Carbohydrate-active enzymes of soil prophages enhance global carbon cycling potential

Metagenomic Analysis of Soil Microbial Community Shifts Formed by 60-Day Exposure to Polylactic Acid Microplastics

Soil microbial community dynamics are closely linked to ecosystem functions and responses to environmental stress. This study aimed to investigate the impacts of incubation time and different treatment conditions (CK, CK60, and PLA60) on soil bacterial community structure, diversity, and potential metabolic functions. A 60-day microcosm incubation experiment was conducted, comprising polylactic acid (PLA)-amended soil and blank controls. Metagenomic sequencing revealed that PLA exposure significantly altered both the structure and function of the soil microbial community. Over time, the Pseudomonadota phylum became significantly enriched, and the genus Sphingomonas emerged as the dominant genus. Alpha-diversity (Shannon index) decreased in PLA-treated soils, while beta-diversity (PCA) demonstrated distinct separation among treatment groups.Functional predictions indicate that PLA processing drives functional remodeling of the microbial community to adapt to environmental stress by synergistically activating core energy metabolic pathways such as bacterial glycolysis and the tricarboxylic acid cycle. The time effect and PLA treatment jointly drove the restructuring of the soil bacterial community.

Identification of key carbon-fixation pathways and underlying genes for higher CO2 fixation of mangrove-associated microalgae

Metagenomic insights into potential PET hydrolases from Antarctic soils and rhizospheres

A metagenomic analysis of soil and rhizosphere samples from the Antarctic vascular plants Deschampsia antarctica and Colobanthus quitensis is conducted, as sources of microbial enzymes with potential PET-hydrolytic activity, demonstrating the diversity of PET-hydrolase-like genes within Antarctic rhizosphere and soil microbiomes.

Ethylene Affects Soil Multifunctionality in Maize Rhizosphere by Driving Sensitive Microbial Communities

Ethylene modulates plant fitness, but its role in rhizosphere soil multifunctionality remains unclear. This study demonstrates that endogenous ethylene suppresses C- and N-cycling functions while promoting organic P mineralization in the maize rhizosphere, ultimately diminishing the overall soil multifunctionality and attenuating its phenologically driven peak at the tasseling stage. Ethylene reshaped microbial community assembly by enriching opportunistic taxa (e.g., Actinobacteria) while reducing the diversity and relative abundance of sensitive taxa. Community composition (e.g., Bacillus) and α diversity of ethylene-sensitive taxa were negatively correlated with soil multifunctionality. Inoculation with ACC deaminase-producing Bacillus pumilus and Streptomyces gardneri (opportunistic strains) significantly elevated C- and N-cycling enzyme activities and boosted maize growth. However, a direct causal link between ACC deaminase production and these effects requires further experimental validation. Collectively, these findings elucidate that ethylene drives rhizosphere biogeochemical trade-offs through the selective filtering of microbial functional guilds, providing a theoretical foundation for rhizosphere microbiome management in crop production.

A rhizarian genome reveals an osmotrophic route to extracellular digestion in eukaryotes

It is demonstrated that osmotrophic saprotrophy has evolved independently in Rhizaria with enzymatic solutions that closely parallel those of evolutionary distant fungal decomposers, highlighting the power of ecological context over phylogenetic heritage in shaping extracellular metabolic architecture.

Genome-centric analysis reveals the importance of granular activated carbon on quorum sensing and glucose metabolism in anaerobic digestion.

Granular activated carbon (GAC) enhances anaerobic digestion (AD) performance, potentially via biofilm promotion, microbial enrichment, and facilitating direct interspecies electron transfer (DIET). In this work, to investigate the role of GAC, DNA was extracted from sludge in lab-scale digesters (with/without GAC) and GAC biofilm. Genome-resolved analysis revealed GAC established distinct niches enriching Methanothrix and Methanosarcina vacuolata. DIET potential would be indicated by strictly filtered pilA genes with the presence of aromatic amino acids, but not the overall pilA genes. While capable of DIET, Methanothrix primarily utilized the acetoclastic pathway. Methanosarcina vacuolata actively partnered with electroactive bacteria, likely via conductive pili. Enhanced performance with GAC primarily stemmed from increased glucose transport activity and microbial enrichment, not DIET. Mature biofilms during prolonged operation may amplify DIET contributions. Thus, the immediate value of GAC lies in optimizing substrate metabolism and spatial community structuring, with biofilm maturation potentially unlocking greater DIET-mediated efficiency.