Engineering the photoactive orange carotenoid protein with redox-controllable structural dynamics and photoprotective function.
Engineering the photoactive orange carotenoid protein with redox-controllable structural dynamics and photoprotective function.
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工程设计具有氧化还原可控结构动力学和光保护功能的光活性橙色类胡萝卜素蛋白
DOI：
10.1016/j.bbabio.2020.148174
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发表时间：
2020
期刊：
影响因子：
--
通讯作者：
Sluchanko
中科院分区：
文献类型：
--
作者：
Slonimskiy;Maksimov;Lukashev;Moldenhauer;Friedrich;Sluchanko
光合作用需要各种光保护机制才能使生物体在强光下生存。在蓝藻中，在强光下，橙色类胡萝卜素蛋白(OCP)可逆地从橙色(OCPO)光切换到红色(OCPR)形式，后者与天线(藻胆体，PBS)结合并抑制其过度激发。OCPR积聚意味着紧凑的暗适应OCPO状态的重组，包括N端延伸(NTE)的分离和蛋白质结构域的分离，这一过程可通过与荧光恢复蛋白(FRP)的相互作用而逆转。OCP的光转化被认为是通过一种中间体发生的，其特征是具有类似OCPR的吸收光谱和类似OCPO的蛋白质结构，但步骤的层次仍然存在争议。在这里，我们设计并分析了一种OCP变体，其NTE通过工程二硫键(OCPCC)捕获在C-末端结构域(CTD)上。NTE捕获保留了紧凑蛋白质结构中的OCP光循环，但排除了与PBS，特别是FRP的功能相互作用，后者在二硫键减少后完全恢复。FRP不与暗适应的氧化OCPCC相互作用，与还原的OCPCC结合的效率几乎与OCPO一样高，没有NTE，这表明低亲和力的FRP与OCPO的结合是通过NTE置换实现的。PbS与氧化后的OCPCC之间的激发能量传递效率较低，表明OCPCC与PbS的结合方向不利于PbS荧光的猝灭。我们的方法支持OCP光循环中OCPR样中间体的存在，并显示了光谱变化与功能OCP光激活的有效解耦，从而能够对其结构动力学和功能进行氧化还原控制。
Photosynthesis requires various photoprotective mechanisms for survival of organisms in high light. In cyanobacteria exposed to high light, the Orange Carotenoid Protein (OCP) is reversibly photoswitched from the orange (OCPO) to the red (OCPR) form, the latter binds to the antenna (phycobilisomes, PBs) and quenches its overexcitation. OCPRaccumulation implicates restructuring of a compact dark-adapted OCPOstate including detachment of the N-terminal extension (NTE) and separation of protein domains, which is reversed by interaction with the Fluorescence Recovery Protein (FRP). OCP phototransformation supposedly occurs via an intermediate characterized by an OCPR-like absorption spectrum and an OCPO-like protein structure, but the hierarchy of steps remains debatable. Here, we devise and analyze an OCP variant with the NTE trapped on the C-terminal domain (CTD) via an engineered disulfide bridge (OCPCC). NTE trapping preserves OCP photocycling within the compact protein structure but precludes functional interaction with PBs and especially FRP, which is completely restored upon reduction of the disulfide bridge. Non-interacting with the dark-adapted oxidized OCPCC, FRP binds reduced OCPCCnearly as efficiently as OCPOdevoid of the NTE, suggesting that the low-affinity FRP binding to OCPOis realized via NTE displacement. The low efficiency of excitation energy transfer in complexes between PBs and oxidized OCPCCindicates that OCPCCbinds to PBs in an orientation suboptimal for quenching PBs fluorescence. Our approach supports the presence of the OCPR-like intermediate in the OCP photocycle and shows effective uncoupling of spectral changes from functional OCP photoactivation, enabling redox control of its structural dynamics and function.
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影响因子：
2.9
作者：
Lu Y;Liu H;Saer R;Li VL;Zhang H;Shi L;Goodson C;Gross ML;Blankenship RE
通讯作者：
Blankenship RE
蓝藻非光化学猝灭的位点、触发因素、猝灭机制和恢复：最新更新
影响因子：
3.7
作者：
R. Sonani;A. Gardiner;R. P. Rastogi;R. Cogdell;B. Robert;D. Madamwar
通讯作者：
D. Madamwar
不同蓝藻低同源性 FRP 与集胞藻 OCP 的功能相互作用
DOI：
10.1101/247882
发表时间：
2018
期刊：
bioRxiv
影响因子：
--
作者：
Y. B. Slonimskiy;E. Maksimov;E. Lukashev;M. Moldenhauer;C. Jeffries;D. Svergun;T. Friedrich;N. Sluchanko
通讯作者：
N. Sluchanko
影响因子：
15
作者：
Konold, Patrick E.;van Stokkum, Ivo H. M.;Kennis, John T. M.
通讯作者：
Kennis, John T. M.
影响因子：
4.3
作者：
Gwizdala, Michal;Wilson, Adjele;Kirilovsky, Diana
通讯作者：
Kirilovsky, Diana