Magnetic field effect in natural cryptochrome explored with model compound.
Shubhajit Paul1, Alexey S Kiryutin2,3, Jinping Guo4
1Institut für Analytische Chemie, Universität Leipzig, Linnéstr, 3, D-04103, Leipzig, Germany.
Scientific Reports
|September 21, 2017
Summary
This study reveals how cryptochrome proteins in animal retinas may use quantum effects for magnetic navigation. Experiments with a model compound (F10T) demonstrate this mechanism even at Earth's magnetic field.
Area of Science:
- Biophysics
- Quantum Biology
- Neuroethology
Background:
- Animals navigate using Earth's magnetic field.
- Cryptochrome proteins in the retina are hypothesized to be involved in magnetoreception via a light-dependent quantum effect.
- The precise biophysical mechanisms and spin dynamics within cryptochromes remain unclear.
Purpose of the Study:
- To investigate the magnetic field dependence of photochemical processes in cryptochrome.
- To elucidate the spin dynamics and energy-level mixing mechanisms at low magnetic fields.
- To validate a model compound (F10T) for understanding avian magnetoreception.
Main Methods:
- Utilized 1H photo-induced chemically induced dynamic nuclear polarization (photo-CIDNP) Nuclear Magnetic Resonance (NMR) spectroscopy.
- Studied the magnetic field dependence of the flavin-tryptophan dyad (F10T) model compound.
- Developed a theoretical model for low-field photo-CIDNP in F10T.
Main Results:
- Observed photo-CIDNP signals in F10T even at Earth's magnetic field strength (~0.05 mT).
- The theoretical model successfully described the energy-level mixing and spin dynamics at low magnetic fields.
- Demonstrated F10T as a suitable model for studying cryptochrome's function.
Conclusions:
- The flavin-tryptophan dyad (F10T) effectively models the quantum spin mechanisms underlying cryptochrome-based magnetoreception.
- These findings provide crucial insights into how avian navigation might function at Earth's magnetic field.
- The study advances our understanding of the biophysical basis of magnetoreception.
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