English   español  
Please use this identifier to cite or link to this item: http://hdl.handle.net/10261/178714
Share/Impact:
Statistics
logo share SHARE logo core CORE   Add this article to your Mendeley library MendeleyBASE

Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL
Exportar a otros formatos:
Title

Photosynthetic cytochrome c550

AuthorsRoncel, Mercedes; Kirilovsky, D.; Guerrero, Fernando ; Serrano, Aurelio ; Ortega, José M.
KeywordsDiatoms
Photosystem II
psbV gene product
Red algae
Cyanobacteria
Cytochrome c550
Issue Date2012
PublisherElsevier
CitationBiochimica et Biophysica Acta - Bioenergetics 1817: 1152- 1163 (2012)
AbstractCytochrome c550 (cyt c550) is a membrane component of the PSII complex in cyanobacteria and some eukaryotic algae, such as red and brown algae. Cyt c550 presents a bis-histidine heme coordination which is very unusual for monoheme c-type cytochromes. In PSII, the cyt c550 with the other extrinsic proteins stabilizes the binding of Cl¿ and Ca2+ ions to the oxygen evolving complex and protects the Mn4Ca cluster from attack by bulk reductants. The role (if there is one) of the heme of the cyt c550 is unknown. The low midpoint redox potential (Em) of the purified soluble form (from ¿250 to ¿314 mV) is incompatible with a redox function in PSII. However, more positive values for the Em have been obtained for the cyt c550 bound to the PSII. A very recent work has shown an Em value of +200 mV. These data open the possibility of a redox function for this protein in electron transfer in PSII. Despite the long distance (22 Å) between cyt c550 and the nearest redox cofactor (Mn4Ca cluster), an electron transfer reaction between these components is possible. Some kind of protective cycle involving a soluble redox component in the lumen has also been proposed. The aim of this article is to review previous studies done on cyt c550 and to consider its function in the light of the new results obtained in recent years. The emphasis is on the physical properties of the heme and its redox properties. This article is part of a Special Issue entitled: Photosynthesis Research for Sustainability: from Natural to Artificial
URIhttp://hdl.handle.net/10261/178714
Identifiersdoi: 10.1016/j.bbabio.2012.01.008
issn: 0005-2728
Appears in Collections:(IBVF) Artículos
Files in This Item:
File Description SizeFormat 
Preprint BBA2012.pdf1,51 MBAdobe PDFThumbnail
View/Open
Show full item record
Review this work
 

Related articles:


WARNING: Items in Digital.CSIC are protected by copyright, with all rights reserved, unless otherwise indicated.