Naslov
Intrinsic fluorescence in non-aromatic peptide structures is induced by collective vibrations, charge reorganisation and short hydrogen bonds, as shown in a new glutamine-related structure

Autori
Stephens, Amberley D. ; Qaisrani, Muhammad Nawaz ; Ruggiero, Michael T. ; Jones, Saul T.E. ; Poli, Emiliano ; Bond, Andrew D. ; Woodhams, Philippa J. ; Kleist, Elyse M. ; Grisanti, Luca ; Gebauer, Ralph ; Zeitler, J. Axel ; Credgington, Dan ; Hassanali, Ali ; Kaminski Schierle, Gabriele S.

Izvornik
BiorXiv

Vrsta, podvrsta
Ostale vrste radova, rukopis

Godina
2020

Ključne riječi
fluorescence, hydrogen bonds, peptide

Sažetak
Disentangling the origin of the optical activity of non-aromatic proteins is challenging due to their size and thus their high computational requisites. Here we show, in a much smaller model system, that the single amino acid glutamine undergoes a chemical transformation leading to an unreported glutamine-like structure which has a similar broad absorption spectrum reported previously for non-aromatic proteins. We further show computationally that the optical activity of the glutamine-like structure is directly coupled to short-hydrogen bonds, but also displays charge and vibrational fluctuations, the latter of which are also present in less optically active structures such as in L-glutamine. Since experimentally the glutamine-like structure is the brightest structure, we conclude that short-hydrogen bonds are the ones responsible for the large Stokes shift observed in optically active non-aromatic proteins.

Izvorni jezik
Engleski

Znanstvena područja
Interdisciplinarne prirodne znanosti

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