8K9O
Crystal structure of Cyanobacteriochrome RcaE GAF domain in Pg state
Summary for 8K9O
| Entry DOI | 10.2210/pdb8k9o/pdb |
| Descriptor | histidine kinase, PHYCOCYANOBILIN (3 entities in total) |
| Functional Keywords | cyanobacteriochrome, chromatic acclimation, signaling protein |
| Biological source | Microchaete diplosiphon |
| Total number of polymer chains | 1 |
| Total formula weight | 22633.80 |
| Authors | Nagae, T.,Hirose, Y.,Mishima, M. (deposition date: 2023-08-01, release date: 2024-05-15, Last modification date: 2024-11-13) |
| Primary citation | 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 Cited by 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: 38865454DOI: 10.1126/sciadv.adn8386 PDB entries with the same primary citation |
| Experimental method | X-RAY DIFFRACTION (1.75 Å) |
Structure validation
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