THE 3-DIMENSIONAL STRUCTURE OF AN ARACHIDONIC-ACID 15-LIPOXYGENASE
THE 3-DIMENSIONAL STRUCTURE OF AN ARACHIDONIC-ACID 15-LIPOXYGENASE
复制标题
DOI：
10.1126/science.8502991
复制
发表时间：
1993-06-04
期刊：
影响因子：
56.9
通讯作者：
AMZEL, LM
中科院分区：
文献类型：
--
作者：
BOYINGTON, JC;GAFFNEY, BJ;AMZEL, LM
在哺乳动物中，脂氧合酶对蛛网膜化的氢过氧化剂导致白细胞和脂毒素的形成，可介导炎症反应的化合物。脂氧酶是含有非血红素铁并存在于许多动物细胞中的双加氧酶。大豆脂氧酶-1是一种与哺乳动物脂氧酶密切相关的单链，839个残留蛋白。大豆脂氧酶-1的结构求解为2.6埃斯特罗姆分辨率，表明该酶具有两个结构域：146个残留的β枪管和693个沉积物螺旋束。铁原子位于较大域的中心，并由三个组氨酸和羧基末端的库协调。配位几何形状不规则，似乎是扭曲的八面体，其中两个相邻位置不被配体占据。在弯曲的圆柱体的形状和圆锥形的形状中，两个空腔连接到酶的表面上，铁有两个相邻和未占用位置的铁，可以与底物的1 4-二烯系统相互作用，并与子材料的1 4-二烯系统相互作用。催化过程中的分子氧。
In mammals, the hydroperoxidation of arachidonic acid by lipoxygenases leads to the formation of leukotrienes and lipoxins, compounds that mediate inflammatory responses. Lipoxygenases are dioxygenases that contain a nonheme iron and are present in many animal cells. Soybean lipoxygenase-1 is a single-chain, 839-residue protein closely related to mammalian lipoxygenases. The structure of soybean lipoxygenase-1 solved to 2.6 angstrom resolution shows that the enzyme has two domains: a 146-residue beta barrel and a 693-residue helical bundle. The iron atom is in the center of the larger domain and is coordinated by three histidines and the COO- of the carboxyl terminus. The coordination geometry is nonregular and appears to be a distorted octahedron in which two adjacent positions are not occupied by ligands. Two cavities, in the shapes of a bent cylinder and a frustum, connect the unoccupied positions to the surface of the enzyme The iron, with two adjacent and unoccupied positions, is poised to interact with the 1 4-diene system of the substrate and with molecular oxygen during catalysis.