Antonenko Yuri N, Stoilova Tatyana B, Kovalchuk Sergey I, Egorova Natalya S, Pashkovskaya Alina A, Sobko Alexander A, Kotova Elena A, Sychev Sergey V, Surovoy Andrey Y
Belozersky Institute of Physico-Chemical Biology, Moscow State University, 119992 Moscow, Russia.
FEBS Lett. 2005 Sep 26;579(23):5247-52. doi: 10.1016/j.febslet.2005.08.049.
Ion-channel activity of a series of gramicidin A analogues carrying charged amino-acid sequences on the C-terminus of the peptide was studied on planar bilayer lipid membranes and liposomes. It was found that the analogue with the positively charged sequence GSGRRRRSQS forms classical cationic pores at low concentrations and large unselective pores at high concentrations. The peptide was predominantly in the right-handed beta(6.3)-helical conformation in liposomes as shown by circular dichroism spectroscopy. The single-channel conductance of the large pore was estimated to be 320pS in 100mM choline chloride as judged from the fluctuation analysis of the multi-channel current. The analogue with the negatively charged sequence GSGEEEESQS exhibited solely classical cationic channel activity. The ability of a peptide to form different type of channels can be used in the search for broad-spectrum antibiotics.
在平面双层脂质膜和脂质体上研究了一系列在肽的C末端带有带电氨基酸序列的短杆菌肽A类似物的离子通道活性。发现带有带正电序列GSGRRRRSQS的类似物在低浓度时形成经典的阳离子孔，在高浓度时形成大的非选择性孔。如圆二色光谱所示，该肽在脂质体中主要呈右手β(6.3) - 螺旋构象。根据多通道电流的波动分析判断，在100mM氯化胆碱中，大孔的单通道电导估计为320pS。带有带负电序列GSGEEEESQS的类似物仅表现出经典的阳离子通道活性。肽形成不同类型通道的能力可用于寻找广谱抗生素。
