Fischerella thermalis transcripts from El Tatio hot springs metatranscriptomes

The cyanobacterium Fischerella thermalis is one of the main primary producers in the temperature gradient up to temperatures close to 60 C in terrestrial hot springs worldwide, but the mechanisms by which it maintains its photosynthetic activity at these high temperatures are not known. We have used molecular and bioinformatics approaches, in addition to photophysiological analyses, to determine the genetic activity related to the energy metabolism of F. thermalis in situ. The transcriptional activity and metabolic characteristics of F. thermalis measured by metatranscriptomics further suggest that carbon metabolism functions in parallel, connected to photosynthesis, being able to assist in obtaining energy at high temperatures where other photosynthetic organisms cannot survive. This study revealed that F. thermalis uses several compensatory adaptations to cope with the harsh conditions of hot springs.热生费氏蓝细菌（Fischerella thermalis）是全球陆地温泉中温度梯度高达近60℃环境下的主要初级生产者之一，但其在这类高温环境下维持光合活性的分子机制尚未明晰。本研究结合光生理分析手段，采用分子生物学与生物信息学方法，原位解析了热生费氏蓝细菌与能量代谢相关的遗传活性。通过宏转录组学（metatranscriptomics）检测得到的热生费氏蓝细菌转录活性与代谢特征进一步表明，其碳代谢通路与光合作用协同联动、紧密耦合，可在其他光合生物无法存活的高温环境中辅助获取能量。本研究揭示，热生费氏蓝细菌通过多种补偿性适应策略以应对温泉的极端环境。