221

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	1gtp
Deposition date deposition_date	1995-09-16
Structure title title	GTP CYCLOHYDROLASE I
Keywords keywords	GTP, PURINE HYDROLYSIS, PTERINE SYNTHESIS, HYDROLASE; HYDROLASE
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.

1gtp__assembly_1__model_1

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

Download this curve (.dat)

1gtp__assembly_1__model_1 | I(q)

100 plotted points; both axes use logarithmic scales.

1gtp__assembly_1__model_1 | P(r) · Pending

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

Rg（Guinier）	38.03 Å
Rg (electron density)	37.23 Å
Total Rg	37.80 Å
Atom count	21410
Residues	2210
Excluded volume	309950 Å³
Maximum q	0.500 Å⁻¹

Assembly	Model	Structure unit	Oligomeric description	Status	CRYSOL	Actions
1	1	`1gtp__assembly_1__model_1`	decameric （10）	Success	4.1.3-1-20251215 (887e7ef)	View Download
2	1	`1gtp__assembly_2__model_1`	decameric （10）	Success	4.1.3-1-20251215 (887e7ef)	View Download
3	1	`1gtp__assembly_3__model_1`	eicosameric （20）	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 (3)

Entity 1 Entity 1 polymer

Description description	GTP CYCLOHYDROLASE I
Molecular weight formula_weight	24733.5 kDa
EC 编号 ec_number	3.5.4.16
Source method src_method	man
Copy count entity_count	20

Polymer Polymer

Polymer type type	polypeptide(L)
Chain IDs strand_id	A,B,C,D,E,F,G,H,I,J,K,L,M,N,O,P,Q,R,S,T
Atom count atom_count	43780

PSLSKEAALVHEALVARGLETPLRPPVHEMDNETRKSLIAGHMTEIMQLLNLDLADDSLMETPHRIAKMYVDEIFSGLDYANFPKITLIENKMKVDEMVTVRDITLTSTCEHHFVTIDGKATVAYIPKDSVIGLSKINRIVQFFAQRPQVQERLTQQILIALQTLLGTNNVAVSIDAVHYCVKARGIRDATSATTTTSLGGLFKSSQNTRHEFLRAVRHHN

Source Source

Source organism organism	Escherichia coli
NCBI taxonomy ID ncbi_taxonomy_id	562
Host organism host_organism	Escherichia coli

Entity 2 Entity 2 non-polymer

Description description	SULFATE ION
Molecular weight formula_weight	96.1 kDa
Source method src_method	syn
Copy count entity_count	20

Entity 3 Entity 3 water

Description description	water
Molecular weight formula_weight	18.0 kDa
Source method src_method	nat
Copy count entity_count	320

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6. Fold Classification (SCOP + CATH) 60 domains

SCOP 2.08 (20 domains)

Domain ID domain_id	d1gtpa_
Class class	d — Alpha and beta proteins (a+b)
Fold Fold fold	d.96 — T-fold
Superfamily Superfamily superfamily	d.96.1 — Tetrahydrobiopterin biosynthesis enzymes-like
Family Family family	d.96.1.1 — GTP cyclohydrolase I

Domain ID domain_id	d1gtpb_
Class class	d — Alpha and beta proteins (a+b)
Fold Fold fold	d.96 — T-fold
Superfamily Superfamily superfamily	d.96.1 — Tetrahydrobiopterin biosynthesis enzymes-like
Family Family family	d.96.1.1 — GTP cyclohydrolase I

Domain ID domain_id	d1gtpc_
Class class	d — Alpha and beta proteins (a+b)
Fold Fold fold	d.96 — T-fold
Superfamily Superfamily superfamily	d.96.1 — Tetrahydrobiopterin biosynthesis enzymes-like
Family Family family	d.96.1.1 — GTP cyclohydrolase I

Domain ID domain_id	d1gtpd_
Class class	d — Alpha and beta proteins (a+b)
Fold Fold fold	d.96 — T-fold
Superfamily Superfamily superfamily	d.96.1 — Tetrahydrobiopterin biosynthesis enzymes-like
Family Family family	d.96.1.1 — GTP cyclohydrolase I

