Related Experiment Videos
The structure of arthropod hemocyanins
Science (New York, N.Y.)
|August 9, 1985
Summary
Hemocyanins, copper proteins carrying oxygen in arthropods, show conserved sequences across diverse species. This suggests a shared, ancient polypeptide structure dating back over 540 million years.
Area of Science:
- Biochemistry
- Evolutionary Biology
- Structural Biology
Background:
- Hemocyanins are crucial oxygen-transporting proteins found in arthropods and molluscs.
- These proteins are large, multi-subunit complexes containing copper.
Purpose of the Study:
- To compare amino acid sequences of arthropod hemocyanins.
- To investigate the evolutionary conservation of hemocyanin structure.
Main Methods:
- Comparative analysis of amino acid sequence data from seven different hemocyanin subunits.
- Comparison with existing X-ray crystallography data for spiny lobster hemocyanin structure.
Main Results:
- High conservation of amino acid residues and extensive regions of identity were observed among arthropod hemocyanins.
- The conserved sequences closely matched the three-domain structure of spiny lobster hemocyanin.
- Remarkable identity was found in the second domain, crucial for copper-binding and oxygen transport.
Conclusions:
- The polypeptide architecture of hemocyanins is highly conserved across arthropods.
- This conserved structure is ancient, predating the divergence of crustaceans and chelicerates over 540 million years ago.