|PROSITE documentation PDOC51485|
Among the blue copper proteins with a single type I (or "blue") mononuclear copper site, the plant-specific phytocyanins constitute a distinct subfamily that can be further subdivided into the families of uclacyanins, stellacyanins, plantacyanins, and early nodulins. Stellacyanins have a blue copper coordinated by two His, one Cys and one Gln. In plantacyanins and uclacyanins, the ligands of the type-I Cu sites are two His, one Cys and one Met [1,2,3,4]. Early nodulins lack amino acid residues that coordinate Cu, so they are believed to be involved in unknown processes without binding Cu . Phytocyanins are found in chloropasts of higher plants.
The phytocyanin domain has a core of seven polypeptide strands arranged as a β-sandwich comprising two β-sheets, β-sheet I and β-sheet II (see <PDB:1WS8>). β-sheet I consists of three β-strands and β-sheet II consists of four β-strands. A disulfide bridge close the metal center is characteristic for phytocyanins, in contrast to azurins, pseudoazurins, and plastocyanins, where a disulfide bond is located on the distal side of the β-barrel. This disuldide bridge may play a crucial role in maintaining the tertiary structure of the protein and/or the formation of the copper binding center because one of the His ligands of copper is followed directly by a bridging Cys residue [1,2,3,,4].
Some proteins known to contain a phytocyanin domain are listed below:
The profile we developed covers the entire phytocyanin domain.Last update:
April 2010 / First entry.
PROSITE method (with tools and information) covered by this documentation:
|1||Authors||Nersissian A.M. Immoos C. Hill M.G. Hart P.J. Williams G. Herrmann R.G. Valentine J.S.|
|Title||Uclacyanins, stellacyanins, and plantacyanins are distinct subfamilies of phytocyanins: plant-specific mononuclear blue copper proteins.|
|Source||Protein Sci. 7:1915-1929(1998).|
|2||Authors||Einsle O. Mehrabian Z. Nalbandyan R. Messerschmidt A.|
|Title||Crystal structure of plantacyanin, a basic blue cupredoxin from spinach.|
|Source||J. Biol. Inorg. Chem. 5:666-672(2000).|
|3||Authors||Xie Y. Inoue T. Miyamoto Y. Matsumura H. Kataoka K. Yamaguchi K. Nojini M. Suzuki S. Kai Y.|
|Title||Structural reorganization of the copper binding site involving Thr15 of mavicyanin from Cucurbita pepo medullosa (zucchini) upon reduction.|
|Source||J. Biochem. 137:455-461(2005).|
|4||Authors||Koch M. Velarde M. Harrison M.D. Echt S. Fischer M. Messerschmidt A. Dennison C.|
|Title||Crystal structures of oxidized and reduced stellacyanin from horseradish roots.|
|Source||J. Am. Chem. Soc. 127:158-166(2005).|
|5||Authors||Mashiguchi K. Asami T. Suzuki Y.|
|Title||Genome-wide identification, structure and expression studies, and mutant collection of 22 early nodulin-like protein genes in Arabidopsis.|
|Source||Biosci. Biotechnol. Biochem. 73:2452-2459(2009).|