Deforestation impacts network co-occurrence patterns of microbial communities in Amazon soils.

Co-occurrence networks allow for the identification of potential associations among species, which may be important for understanding community assembly and ecosystem functions. We employed this strategy to examine prokaryotic co-occurrence patterns in the Amazon soils and the response of these patterns to land use change to pasture, with the hypothesis that altered microbial composition due to deforestation will mirror the co-occurrence patterns across prokaryotic taxa. In this study, we calculated Spearman correlations between operational taxonomic units (OTUs) as determined by 16S rRNA gene sequencing, and only robust correlations were considered for network construction (-0.80 ≥ P ≥ 0.80, adjusted P < 0.01). The constructed network represents distinct forest and pasture components, with altered compositional and topological features. A comparative analysis between two representative modules of these contrasting ecosystems revealed novel information regarding changes to metabolic pathways related to nitrogen cycling. Our results showed that soil physicochemical properties such as temperature, C/N and H++Al3+ had a significant impact on prokaryotic communities, with alterations to network topologies. Taken together, changes in co-occurrence patterns and physicochemical properties may contribute to ecosystem processes including nitrification and denitrification, two important biogeochemical processes occurring in tropical forest systems

In vitro fabrication of microscale secretory granules

Advanced medical treatments involving drug delivery require fully biocompatible materials with the ability to release functional drugs in a time-prolonged way. Ideally, the delivered molecules should be self-contained as chemically homogenous entities to prevent the use of potentially toxic scaffolds or hold matrices. In nature, peptidic hormones are self-stored in protein-only secretory granules formed by the reversible coordination of Zn2+ and histidine residues. Inspired by this concept, an in vitro transversal procedure is developed, analyzed, and comparatively applied for the fabrication of protein-only secretory granules at the microscale. These materials can be produced from any polyhistidine-tagged protein using physiological concentrations of Zn2+ as a potent and versatile glue-like agent. The screening of granules formed by 12 engineered and nonengineered proteins at different Zn2+ concentrations revealed optimal fabrication conditions and the consequent release profiles. Moreover, the functional and structural properties of the delivered protein are fully validated using a drug-targeting protein platform in a mouse model of human colorectal cancer. In summary, short histidine tags allow the packaging of structurally and functionally dissimilar polypeptides, which supports the proposed fabrication method as a powerful protocol extensible to diverse clinical scenarios in which slow protein drug delivery is required.Fil: Hector Lopez Laguna. Universitat Autònoma de Barcelona; EspañaFil: Eloi Parlade. Universitat Autònoma de Barcelona; EspañaFil: Patricia Álamo,. Hospital de la Santa Creu I Sant Pau; EspañaFil: Sanchez, Julieta Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Biológicas y Tecnológicas. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Investigaciones Biológicas y Tecnológicas; ArgentinaFil: Eric Volta Duran. Universitat Autònoma de Barcelona; EspañaFil: Naroa Serna. Universitat Autònoma de Barcelona; EspañaFil: Laura Sánchez-Garcia. Universitat Autònoma de Barcelona; EspañaFil: Olivia Cano-Garrido. Universitat Autònoma de Barcelona; España. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Biológicas y Tecnológicas. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Investigaciones Biológicas y Tecnológicas; ArgentinaFil: Alejandro Sánchez-Chardi. Universitat Autònoma de Barcelona; EspañaFil: Antonio Villaverde. Universitat Autònoma de Barcelona; EspañaFil: Ramon Mangues. Hospital de la Santa Creu I Sant Pau; EspañaFil: Ugutz Unzueta. Hospital de la Santa Creu I Sant Pau; EspañaFil: Esther Vázquez. Universitat Autònoma de Barcelona; Españ