Building Polyelectrolyte Multilayers with Calmodulin : A Neutron and X-ray Reflectivity Study

We have studied the formation and functional properties of polyelectrolyte multilayers where calmodulin (CaM) is used as a polyanion. CaM is known to populate distinct conformational states upon binding Ca2+ and small ligand molecules. Therefore, we have also probed the effects of Ca2+ ions and trif...

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Veröffentlicht in:Langmuir : the ACS journal of surfaces and colloids. - 1992. - 33(2017), 16 vom: 25. Apr., Seite 3982-3990
1. Verfasser: Cinar, Süleyman (VerfasserIn)
Weitere Verfasser: Möbitz, Simone, Al-Ayoubi, Samy, Seidlhofer, Beatrix-Kamelia, Czeslik, Claus
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2017
Zugriff auf das übergeordnete Werk:Langmuir : the ACS journal of surfaces and colloids
Schlagworte:Journal Article Research Support, Non-U.S. Gov't
Beschreibung
Zusammenfassung:We have studied the formation and functional properties of polyelectrolyte multilayers where calmodulin (CaM) is used as a polyanion. CaM is known to populate distinct conformational states upon binding Ca2+ and small ligand molecules. Therefore, we have also probed the effects of Ca2+ ions and trifluoperazine (TFP) as ligand molecule on the interfacial structures. Multilayers with the maximum sequence PEI-(PSS-PAH)x-CaM-PAH-CaM-PAH have been deposited on silicon wafers and characterized by X-ray and neutron reflectometry. From the analysis of all data, several remarkable conclusions can be drawn. When CaM is deposited for the second time, a much thicker sublayer is produced than in the first CaM deposition step. However, upon rinsing with PAH, very thin CaM-PAH sublayers remain. There are no indications that ligand TFP can be involved in the multilayer buildup due to strong CaM-PAH interactions. However, there is a significant increase in the multilayer thickness upon removal of Ca2+ ions from holo-CaM and an equivalent decrease in the multilayer thickness upon subsequent saturation of apo-CaM with Ca2+ ions. Presumably, CaM can still be toggled between an apo and a holo state, when it is embedded in polyelectrolyte multilayers, providing an approach to design bioresponsive interfaces
Beschreibung:Date Completed 09.07.2018
Date Revised 09.07.2018
published: Print-Electronic
Citation Status PubMed-not-MEDLINE
ISSN:1520-5827
DOI:10.1021/acs.langmuir.7b00651