Structure of PDB 1cqx Chain A

Receptor sequence

>1cqxA (length=403) Species: 106590 (Cupriavidus necator)

MLTQKTKDIVKATAPVLAEHGYDIIKCFYQRMFEAHPELKNVFNMAHQEQ
GQQQQALARAVYAYAENIEDPNSLMAVLKNIANKHASLGVKPEQYPIVGE
HLLAAIKEVLGNAATDDIISAWAQAYGNLADVLMGMESELYERSAEQPGG
WKGWRTFVIREKRPESDVITSFILEPADGGPVVNFEPGQYTSVAIDVPAL
GLQQIRQYSLSDMPNGRTYRISVKREGGGPQPPGYVSNLLHDHVNVGDQV
KLAAPYGSFHIDVDAKTPIVLISGGVGLTPMVSMLKVALQAPPRQVVFVH
GARNSAVHAMRDRLREAAKTYENLDLFVFYDQPLPEDVQGRDYDYPGLVD
VKQIEKSILLPDADYYICGPIPFMRMQHDALKNLGIHEARIHYEVFGPDL
FAE

3D structure

• PDB: 1cqx Crystal structure of the flavohemoglobin from Alcaligenes eutrophus at 1.75 A resolution.
• Chain: A
• Resolution: 1.75 Å

Enzymatic activity

• Enzyme Commision number: 1.14.12.17: nitric oxide dioxygenase.

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	F43 N44 I81 H85 L88 V90 Q94 Y95 V98 Y126 L129 A130 L133	F43 N44 I81 H85 L88 V90 Q94 Y95 V98 Y126 L129 A130 L133
BS02	FAD	A	A46 H47 Y190 R206 Q207 Y208 S209 S222 E226 Q231 P232 G234 Y235 V236 S237 V395 G397 P398	A46 H47 Y190 R206 Q207 Y208 S209 S222 E226 Q231 P232 G234 Y235 V236 S237 V395 G397 P398

Gene Ontology

Molecular Function

• GO:0005344 oxygen carrier activity
• GO:0008941 nitric oxide dioxygenase NAD(P)H activity
• GO:0016491 oxidoreductase activity
• GO:0019825 oxygen binding
• GO:0020037 heme binding
• GO:0046872 metal ion binding
• GO:0071949 FAD binding

Biological Process

• GO:0009636 response to toxic substance
• GO:0015671 oxygen transport
• GO:0046210 nitric oxide catabolic process
• GO:0051409 response to nitrosative stress
• GO:0071500 cellular response to nitrosative stress

Cellular Component

• GO:0005737 cytoplasm

External links

• PDB: RCSB:1cqx, PDBe:1cqx, PDBj:1cqx
• PDBsum: 1cqx
• PubMed: 8557026
• UniProt: P39662|HMP_CUPNH Flavohemoprotein (Gene Name=hmp)