8K9O

Crystal structure of Cyanobacteriochrome RcaE GAF domain in Pg state

8K9O の概要

• エントリーDOI: 10.2210/pdb8k9o/pdb
• 分子名称: histidine kinase, PHYCOCYANOBILIN (3 entities in total)
• 機能のキーワード: cyanobacteriochrome, chromatic acclimation, signaling protein
• 由来する生物種: Microchaete diplosiphon
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 22633.80

構造登録者

Nagae, T.,Hirose, Y.,Mishima, M. (登録日: 2023-08-01, 公開日: 2024-05-15, 最終更新日: 2024-11-13)

主引用文献

Nagae, T.,Fujita, Y.,Tsuchida, T.,Kamo, T.,Seto, R.,Hamada, M.,Aoyama, H.,Sato-Tomita, A.,Fujisawa, T.,Eki, T.,Miyanoiri, Y.,Ito, Y.,Soeta, T.,Ukaji, Y.,Unno, M.,Mishima, M.,Hirose, Y.
Green/red light-sensing mechanism in the chromatic acclimation photosensor.
Sci Adv, 10:eadn8386-eadn8386, 2024

PubMed Abstract: Certain cyanobacteria alter their photosynthetic light absorption between green and red, a phenomenon called complementary chromatic acclimation. The acclimation is regulated by a cyanobacteriochrome-class photosensor that reversibly photoconverts between green-absorbing (Pg) and red-absorbing (Pr) states. Here, we elucidated the structural basis of the green/red photocycle. In the Pg state, the bilin chromophore adopted the extended C15-, structure within a hydrophobic pocket. Upon photoconversion to the Pr state, the bilin is isomerized to the cyclic C15-, structure, forming a water channel in the pocket. The solvation/desolvation of the bilin causes changes in the protonation state and the stability of π-conjugation at the B ring, leading to a large absorption shift. These results advance our understanding of the enormous spectral diversity of the phytochrome superfamily.

PubMed: 38865454
DOI: 10.1126/sciadv.adn8386

実験手法

X-RAY DIFFRACTION (1.75 Å)