Domain ID domain_id	d1gtpe_
Class class	d — Alpha and beta proteins (a+b)
Fold Fold fold	d.96 — T-fold
Superfamily Superfamily superfamily	d.96.1 — Tetrahydrobiopterin biosynthesis enzymes-like
Family Family family	d.96.1.1 — GTP cyclohydrolase I

Domain ID domain_id	d1gtpf_
Class class	d — Alpha and beta proteins (a+b)
Fold Fold fold	d.96 — T-fold
Superfamily Superfamily superfamily	d.96.1 — Tetrahydrobiopterin biosynthesis enzymes-like
Family Family family	d.96.1.1 — GTP cyclohydrolase I

Domain ID domain_id	d1gtpg_
Class class	d — Alpha and beta proteins (a+b)
Fold Fold fold	d.96 — T-fold
Superfamily Superfamily superfamily	d.96.1 — Tetrahydrobiopterin biosynthesis enzymes-like
Family Family family	d.96.1.1 — GTP cyclohydrolase I

Domain ID domain_id	d1gtph_
Class class	d — Alpha and beta proteins (a+b)
Fold Fold fold	d.96 — T-fold
Superfamily Superfamily superfamily	d.96.1 — Tetrahydrobiopterin biosynthesis enzymes-like
Family Family family	d.96.1.1 — GTP cyclohydrolase I

Domain ID domain_id	d1gtpi_
Class class	d — Alpha and beta proteins (a+b)
Fold Fold fold	d.96 — T-fold
Superfamily Superfamily superfamily	d.96.1 — Tetrahydrobiopterin biosynthesis enzymes-like
Family Family family	d.96.1.1 — GTP cyclohydrolase I

Domain ID domain_id	d1gtpj_
Class class	d — Alpha and beta proteins (a+b)
Fold Fold fold	d.96 — T-fold
Superfamily Superfamily superfamily	d.96.1 — Tetrahydrobiopterin biosynthesis enzymes-like
Family Family family	d.96.1.1 — GTP cyclohydrolase I

Domain ID domain_id	d1gtpk_
Class class	d — Alpha and beta proteins (a+b)
Fold Fold fold	d.96 — T-fold
Superfamily Superfamily superfamily	d.96.1 — Tetrahydrobiopterin biosynthesis enzymes-like
Family Family family	d.96.1.1 — GTP cyclohydrolase I

Domain ID domain_id	d1gtpl_
Class class	d — Alpha and beta proteins (a+b)
Fold Fold fold	d.96 — T-fold
Superfamily Superfamily superfamily	d.96.1 — Tetrahydrobiopterin biosynthesis enzymes-like
Family Family family	d.96.1.1 — GTP cyclohydrolase I

Domain ID domain_id	d1gtpm_
Class class	d — Alpha and beta proteins (a+b)
Fold Fold fold	d.96 — T-fold
Superfamily Superfamily superfamily	d.96.1 — Tetrahydrobiopterin biosynthesis enzymes-like
Family Family family	d.96.1.1 — GTP cyclohydrolase I

Domain ID domain_id	d1gtpn_
Class class	d — Alpha and beta proteins (a+b)
Fold Fold fold	d.96 — T-fold
Superfamily Superfamily superfamily	d.96.1 — Tetrahydrobiopterin biosynthesis enzymes-like
Family Family family	d.96.1.1 — GTP cyclohydrolase I

Domain ID domain_id	d1gtpo_
Class class	d — Alpha and beta proteins (a+b)
Fold Fold fold	d.96 — T-fold
Superfamily Superfamily superfamily	d.96.1 — Tetrahydrobiopterin biosynthesis enzymes-like
Family Family family	d.96.1.1 — GTP cyclohydrolase I

Domain ID domain_id	d1gtpp_
Class class	d — Alpha and beta proteins (a+b)
Fold Fold fold	d.96 — T-fold
Superfamily Superfamily superfamily	d.96.1 — Tetrahydrobiopterin biosynthesis enzymes-like
Family Family family	d.96.1.1 — GTP cyclohydrolase I

Domain ID domain_id	d1gtpq_
Class class	d — Alpha and beta proteins (a+b)
Fold Fold fold	d.96 — T-fold
Superfamily Superfamily superfamily	d.96.1 — Tetrahydrobiopterin biosynthesis enzymes-like
Family Family family	d.96.1.1 — GTP cyclohydrolase I

