Divergent metabolic and transcriptomic responses of Synechocystis sp. PCC 6803 to salt stress after adaptive laboratory evolution
Divergent metabolic and transcriptomic responses of Synechocystis sp. PCC 6803 to salt stress after adaptive laboratory evolution
复制标题
集胞藻的不同代谢和转录组反应。
DOI：
10.1016/j.algal.2020.101856
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发表时间：
2020-05-01
影响因子：
5.1
通讯作者：
Wang, Jiangxin
中科院分区：
文献类型：
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作者：
Hu, Lang;He, Jiayi;Wang, Jiangxin
微藻具有许多优势，使其成为生产有价值产品的很好的潜在生物反应器。然而，微藻养殖消耗大量淡水，并与农作物竞争。这些缺点可以通过在海水中培养微藻来避免。适应性实验室进化(ALE)是指实验种群在设计条件下的进化。本研究以3%氯化钠为选择压力，对聚球藻的10个独立种群进行了长期的ALE实验。PCC 6803。经过303天的盐胁迫，获得了8株耐盐性提高的ALE菌株。对这些产生ALE的菌株进行了基于气相色谱-质谱仪(GC-MS)的代谢谱分析，发现盐胁迫诱导的相容溶质包括葡萄糖甘油和蔗糖。基于代谢组学的系统聚类分析表明，在正常条件下，这些ALE产生的菌株具有相似的代谢物组成，而在盐胁迫后，它们分为两个亚群，每个亚群都有独特的代谢物组成。转录本分析表明，不同亚群的菌株具有不同的基因表达模式。在ALE产生的菌株之间发现的对盐胁迫的不同代谢和转录反应可能表明联孢子菌在盐胁迫下使用更好的对冲策略。本研究不仅提供了耐盐菌株，而且有助于更好地了解蓝藻在盐胁迫下的进化。
Microalgae have many advantages making this group a good potential bioreactor for valuable productions. However, microalgae cultivation consumes large amount of freshwater and competes with crops. These shortcomings can be avoided by cultivating microalgae in seawater. Adaptive laboratory evolution (ALE) refers to the evolution of experimental populations under designed conditions. In present study, a long term ALE experiment with 3% NaCl as the selective pressure was conducted on 10 independent populations of Synechocystis sp. PCC 6803. After 303 days of salt stress, 8 ALE-generated strains with improved salt tolerance were obtained. Gas chromatography and mass spectrometry (GC–MS) based metabolic profiling was conducted on these ALE-generated strains, revealing salt stress-induced compatible solutes such as glucosyl glycerol and sucrose. Hierarchical cluster analysis based on metabonomics indicated that under normal condition these ALE-generated strains shared a similar metabolite composition, while they fell into two subclusters after salt stress, each of which had a unique metabolite composition. Transcriptomic analysis showed that strains from different subclusters had different gene expression patterns. Divergent metabolic and transcriptomic responses to salt stress found among the ALE-generated strains may indicate the bet hedging strategy used bySynechocystisunder salt stress. This study not only provides salt-tolerant strains but also helps to better understand the evolution of cyanobacteria under salt stress.