Structure of PDB 1k2r Chain A

Receptor sequence

>1k2rA (length=407) Species: 10116 (Rattus norvegicus)

RFLKVKNWETDVVLTDTLHLKSTLETGCTEHICMGSIMLPTKDQLFPLAK
EFLDQYYSSIKRFGSKAHMDRLEEVNKEIESTSTYQLKDTELIYGAKHAW
RNASRCVGRIQWSKLQVFDARDCTTAHGMFNYICNHVKYATNKGNLRSAI
TIFPQRTDGKHDFRVWNSQLIRYAGYKQPDGSTLGDPANVQFTEICIQQG
WKAPRGRFDVLPLLLQANGNDPELFQIPPELVLEVPIRHPKFDWFKDLGL
KWYGLPAVSNMLLEIGGLEFSACPFSGWYMGTEIGVRDYCDNSRYNILEE
VAKKMDLDMRKTSSLWKDQALVEINIAVLYSFQSDKVTIVDHHSATESFI
KHMENEYRCRGGCPADWVWIVPPMSGSITPVFHQEMLNYRLTPSFEYQPD
PWNTHVW

3D structure

• PDB: 1k2r Crystal structure of constitutive endothelial nitric oxide synthase: a paradigm for pterin function involving a novel metal center
• Chain: A
• Resolution: 2.15 Å

Enzymatic activity

• Catalytic site (original residue number in PDB): C415 R418 W587 E592
• Catalytic site (residue number reindexed from 1): C106 R109 W278 E283
• Enzyme Commision number: 1.14.13.39: nitric-oxide synthase (NADPH).

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	HEM	A	W409 C415 V416 M570 F584 S585 W587 E592 W678 Y706	W100 C106 V107 M261 F275 S276 W278 E283 W369 Y397
BS02	H4B	A	S334 M336 R596 V677 W678	S36 M38 R287 V368 W369
BS03	NRG	A	Q478 P565 V567 S585 G586 W587 Y588 E592 D597	Q169 P256 V258 S276 G277 W278 Y279 E283 D288	BindingDB: IC50=5000nM,Ki=610nM
BS04	ZN	A	C326 C331	C28 C33
BS05	H4B	A	W676 F691 H692 E694	W367 F382 H383 E385

Gene Ontology

Molecular Function

• GO:0004517 nitric-oxide synthase activity
• GO:0020037 heme binding

Biological Process

• GO:0006809 nitric oxide biosynthetic process

External links

• PDB: RCSB:1k2r, PDBe:1k2r, PDBj:1k2r
• PDBsum: 1k2r
• UniProt: P29476|NOS1_RAT Nitric oxide synthase 1 (Gene Name=Nos1)