Luck Meike, Bruun Sara, Keidel Anke, Hegemann Peter, Hildebrandt Peter
Humboldt Universität zu Berlin, Institut für Biologie, Experimentelle Biophysik, Invalidenstr. 42, D-10115 Berlin, Germany.
Technische Universität Berlin, Institut für Chemie, Sekr. PC14, Straße des 17. Juni 135, D-10623 Berlin, Germany.
FEBS Lett. 2015 Apr 28;589(10):1067-71. doi: 10.1016/j.febslet.2015.03.024. Epub 2015 Mar 31.
Histidine kinase rhodopsin 1 is a photoreceptor in green algae functioning as a UV-light sensor. It switches between a UV-absorbing state (Rh-UV) and a blue-absorbing state (Rh-Bl) with a protonated retinal Schiff base (RSB) cofactor in a mixture of 13-trans,15-anti and 13-cis,15-syn isomers. The present spectroscopic study now shows that cofactor-protein assembly stabilizes the protonated 13-trans,15-anti RSB isomer. Formation of the active photoswitch requires the photoinduced conversion to Rh-UV. The transitions between the Rh-Bl isomers and the deprotonated 13-cis,15-anti and 13-trans,15-syn isomers of Rh-UV proceed via multiple photoisomerizations of one or simultaneously two double bonds.
组氨酸激酶视紫红质1是绿藻中的一种光感受器，作为紫外线传感器发挥作用。它在13-反式、15-反式和顺式、15-顺式异构体混合物中，与质子化视黄醛席夫碱（RSB）辅因子一起，在吸收紫外线状态（Rh-UV）和吸收蓝光状态（Rh-Bl）之间切换。目前的光谱研究表明，辅因子-蛋白质组装稳定了质子化的13-反式、15-反式RSB异构体。活性光开关的形成需要光诱导转化为Rh-UV。Rh-Bl异构体与Rh-UV的去质子化13-顺式、15-反式和13-反式、15-顺式异构体之间的转变是通过一个或同时两个双键的多次光异构化进行的。
