INBA   12521
INSTITUTO DE INVESTIGACIONES EN BIOCIENCIAS AGRICOLAS Y AMBIENTALES
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Redox-dependent degradation of PsbO is performed by Deg proteases
Autor/es:
IRMA N. ROBERTS; HELDER MIRANDA; LAM XUAN TAM; THOMAS KIESELBACH; CHRISTIANE FUNK
Lugar:
Lucca
Reunión:
Conferencia; Mitochondria & Chloroplasts Gordon Research Seminar and Mitochondria & Chloroplasts Gordon Research Conference; 2010
Resumen:
Redox-dependent degradation of PsbO is performed by Deg proteases The widely distributed members of the Deg/HtrA protease family play in important role in proteolysis of misfolded and damaged proteins; for some members of this family also chaperone activity has been demonstrated. Here we show that Deg proteases are able to degrade reduced PsbO protein, the extrinsic protein of the Photosystem II oxygen evolving complex in spinach and Synechocystis sp. PCC 6803. This PsbO protein is known to be stable in its oxidized form; however, after reduction it becomes a substrate for Deg proteases in vitro. While reduced non-native (spinach) PsbO is degraded by defined cuts, recombinant HhoA degrades native substrate (reduced PsbO of Synechocystis sp. PCC 6803) continuously. PsbO bound to PSII is degraded to a lesser extent than unbound PsbO. However, all three cyanobacterial Deg proteases (HhoA, HhoB and HtrA) copurified with Photosystem II of Synechocystis sp. PCC 6803.