Lankin V Z, Gordeeva N T, Tikhaze A K, Vikhert A M
Biokhimiia. 1985 Nov;50(11):1894-900.
In the presence of natural (liver mitochondria and microsomes) and artificial (liposomes from saturated phosphatidyl cholines) membranes, the rate of oxidation of an emulgated polyunsaturated fatty acid by reticulocyte lipoxygenase sharply increases and correlates with the amount of polyunsaturated fatty acid incorporated into the membrane. Hydrolysis of egg lecithine polyunsaturated acyls by phospholipase A2 drastically increases the rate of their enzymatic oxidation. It was shown that 15-hydroperoxyarachidonate is incorporated into lecithine liposomes at a much slower rate that the non-oxidized arachidonic acid. Solubilization of membranes with a detergent leads to the disappearance of the activating effect. Addition of saturated lecithine liposomes results in quenching of protein fluorescence of reticulocyte lipoxygenase, thus suggesting conformational changes in the enzyme structure upon its interaction with the membrane. The experimental results suggest that free polyunsaturated membraneous fatty acids are physiological substrates for animal lipoxygenases. One possible reason for the elevated rate of the lipoxygenase reaction in membranes is the alteration of enzyme conformation upon its interaction with the membrane matrix.
在天然（肝脏线粒体和微粒体）和人工（由饱和磷脂酰胆碱制成的脂质体）膜存在的情况下，网织红细胞脂氧合酶对乳化多不饱和脂肪酸的氧化速率急剧增加，且与掺入膜中的多不饱和脂肪酸量相关。磷脂酶A2对卵磷脂多不饱和酰基的水解极大地提高了其酶促氧化速率。结果表明，15-氢过氧花生四烯酸掺入卵磷脂脂质体的速率比未氧化的花生四烯酸慢得多。用去污剂溶解膜会导致激活作用消失。添加饱和卵磷脂脂质体会使网织红细胞脂氧合酶的蛋白质荧光猝灭，这表明该酶在与膜相互作用时其结构发生了构象变化。实验结果表明，游离的多不饱和膜脂肪酸是动物脂氧合酶的生理底物。膜中脂氧合酶反应速率升高的一个可能原因是该酶与膜基质相互作用时其构象发生了改变。
