文献类型：期刊文献

英文题名：Temperature Influence on the Structure and Interfacial Properties of Surfactin Micelle: A Molecular Dynamics Simulation Study

作者：She, An-Qi[1,2];Gang, Hong-Ze[1,2];Mu, Bo-Zhong[1,2]

机构：[1]E China Univ Sci & Technol, State Key Lab Bioreactor Engn, Shanghai 200237, Peoples R China;[2]E China Univ Sci & Technol, Inst Appl Chem, Shanghai 200237, Peoples R China

年份：2012

卷号：116

期号：42

起止页码：12735

外文期刊名：JOURNAL OF PHYSICAL CHEMISTRY B

收录：;EI(收录号：20124415616843);WOS:【SCI-EXPANDED(收录号:WOS:000310120900011)】；

基金：This work was supported by the National Natural Science Foundation of China (Grant No. 21203063).

语种：英文

外文关键词：Peptides - Hydrogen bonds - Chains - Bacteriology - Hydrocarbons - Temperature distribution - Conformations - Molecular dynamics - Flip flop circuits

摘要：Surfactin is an efficient biosurfactant excreted by different strains of Bacillus subtilis. Our study provides a molecular view of the temperature dependence of the structure and the interfacial properties of un-ionized surfactin micelles. The overall size and shape, the surface area, the radial density distribution of the micelles, the conformation of the hydrocarbon chain, and the intramolecular/intermolecular hydrogen bonds formed in surfactin molecules were investigated. The micelles were mostly in sphere shapes, and the radii of surfactin micelle were estimated to be around 2.2 nm. The peptide rings occupied most of the surface of the micelles. Small amounts of beta-turn and gamma-turn structures were found in the conformations of the peptide rings. When the temperature increased, the shape of the peptide rings became planar; the solvent accessible surface area decreased as temperature dehydration occurred. At 343 K some hydrocarbon chains reversed their orientation (flip-flopped). In addition, the stability of the hydrogen bond interactions in the micelles decreases with the increasing temperature.