How the Local Geometry of the Cu-Binding Site Determines the Thermal Stability of Blue Copper Proteins

Identifying the factors that govern the thermal resistance of cupredoxins is essential for understanding their folding and stability, and for improving our ability to design highly stable enzymes with potential biotechnological applications. Here, we show that the thermal unfolding of plastocyanins...

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Detalles Bibliográficos
Autores: Chaboy, Jesús, Díaz Moreno, Sofía, Díaz Moreno, Irene, Rosa Acosta, Miguel Ángel de la, Díaz Quintana, Antonio Jesús
Tipo de recurso: artículo
Estado:Versión enviada para evaluación y publicación
Fecha de publicación:2011
País:España
Institución:Universidad de Sevilla (US)
Repositorio:idUS. Depósito de Investigación de la Universidad de Sevilla
OAI Identifier:oai:idus.us.es:11441/66489
Acceso en línea:http://hdl.handle.net/11441/66489
https://doi.org/10.1016/j.chembiol.2010.12.006
Access Level:acceso abierto
Palabra clave:Cupredoxin
Enzymes
Biotechnological application
Plastocyanin
Synechocystis
Phormidium
Cyanobacteria
Descripción
Sumario:Identifying the factors that govern the thermal resistance of cupredoxins is essential for understanding their folding and stability, and for improving our ability to design highly stable enzymes with potential biotechnological applications. Here, we show that the thermal unfolding of plastocyanins from two cyanobacteria—the mesophilic Synechocystis and the thermophilic Phormidium—is closely related to the short-range structure around the copper center. Cu K-edge X-ray absorption spectroscopy shows that the bond length between Cu and the S atom from the cysteine ligand is a key structural factor that correlates with the thermal stability of the cupredoxins in both oxidized and reduced states. These findings were confirmed by an additional study of a site-directed mutant of Phormidium plastocyanin showing a reverse effect of the redox state on the thermal stability of the protein.