酶及寡聚化结构域影响类弹性蛋白多肽相变的规律及机制  

Influences of exogenous enzymes and foldons on the phase transition of elastin-like polypeptides and the underlying mechanisms

作　　者：葛慧华[1] 王心哲[1] 邱岳 张光亚[1] GE Huihua;WANG Xinzhe;QIU Yue;ZHANG Guangya(Department of Bioengineering and Biotechnology,College of Chemical Engineering,Huaqiao University,Xiamen,Fujian,361021)

机构地区：[1]华侨大学化工学院生物工程与技术系,厦门361021

出　　处：《应用与环境生物学报》2020年第6期1534-1539,共6页Chinese Journal of Applied and Environmental Biology

基　　金：中国大洋矿产资源研究开发协会项目(DY135-B2-07)资助。

摘　　要：了解外源酶对类弹性蛋白多肽(ELPs)相变温度及聚集所形成颗粒粒径大小及分布的规律,有助于高效利用非色谱纯化技术实现目标酶分离纯化,也为选择孔径合适的分离膜构建酶膜反应器提供依据.以ELPs40、寡聚化ELPs40(E-F)、寡聚化及线性的地衣多糖酶(B-E-F、B-E)和木聚糖酶(X-E-F、X-E)为研究对象,考察外源酶对ELPs40相变温度的影响.结果显示,引入地衣多糖酶及木聚糖酶分别将ELPs的相变温度提高了11℃和13℃;而寡聚化结构域Foldon却使B-E-F及X-E-F相变温度分别降低了8℃和11℃.此外,探究了NaCl、Na2SO4及Na2CO3对上述融合蛋白中ELPs相变温度的影响.结果显示,B-E-F在0.1-0.3 mol/L Na2CO3溶液中未发生相变,而在等浓度的Na2SO4溶液中则发生了明显相变,这一现象明显不符合Hofmeister离子序,这可能与地衣多糖酶和Foldon较低的等电点有关.It is important to investigate the influences of exogenous enzymes and foldons on the phase transition of elastin-like polypeptides(ELPs)and the micron-sized particles they self-assemble.These results are important for the efficient purification of target enzymes and selection of a separation membrane with an appropriate pore size to construct an enzyme membrane reactor.ELPs40,oligomerized ELPs40(E-F),oligomerized and linear lichenase(B-E-F and B-E),and xylanase(X-E-F and X-E)were chosen as subjects,and phase transition temperatures and particle sizes were determined.The results showed the phase transition temperature of ELPs increased by 11°C and 13°C with the introduction of lichenase and xylanase,while the phase transition temperature of B-E-F and X-E-F decreased by 8°C and 11°C with foldons,respectively.The effects of NaCl,Na2SO4,and Na2CO3 on the phase transition temperature of ELPs in the fusion proteins were also investigated.Interestingly,the phase transition of B-E-F was not observed in the Na2CO3 solution at concentrations of 0.1–0.3 mol/L,while it took place evidently in Na2SO4 solution with the same concentration,which was obviously inconsistent with the Hofmeister series.This might be related to the lower isoelectric points of lichenase and foldons.

关 键 词：蛋白寡聚化 相变温度 类弹性蛋白多肽 重组蛋白纯化 Hofmeister离子序 

分 类 号：Q51[生物学—生物化学]