1sp0: Difference between revisions

[[Image:1sp0.jpg|left|200px]]

'''Solution Structure of apoCox11'''

Cytochrome c oxidase assembly process involves many accessory proteins including Cox11, which is a copper-binding protein required for Cu incorporation into the Cu(B) site of cytochrome c oxidase. In a genome wide search, a number of Cox11 homologs are found in all of the eukaryotes with complete genomes and in several Gram-negative bacteria. All of them possess a highly homologous soluble domain and contain an N-terminal fragment that anchors the protein to the membrane. An anchor-free construct of 164 amino acids was obtained from Sinorhizobium meliloti, and the first structure of this class of proteins is reported here. The apoform has an immunoglobulin-like fold with a novel type of beta-strand organization. The copper binding motif composed of two highly conserved cysteines is located on one side of the beta-barrel structure. The apoprotein is monomeric in the presence of dithiothreitol, whereas it dimerizes in the absence of the reductant. When copper(I) binds, NMR and extended x-ray absorption fine structure (EXAFS) data indicate a dimeric protein state with two thiolates bridging two copper(I) ions. The present results advance the knowledge on the poorly understood molecular aspects of cytochrome c oxidase assembly.

1SP0 is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Sinorhizobium_meliloti Sinorhizobium meliloti]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1SP0 OCA].  

''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sat May  3 08:58:15 2008''