6533b835fe1ef96bd129f6e7
RESEARCH PRODUCT
Cupredoxin-like domains in haemocyanins
Jürgen MarklThomas R. M. BarendsElmar JaenickeKay BüchlerHeinz Deckersubject
Models MolecularCopper proteinmedicine.medical_treatmentGastropodaMolecular Sequence DataBiologyCrystallography X-RayBiochemistryAzurinmedicineAnimalsAmino Acid SequenceBinding siteMolecular BiologyPeptide sequencePhylogenychemistry.chemical_classificationBinding SitesSequence Homology Amino AcidOxygen transportActive siteHemocyaninCell BiologyAnatomyProtein Structure TertiaryAmino acidMolecular WeightBiochemistrychemistryHemocyaninsbiology.proteinAzurinCopperdescription
Haemocyanins are multimeric oxygen transport proteins, which bind oxygen to type 3 copper sites. Arthropod haemocyanins contain 75-kDa subunits, whereas molluscan haemocyanins contain 350–400-kDa subunits comprising seven or eight different 50 kDa FUs (functional units) designated FU-a to FU-h, each with an active site. FU-h possesses a tail of 100 amino acids not present in the other FUs. In the present study we show by X-ray crystallography that in FU-h of KLH1 (keyhole-limpet-haemocyanin isoform 1) the structure of the tail domain is cupredoxin-like but contains no copper. The copper-free domain 3 in arthropod haemocyanin subunits has also recently been reinterpreted as being cupredoxin-like. We propose that the cupredoxin-like domain in both haemocyanin types once served to upload copper to the active site of the oxygen-binding domain.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2010-03-15 |