Chang Chia-Hao, Gómez Sandra, Fontaine Danielle M, Fikas Panagiotis, Branchini Bruce R, Anderson James C
Department of Chemistry, University College London, 20 Gordon Street, London, WC1H 0AJ, UK.
Departamento de Quimica Fisica, University of Salamanca, 37008, Spain.
Org Biomol Chem. 2023 Apr 5;21(14):2941-2949. doi: 10.1039/d3ob00247k.
A new rationally designed fully rotationally restricted luciferin has been synthesised. This synthetic luciferin, based upon the structure of infraluciferin, has two intramolecular H-bonds to reduce degrees of freedom, an amine group to enhance ICT process, and an alkenyl group to increase π-conjugation. In the spectroscopic measurements and computational calculations, enamine luciferin showed more red-shifted absorption and fluorescence emission than LH and iLH. With PpyWT luciferase enamine luciferin gave bioluminescence at 564 nm which is similar to LH at 561 nm. Further investigation by docking studies revealed that the emission wavelength of enamine luciferin might be attributed to the unwanted twisted structure caused by Asp531 within the enzyme. With mutant luciferase FlucRed, the major emission peak was shifted to 606 nm, a distinct shoulder above 700 nm, and 21% of its spectrum located in the nIR range.
一种新的经过合理设计的完全旋转受限的荧光素已被合成。这种基于亚荧光素结构的合成荧光素具有两个分子内氢键以减少自由度、一个胺基以增强ICT过程以及一个烯基以增加π共轭。在光谱测量和计算计算中，烯胺荧光素显示出比LH和iLH更多的红移吸收和荧光发射。对于PpyWT荧光素酶，烯胺荧光素在564nm处产生生物发光，这与在561nm处的LH相似。通过对接研究的进一步调查表明，烯胺荧光素的发射波长可能归因于酶内Asp531引起的不必要的扭曲结构。对于突变荧光素酶FlucRed，主要发射峰移至606nm，在700nm以上有明显的肩峰，其光谱的21%位于近红外范围内。
