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Microbial community function depends on both taxonomic composition and spatial organization. While composition of the human gut microbiome has been deeply characterized, less is known about the organization of microbes between regions such as lumen and mucosa and the microbial genes regulating this organization. Using a defined 117 strain community for which we generate high-quality genome assemblies, we model mucosa/lumen organization with in vitro cultures incorporating mucin hydrogel carriers as surfaces for bacterial attachment. Metagenomic tracking of carrier cultures reveals increased diversity and strain-specific spatial organization, with distinct strains enriched on carriers versus liquid supernatant, mirroring mucosa/lumen enrichment in vivo. A comprehensive search for microbial genes associated with this spatial organization identifies candidates with known adhesion-related functions, as well as novel links. These findings demonstrate that carrier cultures of defined communities effectively recapitulate fundamental aspects of gut spatial organization, enabling identification of key microbial strains and genes.

Recombination enables reciprocal exchange of genomic information between parental chromosomes and successful segregation of homologous chromosomes during meiosis. Errors in this process lead to negative health outcomes, whereas variability in recombination rate affects genome evolution. In mammals, most crossovers occur in hotspots defined by PRDM9 motifs, although PRDM9 binding peaks are not all equally hot. We hypothesize that dynamic patterns of meiotic genome folding are linked to recombination activity. We apply an integrative bioinformatics approach to analyze how three-dimensional (3D) chromosomal organization during meiosis relates to rates of double-strand-break (DSB) and crossover (CO) formation at PRDM9 binding peaks. We show that active, spatially accessible genomic regions during meiotic prophase are associated with DSB-favored loci, which further adopt a transient locally active configuration in early prophase. Conversely, crossover formation is depleted among DSBs in spatially accessible regions during meiotic prophase, particularly within gene bodies. We also find evidence that active chromatin regions have smaller average loop sizes in mammalian meiosis. Collectively, these findings establish that differences in chromatin architecture along chromosomal axes are associated with variable recombination activity. We propose an updated framework describing how 3D organization of brush-loop chromosomes during meiosis may modulate recombination.

Autophagy is recognized as a crucial regulatory process, instrumental in the removal of senescent, dysfunctional, and damaged cells. Within the autophagic process, lysosomal digestion plays a critical role in the elimination of impaired organelles, thus preserving fundamental cellular metabolic functions and various biological processes. Mitophagy, a targeted autophagic process that specifically focuses on mitochondria, is essential for sustaining cellular health and energy balance. Therefore, a deep comprehension of the operational mechanisms and implications of autophagy and mitophagy is vital for disease prevention and treatment. In this context, we examine the role of autophagy and mitophagy during hair follicle cycles, closely scrutinizing their potential association with hair loss. We also conduct a thorough review of the regulatory mechanisms behind autophagy and mitophagy, highlighting their interaction with hair follicle stem cells and dermal papilla cells. In conclusion, we investigate the potential of manipulating autophagy and mitophagy pathways to develop innovative therapeutic strategies for hair loss. [ABSTRACT FROM AUTHOR]

Summary: Oxygen is contributing to the deterioration of the beer and shortening the shelf‐life of the packaged product. The effect of dissolved oxygen (DO) on oxidative and structural characteristics of protein in beer during forced ageing was examined. Results showed that increased DO decreased obviously protein content in beer, and further reduced antioxidant activities of beer and lipid transfer protein 1 (LTP1). Meanwhile, the increase of DO decreased significantly the free thiol groups content and enhanced the disulfide bonds level in beer and LTP1. Results from circular dichroism, surface hydrophobicity and zeta‐potential illustrated that the increase of DO dramatically changed the secondary and tertiary structure of LTP1 with the decrease in the surface hydrophobicity, α‐helix and β‐turn contents, and the increase in the random coil and negative zeta potential. These results indicated that increased DO could damage the structure of LTP1 and had a negative impact on oxidative stability of beer. [ABSTRACT FROM AUTHOR]

Supplementation of lychee juice was made with concentration in the range 60 ~ 360 mg/L of ammonium chloride, diammonium phosphate, respectively, the effects on the fermentation dynamics of saccharomyces cerevisiae and (non) volatile constituents produced during the fermentation of lychee wine were investigated. The results showed that addition of different concentrations of ammonium chloride and diammonium phosphate increased the rate of consumption sugar at dUferent degrees, and shortened the yeast fermentation time. The alcohol content and total esters were increased significantly, whereas the glycerol, acetaldehyde and succinic acid was decreased obviously. A product of the Maillard reaction, 2,3-dihydro-3,5-dihydroxy-6-methyl-4H-Py-ran-4-one (DDMP), which has various physiological functions, was detected for the first time in lychee wine. It proved that the supplementation of inorganic nitrogen source promoted the generation of the product. [ABSTRACT FROM AUTHOR]

In this study, the quality of matured coconut water was improved through fermentation with Saccharomyces cerevisiae D254. During fermentation, the kinetic models of yeast growth, alcohol production, and sugar consumption were established based on logistic and Leudeking–Piret equations. Fructose, glucose, sucrose, total phenolic content, and antioxidant capacity (FRAP and ABTS values) were measured consecutively during fermentation. Results showed that R2 for the three models of yeast growth, alcohol production, and sugar consumption were 0.9772, 0.9983, and 0.9887, respectively. Total phenolic and antioxidant assays showed a similar evolution during fermentation, with a rapid increase in exponential phase and an unchanged trend in stationary phase. Moreover, total phenolic and the two antioxidant capacity methods were highly positively correlated. Pyruvic, lactic, citric, and succinic acids were the main organic acids in coconut water after fermentation. [ABSTRACT FROM AUTHOR]