X-ray absorption spectroscopy of bacterial sulfur globules.
X-ray absorption spectroscopy of bacterial sulfur globules.
复制标题
细菌硫球的 X 射线吸收光谱。
DOI：
10.1099/00221287-148-8-2267
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发表时间：
2002
期刊：
影响因子：
--
通讯作者：
Prince,RogerC
中科院分区：
文献类型：
--
作者：
George,GrahamN;Pickering,IngridJ;Yu,EileenY;Prince,RogerC
硫 K 边 X 射线吸收光谱是完整细胞和组织中硫生物化学的强大原位探针。在有利的情况下，该技术可以提供有关样品中存在的硫物质的化学特性的定量信息。 Prange 等人(8, 9) 最近报道了细菌硫存储球的 X 射线吸收光谱研究。不幸的是，我们认为所采用的实验技术存在重大问题，导致完全错误的结论。在最近的两篇论文中，Prange 等人(9) 采用了与我们使用的曲线拟合方法类似的曲线拟合方法（10 多年）(2,6,7)。本质上，该方法简单地将标准化合物的光谱与未知化合物 (2)（在本例中为细菌细胞培养物）的光谱进行线性组合拟合。这种类型的分析可以提供样品中各个硫类型的定量估计，但很大程度上取决于参考光谱的选择。 Prange 等人 (9) 推断出不同生物体球体中储存的硫的化学形式存在显着差异；他们得出结论，Beggiatoa alba 和 Thiomargarita namibiensis 的球体含有环八硫（S
Sulfur K-edge X-ray absorption spectroscopy is a powerful in situ probe of sulfur biochemistry in intact cells and tissues. Under favourable circumstances the technique can provide quantitative information on the chemical identity of the sulfur species that are present in a sample. Prange et al.(8, 9) have recently reported an X-ray absorption spectroscopic study of bacterial sulfur storage globules. Unfortunately there are substantial problems with the experimental technique employed that, we contend, lead to completely erroneous conclusions. In the more recent of their two papers Prange et al.(9) employed a curve-fitting method similar to that used by us (for more than 10 years)(2, 6, 7). In essence, the method employs simply fitting a linear combination of the spectra of standard compounds to that of the unknown (2), in this case cultures of bacterial cells. This type of analysis can provide quantitative estimates of the individual sulfur types in the sample, but is critically dependent upon the choice of reference spectra. Prange et al.(9) deduce substantial differences between the chemical forms of sulfur stored in the globules of different organisms; they conclude that the globules of Beggiatoa alba and Thiomargarita namibiensis contain cyclo-octasulfur (S