Biochemistry Department, Science College, King Saud University, Riyadh, Saudi Arabia.
Appl Biochem Biotechnol. 2012 Nov;168(5):1277-87. doi: 10.1007/s12010-012-9856-8. Epub 2012 Sep 7.
Stingray phospholipase A(2) group IIA (SPLA(2)-IIA) was recently isolated and purified to homogeneity from the intestine of the common stingray Dasyatis pastinaca, suggesting that this enzyme plays an important role in systemic bactericidal defense. The present study showed that SPLA(2)-IIA was highly bactericidal against Gram-positive bacteria with inhibition zones and minimal inhibitory concentration values in the range of 13-25 mm and 2-8 μg/ml, respectively, whereas Gram-negative bacteria exhibited a much higher resistance. The bactericidal efficiency of SPLA(2)-IIA was shown to be unaffected by high protein and salt concentrations, but dependent upon the presence of calcium ions, and then correlated to the hydrolytic activity of membrane phospholipids. Importantly, we showed that stingray phospholipase A(2) group IIA presents no cytotoxicity after its incubation with MDA-MB-231 cells. SPLA(2)-IIA may be considered as a future therapeutic agent against bacterial infections.
黄貂鱼磷脂酶 A2 组 IIA（SPLA2-IIA）最近从尖吻鲀的肠道中被分离和纯化到同质，这表明这种酶在全身杀菌防御中起着重要作用。本研究表明，SPLA2-IIA 对革兰氏阳性菌具有很强的杀菌作用，抑菌圈和最小抑菌浓度值分别在 13-25mm 和 2-8μg/ml 范围内，而革兰氏阴性菌的抗性要高得多。SPLA2-IIA 的杀菌效率不受高浓度蛋白质和盐的影响，但依赖于钙离子的存在，然后与膜磷脂的水解活性相关。重要的是，我们表明，黄貂鱼磷脂酶 A2 组 IIA 在与 MDA-MB-231 细胞孵育后没有细胞毒性。SPLA2-IIA 可以被认为是一种针对细菌感染的未来治疗剂。
