期刊
JOURNAL OF PHYSICAL CHEMISTRY B
卷 115, 期 17, 页码 5026-5031出版社
AMER CHEMICAL SOC
DOI: 10.1021/jp2010716
关键词
-
资金
- NIH (USA) [GM05976]
- Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP, Brazil)
The function of membrane proteins is modulated by lipid bilayers. The permeation of ions in gramicidin A channels (gA) is markedly distinct in monoglyceride and phospholipid membranes. It was previously demonstrated that membrane phosphate headgroups accelerate the rate of proton transfer in gA. However, the permeation of alkalines in gA channels is considerably slower in phospholipid than in :monoglyceride membranes. In this study, gA channels were reconstituted in various membranes of ceramides, monoglycerides, phospholipids, or sphingolipids. It is 5 demonstrated that single channel conductances to alkalines are similar among bilayers consisting of :phospholipids and sphingolipids, and ceramides and monoglycerides. The presence of phosphate headgroups in membranes (and not the double acyl chains in lipids) attenuates alkaline permeation and enhances the proton transfer permeation in gA channels. In ceramide membranes in low ionic strength (<250 mM) solutions, gA channels become dysfunctional. The experimental results are discussed in regard to membrane/solution and membrane/protein interfaces.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据