The study of the composition and diversity of the wetland soil microbiota associated with hygrophilous plants in a desert ecosystem of the high Puna in northern Chile makes it an ideal approach to search for novel extremophilic microorganisms with unique properties. These microorganisms are adapted to survive in ecological niches, such as those with high UV irradiation, extreme drought, and high salt concentration; they can be applied in various fields, such as biotechnology and astrobiology, and industries, including the pharmaceutical, food, agricultural, biofuel, cosmetic, and textile industries.

Winemaking is a well-known process that includes several steps in the production of grape must and wine. Grape marc, or bagasse, is a byproduct of wine production that can be vermicomposted and used as organic fertilizer. Grape marc vermicompost has microbial communities that are richer and more stable than grape marc alone, and its addition to a vineyard’s terroir can improve grape yields and wine quality. Here we compare the must and wine microbiota of Mencía from grapevines treated with and without (standard fertilization) vermicompost derived from Mencía grape marc. Mencía is a high-quality red wine broadly grown in Galicia, Spain, and is appreciated for its fresh acidity and fruity flavors. When Mencía grapevines are treated with vermicompost derived from its grape marc, Mencía vines increase their grape production, and the final wine improves its organoleptic properties. Metataxonomic analyses of the bacterial 16S rRNA and fungal ITS gene regions showed that Mencía must and wine have the distinct taxonomic composition (phyla, genera and ASVs—amplicon sequence variants) of bacterial and fungal groups. Must and wine bacteriotas and mycobiotas show no significant variation in alpha-diversity, while wine bacteriotas and mycobiotas show significant differences in microbial structure (beta-diversity) between treated and control grapevines. Likewise, the functional diversity and predicted metabolic pathways (biosynthesis, degradation/utilization/assimilation, generation of precursor metabolites and energy, macromolecule modification and superpathways) of the must and wine microbiota also show significant changes. Our study proposes that changes in the abundance of microbial taxa and the metabolic processes they undergo during winemaking may improve Mencía’s organoleptic properties and productivity.

In this study, we analyzed the persistence of the water column through satellite images and physicochemical characterization to investigate the composition and diversity in High Andean Lake Systems in a hyperarid environment. In addition to the persistence of the water column, this approach can be used to analyze changes in the morphology of saline accumulations and persistence of snow or ice; for example, for establishing variable plant cover over time and evaluating the microbiota associated with soils with seasonal changes in plants.

Moraxella catarrhalis is an opportunistic pathogen of the human respiratory tract, primarily associated with otitis media in children and exacerbations of chronic obstructive pulmonary disease in adults. Despite its clinical importance, the genomic diversity and functional specialization of M. catarrhalis remain insufficiently characterized. This study aimed to analyse the global genetic diversity of M. catarrhalis using whole-genome sequencing to identify phylogenetic lineages, antimicrobial resistance patterns and key virulence factors. Phylogenomic analysis of 345 publicly available genomes identified 3 phylogroups, of which 1 exhibited significant genomic divergence and was excluded from further analyses due to its potential classification as a separate species. The remaining two phylogroups corresponded to previously described seroresistant and serosensitive lineages. Phylogroup B exhibited a higher prevalence of antimicrobial resistance genes, particularly bro-1 and bro-2, while phylogroup A exhibited unique metabolic adaptation, including genes encoding for the DppB-DppC-DppD dipeptide transport system. Both phylogroups shared crucial virulence factors, including UspA1 and UspA2, which facilitate adhesion and immune evasion. Potential therapeutic targets were identified, including PilQ, essential for type IV pilus biogenesis, and CopB, which plays a key role in iron acquisition and immune evasion. Overall, these findings highlight the significance of phylogenomics approaches in elucidating the genetic mechanisms underlying pathogenicity and resistance in M. catarrhalis, providing insights for future therapeutic and preventive strategies.

Las comunidades microbianas son esenciales para la productividad de los agroecosistemas. En caña de azúcar, el uso de fertilizantes nitrogenados, como práctica de manejo común, mantiene los niveles de la productividad del cultivo e influye en la diversificación del microbioma, ocasionando cambios en la diversidad de los microorganismos involucrados en el ciclo del nitrógeno (N). El objetivo de este estudio consistió en analizar la influencia de diferentes regímenes de fertilización nitrogenada sobre la estructura y la composición de la comunidad microbiana rizosférica, en un experimento de larga duración. Esta investigación permitirá establecer un régimen de fertilización más preciso. Se demostró que no existen diferencias significativas en la composición y en la estructura de la comunidad bacteriana, al usar diferentes niveles de fertilización nitrogenada en caña de azúcar. Los Phylum Acidobacteria, Firmicutes y Mortierellomycota fueron los más relacionados con las dosis de nitrógeno recomendadas, para obtener altos rendimientos agrícolas, bajo las condiciones de Cuba; sin embargo, existieron variaciones en cuanto a composición y abundancias relativas de los Phylum de la micobiota respecto a las dosis de nitrógeno aplicadas, con predominio de los Phylum Ascomycota y Basidiomycota. Fueron detectadas diferencias significativas, a nivel de género y familia, debido a la presencia de organismos probióticos en las parcelas no tratadas.

The work of Demergasso et al: " The Limits of Life at Extremely Low Water Activity: Lithium-Concentration Ponds in a Solar Saltern (Salar de Atacama, Chile)" evaluates how far along the salinity gradient life could be found, using a chemical, molecul...