Effects of Dynamical Degrees of Freedom on Magnetic Compass Sensitivity: A Comparison of Plant and Avian Cryptochromes

• DOI: 10.1021/jacs.2c06233
• Publication Date: 2022-12-02T20:18:08Z
• Authors: Gesa Grüning; Siu Ying Wong; Luca Gerhards; Fabian Schuhmann; Daniel R. Kattnig; P. J. Hore; Ilia A. Solov’yov
• Keywords: Compass

The magnetic compass of migratory birds is thought to rely on a radical pair reaction inside the blue-light photoreceptor protein cryptochrome. sensitivity such sensor weak external fields determined by variety interactions, including electron-nuclear hyperfine interactions. Here, we investigate implications thermal motion, focusing fluctuations in dihedral and librational angles flavin adenine dinucleotide (FAD) tryptophan (Trp) radicals cryptochrome 4a from European robin (Erithacus rubecula, ErCry4a) pigeon (Columba livia, ClCry4a) 1 plant Arabidopsis thaliana (AtCry1). Molecular dynamics simulations density functional theory-derived interactions are used calculate quantum yield recombination dependent direction geomagnetic field. This quantity various dynamical parameters compared for [FAD•- Trp•+] ErCry4a, ClCry4a, AtCry1, with TrpC or TrpD being third fourth components triad/tetrad respective proteins. We find that (i) differences average pairs small, (ii) motions TrpC•+ avian cryptochromes appreciably smaller than (iii) rapid vibrational leading strong couplings affect spin depending usage instantaneous time-averaged Future investigations should therefore not be based single snapshots structure but include ensemble properties