The pivotal role of the native bacterial community in maintaining soil health, particularly in degraded tailings environments, is often overlooked. This study utilized peat, rich in microorganisms, to investigate its impact on soil function and native bacteria response in copper tailings-soil. Through 16S rRNA gene sequencing, changes in nutrient cycling, organic matter decomposition, and microbial activity were assessed post one-year peat remediation. Results from FEAST and cluster analysis revealed that peat-derived species disproportionately influenced tailings microbial community remediation, supported by the microbial invasion theory. Tailings responded positively to these species, with optimal function achieved at 5 % peat dosage. Peat biomarkers (Actinobacteriota, Bacteroida, Chloroflexi, and Firmicutes) played key roles in heavy metal removal and nutrition fixation. The Random Forest model and co-occurrence network highlighted contributions from native rare species (Dependentiae and Latescibacterota) activated by peat addition. These insights underscore the resilience of rare taxa and provide a foundation for soil health restoration in tailings areas. By emphasizing the importance of peat as a potential exogenous solution for activating indigenous microbial functions, these findings offer valuable insights for developing effective and sustainable remediation strategies in mining-affected regions.

Lipopolysaccharide (LPS) is essential for most gram-negative bacteria and plays an important role in serum resistance, pathogenesis, drug resistance, and protection from harsh environments. The outer core oligosaccharide of LPS is involved in bacterial recognition and invasion of host cells. The D-galactosyltransferase WaaB is responsible for the addition of D-galactose to the outer core oligosaccharide of LPS, which is essential for Salmonella typhimurium invasion. Here we report the first crystal structures of WaaB and WaaB in complex with UDP to resolutions of 1.8 and 1.9 Å, respectively. Mutagenesis and enzyme activity assays confirmed that residues V186, K195, I216, W243, E276, and E269 of WaaB are essential for the binding and hydrolysis of UDP-galactose. The elucidation of the catalytic mechanism of WaaB is of great importance and could potentially be used for the design of novel therapeutic reagents.

Intensive management has greatly altered natural forests, especially forests around the world are increasingly being converted into economic plantations. Soil microbiota are critical for community functions in all ecosystems, but the effects of microbial disturbance during economic plantation remain unclear. Here, we used Escherichia coli O157:H7, a model pathogenic species for bacterial invasion, to assess the invasion impacts on the soil microbial community under intensive management. The E. coli invasion was tracked for 135 days to explore the instant and legacy impacts on the resident community. Our results showed that bamboo economic plantations altered soil abiotic and biotic properties, especially increasing pH and community diversity. Higher pH in bamboo soils resulted in longer pathogen survivals than in natural hardwood soils, indicating that pathogen suppression during intensive management should arouse our attention. A longer invasion legacy effect on the resident community (P < 0.05) were found in bamboo soils underlines the need to quantify the soil resilience even when the invasion was unsuccessful. Deterministic processes drove community assembly in bamboo plantations, and this selection acted more strongly during by E. coli invasion than in hardwood soils. We also showed more associated co-occurrence patterns in bamboo plantations, suggesting more complex potential interactions within the microbial community. Apart from community structure, community functions are also strongly related to the resident species associated with invaders. These findings provide new perspectives to understand intensive management facilitates the bacterial invasion, and the impacts would leave potential risks on environmental and human health.

Bacterial infection is a major threat to human health, with infections resulting in considerable mortality, urging the need for a more profound understanding of bacteria-host interactions. During infection of cells, host cytoskeletal networks constantly interact with bacteria and are integral to their uptake. Vimentin, an intermediate filament protein, is one such cytoskeletal component that interacts with bacteria during infection. Although vimentin is predominantly present in the cytoplasm, it also appears in a secreted form or at the surface of multiple cell types, including epithelial cells, endothelial cells, macrophages and fibroblasts. As a cytoplasmic protein, vimentin participates in bacterial transportation and the consequential immune-inflammatory responses. When expressed on the cell surface, vimentin can be both pro- and anti-bacterial, favoring bacterial invasion in some contexts, but also limiting bacterial survival in others. Vimentin is also secreted and located extracellularly, where it is primarily involved in bacterial-induced inflammation regulation. Reciprocally, bacteria can also manipulate the fate of vimentin in host cells. Given that vimentin is not only involved in bacterial infection, but also the associated life-threatening inflammation, the use of vimentin-targeted drugs might offer a synergistic advantage. In this Review, we recapitulate the abundant evidence on vimentin and its dynamic changes in bacterial infection and speculate on its potential as an anti-bacterial therapeutic target.

As an inflammatory cytokine of the interleukin-20 (IL-20) subfamily, IL-20 has various functions in immune defenses, inflammatory diseases, tissue regeneration, cancer, and metabolism. Although the characteristics and functions of mammalian IL-20 have been clarified, those of fish IL-20 remain unclear. In this study, the IL-20 gene from the snakehead Channa argus (shIL-20) was cloned and functionally characterized. Similar to the IL-20 homologues of other species, the shIL-20 has a five exon/four intron structure in the coding region. The open reading frame of shIL-20 consists of 528 base pairs and encodes 175 amino acids (aa), including a signal peptide (aa 1-24) and a mature peptide (aa 25-175). The mature shIL-20 protein has six conserved cysteine residues, which occur in the IL-20 proteins of all species analyzed, and an additional cysteine residue (Cys-82) found only in the IL-20 proteins of several teleosts. The modeled tertiary structure of shIL-20 is similar with that of Homo sapiens IL-20. The shIL-20 was expressed constitutively in all the tissues analyzed, and its transcription was induced in the spleen and head kidney by Aeromonas schubertii and Nocardia seriolae in vivo and in head kidney leukocytes (HKLs) by lipoteichoic acid, lipopolysaccharide, and polyinosinic-polycytidylic acid in vitro. The recombinant shIL-20 protein induced the transcription of tumor necrosis factor α1 (TNF-α1), TNF-α2, IL-1β, and endogenous shIL-20, and promoted the proliferation of HKLs. In conclusion, these findings demonstrate that shIL-20 participates in the immune response to bacterial invasion and promotes leukocyte proliferation, offering new insights into the functions of fish IL-20 during pathogen invasion.