Structure of PDB 1n3r Chain B

Receptor sequence

>1n3rB (length=221) Species: 562 (Escherichia coli)

PSLSKEAALVHEALVARGLETPLRPPVHEMDNETRKSLIAGHMTEIMQLL
NLDLADDSLMETPHRIAKMYVDEIFSGLDYANFPKITLIENKMKVDEMVT
VRDITLTSTCESHFVTIDGKATVAYIPKDSVIGLSKINRIVQFFAQRPQV
QERLTQQILIALQTLLGTNNVAVSIDAVHYCVKARGIRDATSATTTTSLG
GLFKSSQNTRHEFLRAVRHHN

3D structure

• PDB: 1n3r Biosynthesis of Pteridines. Reaction Mechanism of GTP Cyclohydrolase I
• Chain: B
• Resolution: 2.8 Å

Enzymatic activity

• Catalytic site (original residue number in PDB): C110 E111 S112 H113 Q151 H179 C181
• Catalytic site (residue number reindexed from 1): C110 E111 S112 H113 Q151 H179 C181
• Enzyme Commision number: 3.5.4.16: GTP cyclohydrolase I.

Interaction with ligand

Site #	Ligand	Ligand chain	Binding residues on receptor (original residue number in PDB)	Binding residues on receptor (residue number reindexed from 1)	Binding affinity
BS01	GTP	B	T87 G133 L134 S135 K136 R139	T87 G133 L134 S135 K136 R139
BS02	GTP	B	S112 H113 V150 E152 R185	S112 H113 V150 E152 R185

Gene Ontology

Molecular Function

• GO:0003934 GTP cyclohydrolase I activity
• GO:0005525 GTP binding
• GO:0008270 zinc ion binding
• GO:0016787 hydrolase activity
• GO:0042802 identical protein binding
• GO:0046872 metal ion binding

Biological Process

• GO:0006729 tetrahydrobiopterin biosynthetic process
• GO:0006730 one-carbon metabolic process
• GO:0008616 queuosine biosynthetic process
• GO:0046654 tetrahydrofolate biosynthetic process

Cellular Component

• GO:0005737 cytoplasm
• GO:0005829 cytosol
• GO:0032991 protein-containing complex

External links

• PDB: RCSB:1n3r, PDBe:1n3r, PDBj:1n3r
• PDBsum: 1n3r
• PubMed: 12559918
• UniProt: P0A6T5|GCH1_ECOLI GTP cyclohydrolase 1 (Gene Name=folE)