Light-induced structural changes in a full-length cyanobacterial phytochrome probed by time-resolved X-ray scattering

Communications Biology

Martin N. Pedersen¹  Michael Wulff¹  Joyce Woodhouse²  Giorgio Schirò²  Martin Weik²  Eugenio De La Mora²  Nigel S. Scrutton³  Samantha J. O. Hardman³  Derren J. Heyes³  Marco Cammarata⁴ 

[1] European Synchrotron Radiation Facility, Grenoble, France;Institut de Biologie Structurale, CNRS, Univ. Grenoble Alpes, CEA, Grenoble, France;Manchester Institute of Biotechnology, University of Manchester, Manchester, UK;Univ. Rennes 1, CNRS, UBL, Institut de Physique de Rennes (IPR) - UMR 6251, Rennes, France

DOI  :  10.1038/s42003-018-0242-0

学科分类：生物科学（综合）

来源: Nature Publishing Group

【 摘 要 】

Phytochromes are photoreceptor proteins that transmit a light signal from a photosensory region to an output domain. Photoconversion involves protein conformational changes whose nature is not fully understood. Here, we use time-resolved X-ray scattering and optical spectroscopy to study the kinetics of structural changes in a full-length cyanobacterial phytochrome and in a truncated form with no output domain. X-ray and spectroscopic signals on the µs/ms timescale are largely independent of the presence of the output domain. On longer time-scales, large differences between the full-length and truncated proteins indicate the timeframe during which the structural transition is transmitted from the photosensory region to the output domain and represent a large quaternary motion. The suggested independence of the photosensory-region dynamics on the µs/ms timescale defines a time window in which the photoreaction can be characterized (e.g. for optogenetic design) independently of the nature of the engineered output domain.

【 授权许可】

CC BY