Structural Basis of Novel Interactions Between the Small-GTPase and GDI-like Domains in Prokaryotic FeoB Iron Transporter
Structural Basis of Novel Interactions Between the Small-GTPase and GDI-like Domains in Prokaryotic FeoB Iron Transporter
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DOI：
10.1016/j.str.2009.08.007
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发表时间：
2009-10-14
期刊：
影响因子：
5.7
通讯作者：
Nureki, Osamu
中科院分区：
文献类型：
--
作者：
Hattori, Motoyuki;Jin, Yaohua;Nureki, Osamu
FeoB家族蛋白是广泛分布的原核细胞膜蛋白，参与Fe 2+的摄取。FeoB由N-末端胞质和C-末端跨膜结构域组成。胞质结构域的N-末端区域与小G蛋白同源，并被认为调节Fe 2+摄取。据报道，连接G和TM结构域的间隔区作为GDP解离抑制剂（GDI）样结构域起作用，其稳定GDP结合状态。然而，G和GDI样结构域在铁摄取中的功能仍不清楚。在这里，我们报告的结构和功能分析的FeoB胞质结构域从海栖热袍菌。基于结构的突变分析表明，G和GDI样结构域之间的相互作用是重要的GDI和Fe 2+摄取活动。在此基础上，我们提出了一个调节机制的Fe 2+吸收。
The FeoB family proteins are widely distributed prokaryotic membrane proteins involved in Fe2+ uptake. FeoB consists of N-terminal cytosolic and C-terminal transmembrane domains. The N-terminal region of the cytosolic domain is homologous to small GTPase (G) proteins and is considered to regulate Fe2+ uptake. The spacer region connecting the G and TM domains reportedly functions as a GDP dissociation inhibitor (GDI)-like domain that stabilizes the GDP-binding state. However, the function of the G and GDI-like domains in iron uptake remains unclear. Here, we report the structural and functional analyses of the FeoB cytosolic domain from Thermotoga maritima. The structure-based mutational analysis indicated that the interaction between the G and GDI-like domains is important for both the GDI and Fe2+ uptake activities. On the basis of these results, we propose a regulatory mechanism of Fe2+ uptake.