A function of lung surfactant protein SP-B.
A function of lung surfactant protein SP-B.
复制标题
肺表面活性蛋白 SP-B 的功能。
DOI：
10.1126/science.8332910
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发表时间：
1993
期刊：
影响因子：
--
通讯作者：
Waring,AJ
中科院分区：
文献类型：
--
作者：
Longo,ML;Bisagno,AM;Zasadzinski,JA;Bruni,R;Waring,AJ
肺表面活性物质的主要功能是在肺泡界面形成单层，能够将正常表面张力降低至接近零。为了完成这一过程，表面活性剂必须能够保持一个连贯的，紧密堆积的单层，避免在呼气过程中崩溃。肺表面活性剂特异性蛋白SP-B的带正电荷的氨基末端肽SP-B1-25将肺表面活性剂的重要组分棕榈酸（PA）的塌陷压力增加到近70毫牛顿/米。PA等温线的这种改变消除了从肺表面活性物质的主要二棕榈酰磷脂酰胆碱单层中“挤出”脂肪酸的驱动力。SP-B1-25的不带电突变体诱导的等温线变化不大，这表明阳离子肽和阴离子脂质之间的特定电荷相互作用是负责的稳定。SP-B1-25对脂肪酸等温线的影响与简单聚阳离子的影响非常相似，这表明这种聚合物可能用作治疗呼吸窘迫综合征的替代表面活性剂的组分。
The primary function of lung surfactant is to form monolayers at the alveolar interface capable of lowering the normal surface tension to near zero. To accomplish this process, the surfactant must be capable of maintaining a coherent, tightly packed monolayer that avoids collapse during expiration. The positively charged amino-terminal peptide SP-B1-25 of lung surfactant-specific protein SP-B increases the collapse pressure of an important component of lung surfactant, palmitic acid (PA), to nearly 70 millinewtons per meter. This alteration of the PA isotherms removes the driving force for "squeeze-out" of the fatty acids from the primarily dipalmitoylphosphatidylcholine monolayers of lung surfactant. An uncharged mutant of SP-B1-25 induced little change in the isotherms, suggesting that a specific charge interaction between the cationic peptide and the anionic lipid is responsible for the stabilization. The effect of SP-B1-25 on fatty acid isotherms is remarkably similar to that of simple poly-cations, suggesting that such polymers might be useful as components of replacement surfactants for the treatment of respiratory distress syndrome.