State Key Laboratory of Marine Environmental Science and Key Laboratory of MOE for Coast and Wetland Ecosystems, School of Life Sciences, Xiamen University, Xiamen 361005, China; ShenZhen Research Institute of Xiamen University, ShenZhen, 518057, China.
State Key Laboratory of Marine Environmental Science and Key Laboratory of MOE for Coast and Wetland Ecosystems, School of Life Sciences, Xiamen University, Xiamen 361005, China.
J Hazard Mater. 2014 Aug 15;278:372-81. doi: 10.1016/j.jhazmat.2014.06.032. Epub 2014 Jun 24.
Toxicity of algicidal extracts from Mangrovimonas yunxiaonensis strain LY01 on Alexandrium tamarense were measured through studying the algicidal procedure, nuclear damage and transcription of related genes. Medium components were optimized to improve algicidal activity, and characteristics of algicidal extracts were determined. Transmission electron microscope analysis revealed that the cell structure was broken. Cell membrane integrity destruction and nuclear structure degradation were monitored using confocal laser scanning microscope, and the rbcS, hsp and proliferating cell nuclear antigen (PCNA) gene expressions were studied. Results showed that 1.0% tryptone, 0.4% glucose and 0.8% MgCl2 were the optimal nutrient sources. The algicidal extracts were heat and pH stable, non-protein and less than 1kD. Cell membrane and nuclear structure integrity were lost, and the transcription of the rbcS and PCNA genes were significantly inhibited and there was up-regulation of hsp gene expression during the exposure procedure. The algicidal extracts destroyed the cell membrane and nuclear structure integrity, inhibited related gene expression and, eventually, lead to the inhibition of algal growth. All the results may elaborate firstly the cell death process and nuclear damage in A. tamarense which was induced by algicidal extracts, and the algicidal extracts could be potentially used as bacterial control of HABs in future.
采用研究杀藻过程、细胞核损伤及相关基因转录的方法，测定了来源于海洋红杆菌 LY01 的杀藻提取物对塔玛亚历山大藻的毒性。优化了培养基成分以提高杀藻活性，并确定了杀藻提取物的特性。透射电子显微镜分析显示，细胞结构被破坏。利用共聚焦激光扫描显微镜监测细胞膜完整性的破坏和核结构的降解，并研究了 rbcS、hsp 和增殖细胞核抗原（PCNA）基因的表达。结果表明，1.0%的胰蛋白胨、0.4%的葡萄糖和 0.8%的 MgCl2 是最佳营养源。杀藻提取物具有热稳定性和 pH 稳定性，不是蛋白质且分子量小于 1kD。细胞膜和核结构完整性丧失，在暴露过程中 rbcS 和 PCNA 基因的转录受到显著抑制，hsp 基因的表达上调。杀藻提取物破坏了细胞膜和核结构的完整性，抑制了相关基因的表达，最终抑制了藻类的生长。所有结果可能首次阐述了塔玛亚历山大藻中由杀藻提取物诱导的细胞死亡过程和细胞核损伤，并且杀藻提取物将来可能被用作赤潮生物防治的细菌。
