The primary structural photoresponse of phytochrome proteins captured by a femtosecond X-ray laser

Elin Claesson, Weixiao Yuan Wahlgren, Heikki Takala, Suraj Pandey, Leticia Castillon, Valentyna Kuznetsova, L ́eocadie Henry, Melissa Carrillo, Matthijs Panman, Joachim Kübel, Rahul Nanekar, Linnea Isaksson, Amke Nimmrich, Andrea Cellini, Dmitry Morozov, Michał Maj, Moona Kurttila, Robert Bosman, Eriko Nango, Rie TanakaTomoyuki Tanaka, Luo Fangjia, So Iwata, Shigeki Owada, Keith Moffat, Gerrit Groenhof, Emina A. Stojkovic, Janne A. Ihalainen, Marius Schmidt, Sebastian Westenhoff

Forskningsoutput: TidskriftsbidragArtikelVetenskaplig

Sammanfattning

Phytochrome proteins control the growth, reproduction, and photosynthesis of plants, fungi, and bacteria. Light is detected by a bilin cofactor, but it remains elusive how this leads to activation of the protein through structural changes. We present serial femtosecond X-ray crystallographic data of the chromophore-binding domains of a bacterial phytochrome at delay times of 1 ps and 10 ps after photoexcitation. The structures reveal a twist of the D-ring, which lead to partial detachment of the chromophore from the protein. Unexpectedly, the conserved so-called pyrrole water is photodissociated from the chromophore, concomitant with movement of the A-ring and a key signalling aspartate. The changes are wired together by ultrafast backbone and water movements around the chromophore, channeling them into signal transduction towards the output domains. We suggest that the water dissociation is key to the phytochrome photoresponse, explaining the earliest steps of how plants, fungi and bacteria sense red light.
Bidragets titel på inmatningsspråkFytokromiproteiinien ensimmäiset rakennemuutokset mitattu Röntgen-laserilla
Originalspråkengelska
TidskriftBioRxiv beta : the preprint server for biology
VolymOctober 01, 2019
DOI
StatusPublicerad - 1 okt 2019
MoE-publikationstypB1 Artikel i en vetenskaplig tidskrift

Citera det här