Irreversible unfolding of the neutral pH form of influenza hemagglutinin demonstrates that it is not in a metastable state
Irreversible unfolding of the neutral pH form of influenza hemagglutinin demonstrates that it is not in a metastable state
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DOI：
10.1021/bi034094b
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发表时间：
2003-05-06
期刊：
影响因子：
2.9
通讯作者：
Epand, RM
中科院分区：
文献类型：
--
作者：
Epand, RF;Epand, RM
流感病毒的蛋白质的热变性已经通过差示扫描量热法在存在和不存在脂质的情况下作为扫描速率的函数来测量。我们应用不可逆热力学的理论来获得活化能。在含有神经节苷脂（GD（1a））的二油酰磷脂酰胆碱脂质体存在下，血凝素蛋白的变性温度降低。这种热稳定性的降低也反映在圆二色性光谱的温度依赖性中。准弹性光散射证实，含有GD1a的脂质体与病毒相互作用，并抑制作为温度函数的颗粒尺寸的增长。虽然病毒可以在较高温度下与脂质体融合，但该过程的焓变不可检测。我们的研究结果还表明，紧凑的折叠结构的流感血凝素蛋白是不是一个动力学捕获的亚稳态高能量形式。
The thermal denaturation of the proteins of influenza virus has been measured by differential scanning calorimetry in the presence and absence of lipids as a function of scan rate. We have applied theories of irreversible thermodynamics to obtain the activation energy. In the presence of liposomes of dioleoylphosphatidylcholine with the ganglioside, GD(1a), the denaturation temperature of the hemagglutinin protein is lowered. This lowering of thermal stability is also reflected in the temperature dependence of the circular dichroism spectra. Quasi-elastic light scattering confirms that liposomes containing GD1a interact with the virus and inhibit the growth in the size of the particle as a function of temperature. Although the virus can fuse with the liposomes at higher temperatures, the enthalpy change for this process is not detectable. Our results also demonstrate that the compact folded structure of the influenza hemagglutinin protein is not a kinetically trapped metastable high-energy form.