Hemocyanin

Hemocyanin, copper containing domain
Single oxygenated functional unit from the hemocyanin of an octopus
Identifiers
Symbol	Hemocyanin_M
Pfam	PF00372
InterPro	IPR000896
PROSITE	PDOC00184
SCOP2	1lla / SCOPe / SUPFAM
Available protein structures: Pfam   structures / ECOD   PDB RCSB PDB; PDBe; PDBj PDBsum structure summary PDB 1oxy :110-373 1nol :110-373 1lla :110-373 1ll1 :110-373 1hc1A:136-393 1hcyD:136-393 1hc6B:136-393 1hc4C:136-393 1hc3C:136-393 1hc5C:136-393 1hc2C:136-393

Hemocyanin, all-alpha domain
Crystal structure of hexameric haemocyanin from Panulirus interruptus refined at 3.2 angstroms resolution
Identifiers
Symbol	Hemocyanin_N
Pfam	PF03722
InterPro	IPR005204
PROSITE	PDOC00184
SCOP2	1lla / SCOPe / SUPFAM
Available protein structures: Pfam   structures / ECOD   PDB RCSB PDB; PDBe; PDBj PDBsum structure summary

Hemocyanin, ig-like domain
crystallographic analysis of oxygenated and deoxygenated states of arthropod hemocyanin shows unusual differences
Identifiers
Symbol	Hemocyanin_C
Pfam	PF03723
InterPro	IPR005203
PROSITE	PDOC00184
SCOP2	1lla / SCOPe / SUPFAM
Available protein structures: Pfam   structures / ECOD   PDB RCSB PDB; PDBe; PDBj PDBsum structure summary

Hemocyanins (also spelled haemocyanins and abbreviated Hc) are proteins that transport oxygen throughout the bodies of some invertebrate animals. These metalloproteins contain two copper atoms that reversibly bind a single oxygen molecule (O₂). They are second only to hemoglobin in frequency of use as an oxygen transport molecule. Unlike the hemoglobin in red blood cells found in vertebrates, hemocyanins are not confined in blood cells but are instead suspended directly in the hemolymph. Oxygenation causes a color change between the colorless Cu(I) deoxygenated form and the blue Cu(II) oxygenated form.^[1]