Verboven Christel, Rabijns Anja, De Maeyer Marc, Van Baelen Hugo, Bouillon Roger, De Ranter Camiel
Laboratorium voor Analytische Chemie en Medicinale Fysicochemie, Faculteit Farmaceutische Wetenschappen, Katholieke Universiteit Leuven, E. Van Evenstraat 4, B-3000 Leuven, Belgium.
Nat Struct Biol. 2002 Feb;9(2):131-6. doi: 10.1038/nsb754.
The human serum vitamin D-binding protein (DBP) has many physiologically important functions, ranging from transporting vitamin D3 metabolites, binding and sequestering globular actin and binding fatty acids to functioning in the immune system. Here we report the 2.3 A crystal structure of DBP in complex with 25-hydroxyvitamin D3, a vitamin D3 metabolite, which reveals the vitamin D-binding site in the N-terminal part of domain I. To more explicitly explore this, we also studied the structure of DBP in complex with a vitamin D3 analog. Comparisons with the structure of human serum albumin, another family member, reveal a similar topology but also significant differences in overall, as well as local, folding. These observed structural differences explain the unique vitamin D3-binding property of DBP.
人血清维生素D结合蛋白（DBP）具有许多重要的生理功能，从转运维生素D3代谢物、结合并隔离球状肌动蛋白、结合脂肪酸到在免疫系统中发挥作用。在此，我们报告了DBP与维生素D3代谢物25-羟基维生素D3复合物的2.3埃晶体结构，该结构揭示了结构域I N端部分的维生素D结合位点。为了更深入地探究这一点，我们还研究了DBP与一种维生素D3类似物复合物的结构。与另一个家族成员人血清白蛋白的结构比较显示，它们具有相似的拓扑结构，但在整体以及局部折叠方面也存在显著差异。这些观察到的结构差异解释了DBP独特的维生素D3结合特性。
