title: Adsorption kinetics of an engineered gold binding Peptide by surface plasmon resonance spectroscopy and a quartz crystal microbalance.
abstract: The adsorption kinetics of an engineered gold binding peptide on gold surface was studied by using both quartz crystal microbalance (QCM) and surface plasmon resonance (SPR) spectroscopy systems. The gold binding peptide was originally selected as a 14-amino acid sequence by cell surface display and then engineered to have a 3-repeat form (3R-GBP1) with improved binding characteristics. Both sets of adsorption data for 3R-GBP1 were fit to Langmuir models to extract kinetics and thermodynamics parameters. In SPR, the adsorption onto the surface shows a biexponential behavior and this is explained as the effect of bimodal surface topology of the polycrystalline gold substrate on 3R-GBP1 binding. Depending on the concentration of the peptide, a preferential adsorption on the surface takes place with different energy levels. The kinetic parameters (e.g., K(eq) approximately 10(7) M(-1)) and the binding energy (approximately -8.0 kcal/mol) are comparable to synthetic-based self-assembled monolayers. The results demonstrate the potential utilization of genetically engineered inorganic surface-specific peptides as molecular substrates due to their binding specificity, stability, and functionality in an aqueous-based environment.
authors.affiliation: Material Science and Engineering, University of Washington, Seattle, Washington 98195, USA.
authors.forename: Candan
authors.initials: C
authors.lastname: Tamerler
authors.forename: Ersin Emre
authors.initials: EE
authors.lastname: Oren
authors.forename: Memed
authors.initials: M
authors.lastname: Duman
authors.forename: Eswaranand
authors.initials: E
authors.lastname: Venkatasubramanian
authors.forename: Mehmet
authors.initials: M
authors.lastname: Sarikaya
mesh_terms: D000327:Adsorption; D000595:Amino Acid Sequence; D003460:Crystallization; D006046:Gold / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D018625:Microscopy, Atomic Force; D008969:Molecular Sequence Data; D010455:Peptides / Q000737:chemistry*; D011791:Quartz / Q000737:chemistry*; D020349:Surface Plasmon Resonance; D013499:Surface Properties
chemical_list: D010455:Peptides; D011791:Quartz; D006046:Gold