Kim J I, Ohtake A, Sato K
Mitsubishi Kasei Institute of Life Sciences, Machida-shi, Tokyo, Japan.
Biochem Biophys Res Commun. 1997 Jan 3;230(1):133-5. doi: 10.1006/bbrc.1996.5900.
The circular dichroism (CD) spectrum of omega-conotoxin GVIA is quite different from those of omega-conotoxin MVIIA and MVIIC, despite their distinct similarity in three dimensional structures. In order to characterize the unique CD spectrum of omega-conotoxin GVIA, we focused our attention on the aromatic chromophore and analyzed the CD spectra of three synthetic analogs, in which Tyr13, Tyr22, and Tyr27 were individually replaced by alanine. Replacement of Tyr27 caused a significant change in both the near- and far-ultraviolet CD spectrum of omega-conotoxin GVIA and resulted in the omega-conotoxin MVIIA/MVIIC-like pattern, suggesting that Tyr27 has a dominant contribution to the unique CD profile of omega-conotoxin GVIA.
尽管ω-芋螺毒素GVIA、MVIIA和MVIIC在三维结构上有明显的相似性，但它们的圆二色性（CD）光谱却大不相同。为了表征ω-芋螺毒素GVIA独特的CD光谱，我们将注意力集中在芳香发色团上，并分析了三种合成类似物的CD光谱，其中酪氨酸13、酪氨酸22和酪氨酸27分别被丙氨酸取代。酪氨酸27的取代导致ω-芋螺毒素GVIA的近紫外和远紫外CD光谱都发生了显著变化，并产生了类似ω-芋螺毒素MVIIA/MVIIC的模式，这表明酪氨酸27对ω-芋螺毒素GVIA独特的CD谱有主要贡献。
