Deciphering the functional potential of a hypersaline marsh microbial mat community

The present study combines 16S rRNA amplicon sequencing and metagenomic approaches to characterize microbial structure and functional potential of the sediment and microbial mats of a hypersaline marsh in Tristomo bay (Karpathos, Greece) which is under protection from national legislation and international treaties. Sampling was conducted in July of 2018 and November of 2019. Sediment samples were collected from the sediment's upper layer (0-1 cm: microbial mats, 1-3 cm: deeper sediment) at various sampling sites using cylindrical cores and were frozen at -20 oC upon return to the laboratory. In addition, microbial aggregates observed in the water overlaying the sediment were collected separately based on their color (orange or pink). Furthermore, environmental parameters (e.g. salinity, oxygen concentration, granulometric composition) were measured at the sampling sites. The construction of metagenomic libraries from sediment samples, microbial mats and microbial aggregates of the hypersaline swamp allowed the description of the whole microbial community in the study area and revealed its functional potential.

本研究结合16S rRNA扩增子测序（16S rRNA amplicon sequencing）与宏基因组方法（metagenomic approaches），对位于希腊卡尔帕索斯岛（Karpathos）特里斯托莫湾（Tristomo bay）、受国家立法及国际条约保护的一处高盐沼泽的沉积物与微生物垫的微生物群落结构及功能潜力进行表征。采样工作于2018年7月及2019年11月开展。采用圆柱形岩芯在多个采样点采集沉积物样品，分别获取沉积物上层（0~1 cm层为微生物垫，1~3 cm层为深层沉积物），带回实验室后即刻置于-20℃条件下冷冻保存。此外，针对沉积物上覆水体中观测到的微生物聚集体，依据其颜色（橙色或粉色）分别进行采集。同时，在各采样点测定了盐度、氧浓度、粒度组成等环境参数。通过构建该高盐沼泽沉积物、微生物垫及微生物聚集体的宏基因组文库（metagenomic libraries），本研究得以解析研究区域内完整的微生物群落组成，并揭示其功能潜力。