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Updated: Feb 28, 2026

Purification and Reconstitution of TRPV1 for Spectroscopic Analysis
Published on: July 3, 2018
Determination of Radical-Radical Distances in Light-Active Proteins and Their Implication for Biological
Daniel Nohr1, Bernd Paulus1, Ryan Rodriguez1
1Institute of Physical Chemistry, Albert-Ludwigs-Universität Freiburg, Albertstrasse 21, 79104, Freiburg, Germany.
Abstract:
Light-generated short-lived radial pairs have been suggested to play pivotal roles in cryptochromes and photolyases. Cryptochromes are very probably involved in magnetic compass sensing in migratory birds and the magnetic-field-dependent behavior of insects. We examined photo-generated transient states in the cryptochrome of Drosophila melanogaster and in the structurally related DNA-repair enzyme Escherichia coli DNA photolyase. Using pulsed EPR spectroscopy, the exchange and dipolar contributions to the electron spin-spin interaction were determined in a straightforward and direct way. With these parameters, radical-pair partners may be identified and the magnetoreceptor efficiency of cryptochromes can be evaluated. We present compelling evidence for an extended electron-transfer cascade in the Drosophila cryptochrome, and identified W394 as a key residue for flavin photoreduction and formation of a spin-correlated radical pair with a sufficient lifetime for high-sensitivity magnetic-field sensing.
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