Deller R C, Carter B M, Zampetakis I, Scarpa F, Perriman A W
School of Cellular and Molecular Medicine, University of Bristol, Bristol, BS8 1TD, UK.
School of Cellular and Molecular Medicine, University of Bristol, Bristol, BS8 1TD, UK; Bristol Composites Institute (ACCIS), University of Bristol, Bristol, BS8 1TR, UK.
Biochem Biophys Res Commun. 2018 Jan 1;495(1):1055-1060. doi: 10.1016/j.bbrc.2017.11.073. Epub 2017 Nov 11.
The aim of this study was to examine the effect of chemical cationization on the structure and function of antifreeze protein III (AFP III) over an extreme temperature range (-40°C to +90°C) using far-UV synchrotron radiation circular dichroism (SRCD) and ice recrystallization inhibition (IRI) assays. Chemical cationization was able to produce a modified AFP III with a net cationic charge at physiological pH that had enhanced resistance to denaturation at elevated temperatures, with no immediate negative impact on protein structure at subzero temperatures. Furthermore, cationized AFP III retained an IRI activity similar to that of native AFP III. Consequently, chemical cationization may provide a pathway to the development of more robust antifreeze proteins as supplementary cryoprotectants in the cryopreservation of clinically relevant cells.
本研究的目的是使用远紫外同步辐射圆二色光谱（SRCD）和冰重结晶抑制（IRI）测定法，在极端温度范围（-40°C至+90°C）内研究化学阳离子化对抗冻蛋白III（AFP III）结构和功能的影响。化学阳离子化能够产生在生理pH下带净正电荷的修饰AFP III，其在高温下对变性的抗性增强，在零下温度下对蛋白质结构没有直接负面影响。此外，阳离子化的AFP III保留了与天然AFP III相似的IRI活性。因此，化学阳离子化可能为开发更强大的抗冻蛋白提供一条途径，作为临床相关细胞冷冻保存中的补充冷冻保护剂。
