To examine the role of the peptide main-chain length on the conformation and membrane activity of the lipopeptaibol antibiotic trichogin GA IV we have synthesized by solution methods the Leu11-OMe analogue and all its short, N-octanoylated C-terminal sequences. By FTIR absorption, 1H NMR and CD we have shown that largely folded, but not helical, forms characterize the short peptides, while the longest peptides predominantly adopt regular helical structures. Membrane activity is found in main-chain lengths as short as the tetrapeptide and progressively increases up to the undecapeptide.
为了研究肽主链长度对脂
多肽抗生素三肽GA IV的构象和膜活性的影响,我们采用溶液法合成了Leu11-OMe类似物及其所有短的N-辛酰化的C-末端序列。通过FTIR吸收、1H NMR和CD,我们发现短肽具有大折叠但无螺旋的特征,而最长肽则主要采用规则螺旋结构。我们发现膜活性存在于短至四肽的主链长度中,并逐渐增加到十一肽。