The number of social contacts of mammals is positively correlated with the diversity of their gut microbes. There is some evidence that sociality also affects microbes in the respiratory tract. We tested whether the airway microbiota of cetacean species differ depending on the whales' level of sociality. We sampled the blow of blue (Balaenoptera musculus), grey (Eschrichtius robustus), humpback (Megaptera

The importance of short‐chained aliphatic polyamines (PAs) to bacterioplankton‐mediated carbon and nitrogen cycles has been repeatedly proposed. However, bacterial taxa and genes involved in the transformations of different PA compounds and their potential spatial variations remain unclear. This study collected surface bacterioplankton from nearshore, offshore, and open ocean stations in the Gulf of

Arbuscular mycorrhizal fungi (AMF) play central roles in terrestrial ecosystems by interacting with both above and belowground communities as well as by influencing edaphic properties. The AMF communities associated with the roots of the fern Botrychium lunaria (Ophioglossaceae) were sampled in four transects at 2400 m a.s.l. in the Swiss Alps and analyzed using metabarcoding. Members of four Glomeromycota

Studies on bacterial physiology are incomplete without knowledge of the signaling and regulatory systems that a bacterium uses to sense and respond to its environment. Two‐component systems are among the most prevalent bacterial signaling systems, and they control essential and secondary physiological processes; however, even in model organisms, we lack a complete understanding of the signals sensed

Anoxic marine zones (AMZs), also known as ‘oxygen‐deficient zones’, contribute to the loss of fixed nitrogen from the ocean by anaerobic microbial processes. While these microbial processes associated with the nitrogen cycle have been extensively studied, those linked to the carbon cycle in AMZs have received much less attention, particularly the autotrophic carbon fixation —a crucial component of

Massive amplicon sequencing approaches to characterize the diversity of microbial eukaryotes in sediments are scarce and controls about the effects introduced by different methods to recover DNA are lacking. In this study, we compare the performance of the melting seawater‐ice elution method on the characterization of benthic protist communities by 18S rRNA gene metabarcoding with results obtained

Collimonas fungivorans Ter331 (CfTer331) is a soil bacterium that produces collimomycin, a secondary metabolite that inhibits the vegetative growth of fungi. Here we show that CfTer331 can also interfere with fungal spore germination and that collimomycin biosynthesis is required for this activity. More specifically, in co‐cultures of Aspergillus niger N402 (AnN402) co‐nidiospores with CfTer331, the

Bioaerosols are an important component of the total atmospheric aerosol load, with implications for human health, climate feedbacks and the distribution and dispersal of microbial taxa. Bioaerosols are sourced from marine, freshwater and terrestrial surfaces, with different mechanisms potentially responsible for releasing biological particles from these substrates. Little is known about the production

Transmission electron microscopy (TEM) and rock magnetic study of ferromanganese nodule sample JC120-104B collected from Clarion- Clipperton Zone (CCZ) in the eastern Pacific Ocean indicate the presence of biogenic magnetite (magnetofossils). First Order Reversal Curves (FORCs) and decomposition of Isothermal Remanent Magnetization (IRM) curves were used as the main tool for the characterization of

Methylmercury is a neurotoxin that bioaccumulates from seawater to high concentrations in marine fish, putting human and ecosystem health at risk. High methylmercury levels have been found in the oxic subsurface waters of all oceans, but only anaerobic microorganisms have been shown to efficiently produce methylmercury in anoxic environments. The microaerophilic nitrite-oxidizing bacteria Nitrospina

Copper is an essential element but in excess is highly toxic and therefore cytoplasmic levels must be tightly controlled. Member of the genus Burkholderia are highly resistant to various heavy metals and are often isolated from acidic soils where copper bioavailability is high. In this study, we employed transposon sequencing (Tn-Seq) to identify copper resistance genes in Burkholderia cenocepacia

Meromictic lakes are stratified lakes that typically stimulate phototrophic anoxic microbial metabolism, including the transformation of sulphur. Less studied are the transformations of mercury in these environments, and the microorganisms, which mediate these reactions. In order to further an understanding of redox species, mercury and microbial populations in meromictic lakes, we examined the geochemistry

Arbuscular mycorrhizal fungi (AMF) play an important role in maintaining plant diversity and productivity in grassland ecosystems. However, very few studies have investigated how AMF and plant communities co-vary between contrasting environments in natural ecosystems. Intensive sampling (50 soil samples) was conducted in natural open grasslands at both 3570 and 4556 m on Mount Segrila on the Southeast

Land-use change has been identified as the most severe threat to biodiversity. Soils are important biodiversity reservoirs, but to what extent conversion of high-altitude temperate forest to arable land affects taxonomic and functional soil biodiversity is still largely unknown. Shotgun metagenomics was used to determine the taxonomic and functional diversity of bacteria, archaea and DNA virus in terms

