单体和纤维状溶菌酶的低频光谱分析。

Low-frequency spectroscopic analysis of monomeric and fibrillar lysozyme.

机构信息

Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane, QLD 4072, Australia.

出版信息

Appl Spectrosc. 2011 Mar;65(3):260-4. doi: 10.1366/10-06162.

DOI:10.1366/10-06162

PMID:21352645

Abstract

Terahertz time-domain spectroscopy (THz-TDS) and Fourier transform infrared (FT-IR) spectroscopy were used to generate far-infrared and low-frequency spectral measurements of monomeric lysozyme and lysozyme fibrils. The formation of lysozyme fibrils was verified by the Thioflavin T assay and transmission electron microscopy (TEM). It was evident in the FT-IR spectra that between 150 and 350 cm(-1) the two spectra diverge, with the lysozyme fibrils showing higher absorbance intensity than the monomeric form. The broad absorption phenomenon is likely due to light scattered from the fibrillar architecture of lysozyme fibrils as supported by simulation of Rayleigh light scattering. The lack of discrete phonon-like peaks suggest that far-infrared spectroscopy cannot detect vibrational modes between the highly ordered hydrogen-bonded beta-pleated sheets of the lysozyme subunit.

摘要

太赫兹时域光谱（THz-TDS）和傅里叶变换红外（FT-IR）光谱被用于生成单体溶菌酶和溶菌酶原纤维的远红外和低频光谱测量。溶菌酶原纤维的形成通过噻唑蓝（Thioflavin T）检测和透射电子显微镜（TEM）得到了验证。在 FT-IR 光谱中，在 150 到 350 厘米（-1）之间，两个光谱出现了分歧，溶菌酶原纤维的吸收强度比单体形式更高。这种宽吸收现象可能是由于来自溶菌酶原纤维的纤维状结构的光散射所致，这得到了瑞利光散射模拟的支持。离散的声子样峰的缺乏表明，远红外光谱不能检测到溶菌酶亚基高度有序的氢键β-折叠片之间的振动模式。