Katayama T, Nakao K, Akamatsu M, Ueno T, Fujita T
Department of Agricultural Chemistry, Kyoto University, Japan.
J Pharm Sci. 1994 Sep;83(9):1357-62. doi: 10.1002/jps.2600830930.
The structure-hydrophobicity-antibacterial activity relationships of gramicidin S and its analogs retaining a beta-pleated sheet structure were examined quantitatively with physicochemical substituent and molecular parameters using regression analyses. Variations in their apparent hydrophobicity in an octanol/buffer (pH 7) system, log P' (O/W), were analyzed in terms of the "effective" hydrophobicity and steric parameters of side chain substituents of residues at certain positions in the molecule; however, some of the conformational factors have not been fully defined. For the partitioning into liposomes and the growth inhibitory activity against species of Gram-positive bacteria, the log P' (O/W) value simulated the hydrophobic effects of gramicidin S and its analogs better than substituent parameters. The side chain hydrophobicity was assumed to work together with effects attributed to variations in the entire cyclic peptide structure including conformational components undefined in the structure-log P' (O/W) analysis in these activities.
使用回归分析，通过物理化学取代基和分子参数对保留β-折叠结构的短杆菌肽S及其类似物的结构-疏水性-抗菌活性关系进行了定量研究。在辛醇/缓冲液（pH 7）体系中，根据分子中特定位置残基侧链取代基的“有效”疏水性和空间参数，分析了它们表观疏水性的变化，即log P'（O/W）；然而，一些构象因素尚未完全明确。对于脂质体分配和对革兰氏阳性菌的生长抑制活性，log P'（O/W）值比取代基参数能更好地模拟短杆菌肽S及其类似物的疏水效应。在这些活性中，假定侧链疏水性与整个环肽结构变化所产生的效应共同起作用，这些变化包括结构-log P'（O/W）分析中未明确的构象成分。
