GATED PORES IN THE FERRITIN PROTEIN NANOCAGE.
GATED PORES IN THE FERRITIN PROTEIN NANOCAGE.
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DOI：
10.1016/j.ica.2007.08.025
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发表时间：
2008-03
影响因子：
2.8
通讯作者：
Elizabeth C. Theil;Xiaofeng S. Liu;T. Tosha
中科院分区：
文献类型：
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作者：
Elizabeth C. Theil;Xiaofeng S. Liu;T. Tosha
铁蛋白门控孔的性质控制蛋白纳米笼内水合氧化物矿物中三价铁的FMNH 2还原速率，并从以下方面进行讨论：（1）保守的孔门残基（离子对：精氨酸72，天冬氨酸122，和疏水对，亮氨酸110-亮氨酸134），（2）孔在低于纳米笼本身的温度30 ℃下对热的敏感性，和（3）孔隙对尿素（1- 10 mM）的生理变化的敏感性。改变溶液中铁蛋白孔结构/功能的条件，再加上孔门的高度进化保守性，表明体内存在分子调节剂，其识别孔门并根据生物铁需求保持它们关闭或打开。通过铁蛋白纳米笼中的门控孔的亚铁离子运输和通过嵌入细胞膜中的离子通道蛋白中的门控孔的离子运输之间的明显同源性，使得水溶性铁蛋白和孔门控折叠/解折叠的研究成为其他门控孔的有用模型。
Properties of ferritin gated pores control rates of FMNH2reduction of ferric iron in hydrated oxide minerals inside the protein nanocage, and are discussed in terms of: (1) the conserved pore gate residues (ion pairs: arginine 72, aspartate 122, and a hydrophobic pair, leucine 110–leucine 134), (2) pore sensitivity to heat at temperatures 30°C below that of the nanocage itself, and (3) pore sensitivity to physiological changes in urea (1–10mM). Conditions which alter ferritin pore structure/function in solution, coupled with the high evolutionary conservation of the pore gates, suggest the presence of molecular regulators in vivo that recognize the pore gates and hold them either closed or open, depending on biological iron need. The apparent homology between ferrous ion transport through gated pores in the ferritin nanocage and ion transport through gated pores in ion channel proteins embedded in cell membranes, make studies of water soluble ferritin and the pore gating folding/unfolding a useful model for other gated pores.