DePaul University, Department of Chemistry, 1110 W. Belden Avenue, Chicago, IL 60614, United States.
DePaul University, Department of Chemistry, 1110 W. Belden Avenue, Chicago, IL 60614, United States.
Mol Immunol. 2014 Aug;60(2):103-8. doi: 10.1016/j.molimm.2014.04.005. Epub 2014 May 8.
The deglycosylation of immunoglobulin G (IgG) antibodies leads to a diminished immune response. This reduction in immune response is thought to arise from weakened binding of IgG antibodies to effector molecules as a result of a conformational change in the antibody. The nature of this structural alteration is uncertain due to the conflicting results obtained from different experimental methods. We have examined the impact of deglycosylation by the endoglycosidase PNGase F on the structure of the Fc region of a human IgG antibody using single molecule Förster Resonance Energy Transfer (FRET). The FRET efficiency histograms obtained indicate that the structure of the Fc region becomes more flexible upon deglycosylation. This is demonstrated by a change in the width of the energy transfer efficiency peak, which increases from 0.19 ± 0.02 to 0.6 ± 0.1 upon deglycosylation.
免疫球蛋白 G（IgG）抗体的去糖基化会导致免疫反应减弱。这种免疫反应的降低被认为是由于抗体构象的变化导致 IgG 抗体与效应分子的结合减弱所致。由于不同实验方法得到的结果相互矛盾，因此这种结构改变的性质尚不确定。我们使用单分子Förster 共振能量转移（FRET）技术研究了内切糖苷酶 PNGase F 对人 IgG 抗体 Fc 区域结构的去糖基化作用。得到的 FRET 效率直方图表明，Fc 区域的结构在去糖基化后变得更加灵活。这一点可以通过能量转移效率峰的宽度变化来证明，该峰的宽度从去糖基化前的 0.19 ± 0.02 增加到 0.6 ± 0.1。