Domain ID domain_id	d1gtpr_
Class class	d — Alpha and beta proteins (a+b)
Fold Fold fold	d.96 — T-fold
Superfamily Superfamily superfamily	d.96.1 — Tetrahydrobiopterin biosynthesis enzymes-like
Family Family family	d.96.1.1 — GTP cyclohydrolase I

Domain ID domain_id	d1gtps_
Class class	d — Alpha and beta proteins (a+b)
Fold Fold fold	d.96 — T-fold
Superfamily Superfamily superfamily	d.96.1 — Tetrahydrobiopterin biosynthesis enzymes-like
Family Family family	d.96.1.1 — GTP cyclohydrolase I

Domain ID domain_id	d1gtpt_
Class class	d — Alpha and beta proteins (a+b)
Fold Fold fold	d.96 — T-fold
Superfamily Superfamily superfamily	d.96.1 — Tetrahydrobiopterin biosynthesis enzymes-like
Family Family family	d.96.1.1 — GTP cyclohydrolase I

CATH v4.4 (40 domains)

Domain ID domain_id	1gtpA01
Class class	1 — Mainly Alpha
Architecture architecture	10 — Orthogonal Bundle
Topology topology	286 — GTP Cyclohydrolase I; Chain A, domain 1
Homologous superfamily homologous superfamily	10 — GTP cyclohydrolase I, N-terminal domain

Domain ID domain_id	1gtpA02
Class class	3 — Alpha Beta
Architecture architecture	30 — 2-Layer Sandwich
Topology topology	1130 — GTP Cyclohydrolase I, domain 2
Homologous superfamily homologous superfamily	10 — GTP cyclohydrolase I, C-terminal domain/NADPH-dependent 7-cyano-7-deazaguanine reductase, N-terminal domain

Domain ID domain_id	1gtpB01
Class class	1 — Mainly Alpha
Architecture architecture	10 — Orthogonal Bundle
Topology topology	286 — GTP Cyclohydrolase I; Chain A, domain 1
Homologous superfamily homologous superfamily	10 — GTP cyclohydrolase I, N-terminal domain

Domain ID domain_id	1gtpB02
Class class	3 — Alpha Beta
Architecture architecture	30 — 2-Layer Sandwich
Topology topology	1130 — GTP Cyclohydrolase I, domain 2
Homologous superfamily homologous superfamily	10 — GTP cyclohydrolase I, C-terminal domain/NADPH-dependent 7-cyano-7-deazaguanine reductase, N-terminal domain

Domain ID domain_id	1gtpC01
Class class	1 — Mainly Alpha
Architecture architecture	10 — Orthogonal Bundle
Topology topology	286 — GTP Cyclohydrolase I; Chain A, domain 1
Homologous superfamily homologous superfamily	10 — GTP cyclohydrolase I, N-terminal domain

Domain ID domain_id	1gtpC02
Class class	3 — Alpha Beta
Architecture architecture	30 — 2-Layer Sandwich
Topology topology	1130 — GTP Cyclohydrolase I, domain 2
Homologous superfamily homologous superfamily	10 — GTP cyclohydrolase I, C-terminal domain/NADPH-dependent 7-cyano-7-deazaguanine reductase, N-terminal domain

Domain ID domain_id	1gtpD01
Class class	1 — Mainly Alpha
Architecture architecture	10 — Orthogonal Bundle
Topology topology	286 — GTP Cyclohydrolase I; Chain A, domain 1
Homologous superfamily homologous superfamily	10 — GTP cyclohydrolase I, N-terminal domain

Domain ID domain_id	1gtpD02
Class class	3 — Alpha Beta
Architecture architecture	30 — 2-Layer Sandwich
Topology topology	1130 — GTP Cyclohydrolase I, domain 2
Homologous superfamily homologous superfamily	10 — GTP cyclohydrolase I, C-terminal domain/NADPH-dependent 7-cyano-7-deazaguanine reductase, N-terminal domain

Domain ID domain_id	1gtpE01
Class class	1 — Mainly Alpha
Architecture architecture	10 — Orthogonal Bundle
Topology topology	286 — GTP Cyclohydrolase I; Chain A, domain 1
Homologous superfamily homologous superfamily	10 — GTP cyclohydrolase I, N-terminal domain

