Mobilome-mediated transcriptional activation of biosynthetic gene clusters and its impact on strain competitiveness in food fermentation microbiomes.

Background: Microbial interactions are critical for maintaining the stability of food fermentation microbiomes, and mobile genetic elements (MGEs) significantly influence these interactions by horizontal gene transfer events. Although MGEs are known to facilitate horizontal gene transfer, their distribution among microorganisms and specific effects on microbial interactions remain poorly understood.

Results: We analyzed 590 metagenomic and 42 metatranscriptomic samples from food fermentations, recovering 1133 metagenome-assembled genomes (MAGs).

Nitrogen fixation in Pampinifervens, a new species-rich genus of Aquificaceae that inhabits a wide pH range in terrestrial hot springs.

Members of the Aquificota play important roles in hydrogen, sulfur, and carbon cycles in geothermal systems as ubiquitous and abundant chemolithoautotrophs; however, their roles in the nitrogen cycle are poorly defined. Here, we show that Aquificaceae isolate T-2 from Tengchong, China, fixes nitrogen based on growth with dinitrogen as the sole nitrogen source and incorporation of N atoms when grown with N. We further show evidence that suggests its nitrogen fixation (nif) genes are transcribed in situ in a nearby spring.

Trujillonella humicola sp. nov., a siderophore-synthesizing bacterium isolated from black soil in Northeast China.

A Gram-stain-positive, motile, and oval-shaped bacterium, designated as SYSU BS000539, was isolated from black soil in Heilongjiang Province, China. 16S rRNA gene sequencing revealed that the isolate shared the highest similarity to Trujillonella endophytica DSM 45413 (98.32%), and phylogenetic analysis confirmed that it belonged to the genus Trujillonella.

Insights into chemoautotrophic traits of a prevalent bacterial phylum CSP1-3, herein .

Candidate bacterial phylum CSP1-3 has not been cultivated and is poorly understood. Here, we analyzed 112 CSP1-3 metagenome-assembled genomes and showed they are likely facultative anaerobes, with 3 of 5 families encoding autotrophy through the reductive glycine pathway (RGP), Wood-Ljungdahl pathway (WLP) or Calvin-Benson-Bassham (CBB), with hydrogen or sulfide as electron donors. Chemoautotrophic enrichments from hot spring sediments and fluorescence hybridization revealed enrichment of six CSP1-3 genera, and both transcribed genes and DNA-stable isotope probing were consistent with proposed chemoautotrophic metabolisms.

Parafrigoribacterium soli sp. nov. and Parafrigoribacterium humi sp. nov., two novel siderophore-synthesizing species isolated from black soil.

Two siderophore-synthesizing species SYSU BS000078 and SYSU BS000231 were isolated from the black soil collected from fields located in Heilongjiang province, China. The results of phylogenetic analysis based on the 16S rRNA gene sequences indicated that these two strains showed the highest sequence similarity to Parafrigoribacterium mesophilum KCTC 19311 (98.61 % and 98.

SALINITY-Induced Changes in Diversity, Stability, and Functional Profiles of Microbial Communities in Different Saline Lakes in Arid Areas.

Saline lakes, characterized by high salinity and limited nutrient availability, provide an ideal environment for studying extreme halophiles and their biogeochemical processes. The present study examined prokaryotic microbial communities and their ecological functions in lentic sediments (with the salinity gradient and time series) using 16S rRNA amplicon sequencing and a metagenomic approach. Our findings revealed a negative correlation between microbial diversity and salinity.

Metabonomic analysis to identify exometabolome changes underlying antifungal and growth promotion mechanisms of endophytic Actinobacterium for sustainable agriculture practice.

In recent years, there has been an increasing focus on microbial ecology and its possible impact on agricultural production, owing to its eco-friendly nature and sustainable use. The current study employs metabolomics technologies and bioinformatics approaches to identify changes in the exometabolome of B24. This research aims to shed light on the mechanisms and metabolites responsible for the antifungal and growth promotion strategies, with potential applications in sustainable agriculture.

Reversed oxidative TCA (roTCA) for carbon fixation by an Acidimicrobiia strain from a saline lake.

Acidimicrobiia are widely distributed in nature and suggested to be autotrophic via the Calvin-Benson-Bassham (CBB) cycle. However, direct evidence of chemolithoautotrophy in Acidimicrobiia is lacking. Here, we report a chemolithoautotrophic enrichment from a saline lake, and the subsequent isolation and characterization of a chemolithoautotroph, Salinilacustristhrix flava EGI L10123T, which belongs to a new Acidimicrobiia family.

