Extensive unfolding of the C-LytA choline-binding module by submicellar concentrations of sodium dodecyl sulphate

We have investigated the stability of the choline-binding module C-LytA against sodium dodecyl sulphate (SDS)-induced unfolding at pH 7.0 and 20 C. A major intermediate with an unfolded N-terminal region accumulates at around 0.75 mM SDS, whereas 2.0 mM SDS was sufficient for a complete unfolding. T...

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Detalles Bibliográficos
Autores: Maestro García-Donas, Beatriz, Sanz, Jesús M.
Tipo de recurso: artículo
Fecha de publicación:2006
País:España
Institución:Universidad Miguel Hernández de Elche
Repositorio:REDIUMH. Depósito Digital de la UMH
OAI Identifier:oai:dspace.umh.es:11000/30953
Acceso en línea:https://hdl.handle.net/11000/30953
Access Level:acceso abierto
Palabra clave:Choline-binding module
SDS denaturation
Protein stability
Repeat proteins
Affinity tag
Descripción
Sumario:We have investigated the stability of the choline-binding module C-LytA against sodium dodecyl sulphate (SDS)-induced unfolding at pH 7.0 and 20 C. A major intermediate with an unfolded N-terminal region accumulates at around 0.75 mM SDS, whereas 2.0 mM SDS was sufficient for a complete unfolding. This might be the first report of a protein being extensively unfolded by submicellar concentrations of SDS, occurring through formation of detergent clusters on the protein surface. All transitions were reversible upon SDS complexation with b-cyclodextrin, allowing the calculation of thermodynamic parameters. A model for the unfolding of C-LytA by SDS is presented and compared to a previous denaturation scheme by guanidine hydrochloride.