Domain ID domain_id	1gtpE02
Class class	3 — Alpha Beta
Architecture architecture	30 — 2-Layer Sandwich
Topology topology	1130 — GTP Cyclohydrolase I, domain 2
Homologous superfamily homologous superfamily	10 — GTP cyclohydrolase I, C-terminal domain/NADPH-dependent 7-cyano-7-deazaguanine reductase, N-terminal domain

Domain ID domain_id	1gtpF01
Class class	1 — Mainly Alpha
Architecture architecture	10 — Orthogonal Bundle
Topology topology	286 — GTP Cyclohydrolase I; Chain A, domain 1
Homologous superfamily homologous superfamily	10 — GTP cyclohydrolase I, N-terminal domain

Domain ID domain_id	1gtpF02
Class class	3 — Alpha Beta
Architecture architecture	30 — 2-Layer Sandwich
Topology topology	1130 — GTP Cyclohydrolase I, domain 2
Homologous superfamily homologous superfamily	10 — GTP cyclohydrolase I, C-terminal domain/NADPH-dependent 7-cyano-7-deazaguanine reductase, N-terminal domain

Domain ID domain_id	1gtpG01
Class class	1 — Mainly Alpha
Architecture architecture	10 — Orthogonal Bundle
Topology topology	286 — GTP Cyclohydrolase I; Chain A, domain 1
Homologous superfamily homologous superfamily	10 — GTP cyclohydrolase I, N-terminal domain

Domain ID domain_id	1gtpG02
Class class	3 — Alpha Beta
Architecture architecture	30 — 2-Layer Sandwich
Topology topology	1130 — GTP Cyclohydrolase I, domain 2
Homologous superfamily homologous superfamily	10 — GTP cyclohydrolase I, C-terminal domain/NADPH-dependent 7-cyano-7-deazaguanine reductase, N-terminal domain

Domain ID domain_id	1gtpH01
Class class	1 — Mainly Alpha
Architecture architecture	10 — Orthogonal Bundle
Topology topology	286 — GTP Cyclohydrolase I; Chain A, domain 1
Homologous superfamily homologous superfamily	10 — GTP cyclohydrolase I, N-terminal domain

Domain ID domain_id	1gtpH02
Class class	3 — Alpha Beta
Architecture architecture	30 — 2-Layer Sandwich
Topology topology	1130 — GTP Cyclohydrolase I, domain 2
Homologous superfamily homologous superfamily	10 — GTP cyclohydrolase I, C-terminal domain/NADPH-dependent 7-cyano-7-deazaguanine reductase, N-terminal domain

Domain ID domain_id	1gtpI01
Class class	1 — Mainly Alpha
Architecture architecture	10 — Orthogonal Bundle
Topology topology	286 — GTP Cyclohydrolase I; Chain A, domain 1
Homologous superfamily homologous superfamily	10 — GTP cyclohydrolase I, N-terminal domain

Domain ID domain_id	1gtpI02
Class class	3 — Alpha Beta
Architecture architecture	30 — 2-Layer Sandwich
Topology topology	1130 — GTP Cyclohydrolase I, domain 2
Homologous superfamily homologous superfamily	10 — GTP cyclohydrolase I, C-terminal domain/NADPH-dependent 7-cyano-7-deazaguanine reductase, N-terminal domain

Domain ID domain_id	1gtpJ01
Class class	1 — Mainly Alpha
Architecture architecture	10 — Orthogonal Bundle
Topology topology	286 — GTP Cyclohydrolase I; Chain A, domain 1
Homologous superfamily homologous superfamily	10 — GTP cyclohydrolase I, N-terminal domain

Domain ID domain_id	1gtpJ02
Class class	3 — Alpha Beta
Architecture architecture	30 — 2-Layer Sandwich
Topology topology	1130 — GTP Cyclohydrolase I, domain 2
Homologous superfamily homologous superfamily	10 — GTP cyclohydrolase I, C-terminal domain/NADPH-dependent 7-cyano-7-deazaguanine reductase, N-terminal domain

Domain ID domain_id	1gtpK01
Class class	1 — Mainly Alpha
Architecture architecture	10 — Orthogonal Bundle
Topology topology	286 — GTP Cyclohydrolase I; Chain A, domain 1
Homologous superfamily homologous superfamily	10 — GTP cyclohydrolase I, N-terminal domain

