Ruban A V, Pesaresi P, Wacker U, Irrgang K D, Bassi R, Horton P
Robert Hill Institute for Photosynthesis Research, Department of Molecular Biology & Biotechnology, University of Sheffield, UK.
Biochemistry. 1998 Aug 18;37(33):11586-91. doi: 10.1021/bi9809369.
The relationship between the binding of dicyclohexylcarbodiimide (DCCD) to isolated light-harvesting proteins of photosystem II and the inhibition of chlorophyll fluorescence quenching by DCCD have been investigated. For a range of different complexes an approximately linear relationship was obtained between the efficiency of DCCD binding and the DCCD-dependent reversal of fluorescence quenching. The most efficient labeling was found for the minor light-harvesting complexes, CP29 and CP26. In the case of the former, five different preparations were compared including two reconstituted complexes in which a putative DCCD-binding site had been mutagenized. Again, an approximately linear relationship between DCCD binding and the extent of reversal of fluorescence quenching was found. However, the binding of DCCD was found to occur at least an order of magnitude faster than the change in fluorescence. The results are discussed in terms of the multiplicity of DCCD-binding sites and the influence of protein structure on both the binding of DCCD and the fluorescence quenching mechanism.
已对二环己基碳二亚胺（DCCD）与分离的光系统II捕光蛋白的结合以及DCCD对叶绿素荧光猝灭的抑制作用之间的关系进行了研究。对于一系列不同的复合物，在DCCD结合效率与DCCD依赖性荧光猝灭逆转之间获得了近似线性关系。发现对次要捕光复合物CP29和CP26的标记效率最高。对于前者，比较了五种不同的制剂，包括两种重构复合物，其中一个假定的DCCD结合位点已被诱变。同样，在DCCD结合与荧光猝灭逆转程度之间发现了近似线性关系。然而，发现DCCD的结合发生速度比荧光变化至少快一个数量级。根据DCCD结合位点的多样性以及蛋白质结构对DCCD结合和荧光猝灭机制的影响对结果进行了讨论。
