Ghosh Sudeshna, Pandey Nitin K, Dasgupta Swagata
Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur 721302, India.
Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur 721302, India.
J Photochem Photobiol B. 2014 Sep 5;138:8-16. doi: 10.1016/j.jphotobiol.2014.04.021. Epub 2014 May 5.
Molten globule state plays a crucial role in the amyloidogenesis of several proteins. Hen egg white lysozyme (HEWL) acquires a molten globule state at alkaline pH (12.75). Our study reveals a significant inhibitory effect of high molecular weight polyethylene glycols (PEG) (PEG 20000 and PEG 35000) against alkali-salt mediated fibrillation of HEWL. Native state of HEWL is stabilized in the presence of PEGs accompanied by a decrease in the β-sheet content. Enzymatic activity of HEWL is mostly retained in the presence of polyethylene glycols. The comparable hydrodynamic radius (Rh) of PEG 20000 and native HEWL is central reason to the greater inhibitory potency of PEG 20000 against HEWL fibrillation.
熔球态在几种蛋白质的淀粉样变过程中起着关键作用。鸡蛋清溶菌酶（HEWL）在碱性pH值（12.75）下会形成熔球态。我们的研究揭示了高分子量聚乙二醇（PEG）（PEG 20000和PEG 35000）对HEWL碱盐介导的纤维化具有显著抑制作用。在PEG存在下，HEWL的天然状态得以稳定，同时β-折叠含量降低。在聚乙二醇存在下，HEWL的酶活性大多得以保留。PEG 20000与天然HEWL具有相当的流体力学半径（Rh），这是PEG 20000对HEWL纤维化具有更强抑制效力的主要原因。
