紫外线共振拉曼光谱证据表明章鱼视紫红质中不存在酪氨酸盐以及色氨酸残基在向酸性视紫红质转变过程中的参与情况。

Ultraviolet resonance Raman evidence for the absence of tyrosinate in octopus rhodopsin and the participation of Trp residues in the transition to acid metarhodopsin.

作者信息

Hashimoto S, Takeuchi H, Nakagawa M, Tsuda M

机构信息

Pharmaceutical Institute, Tohoku University, Aobayama, Japan.

出版信息

FEBS Lett. 1996 Dec 2;398(2-3):239-42. doi: 10.1016/s0014-5793(96)01250-1.

DOI:10.1016/s0014-5793(96)01250-1

PMID:8977115

Abstract

The ultraviolet (244 nm) resonance Raman spectra of octopus rhodopsin and its photoproduct, acid metarhodopsin, do not give any evidence for a tyrosinate. This finding excludes the possibility that Tyr-112 serves as the counter anion to the protonated Schiff base as does Glu-113 in bovine rhodopsin. Upon photoconversion from rhodopsin to acid metarhodopsin, Trp and Tyr Raman bands decrease in intensity and concomitantly a Trp band shifts in frequency. The changes of Trp Raman bands are ascribed to changes in hydrophobic interactions and conformation, suggesting a possible role of Trp in the photoconversion process of octopus rhodopsin.

摘要

章鱼视紫红质及其光产物酸性视紫红质的紫外（244纳米）共振拉曼光谱未提供任何酪氨酸根离子的证据。这一发现排除了在牛视紫红质中起到质子化席夫碱抗衡阴离子作用的是112位酪氨酸，如同113位谷氨酸那样的可能性。在视紫红质向酸性视紫红质的光转化过程中，色氨酸和酪氨酸的拉曼谱带强度降低，同时一个色氨酸谱带发生频率位移。色氨酸拉曼谱带的变化归因于疏水相互作用和构象的改变，这表明色氨酸在章鱼视紫红质的光转化过程中可能发挥作用。