Domain ID domain_id	1gtpK02
Class class	3 — Alpha Beta
Architecture architecture	30 — 2-Layer Sandwich
Topology topology	1130 — GTP Cyclohydrolase I, domain 2
Homologous superfamily homologous superfamily	10 — GTP cyclohydrolase I, C-terminal domain/NADPH-dependent 7-cyano-7-deazaguanine reductase, N-terminal domain

Domain ID domain_id	1gtpL01
Class class	1 — Mainly Alpha
Architecture architecture	10 — Orthogonal Bundle
Topology topology	286 — GTP Cyclohydrolase I; Chain A, domain 1
Homologous superfamily homologous superfamily	10 — GTP cyclohydrolase I, N-terminal domain

Domain ID domain_id	1gtpL02
Class class	3 — Alpha Beta
Architecture architecture	30 — 2-Layer Sandwich
Topology topology	1130 — GTP Cyclohydrolase I, domain 2
Homologous superfamily homologous superfamily	10 — GTP cyclohydrolase I, C-terminal domain/NADPH-dependent 7-cyano-7-deazaguanine reductase, N-terminal domain

Domain ID domain_id	1gtpM01
Class class	1 — Mainly Alpha
Architecture architecture	10 — Orthogonal Bundle
Topology topology	286 — GTP Cyclohydrolase I; Chain A, domain 1
Homologous superfamily homologous superfamily	10 — GTP cyclohydrolase I, N-terminal domain

Domain ID domain_id	1gtpM02
Class class	3 — Alpha Beta
Architecture architecture	30 — 2-Layer Sandwich
Topology topology	1130 — GTP Cyclohydrolase I, domain 2
Homologous superfamily homologous superfamily	10 — GTP cyclohydrolase I, C-terminal domain/NADPH-dependent 7-cyano-7-deazaguanine reductase, N-terminal domain

Domain ID domain_id	1gtpN01
Class class	1 — Mainly Alpha
Architecture architecture	10 — Orthogonal Bundle
Topology topology	286 — GTP Cyclohydrolase I; Chain A, domain 1
Homologous superfamily homologous superfamily	10 — GTP cyclohydrolase I, N-terminal domain

Domain ID domain_id	1gtpN02
Class class	3 — Alpha Beta
Architecture architecture	30 — 2-Layer Sandwich
Topology topology	1130 — GTP Cyclohydrolase I, domain 2
Homologous superfamily homologous superfamily	10 — GTP cyclohydrolase I, C-terminal domain/NADPH-dependent 7-cyano-7-deazaguanine reductase, N-terminal domain

Domain ID domain_id	1gtpO01
Class class	1 — Mainly Alpha
Architecture architecture	10 — Orthogonal Bundle
Topology topology	286 — GTP Cyclohydrolase I; Chain A, domain 1
Homologous superfamily homologous superfamily	10 — GTP cyclohydrolase I, N-terminal domain

Domain ID domain_id	1gtpO02
Class class	3 — Alpha Beta
Architecture architecture	30 — 2-Layer Sandwich
Topology topology	1130 — GTP Cyclohydrolase I, domain 2
Homologous superfamily homologous superfamily	10 — GTP cyclohydrolase I, C-terminal domain/NADPH-dependent 7-cyano-7-deazaguanine reductase, N-terminal domain

Domain ID domain_id	1gtpP01
Class class	1 — Mainly Alpha
Architecture architecture	10 — Orthogonal Bundle
Topology topology	286 — GTP Cyclohydrolase I; Chain A, domain 1
Homologous superfamily homologous superfamily	10 — GTP cyclohydrolase I, N-terminal domain

Domain ID domain_id	1gtpP02
Class class	3 — Alpha Beta
Architecture architecture	30 — 2-Layer Sandwich
Topology topology	1130 — GTP Cyclohydrolase I, domain 2
Homologous superfamily homologous superfamily	10 — GTP cyclohydrolase I, C-terminal domain/NADPH-dependent 7-cyano-7-deazaguanine reductase, N-terminal domain

Domain ID domain_id	1gtpQ01
Class class	1 — Mainly Alpha
Architecture architecture	10 — Orthogonal Bundle
Topology topology	286 — GTP Cyclohydrolase I; Chain A, domain 1
Homologous superfamily homologous superfamily	10 — GTP cyclohydrolase I, N-terminal domain

