Experimental differential light-scattering correction to the circular dichroism of bacteriophage T2.
Experimental differential light-scattering correction to the circular dichroism of bacteriophage T2.
复制标题
对噬菌体 T2 圆二色性的实验差异光散射校正。
DOI：
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发表时间：
1973
影响因子：
11.1
通讯作者：
M. Maestre
中科院分区：
文献类型：
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作者：
B. Dorman;M. Maestre
提出了一种实验技术，可用于测定和校正生物宏观结构的圆二色光谱中的微分光散射效应。该分析是基于使用可变探测器几何形状，收集光在大的固体角度。破坏的T2病毒悬浮液和纯化的T2噬菌体DNA表现出与几何无关的光谱；完整T2病毒的光谱对检测几何高度敏感。根据光散射校正后得到的光谱，噬菌体颗粒中T2 DNA的结构为C型。我们得出结论：(i)测量的光散射样品的圆二色性可能对仪器的光探测几何高度敏感。这种效应表明左圆偏振光和右圆偏振光散射强度不同。（二）有些光学活性粒子虽然强烈散射光，但表现出与探测几何形状无关的圆二色性，因此显然不受微分光散射的影响。我们推断，是否产生微分光散射可能取决于在散射粒子的组织中是否存在有序不对称。（iii）任何光散射标本的圆二色性应在设计用于差分光散射校正的仪器中再次测量，作为有意义的结构结论的先决条件。（iv）圆二色性中的微分散射效应可能作为探测散射粒子的大阶组织的潜在有用方法。
Experimental techniques are presented that can be used to assay and correct for differential light scattering effects in circular dichroism spectra of biological macrostructures. The assay is based upon use of variable detector geometries that collect light over large solid angles. Disrupted T2 virus suspensions and purified T2 phage DNA exhibit geometry-independent spectra; the spectrum of intact T2 virus is highly sensitive to detection geometry. On the basis of spectra obtained after light-scattering correction, the structure of T2 DNA in the phage particle is assigned to the C form. We conclude that: (i) The measured circular dichroism of a light-scattering specimen may be highly sensitive to light-detection geometry of the instrument. This effect is indicative of differential scattering intensity for left and right circularly polarized light. (ii) Some optically active particles, although they scatter light intensely, exhibit circular dichroism that is independent of detection geometry and, therefore, apparently uninfluenced by differential light scattering. We infer that whether differential light scattering arises may depend upon the presence or absence of ordered asymmetry in the organization of the scattering particle. (iii) The circular dichroism of any light-scattering specimen should be measured again in apparatus designed for differential light-scattering correction as a prerequisite to meaningful structural conclusions. (iv) Differential scattering effects in circular dichroism may be potentially useful as a probe for large-order organization of the scattering particle.