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Sanchez-Cano, A.

Publications and source records attributed to Sanchez-Cano, A..

3 recordsLinked to original sources

A bifidobacterial enzyme orchestrates ecology and function of infant gut bacterial community

Human milk oligosaccharides (HMOs) are abundant and structurally diverse glycans that shape the development of infant gut microbiota. Yet, how individual HMOs and bacterial genes drive the community assembly remain elusive. Here, we reconstructed an eight-member infant Bacterial Community (iBaCo) from representing dominant taxa in human infant feces. When individual HMOs were the sole carbohydrate source, they showed deterministic effects on the iBaCo composition and metabolic output. Notably, the tetramer HMO lacto-N-tetraose (LNT), in spite of its identical monomer composition as lacto-N-neotetraose (LNnT), showed a strong effect on maintaining Bifidobacterium breve abundance in iBaCo, whereas LNnT did not. Monoculture growth profiling, proteomics, enzymatic kinetic assay, and molecular docking revealed that {beta}-galactosidase D4BMY8 and the relevant downstream pathways are induced by LNT and that D4BMY8 has substrate preference on LNT over LNnT, enabling a faster growth of Bi. breve and accumulation of acetate and lactate in LNT compared to LNnT. Metabolic flux analysis indicated that the substrate-preference of {beta}-galactosidase D4BMY8 drives the skewed energy cost toward lactate/acetate metabolic output. Finally, the D4BMY8-encoding gene lacZ5 is widely spread in all isolated Bi. breve genomes, but divergently distributed in infant metagenome-assembled Bi. breve genomes. Together, we demonstrated that a single enzyme-substrate interaction could orchestrate the composition and metabolic function of an infant bacterial community, which may contribute to the assembly of dynamic infant gut microbiota. Our integrative approach provides a mechanistic framework for understanding the interaction between diet, microbial community, and infant gut health.

microbiology↗

Real-time genomic pathogen, resistance, and host range characterization from passive water sampling of wetland ecosystems

Wetland ecosystems provide interfaces for the transmission of microbial pathogens and antimicrobial resistances (AMR) between migratory birds, wild and domestic animals, and human populations. The efficient surveillance of wetlands is, however, challenging, since the typically low concentration of pathogens typically requires the sampling of large volumes of water and subsequent targeted detection, which is inherently limited to a few pathogens or AMR genes of interest. Here, we present a holistic, accessible, and cost-efficient framework to characterize the pathogen and resistance load of water sources together with their potential associated hosts by combining passive water sampling through torpedo-shaped devices with nanopore sequencing technology. We used this framework to characterize anthropogenically influenced and natural wetland ecosystems along the East Atlantic Flyway, where we obtained robust assessments of the microbial communities from long-read metagenomic and RNA virome data, and showed that anthropogenically impacted wetland ecosystems consistently exhibited higher relative abundances of pathogens and AMR genes. By focusing on avian influenza viruses (AIV), we finally highlight the additional need for targeted screening and whole-genome sequencing of pathogens of interest; we detected and characterized AIV at a third of the monitored sites, and used environmental DNA (eDNA) to explore potential animal hosts to better understand the role of wetland ecosystems as One Health interfaces. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=191 HEIGHT=200 SRC="FIGDIR/small/674394v1_ufig1.gif" ALT="Figure 1"> View larger version (50K): org.highwire.dtl.DTLVardef@1a006f2org.highwire.dtl.DTLVardef@12824c2org.highwire.dtl.DTLVardef@8554bdorg.highwire.dtl.DTLVardef@17e800e_HPS_FORMAT_FIGEXP M_FIG C_FIG

microbiology↗

Bagaza virus in wild birds, Portugal, 2021

Bagaza virus (BAGV) emerged in Spain, in 2010. Since then, BAGV was not reported in other European countries until September 2021, when BAGV was diagnosed by molecular methods in one corn bunting and several red-legged partridges, after abnormal mortality in Southern Portugal. Sequencing revealed high similarity with strains reported previously.

pathology↗