Domain ID domain_id	1gtpQ02
Class class	3 — Alpha Beta
Architecture architecture	30 — 2-Layer Sandwich
Topology topology	1130 — GTP Cyclohydrolase I, domain 2
Homologous superfamily homologous superfamily	10 — GTP cyclohydrolase I, C-terminal domain/NADPH-dependent 7-cyano-7-deazaguanine reductase, N-terminal domain

Domain ID domain_id	1gtpR01
Class class	1 — Mainly Alpha
Architecture architecture	10 — Orthogonal Bundle
Topology topology	286 — GTP Cyclohydrolase I; Chain A, domain 1
Homologous superfamily homologous superfamily	10 — GTP cyclohydrolase I, N-terminal domain

Domain ID domain_id	1gtpR02
Class class	3 — Alpha Beta
Architecture architecture	30 — 2-Layer Sandwich
Topology topology	1130 — GTP Cyclohydrolase I, domain 2
Homologous superfamily homologous superfamily	10 — GTP cyclohydrolase I, C-terminal domain/NADPH-dependent 7-cyano-7-deazaguanine reductase, N-terminal domain

Domain ID domain_id	1gtpS01
Class class	1 — Mainly Alpha
Architecture architecture	10 — Orthogonal Bundle
Topology topology	286 — GTP Cyclohydrolase I; Chain A, domain 1
Homologous superfamily homologous superfamily	10 — GTP cyclohydrolase I, N-terminal domain

Domain ID domain_id	1gtpS02
Class class	3 — Alpha Beta
Architecture architecture	30 — 2-Layer Sandwich
Topology topology	1130 — GTP Cyclohydrolase I, domain 2
Homologous superfamily homologous superfamily	10 — GTP cyclohydrolase I, C-terminal domain/NADPH-dependent 7-cyano-7-deazaguanine reductase, N-terminal domain

Domain ID domain_id	1gtpT01
Class class	1 — Mainly Alpha
Architecture architecture	10 — Orthogonal Bundle
Topology topology	286 — GTP Cyclohydrolase I; Chain A, domain 1
Homologous superfamily homologous superfamily	10 — GTP cyclohydrolase I, N-terminal domain

Domain ID domain_id	1gtpT02
Class class	3 — Alpha Beta
Architecture architecture	30 — 2-Layer Sandwich
Topology topology	1130 — GTP Cyclohydrolase I, domain 2
Homologous superfamily homologous superfamily	10 — GTP cyclohydrolase I, C-terminal domain/NADPH-dependent 7-cyano-7-deazaguanine reductase, N-terminal domain

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Unit-cell length a length_a	204.200 Å
Unit-cell length b length_b	210.400 Å
Unit-cell length c length_c	71.800 Å
Unit-cell angle α angle_alpha	90.00 °
Unit-cell angle β angle_beta	95.80 °
Unit-cell angle γ angle_gamma	90.00 °
Molecules per unit cell Z z_pdb	40

Space group space_group	P 1 21 1
Space-group number int_tables_number	4
Crystal system crystal_system	—

Resolution resolution	3.000 Å
Low-resolution limit resolution_low	6.000 Å
R factor r_factor	0.1890
R_work r_work	0.1890
R_free r_free	—

GTP CYCLOHYDROLASE I

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

GTP CYCLOHYDROLASE I

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

1gtp__assembly_1__model_1

1gtp__assembly_1__model_1 | I(q)

1gtp__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 (3)

Entity 1 Entity 1 polymer

Polymer Polymer

Source Source

Entity 2 Entity 2 non-polymer

Entity 3 Entity 3 water

6. Fold Classification (SCOP + CATH) 60 domains

SCOP 2.08 (20 domains)

CATH v4.4 (40 domains)

7. Citations (1)

GTP CYCLOHYDROLASE I

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

GTP CYCLOHYDROLASE I

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

1gtp__assembly_1__model_1

1gtp__assembly_1__model_1 | I(q)

1gtp__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 (3)

Entity 1 Entity 1 polymer

Polymer Polymer

Source Source

Entity 2 Entity 2 non-polymer

Entity 3 Entity 3 water

6. Fold Classification (SCOP + CATH) 60 domains

SCOP 2.08 (20 domains)

CATH v4.4 (40 domains)

7. Citations (1)