Instituto de Química Física "Rocasolano", Consejo Superior de Investigaciones Científicas, 28006, Madrid, Spain.
Departamento de Genética y Microbiología, Área de Genética (Unidad Asociada al Instituto de Química Física "Rocasolano", CSIC), Facultad de Biología, Universidad de Murcia, Murcia, 30100, Spain.
Curr Opin Struct Biol. 2019 Aug;57:47-55. doi: 10.1016/j.sbi.2019.01.020. Epub 2019 Mar 7.
Vitamin B-based photoreceptor proteins sense ultraviolet (UV), blue or green light using 5'-deoxyadenosylcobalamin (AdoCbl). The prototype of this widespread bacterial photoreceptor family, CarH, controls light-dependent gene expression in photoprotective cellular responses. It represses transcription in the dark by binding to operator DNA as an AdoCbl-bound tetramer, whose disruption by light relieves operator binding to allow transcription. Structures of the 'dark' (free and DNA-bound) and 'light' CarH states and studies on the unusual AdoCbl photochemistry have provided fundamental insights into these photoreceptors. We highlight these, the plasticity within a conserved mode of action among CarH homologs, their distribution, and their promising applications in optogenetics and synthetic biology.
基于维生素 B 的感光蛋白利用 5'-脱氧腺苷钴胺素（AdoCbl）感应紫外线 (UV)、蓝光或绿光。这个广泛存在于细菌感光蛋白家族中的原型 CarH 控制着光依赖性基因表达在光保护细胞反应中。它通过与 DNA 结合作为 AdoCbl 结合的四聚体结合到操纵子 DNA 上，在黑暗中抑制转录，而光的破坏则减轻了操纵子的结合，从而允许转录。'黑暗'（游离和 DNA 结合）和'光'CarH 状态的结构以及对不寻常的 AdoCbl 光化学的研究为这些感光蛋白提供了基本的见解。我们强调了这些，在 CarH 同源物中保守作用模式内的可塑性，它们的分布，以及它们在光遗传学和合成生物学中的有前途的应用。
