Human brain neuroglobin structure reveals a distinct mode of controlling oxygen affinity
Human brain neuroglobin structure reveals a distinct mode of controlling oxygen affinity
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DOI：
10.1016/s0969-2126(03)00166-7
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发表时间：
2003-09-01
期刊：
影响因子：
5.7
通讯作者：
Bolognesi, M
中科院分区：
文献类型：
--
作者：
Pesce, A;Dewilde, S;Bolognesi, M
神经珠蛋白是最近发现的珠蛋白超家族成员，主要表达于脊椎动物的大脑和视网膜。增加O-2供应，神经红蛋白促进缺氧损伤时神经元的存活，可能限制脑损伤。在缺乏外源性配体的情况下，神经红蛋白表现为六配位血红素。O-2和CO与血红素铁结合，取代内源性HisE7血红素远端配体。六配位的人类神经红蛋白显示出适合宿主可逆双组氨酸血红素复合物的经典红蛋白折叠和延长的蛋白质基质腔，以促进O-2向血红素的扩散。神经红蛋白的结构表明，经典的红蛋白折叠具有惊人的适应性，这表明血红蛋白和肌红蛋白只是一个广泛而功能多样化的蛋白质同源超家族中的两个例子。
Neuroglobin, mainly expressed in vertebrate brain and retina, is a recently identified member of the globin superfamily. Augmenting O-2 supply, neuroglobin promotes survival of neurons upon hypoxic injury, potentially limiting brain damage. In the absence of exogenous ligands, neuroglobin displays a hexacoordinated heme. O-2 and CO bind to the heme iron, displacing the endogenous HisE7 heme distal ligand. Hexacoordinated human neuroglobin displays a classical globin fold adapted to host the reversible bis-histidyl heme complex and an elongated protein matrix cavity, held to facilitate O-2 diffusion to the heme. The neuroglobin structure suggests that the classical globin fold is endowed with striking adaptability, indicating that hemoglobin and myoglobin are just two examples within a wide and functionally diversified protein homology superfamily.