Department of Nuclear Engineering, School of Engineering, Tokai University, 4-1-1, Kitakaname, Hiratsuka-shi, Kanagawa, Japan.
J Xray Sci Technol. 2011;19(2):249-60. doi: 10.3233/XST-2011-0290.
XANES spectra of biomacromolecules such as histone, hemoglobin or bovine serum albumin (BSA) were measured in transmission at the S-K absorption edge for comparison with those of sulfur containing low-molecular weight biomolecules with special reference to the dependence on the chemical environment of sulfur. The spectra of dry histone and hemoglobin exhibited a prominent peak at the same energy as that of cysteine and glutathione (GSH), while the BSA spectrum showed an additional peak at a lower energy, which coincided with that of cystine and glutathione disulfide (GSSG). XANES peaks were found at the same energy even in a mammalian cell dry pellet. Spectra in the hydrated state exhibited similar profiles except for a very slight shift of resonance peaks to the lower energy. These results indicate that XANES profiles could be applicable to the mapping of S-C and S-S bonds in dry/hydrated biological systems using a spectromicroscopic technique. In addition, mass absorption coefficients of GSH and GSSG were determined.
XANES 光谱分析生物大分子，如组蛋白、血红蛋白或牛血清白蛋白（BSA），在 S-K 吸收边进行透射测量，以与含硫的低分子量生物分子的光谱进行比较，特别关注硫的化学环境依赖性。干燥的组蛋白和血红蛋白的光谱在与半胱氨酸和谷胱甘肽（GSH）相同的能量处表现出一个显著的峰，而 BSA 光谱在较低的能量处表现出一个额外的峰，与胱氨酸和谷胱甘肽二硫化物（GSSG）的峰相吻合。即使在哺乳动物细胞干燥的颗粒中，也能发现 XANES 峰在相同的能量处。水合状态下的光谱表现出相似的轮廓，除了共振峰略有向低能量移动。这些结果表明，XANES 图谱可以应用于使用光谱显微镜技术在干燥/水合生物系统中对 S-C 和 S-S 键进行映射。此外，还确定了 GSH 和 GSSG 的质量吸收系数。
