John Innes Centre and University of East Anglia, Norwich Research Park, Norwich NR4 7UH, United Kingdom; email:
Annu Rev Plant Biol. 2014;65:125-53. doi: 10.1146/annurev-arplant-050213-035759. Epub 2014 Jan 29.
Iron is an essential element for all photosynthetic organisms. The biological use of this transition metal is as an enzyme cofactor, predominantly in electron transfer and catalysis. The main forms of iron cofactor are, in order of decreasing abundance, iron-sulfur clusters, heme, and di-iron or mononuclear iron, with a wide functional range. In plants and algae, iron-sulfur cluster assembly pathways of bacterial origin are localized in the mitochondria and plastids, where there is a high demand for these cofactors. A third iron-sulfur cluster assembly pathway is present in the cytosol that depends on the mitochondria but not on plastid assembly proteins. The biosynthesis of heme takes place mainly in the plastids. The importance of iron-sulfur cofactors beyond photosynthesis and respiration has become evident with recent discoveries of novel iron-sulfur proteins involved in epigenetics and DNA metabolism. In addition, increased understanding of intracellular iron trafficking is opening up research into how iron is distributed between iron cofactor assembly pathways and how this distribution is regulated.
铁是所有光合生物的必需元素。这种过渡金属的生物利用形式是作为酶辅因子，主要参与电子传递和催化。铁辅因子的主要形式按丰度递减的顺序依次为铁硫簇、血红素、二铁或单核铁，具有广泛的功能范围。在植物和藻类中，细菌起源的铁硫簇组装途径定位于线粒体和质体中，这些细胞器对这些辅因子的需求量很大。第三种铁硫簇组装途径存在于依赖线粒体但不依赖质体组装蛋白的细胞质中。血红素的生物合成主要发生在质体中。随着最近发现涉及表观遗传学和 DNA 代谢的新型铁硫蛋白，铁硫辅因子在光合作用和呼吸作用之外的重要性变得显而易见。此外，对细胞内铁运输的深入了解正在开辟研究铁在铁辅因子组装途径之间的分布以及这种分布如何受到调节的途径。
