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Understanding the interaction between heavy metals and soil microbiomes is essential for maintaining ecosystem health and functionality in the face of persistent human-induced challenges. This study investigated the complex relationships between heavy metal contamination and the functional characteristics of soil microbial communities in the tidal soils of Hangzhou Bay, a region experiencing substantial environmental pressure due to its proximity to densely populated and industrialized regions. The north-shore sampling site showed moderate contaminations (mg/kg) of total arsenic (16.61 ± 1.13), cadmium (0.3 ± 0.05), copper (31.28 ± 1.23), nickel (37.44 ± 2.74), lead (34.29 ± 5.99), and zinc (120.8 ± 5.96), which are 1.29-2.94 times higher than the geochemical background values in Hangzhou Bay and adjacent areas. In contrast, the south-shore sampling site showed slightly higher levels of total arsenic (13.76 ± 1.35) and cadmium (0.13 ± 0.02) than the background values. Utilizing metagenomic sequencing, we decoded microbial functional genes essential for nitrogen, phosphorus, sulfur, and methane biogeochemical cycles. Although soil available nickel content was relatively low at 1 mg/kg, it exhibited strong associations with diverse microbial genes and biogeochemical pathways. Four key genes-hxlB, glpX, opd, and phny-emerged as pivotal players in the interactions with available nickel, suggesting the adaptability of microbial metabolic responses to heavy metal. Additionally, microbial genera such as Gemmatimonas and Ilumatobacter, which harbored diverse functional genes, demonstrated potential interactions with soil nickel. These findings highlight the importance of understanding heavy metal-soil microbiome dynamics for effective environmental management strategies in the tidal soils of Hangzhou Bay, with the goal of preserving ecosystem health and functionality amidst ongoing anthropogenic challenges.

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INTRODUCTION: Gene exchange between viruses and hosts plays an important role in driving virus-host coevolution, enabling adaptation of both viruses and hosts to environmental changes. However, the mechanisms and functional significance of virus-host gene exchanges over long-term scales remain largely unexplored. OBJECTIVE: The present study aimed to gain insights into the role of viruses in virus-host interactions and coevolution by monitoring virome dynamics along a millennium-long land reclamation chronosequence. METHODS: We collected 24 soil samples from 8 stages of a millennium-long land reclamation chronosequence, including non-reclamation, and reclamation periods of 10, 50, 100, 300, 500, 700, and 1000 years. We characterized their metagenomes, and identified DNA viruses within these metagenomes. RESULTS: Our findings reveal a significant shift in viral community composition after 50 years of land reclamation, but soil viral diversity reached a stable phase approximately 300 years after the initial reclamation. Analysis of the virus-host network showed a scale-free degree distribution and a reduction in complexity over time, with generalist viruses emerging as key facilitators of horizontal gene transfer. CONCLUSION: These findings highlight the integral role of viruses, especially generalist types, in mediating gene exchanges between viruses and hosts, thereby influencing the coevolutionary dynamics in soil ecosystems over significant timescales. This study offers novel insights into long-term virus-host interactions, showing how the virome responds to environmental changes, driving shifts in various microbial functions in reclaimed land.

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Selective catalytic oxidation of the hazardous DMF exhaust gas presents a significant challenge in balancing oxidation activity and products selectivity (CO, NOx, N2, etc.). It is found that Cu/H-MOR demonstrates superior performance for DMF oxidation compared to CuO on other supports (γ-Al2O3, HY, ZSM-5) in terms of product selectivity and stability. The geometric and electronic structures of CuO active sites in Cu/H-MOR have been regulated by CeO2 promoter, leading to an increase in the ratio of active CuO (highly dispersed CuO and Cu+ specie). As a result, the oxidation activity and stability of the Cu/H-MOR catalyst were enhanced for DMF selective catalytic oxidation. However, excessive CuO or CeO2 content led to decreased N2 selectivity due to over-high oxidation activity. It is also revealed that Ce3+ species, active CuO species, and surface acid sites play a critical role in internal selective catalytic reduction reaction during DMF oxidation. The 10Cu-Ce/H-MOR (1/4) catalyst exhibited both high oxidation activity and internal selective catalytic reduction activity due to its abundance of active CuO specie as well as Ce3+ species and surface acid sites. Consequently, the 10Cu-Ce/H-MOR (1/4) catalyst demonstrated the widest temperature window for DMF oxidation with high N2 selectivity. These findings emphasize the importance of surface active sites modification for DMF selective catalytic oxidation.

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Two new antimycin antibiotics; that is antimycins A(19) (1) and A(20) (2), were isolated from a cultured broth of marine actinomycete Streptomyces antibioticus H74-18 together with antimycins A(1a) (3a) and A(1b) (3b), A(2a) (4), A(3a) (5a) and A(3b) (5b). Their structures were determined by spectroscopic methods in combination with X-ray diffraction. Antimycin A(19) possessed a chiral acyl chain and an alkyl branch. The absolute configuration of chiral acyl chain in 1 was determined by X-ray diffraction analysis. Antimycin A(20) (2) has the shortest and simplest acetoxy acyl chain in the antimycins family. All the antimycins (1-5) showed potential antifungal activities against Candida albicans with MIC of about 5-10 µg ml(-1).