8DDY

Helical rods of far-red light-absorbing allophycocyanin in Synechococcus sp.

8DDY の概要

• エントリーDOI: 10.2210/pdb8ddy/pdb
• EMDBエントリー: 27382
• 分子名称: Allophycocyanin subunit alpha, Allophycocyanin subunit beta, PHYCOCYANOBILIN, ... (5 entities in total)
• 機能のキーワード: allophycocyanin, phycobiliprotein, photosystem, photosynthesis, energy transfer, cyanobacteria, far-red light, farlip, lolip
• 由来する生物種: Synechococcus sp. 63AY4M1; 詳細
• タンパク質・核酸の鎖数: 6
• 化学式量合計: 118354.99

構造登録者

Gisriel, C.J.,Shen, G.S.,Soulier, N.T.,Flesher, D.A.,Brudvig, G.W.,Bryant, D.A. (登録日: 2022-06-19, 公開日: 2023-04-05)

主引用文献

Gisriel, C.J.,Elias, E.,Shen, G.,Soulier, N.T.,Flesher, D.A.,Gunner, M.R.,Brudvig, G.W.,Croce, R.,Bryant, D.A.
Helical allophycocyanin nanotubes absorb far-red light in a thermophilic cyanobacterium.
Sci Adv, 9:eadg0251-eadg0251, 2023

PubMed Abstract: To compete in certain low-light environments, some cyanobacteria express a paralog of the light-harvesting phycobiliprotein, allophycocyanin (AP), that strongly absorbs far-red light (FRL). Using cryo-electron microscopy and time-resolved absorption spectroscopy, we reveal the structure-function relationship of this FRL-absorbing AP complex (FRL-AP) that is expressed during acclimation to low light and that likely associates with chlorophyll a-containing photosystem I. FRL-AP assembles as helical nanotubes rather than typical toroids due to alterations of the domain geometry within each subunit. Spectroscopic characterization suggests that FRL-AP nanotubes are somewhat inefficient antenna; however, the enhanced ability to harvest FRL when visible light is severely attenuated represents a beneficial trade-off. The results expand the known diversity of light-harvesting proteins in nature and exemplify how biological plasticity is achieved by balancing resource accessibility with efficiency.

PubMed: 36961897
DOI: 10.1126/sciadv.adg0251

実験手法

ELECTRON MICROSCOPY (2.89 Å)