生命科学研究2017，Vol.21Issue(4)：283-288,6.DOI:10.16605/j.cnki.1007-7847.2017.04.001
血红素对大肠杆菌铁蛋白稳定性及自组装的影响
Effect of Heme on the Stability and Self-assembly of Escherichia coli Bacterioferritin
摘要
Abstract
Bacterioferritin (BFR) from Escherichia coli is composed of 24 subunits that assemble into a large spherical cage with octahedral symmetry,with one heme molecule located at each C2 symmetry interface.To study the effect of heme on the protein stability and self-assembly,heme molecules were removed through site-directed mutagenesis.The mutant protein M52A was expressed,purified and characterized using size exclusion chromatography,transmission electron microscopy,UV-Vis spectroscopy and circular dichroism.Results indicated that although little effect was observed on the self-assembly of protein structure,removal of heme showed great impact on its thermostability.The melting temperature (Tm) of mutant M52A was 54.3 ℃,which was much lower than that of its wild type 69.9 ℃.Interestingly,when mutant M52A was incubated with hemin chloride,the melting temperature was restored to 67.7 ℃.Hence,heme molecules located at C2 symmetry interfaces in the bacterioferritin has a regulatory effect and plays a key role in the protein thermostability.关键词
细菌铁蛋白(BFR)/血红素/自组装/热力学稳定性Key words
bacterioferritin (BFR)/heme/self-assembly/thermostability分类
生物科学引用本文复制引用
张瑜,周金花,周亦琛,李迅,王飞..血红素对大肠杆菌铁蛋白稳定性及自组装的影响[J].生命科学研究,2017,21(4):283-288,6.基金项目
国家自然科学基金资助项目(31200564) （31200564）
江苏省高校自然科学研究面上项目(16KJB180009) （16KJB180009）
