Huertas María José, López-Maury Luis, Giner-Lamia Joaquín, Sánchez-Riego Ana María, Florencio Francisco Javier
Instituto de Bioquímica Vegetal y Fotosíntesis, Universidad de Sevilla-CSIC, Américo Vespucio 49, E-41092 Sevilla, Spain.
Systems Biology and Bioinformatics Laboratory, IBB-CBME, University of Algarve, Campus de Gambelas, 8005-139 Faro, Portugal.
Life (Basel). 2014 Dec 9;4(4):865-86. doi: 10.3390/life4040865.
Traces of metal are required for fundamental biochemical processes, such as photosynthesis and respiration. Cyanobacteria metal homeostasis acquires an important role because the photosynthetic machinery imposes a high demand for metals, making them a limiting factor for cyanobacteria, especially in the open oceans. On the other hand, in the last two centuries, the metal concentrations in marine environments and lake sediments have increased as a result of several industrial activities. In all cases, cells have to tightly regulate uptake to maintain their intracellular concentrations below toxic levels. Mechanisms to obtain metal under limiting conditions and to protect cells from an excess of metals are present in cyanobacteria. Understanding metal homeostasis in cyanobacteria and the proteins involved will help to evaluate the use of these microorganisms in metal bioremediation. Furthermore, it will also help to understand how metal availability impacts primary production in the oceans. In this review, we will focus on copper, nickel, cobalt and arsenic (a toxic metalloid) metabolism, which has been mainly analyzed in model cyanobacterium Synechocystis sp. PCC 6803.
金属痕迹是光合作用和呼吸作用等基本生化过程所必需的。蓝细菌的金属稳态起着重要作用，因为光合机制对金属有很高的需求，这使得金属成为蓝细菌生长的限制因素，尤其是在开阔海洋中。另一方面，在过去的两个世纪里，由于多种工业活动，海洋环境和湖泊沉积物中的金属浓度有所增加。在所有情况下，细胞都必须严格调节金属的摄取，以将细胞内金属浓度维持在有毒水平以下。蓝细菌具有在限制条件下获取金属以及保护细胞免受过量金属毒害的机制。了解蓝细菌中的金属稳态以及相关蛋白质，将有助于评估这些微生物在金属生物修复中的应用。此外，这也将有助于理解金属的可利用性如何影响海洋中的初级生产。在本综述中，我们将聚焦于铜、镍、钴和砷（一种有毒类金属）的代谢，这些主要是在模式蓝细菌聚球藻属PCC 6803中进行分析的。
