Wang Jie, Wang Zhikai, Chen Xiaxia, Wang Wenxi, Huang Haiqing, Chen Yican, Du Zunqing, Zheng Zheng, Luo Xingzhang
Department of Environmental Science and Engineering, Fudan University, Shanghai, 200433, China.
Linping Branch, Hangzhou Municipal Ecology and Environment Bureau, Hangzhou, 311199, China.
Chemosphere. 2023 Jun;327:138506. doi: 10.1016/j.chemosphere.2023.138506. Epub 2023 Mar 24.
Deferoxamine (DFB) is a trihydroxamic acid siderophore that chelates with iron (Fe) to form iron-siderophore complexes. The existence of siderophores in nature changes the form of iron and affects the absorption and utilization of iron by organisms. However, the relationship between siderophores and the growth of Cyanobacteria is largely unknown. In this study, the cellular and transcriptomic responses to the addition of DFB were investigated. A high concentration of DFB (12 mg/L) significantly inhibited the growth of Cyanobacteria cells, reduced photosynthetic activity, and induced the production of peroxidase, with the highest inhibition rate of algal growth of 74.82%. These indexes were also affected for the low (3 mg/L) and medium concentration (6 mg/L) groups, but this difference is closely related to the growth stage of Cyanobacteria cells. This may be due to competition between the cell-associated iron-binding part/system and the extracellular Fe (Ⅲ)-DFB ligand. Transcriptome results showed that most of the genes involved in iron uptake and transport were down-regulated, and only the fur gene encoding the iron uptake regulator protein was significantly up-regulated. Most genes related to photosynthesis, glycolysis, and fatty acid metabolism were also down-regulated, while the obvious up-regulation of a few genes may be a complex regulation in response to the down-regulation of most genes. These findings will provide important insights into the effects of siderophores on iron bioavailability in algae.
去铁胺（DFB）是一种三羟基肟酸铁载体，它与铁（Fe）螯合形成铁-铁载体复合物。自然界中铁载体的存在改变了铁的形态，并影响生物体对铁的吸收和利用。然而，铁载体与蓝藻生长之间的关系在很大程度上尚不清楚。在本研究中，研究了添加DFB后的细胞和转录组反应。高浓度的DFB（12mg/L）显著抑制蓝藻细胞的生长，降低光合活性，并诱导过氧化物酶的产生，藻类生长的最高抑制率为74.82%。低浓度（3mg/L）和中浓度（6mg/L）组的这些指标也受到影响，但这种差异与蓝藻细胞的生长阶段密切相关。这可能是由于细胞相关的铁结合部分/系统与细胞外Fe（Ⅲ）-DFB配体之间的竞争。转录组结果表明，大多数参与铁吸收和转运的基因下调，只有编码铁吸收调节蛋白的fur基因显著上调。大多数与光合作用、糖酵解和脂肪酸代谢相关的基因也下调，而少数基因的明显上调可能是对大多数基因下调的一种复杂调节。这些发现将为铁载体对藻类中铁生物有效性的影响提供重要见解。
