Departamento de Ecología Evolutiva, Instituto de Ecología, Universidad Nacional Autónoma de México, Ciudad de México, México.
Doctorado en Ciencias Biomédicas, Universidad Nacional Autónoma de México, Ciudad de México, México.
Microb Genom. 2023 Jul;9(7). doi: 10.1099/mgen.0.001063.
In spring 2016, a shallow hypersaline pond (50×25 m) was found in the Cuatro Cienegas Basin (CCB). This pond, known as Archaean Domes (AD) because of its elastic microbial mats that form dome-shaped structures due to the production of reducing gases reminiscent of the Archaean eon, such as methane and hydrogen sulfide, harbour a highly diverse microbial community, rich in halophilic and methanogenic archaea. AD is a seasonally fluctuating hypersaline site, with salinity ranging from low hypersaline (5.3%) during the wet season to high hypersaline (saturation) during the dry season. To characterize the viral community and to test whether it resembles those of other hypersaline sites (whose diversity is conditioned by salinity), or if it is similar to other CCB sites (with which it shares a common geological history), we generated 12 metagenomes from different seasons and depths over a 4 year period and compared them to 35 metagenomes from varied environments. Haloarchaeaviruses were detected, but were never dominant (average of 15.37 % of the total viral species), and the viral community structure and diversity were not affected by environmental fluctuations. In fact, unlike other viral communities at hypersaline sites, AD remained more diverse than other environments regardless of season. β-Diversity analyses show that AD is closely related to other CCB sites, although it has a unique viral community that forms a cluster of its own. The similarity of two surface samples to the 30 and 50 cm depth samples, as well as the observed increase in diversity at greater depths, supports the hypothesis that the diversity of CCB has evolved as a result of a long time environmental stability of a deep aquifer that functions as a 'seed bank' of great microbial diversity that is transported to the surface by sporadic groundwater upwelling events.
2016 年春，在四泉古盆地（CCB）发现了一个浅的高盐池塘（50×25m）。由于其弹性微生物席形成了穹顶状结构，这些微生物席由于产生了类似于太古代的还原气体，如甲烷和硫化氢，因此被称为太古穹顶（AD）。AD 拥有高度多样化的微生物群落，富含嗜盐菌和产甲烷古菌。AD 是一个季节性波动的高盐地点，盐度在雨季时低至高盐（5.3%），在旱季时则达到高盐饱和。为了描述病毒群落并测试其是否类似于其他高盐地点（其多样性受盐度条件限制），或者是否与具有共同地质历史的其他 CCB 地点相似，我们在 4 年的时间里从不同季节和深度生成了 12 个宏基因组，并将其与 35 个来自不同环境的宏基因组进行了比较。检测到了 Haloarchaeaviruses，但它们从未占主导地位（平均占总病毒种类的 15.37%），病毒群落结构和多样性不受环境波动的影响。事实上，与其他高盐地点的病毒群落不同，AD 始终保持比其他环境更高的多样性。β多样性分析表明，AD 与其他 CCB 地点密切相关，尽管它具有独特的病毒群落，形成了自己的聚类。两个表面样本与 30 和 50cm 深度样本的相似性，以及在更深的深度观察到的多样性增加，支持了这样一种假设，即 CCB 的多样性是由于深层含水层的长时间环境稳定而进化而来的，深层含水层作为一个具有巨大微生物多样性的“种子库”，通过间歇性的地下水上升事件被输送到地表。
