The amino acid sequence of vanillin-binding site of transient receptor potential vanilloid type 1 from rat, Leu<sup>544</sup>–Tyr<sup>553</sup>, was extracted and hybridized with His-tag. The hexadecamer invariant chain peptide, Leu-Ala-Met-Gly-Trp-Thr-Asn-Met-Leu-Tyr-His-His-His-His-His-His (<b>VBH</b>), was prepared by solid-phase peptide synthesis. Circular dichroic spectral measurements determined the α-helix content to be 17%, which was consistent to that of short peptides. In a combined use of thiol-derivatized nitrilotriacetic acid (s-NTA) monolayers, the His-tag successfully attached the whole peptide on gold substrate surfaces through Ni<sup>2+</sup>-chelation (<i>Γ</i><sub><b>VBH</b></sub> = 224 ± 120 pmol cm<sup>-2</sup>, <i>n</i> = 8). Moreover, various surface analyses including atomic force microscopy imaging, FT-IR spectroscopy, and quartz-crystal microgravimetry (QCM) revealed self-assembly (SA) of <b>VBH</b> at the S-NTA monolayer surfaces. QCM measurements also showed that vanillin, the major component of natural vanilla flavoring, binds to <b>VBH</b> SAs (<i>K</i><sub>app</sub> = 2.7 × 10<sup>3</sup> M<sup>–1</sup>). The affinity of host–guest binding remains limited but possesses a certain degree of selectivity; for cases of structural analogs that give a pleasant flavor, acetophenone showed rather weak affinity (<i>K</i><sub>app</sub> = 2.8 × 10<sup>2</sup> M<sup>–1</sup>) whereas 4-heptanone did not bind at all. With these results <b>VBH</b> was concluded to be useful in vanillin sensing as a supramolecular affinity host.
|Translated title of the contribution||Synthesis and Self-Assembly of His-tag Hybrid of Substrate-Binging Short Domain in Transient Receptor Potential Vanilloid Type 1 for Vanillin Sensing Application|
|Number of pages||4|
|Journal||Transactions of the Materials Research Society of Japan|
|Publication status||Published - 2015|