Metal acquisition and availability in the mitochondria.
Metal acquisition and availability in the mitochondria.
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DOI：
10.1021/cr900006y
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发表时间：
2009-10
期刊：
影响因子：
62.1
通讯作者：
Winge, Dennis R.
中科院分区：
文献类型：
--
作者：
Atkinson, Aaron;Winge, Dennis R.
不同的金属离子在蛋白质的结构和功能中起着多种作用。金属离子除了在催化、电子转移和配体结合方面的作用外，对许多蛋白质的结构完整性也很重要。已知生理反应可确保细胞内必需金属离子的充足水平，但对蛋白质金属化过程和细胞室（如线粒体）内金属离子的可用性知之甚少。一般来说，金属化反应预计发生在蛋白质生物合成期间或之后不久，因为许多金属辅助因子是蛋白质稳定性的重要决定因素。在细胞质核糖体上，蛋白质的生物合成和链延伸与伴侣蛋白介导的蛋白质折叠相耦合。新生多肽在核糖体内受到保护，只有当它们从出口通道出来时才能折叠。分子伴侣与新生多肽结合，通过结合和释放的循环，积极引导多肽折叠。有些蛋白质在最终从核糖体中释放出来之前就获得了天然的构象。2,3金属蛋白可能在这一阶段被金属化。生物金属化依赖于足够的生物可利用金属离子池的可用性和选择机制，以确保金属化与适当的金属离子。特异性金属化是一个重要的问题，因为蛋白质在结合各种金属离子之间只有有限的区别。对金属化的有限控制是由多个金属离子之间配位几何和配体给体原子的硬度/柔软度的不同偏好所施加的。此外，对于金属离子，如锌（II），这些强加的限制更灵活。由于锌（II）的临界硬度，锌（II）能够与多种给体配位，并且由于锌（II）缺乏任何配体场稳定效应，配位数之间的转换是可能的。这些效应有可能增加精确锌位点金属化的难度和锌与其他金属蛋白的错误结合。
Diverse metal ions participate in multiple roles in protein structure and function. In addition to their role in catalysis, electron transfer, and ligand binding, metal ions are important for the structural integrity of many proteins. Physiological responses are known to ensure adequate cellular levels of essential metal ions, but less is known about both the process of protein metalation and metal ion availability within cellular compartments such as the mitochondrion. In general, metalation reactions are expected to occur during protein biosynthesis or shortly thereafter, since many metal cofactors are important determinants of protein stability. On cytoplasmic ribosomes, protein biosynthesis and chain elongation are coupled to chaperone-mediated protein folding for many proteins. 1 Nascent polypeptides are protected within the ribosome and can only fold as they emerge from the exit tunnel. The molecular chaperones bind to nascent polypeptides and actively guide the polypeptides in folding through cycles of binding and release. Some proteins achieve a native conformer before final release from the ribosome. 2, 3 Metalloproteins are likely metalated at this stage. Biological metalation is dependent on both the availability of adequate bioavailable pools of metal ion and selectivity mechanisms to ensure metalation with the appropriate metal ion.Specific metalation is a significant issue, as proteins have only limited discrimination between binding various metal ions. Limited control over metalation is imposed by diverse preferences in coordination geometry and hardness/softness of ligand donor atoms between multiple metal ions. Moreover, for metal ions such as Zn (II), these imposed limits are more flexible. Zn (II) is able to coordinate with a variety of donor ligands due to its borderline hardness, and conversion between coordination numbers is possible due to a lack of any ligand field stabilization effects for Zn (II). These effects have the potential to raise both the difficulty in precise Zn site metalation and the misincorporation of Zn into other metalloproteins.
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影响因子：
4.8
作者：
Burri, L;Vascotto, K;Lithgow, T
通讯作者：
Lithgow, T
影响因子：
20.3
作者：
Cavadini, Patrizia;Biasiotto, Giorgio;Arosio, Paolo
通讯作者：
Arosio, Paolo
影响因子：
4.8
作者：
Cobine, Paul A.;Pierrel, Fabien;Winge, Dennis R.
通讯作者：
Winge, Dennis R.
影响因子：
4.8
作者：
Bianchi, C;Genova, ML;Lenaz, G
通讯作者：
Lenaz, G
DOI：
10.1073/pnas.0800019105
发表时间：
2008-05-13
影响因子：
11.1
作者：
Banci, Lucia;Bertini, Ivano;Palumaa, Peep
通讯作者：
Palumaa, Peep