SURFACTANT PROTEIN-B - LIPID INTERACTIONS OF SYNTHETIC PEPTIDES REPRESENTING THE AMINO-TERMINAL AMPHIPATHIC DOMAIN
SURFACTANT PROTEIN-B - LIPID INTERACTIONS OF SYNTHETIC PEPTIDES REPRESENTING THE AMINO-TERMINAL AMPHIPATHIC DOMAIN
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DOI：
10.1073/pnas.88.16.7451
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发表时间：
1991-08-01
影响因子：
11.1
通讯作者：
WARING, AJ
中科院分区：
文献类型：
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作者：
BRUNI, R;TAEUSCH, HW;WARING, AJ
肺表面活性蛋白 B (SP-B) 影响表面活性剂脂质表面活性的机制尚不清楚。我们通过比较基于天然人 SP-B 序列并通过位点特异性氨基酸取代修饰的合成肽家族的二级构象和表面活性，研究了 SP-B 氨基末端两亲结构域的肽/脂质相互作用。圆二色性测量显示α螺旋结构与肽与脂质相互作用的能力以及肽/脂质分散体的表面活性相关。改变残基的电荷或疏水性的氨基酸取代降低了螺旋含量并减少了氨基末端片段与脂质分散体的结合。肽/脂质混合物的表面活性通过合成肽中的电荷反转而最大程度地改变。这些观察结果表明，静电相互作用和疏水性是确定脂质分散体中表面活性剂肽的最佳结构和功能的重要因素。
The mechanisms by which pulmonary surfactant protein B (SP-B) affects the surface activity of surfactant lipids are unclear. We have studied the peptide/lipid interactions of the amino-terminal amphipathic domain of SP-B by comparing the secondary conformations and surface activities of a family of synthetic peptides based on the native human SP-B sequence, modified by site-specific amino acid substitutions. Circular dichroism measurements show an alpha-helical structure correlating with the ability of the peptides to interact with lipids and with the surface activity of peptide/lipid dispersions. Amino acid substitutions altering either the charge or the hydrophobicity of the residues lowered the helical content and reduced the association of the amino-terminal segment with lipid dispersions. Surface activity of peptide/lipid mixtures was maximally altered by reversal of charge in synthetic peptides. These observations indicate that electrostatic interactions and hydrophobicity are important factors in determining optimal structure and function of surfactant peptides in lipid dispersions.