Conservation of the structural and functional architecture of encapsulated ferritins in bacteria and archaea
Conservation of the structural and functional architecture of encapsulated ferritins in bacteria and archaea
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细菌和古细菌中封装铁蛋白的结构和功能结构的保护
DOI：
10.1101/431494
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发表时间：
2018
期刊：
影响因子：
--
通讯作者：
He D
中科院分区：
文献类型：
--
作者：
He D
铁蛋白是一个大家族的细胞内蛋白质，其通过催化将Fe（II）转化为毒性较小的Fe（III）并将铁矿物储存在其核心内来保护细胞免受氧化应激。包封铁蛋白（EncFtn）是铁蛋白样蛋白的一个亚家族，广泛分布于所有细菌和古细菌门中。最近characterizedRhodocellum rubrum EncFtn显示一个不寻常的结构相比，经典的铁蛋白，具有开放的十聚体结构，是酶活性，但不能存储铁。这种EncFtn必须与一个铁纳米笼相关联，以便充当铁储存。鉴于EncFtn家族在具有不同环境生态位的生物体中的广泛分布，出现了一个问题，即这种不寻常的结构是否在整个家族中保守。在这里，我们表征EncFtn蛋白从嗜盐Haliangium ochraceum和嗜热Pyrococcus furiosus，这表明保守的环状五聚体的二聚体拓扑结构。同源物之间的关键结构差异是明显的，特别是在环的中心和二级金属结合位点，这在同源物中是不保守的。溶液和天然质谱分析强调，蛋白质四级结构的稳定性在来自不同物种的EncFtn蛋白质之间不同。EncFtn蛋白的铁氧化酶活性得到证实，我们表明，虽然铁氧化酶中心周围的四级结构是不同的经典铁蛋白，铁氧化酶活性仍然被抑制Zn（II）。我们的研究结果突出了EncFtn蛋白的共同结构组织和活性，尽管不同的宿主环境和背景内的cefrin。
Ferritins are a large family of intracellular proteins that protect the cell from oxidative stress by catalytically converting Fe(II) into less toxic Fe(III) and storing iron minerals within their core. Encapsulated ferritins (EncFtn) are a sub-family of ferritin-like proteins, which are widely distributed in all bacterial and archaeal phyla. The recently characterizedRhodospirillum rubrumEncFtn displays an unusual structure when compared with classical ferritins, with an open decameric structure that is enzymatically active, but unable to store iron. This EncFtn must be associated with an encapsulin nanocage in order to act as an iron store. Given the wide distribution of the EncFtn family in organisms with diverse environmental niches, a question arises as to whether this unusual structure is conserved across the family. Here, we characterize EncFtn proteins from the halophileHaliangium ochraceumand the thermophilePyrococcus furiosus, which show the conserved annular pentamer of dimers topology. Key structural differences are apparent between the homologues, particularly in the centre of the ring and the secondary metal-binding site, which is not conserved across the homologues. Solution and native mass spectrometry analyses highlight that the stability of the protein quaternary structure differs between EncFtn proteins from different species. The ferroxidase activity of EncFtn proteins was confirmed, and we show that while the quaternary structure around the ferroxidase centre is distinct from classical ferritins, the ferroxidase activity is still inhibited by Zn(II). Our results highlight the common structural organization and activity of EncFtn proteins, despite diverse host environments and contexts within encapsulins.
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影响因子：
3
作者：
Chasteen, ND;Harrison, PM
通讯作者：
Harrison, PM
影响因子：
5.4
作者：
DasSarma S;DasSarma P
通讯作者：
DasSarma P
一致。
DOI：
10.1097/iae.0000000000001602
发表时间：
2017
期刊：
Retina (Philadelphia, Pa.)
影响因子：
--
作者：
Todorich,Bozho;Thanos,Aristomenis;Yonekawa,Yoshihiro;Thomas,BenjaminJ;Faia,LisaJ;Chang,Emmanuel;Shulman,Julia;Olsen,KarlR;Blair,MichaelP;Shapiro,MichaelP;Ferrone,Philip;Vajzovic,Lejla;Toth,CynthiaA;Lee,ThomasC;Robinson,
通讯作者：
Robinson,
影响因子：
6.2
作者：
Snijder, Joost;Kononova, Olga;Heck, Albert J. R.
通讯作者：
Heck, Albert J. R.