Advancements in prokaryotic systematics and the role of Bergey's International Society for Microbial Systematicsin addressing challenges in the meta-data era.

Prokaryotes are ubiquitous in the biosphere, important for human health and drive diverse biological and environmental processes. Systematics of prokaryotes, whose origins can be traced to the discovery of microorganisms in the 17th century, has transitioned from a phenotype-based classification to a more comprehensive polyphasic taxonomy and eventually to the current genome-based taxonomic approach. This transition aligns with a foundational shift from studies focused on phenotypic traits that have limited comparative value to those using genome sequences.

Exploring the Origins and Evolution of Oxygenic and Anoxygenic Photosynthesis in Deeply Branched Cyanobacteriota.

Cyanobacteriota, the sole prokaryotes capable of oxygenic photosynthesis (OxyP), occupy a unique and pivotal role in Earth's history. While the notion that OxyP may have originated from Cyanobacteriota is widely accepted, its early evolution remains elusive. Here, by using both metagenomics and metatranscriptomics, we explore 36 metagenome-assembled genomes from hot spring ecosystems, belonging to two deep-branching cyanobacterial orders: Thermostichales and Gloeomargaritales.

Cultivation of novel Atribacterota from oil well provides new insight into their diversity, ecology, and evolution in anoxic, carbon-rich environments.

Background: The Atribacterota are widely distributed in the subsurface biosphere. Recently, the first Atribacterota isolate was described and the number of Atribacterota genome sequences retrieved from environmental samples has increased significantly; however, their diversity, physiology, ecology, and evolution remain poorly understood.

Results: We report the isolation of the second member of Atribacterota, Thermatribacter velox gen.

Multi-omics insights into the function and evolution of sodium benzoate biodegradation pathway in Benzoatithermus flavus gen. nov., sp. nov. from hot spring.

Biodegradation stands as an eco-friendly and effective approach for organic contaminant remediation. However, research on microorganisms degrading sodium benzoate contaminants in extreme environments remains limited. In this study, we report to display the isolation of a novel hot spring enriched cultures with sodium benzoate (400 mg/L) as the sole carbon source.

Cultivation strategies for prokaryotes from extreme environments.

The great majority of microorganisms are as-yet-uncultivated, mostly found in extreme environments. High-throughput sequencing provides data-rich genomes from single-cell and metagenomic techniques, which has enabled researchers to obtain a glimpse of the unexpected genetic diversity of "microbial dark matter." However, cultivating microorganisms from extreme environments remains essential for dissecting and utilizing the functions of extremophiles.

Methylobacterium nigriterrae sp. nov., isolated from black soil.

An aerobic, Gram-stain-negative, motile rod bacterium, designated as SYSU BS000021, was isolated from a black soil sample in Harbin, Heilongjiang province, China. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the isolate belongs to the genus Methylobacterium, and showed the highest sequence similarity to Methylobacterium segetis KCTC 62267 (98.51%) and Methylobacterium oxalidis DSM 24028 (97.

Ferviditalea candida gen. nov., sp. nov., a novel member of the family Paenibacillaceae isolated from a geothermal area.

Objective: The family Paenibacillaceae is linked to the order Caryophanales. Paenibacillaceae members residing in compost or soil play crucial roles in nutrient recycling and breaking down complex organic materials. However, our understanding of Paenibacillaceae remains limited.

sp. nov., a bacterium isolated from hot spring microbial mat.

A Gram-stain-negative, non-endospore-forming, motile, short rod-shaped strain, designated SYSU G07232, was isolated from a hot spring microbial mat, sampled from Rehai National Park, Tengchong, Yunnan Province, south-western China. Strain SYSU G07232 grew at 25-50 °C (optimum, 37 °C), at pH 5.5-9.

Resource partitioning and amino acid assimilation in a terrestrial geothermal spring.

High-temperature geothermal springs host simplified microbial communities; however, the activities of individual microorganisms and their roles in the carbon cycle in nature are not well understood. Here, quantitative stable isotope probing (qSIP) was used to track the assimilation of C-acetate and C-aspartate into DNA in 74 °C sediments in Gongxiaoshe Hot Spring, Tengchong, China. This revealed a community-wide preference for aspartate and a tight coupling between aspartate incorporation into DNA and the proliferation of aspartate utilizers during labeling.