Abstract
ABSTRACTPhotoactive yellow protein (PYP) is a small cytosolic photoreceptor that actuates the negative phototactic response in its host organism Halorhodospira halophila. It has an optical absorption maximum at 446 nm (blue light). We report an initial study of the photocycle of PYP at the single molecule level using “high enhancement factor” surface-enhanced Raman scattering (SERS)-active nanostructures with 514 nm laser excitation. The SERS-active “nanometal-on-semiconductor” structures are prepared employing a redox technique on thin germanium films, coated on glass slides. Single molecule spectra are observed in terms of sudden appearance of discernable Raman peaks with spectral fluctuations. The single molecule spectra capture protonation, photo-isomerization, and H-bond breaking - the steps that are instrumental in the photocycle of PYP. This is indicative of single PYP molecules diffusing to high-enhancement-factor SERS sites, and undergoing photo-cycle under 514 nm excitation.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
