pH-dependent behavior of surface-immobilized artificial leucine zipper proteins
The coiled-coil protein motif occurs in over 200 proteins and has generated interest for a range of applications requiring surface immobilization of the constituent peptides. This paper describes an investigation of the environment-responsive behavior of a monolayer of surface-immobilized artificial...
Veröffentlicht in: | Langmuir : the ACS journal of surfaces and colloids. - 1992. - 20(2004), 18 vom: 31. Aug., Seite 7747-52 |
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1. Verfasser: | |
Weitere Verfasser: | , , , , , , |
Format: | Aufsatz |
Sprache: | English |
Veröffentlicht: |
2004
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Zugriff auf das übergeordnete Werk: | Langmuir : the ACS journal of surfaces and colloids |
Schlagworte: | Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. Coated Materials, Biocompatible Membrane Proteins Quartz 14808-60-7 Gold 7440-57-5 |
Zusammenfassung: | The coiled-coil protein motif occurs in over 200 proteins and has generated interest for a range of applications requiring surface immobilization of the constituent peptides. This paper describes an investigation of the environment-responsive behavior of a monolayer of surface-immobilized artificial proteins, which are known to assemble to form coiled-coil structures in bulk solution. An extended version of the quartz crystal microbalance (QCM-D) and surface plasmon resonance (SPR) are independently employed to characterize the adsorption of the proteins to a gold surface. The data suggest that the molecules arrange in a closely packed layer orientated perpendicular to the surface. QCM-D measurements are also employed to measure pH-induced changes in the resonant frequency (f) and the energy dissipation factor (D) of a gold-coated quartz crystal functionalized with the formed monolayer. Exposure of the protein monolayer to a pH 4.5 solution results in a shift of 43 Hz in f and a shift of -0.7 x 10(-6) in D as compared to pH 7.4. In contrast, increasing the pH to 11.2, results in f and D shifts of -17 Hz and 0.6 x 10(-6), respectively. The magnitude of the observed shifts suggests that the proteins form a rigid layer at low pH that can be hydrated to a fluid layer as the pH is increased. These observations correlate with spectroscopic changes that indicate a reduction in the helical content of the protein in bulk solutions of high pH |
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Beschreibung: | Date Completed 10.03.2006 Date Revised 15.11.2006 published: Print Citation Status MEDLINE |
ISSN: | 1520-5827 |