School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China.
School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China; Guangdong Provincial Key Laboratory of Marine Resources and Coastal Engineering, School of Marine Sciences, Sun Yat-Sen University, Guangzhou 510275, China.
Sci Total Environ. 2019 Nov 1;689:287-294. doi: 10.1016/j.scitotenv.2019.06.162. Epub 2019 Jun 15.
Collaborations between multiple microbial species are important for understanding natural clearance and ecological effects of toxic organic contaminants in the environment. However, the interactions between different species in the transformation and degradation of contaminants remain to address. In this study, the effects of pyrene and its bacterial metabolites on the algal growth (Selenastrum capricornutum) were examined. The specific growth rate of algal cells incubated with bacterial pyrene metabolites (1.18 d) was highest among all treatment, followed by the controls (1.07 d), treated with pyrene-free bacterial metabolites (1.04 d) and those treated with pyrene (0.55 d). G phase is the key growth phase for the cells to synthesize biomolecules for subsequent cell division in the cell cycle. Approximately 76.9% of the cells treated with bacterial pyrene metabolites were at the G phase and significantly lower than those with the controls (85.3%), pyrene-free bacterial metabolites (85.5%) and pyrene treatment (92.5%). Transcriptomic analysis of algae showed that the expression of 47 ribosomal unigenes was down-regulated by 5 mg L of pyrene, while 308 unigenes related to the preparation of cell division (DNA replication and protein synthesis) were up-regulated by bacterial pyrene metabolites. It indicated that basal metabolism associated with the growth and proliferation of algal cells could be significantly promoted by bacterial pyrene metabolites. Overall, this study suggests a close relationship between algae and bacteria in the transformation and ecological effects of toxic contaminants.
多种微生物物种之间的协作对于理解环境中有毒有机污染物的自然清除和生态效应非常重要。然而，不同物种在污染物转化和降解过程中的相互作用仍有待解决。在本研究中，研究了芘及其细菌代谢物对藻类生长（铜绿微囊藻）的影响。与所有处理组相比，用细菌芘代谢物孵育的藻类细胞的特定生长率最高（1.18d），其次是对照组（1.07d）、用无芘细菌代谢物处理的组（1.04d）和用芘处理的组（0.55d）。G 期是细胞合成用于随后细胞分裂的生物分子的关键生长阶段。用细菌芘代谢物处理的细胞中约 76.9%处于 G 期，明显低于对照组（85.3%）、无芘细菌代谢物（85.5%）和芘处理组（92.5%）。藻类的转录组分析表明，47 个核糖体基因的表达被 5mg/L 的芘下调，而与细胞分裂准备（DNA 复制和蛋白质合成）相关的 308 个基因则被细菌芘代谢物上调。这表明与藻类细胞的生长和增殖相关的基础代谢可以被细菌芘代谢物显著促进。总的来说，本研究表明藻类和细菌在有毒污染物的转化和生态效应中存在密切关系。
