PARENT SESSION
Posters P5A Type II reaction centres : Structure. Abstracts (289-312)

Exploring the origin and evolution of oxygen-evolving extrinsic proteins by genome-wide bioinformatic studies. Javier De Las Rivas^*,1, ¹ Consejo Superior de Investigaciones Cientificas (CSIC), Salamanca, Spain

ABSTRACT- In recent years biomolecular sciences have been pushed forward by the overwhelming advance of new biotechnological high-throughput experimental methods that have open the fields of genomics and proteomics. Together to these experimental methods, that are generating vasts amounts of data, there is a strong interest, necessity and effort in developing the related field of bioinformatics. Computational methods allow exploration and analyses of genome-wide information. We have undertaken several bioinformatic methods and strategies to study the chloroplast proteome with particular focus on the families of the extrinsic proteins associated to Photosystem II, the water splitting and oxygen evolving enzyme. The appearance of oxygenic photosynthesis was a key event in the evolution of our green biosphere. Oxygen in the atmosphere is generally believed to come from the biomolecular water-splitting reaction that occurs in oxyphotosynthetic organisms catalysed by the oxygen evolving centre (OEC) of Photosystem II. Using knowledge from complete genomes in current databases, we have investigated the nature and composition of the extrinsic proteins forming the OECs of different organisms. The manganese stabilizing protein, PsbO, is present in all known oxyphototrophs and we map its structural changes along evolution and its association with different lumenal extrinsic subunits within PSII. This analysis traces the evolution of the extrinsic proteins from ancient cyanobacteria to higher plants and gives hints about the ancestral form of the OEC.
De Las Rivas J., Lozano J. and Ortíz A. (2002). Comparative analysis of cpDNA genomes: functional annotation, genome-based phylogeny and deduced evolutionary patters.Genome Research 12:567-583.
De Las Rivas J., Balsera M. and Barber J. (2004). Evolution of oxygenic photosynthesis: genome-wide analysis of the OEC extrinsic proteins. Trends in Plant Sicences 9: 18-25

KEY WORDS: oxygen evolving complex, bioinformatics, photosystem II, PsbO