ACCEPTOR SPECIFICITY OF FLAVINS AND FLAVOPROTEINS .1. TECHNIQUES FOR ANAEROBIC SPECTROPHOTOMETRY
ACCEPTOR SPECIFICITY OF FLAVINS AND FLAVOPROTEINS .1. TECHNIQUES FOR ANAEROBIC SPECTROPHOTOMETRY
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DOI：
10.1016/0005-2728(71)90092-2
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发表时间：
1971-01-01
期刊：
影响因子：
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通讯作者：
DIXON, M
中科院分区：
文献类型：
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作者：
DIXON, M
1.本文介绍了一种结构简单的在严格厌氧条件下进行分光光度测定的装置，它不需要特殊的比色皿。它允许连续添加几种试剂，而无需将系统向空气开放。2.连二亚硫酸盐的吸收光谱在314 nm处有一强吸收峰，并测定了其摩尔吸光度。这为用连二亚硫酸盐滴定受体提供了一种简便的方法.一个分子的连二亚硫酸盐在溶液中与一个分子的O2反应非常迅速。O2被定量还原为H2O2。当连二亚硫酸盐过量时，另一个慢得多的反应随之发生，其中第二个连二亚硫酸盐分子被过氧化物氧化。本文研究了连二亚硫酸盐对黄素蛋白研究中常用的各种受体的还原作用。大多数反应非常迅速，但少数是减少相对缓慢或根本没有。5.大多数受体不与连二亚硫酸盐的氧化产物亚硫酸盐发生显着反应。一分子连二亚硫酸盐提供两个还原当量。然而，一些受体与形成的亚硫酸盐反应，产生涉及两个以上当量的第二反应。
1. Easily constructed apparatus is described for spectrophotometry under strictly anaerobic conditions without requiring special cuvettes. It permits the addition of several reagents successively without opening the system to the air.2. The absorption spectrum of dithionite shows a strong peak at 314 nm, the molar absorbance of which has been determined. This gives a convenient method for the titration of acceptors with dithionite.3. One molecule of dithionite reacts very rapidly with one molecule of O2in solution. The O2is reduced quantitatively to H2O2. With excess of dithionite another, much slower, reaction follows, in which a second molecule of dithionite is oxidized by the peroxide.4. A study has been made of the reduction by dithionite of a variety of acceptors commonly used in the study of flavoproteins. The majority react very rapidly, but a few are reduced relatively slowly or not at all.5. The majority of acceptors do not react significantly with sulphite, the oxidation product of dithionite. One molecule of dithionite then provides two reduction equivalents. A few acceptors, however, react with the sulphite formed, giving a second reaction involving two more equivalents.