Kullman Lisen, Gurnev Philip A, Winterhalter Mathias, Bezrukov Sergey M
Laboratory of Physical and Structural Biology, NICHD, NIH, Bethesda, Maryland 20892-0924, USA.
Phys Rev Lett. 2006 Jan 27;96(3):038101. doi: 10.1103/PhysRevLett.96.038101. Epub 2006 Jan 23.
We study fluctuations in ion conductance and enzymatic rates of the sugar-specific channel-forming membrane protein, Maltoporin, at the single-molecule level. Specifically, we analyze time-persistent deviations in the transport parameters of individual channels from the multichannel averages and discuss our findings in the context of static disorder in protein folding. We show that the disorder responsible for variations in ion conductance does not affect sugar binding, suggesting that Maltoporin can exist in a wide set of fully functional, yet distinctly different, subconformations.
我们在单分子水平上研究了糖特异性通道形成膜蛋白麦芽糖孔蛋白的离子电导和酶促速率的波动情况。具体而言，我们分析了单个通道的转运参数相对于多通道平均值的持续时间偏差，并在蛋白质折叠的静态无序背景下讨论了我们的发现。我们表明，导致离子电导变化的无序并不影响糖结合，这表明麦芽糖孔蛋白可以以多种功能完全正常但明显不同的亚构象存在。
