Palaniyar N, Ridsdale R A, Possmayer F, Harauz G
Department of Molecular Biology and Genetics, The University of Guelph, Guelph, Ontario, N1G 2W1, Canada.
Biochem Biophys Res Commun. 1998 Sep 8;250(1):131-6. doi: 10.1006/bbrc.1998.9284.
We have found by transmission electron microscopy that bovine surfactant protein A (SP-A) formed extended fibers in the presence of calcium. On phosphatidylcholine or especially dipalmitoylphosphatidylcholine monolayers, SP-A at roughly 0.005 mg/ml formed large numbers of fibers and elaborate fibrous networks. This observation suggested that the weak protein:protein interactions amongst free SP-As could be stabilized by phospholipids. In the presence of glycolipid GM1-ganglioside, SP-A's globular headgroup regions appeared enlarged and only small non-fibrous clusters were observed.
我们通过透射电子显微镜发现，牛表面活性蛋白A（SP-A）在有钙存在的情况下会形成延伸的纤维。在磷脂酰胆碱尤其是二棕榈酰磷脂酰胆碱单分子层上，约0.005 mg/ml的SP-A会形成大量纤维和精细的纤维网络。这一观察结果表明，游离SP-A之间微弱的蛋白质-蛋白质相互作用可被磷脂稳定。在糖脂GM1-神经节苷脂存在的情况下，SP-A的球状头部区域似乎增大，并且只观察到小的非纤维状聚集体。
