Doctorado en Ciencias Biológicas y de La Salud, Universidad Autónoma Metropolitana, Mexico City, Mexico.
Estructura, Dinámica y Función de Genomas de Rizobacterias, Departamento de Microbiología del Suelo y Sistemas Simbióticos, Estación Experimental del Zaidín-CSIC, Granada, Spain.
BMC Genomics. 2023 Nov 20;24(1):696. doi: 10.1186/s12864-023-09800-9.
Isabel Island is a Mexican volcanic island primarily composed of basaltic stones. It features a maar known as Laguna Fragatas, which is classified as a meromictic thalassohaline lake. The constant deposition of guano in this maar results in increased levels of phosphorus, nitrogen, and carbon. The aim of this study was to utilize high-quality genomes from the genus Halomonas found in specialized databases as a reference for genome mining of moderately halophilic bacteria isolated from Laguna Fragatas. This research involved genomic comparisons employing phylogenetic, pangenomic, and metabolic-inference approaches.
The Halomonas genus exhibited a large open pangenome, but several genes associated with salt metabolism and homeostatic regulation (ectABC and betABC), nitrogen intake through nitrate and nitrite transporters (nasA, and narGI), and phosphorus uptake (pstABCS) were shared among the Halomonas isolates.
The isolated bacteria demonstrate consistent adaptation to high salt concentrations, and their nitrogen and phosphorus uptake mechanisms are highly optimized. This optimization is expected in an extremophile environment characterized by minimal disturbances or abrupt seasonal variations. The primary significance of this study lies in the dearth of genomic information available for this saline and low-disturbance environment. This makes it important for ecosystem conservation and enabling an exploration of its biotechnological potential. Additionally, the study presents the first two draft genomes of H. janggokensis.
伊莎贝尔岛是一个主要由玄武岩石组成的墨西哥火山岛。它以一个名为 Laguna Fragatas 的火山口湖为特色，被归类为分层的盐水微咸湖。在这个火山口湖中，鸟粪的不断沉积导致磷、氮和碳的含量增加。本研究的目的是利用专门数据库中发现的嗜盐菌属 Halomonas 的高质量基因组作为 Laguna Fragatas 中分离出的中度嗜盐细菌的基因组挖掘的参考。这项研究涉及使用系统发育、泛基因组和代谢推断方法进行基因组比较。
Halomonas 属表现出一个大型的开放泛基因组，但与盐代谢和体内平衡调节相关的几个基因（ectABC 和 betABC）、通过硝酸盐和亚硝酸盐转运体摄入氮（nasA 和 narGI）以及磷吸收（pstABCS）在 Halomonas 分离株中共享。
分离出的细菌表现出对高盐浓度的一致适应，其氮和磷吸收机制高度优化。在干扰最小或季节变化突然的极端环境中，这种优化是预期的。这项研究的主要意义在于，这种高盐和低干扰环境的基因组信息非常有限。这对于生态系统保护和探索其生物技术潜力非常重要。此外，该研究还提供了两种 H. janggokensis 的首个草案基因组。
