title: Compatible solutes: ectoine and hydroxyectoine improve functional nanostructures in artificial lung surfactants.
abstract: Ectoine and hydroxyectoine belong to the family of compatible solutes and are among the most abundant osmolytes in nature. These compatible solutes protect biomolecules from extreme conditions and maintain their native function. In the present study, we have investigated the effect of ectoine and hydroxyectoine on the domain structures of artificial lung surfactant films consisting of dipalmitoylphosphatidylcholine (DPPC), dipalmitoylphosphatidylglycerol (DPPG) and the lung surfactant specific surfactant protein C (SP-C) in a molar ratio of 80:20:0.4. The pressure-area isotherms are found to be almost unchanged by both compatible solutes. The topology of the fluid domains shown by scanning force microscopy, which is thought to be responsible for the biophysical behavior under compression, however, is modified giving rise to the assumption that ectoine and hydroxyectoine are favorable for a proper lung surfactant function. This is further evidenced by the analysis of the insertion kinetics of lipid vesicles into the lipid-peptide monolayer, which is clearly enhanced in the presence of both compatible solutes. Thus, we could show that ectoine and hydroxyectoine enhance the function of lung surfactant in a simple model system, which might provide an additional rationale to inhalative therapy.
authors: Institute of Biochemistry, Westfälische Wilhelms Universität, Wilhelm Klemm Str. 2, 48149 Münster, Germany.
authors: Rakesh Kumar
authors: RK
authors: Harishchandra
authors: Amit Kumar
authors: AK
authors: Sachan
authors: Andreas
authors: A
authors: Kerth
authors: Georg
authors: G
authors: Lentzen
authors: Thorsten
authors: T
authors: Neuhaus
authors: Hans-Joachim
authors: HJ
authors: Galla
mesh_terms: D000599:Amino Acids, Diamino / Q000737:chemistry*; D018625:Microscopy, Atomic Force; D049329:Nanostructures; D011663:Pulmonary Surfactants / Q000737:chemistry*; D012995:Solubility
chemical_list: D000599:Amino Acids, Diamino; D011663:Pulmonary Surfactants; C121557:hydroxyectoine; C045628:ectoine