The relative importance of host control, environmental effects and stochasticity in the assemblage of host-associated microbiomes is being debated. We analysed the microbiome among fly populations that were sampled across Europe by the European Drosophila Population Genomics Consortium (DrosEU). In order to better understand the structuring principles of the natural D. melanogaster microbiome, we combined

The spatiotemporal dynamics for marine viral populations has only recently been explored. However, nothing is known about temporal activities of the uncultured Pelagibacter virus vSAG 37-F6, which was discovered by single-virus genomics as potentially the most abundant marine virus. Here, we investigate the diel cycling of 37-F6 virus and the putative SAR11 host using coastal and oceanic transcriptomic

The world's oceans are becoming increasingly polluted by plastic waste. In the marine environment, larger plastic pieces may degrade into nanoscale (<100 nm in at least one dimension) plastic particles due to natural weathering effects. We observe that the presence of 20 nm plastic nanoparticles at concentrations below 200 ppm had no impact on planktonic growth of a panel of heterotrophic marine bacteria

Degradation of amino acids is an important process in methanogenic environments. Early studies in the 1980s focused on isolated clostridia species to study the degradation behaviours. However, it is now well-recognized that isolated species may not represent those with important roles in situ. This study conducted a continuous enrichment experiment with focus on the comparison of the microbial communities

Arsenic is a toxin, ranking first on the Agency for Toxic Substances and Disease Registry and the Environmental Protection Agency Priority List of Hazardous Substances. Chronic exposure increases the risk of a broad range of human illnesses, most notably cancer; however, there is significant variability in arsenic-induced disease among exposed individuals. Human genetics is a known component, but it

It has been recently shown that magnetite nanoparticles (nanoFe3 O4 ) can facilitate methanogenic syntrophy but the effect of magnetite on methanogenesis alone remains elusive. Here we show that aceticlastic methanogenesis by Methanosarcina mazei is accelerated by magnetite and is correlated with the redox cycling of structural Fe(II) and Fe(III) in the mineral. An enrichment and its closest pure culture

Rhizomicrobiome, the communities of microorganisms surrounding the root of the plant, plays a vital role in promoting plant growth and health. The composition of rhizomicrobiome is dynamic both temporally and spatially, and is influenced greatly by the plant host and environmental factors. One of the key influencing factors is rhizodeposits, composed of root-released tissue cells, exudates, lysates

Euglenophyceae are unicellular algae with the majority of their diversity known from small freshwater reservoirs. Only two dozen species have been described to occur in marine habitats, but their abundance and diversity remain unexplored. Phylogenetic studies revealed marine prasinophyte green alga, Pyramimonas parkeae, as the closest extant relative of the euglenophytes' plastid, but similarly to

Flagella are the well-known structural appendages used by bacteria for motility. Although generally reported to be non-motile, the enteropathogenic bacterial species Escherichia albertii produces flagella intermittently. We found that E. albertii expressed flagella under specific environmental conditions. After several generations (involving 4 to 12-h incubations), six of the twelve strains we investigated

To understand factors that influence the assembly of microbial communities, we inoculated Medicago sativa with a series of nested bacterial synthetic communities and grew plants in distinct nitrogen concentrations. Two isolates in our eight-member synthetic community, Williamsia sp. R60 and Pantoea sp. R4, consistently dominate community structure across nitrogen regimes. While Pantoea sp. R4 consistently

Environmental cues that regulate motility are poorly understood, but specific carbon and nitrogen sources, such as casamino acids (CAA), are known to stimulate motility in model organisms. However, natural environments are commonly more nutrient-limited than laboratory growth media, and the effect of energy-rich CAA on the motility of oligotrophic microorganisms is unknown. In this study, an extreme

In recent years, there has been an increase in studies on the implications of gut microbiota (GM) on the behaviour of children with autism spectrum disorders (ASD) due to a dysbiosis in GM that can trigger onset, development or progression of ASD through the microbiota-gut-brain axis. The aim of this study is to carry out a systematic review of articles from the last 6 years that analyse GM in children

Acetogenic bacteria are a group of strictly anaerobic bacteria that may have been first life forms on Earth since they employ an ancient pathway for CO2 fixation into acetyl-CoA that is coupled to the synthesis of ATP, the Wood-Ljungdahl pathway. Electrons for CO2 reduction are derived from oxidation of H2 or CO and thus, these bacteria can grow lithotrophically on gases present on early Earth. Among

Cyclic diguanylate (c-di-GMP) is a broadly conserved bacterial signalling molecule that modulates diverse cellular processes, such as biofilm formation, colony morphology and swimming motility. The intracellular level of c-di-GMP is controlled by diguanylate cyclases (DGCs) with GGDEF domain and phosphodiesterases (PDEs) with either EAL or HD-GYP domain. Pseudomonas putida KT2440 has a large group

Plant- and alga-associated bacterial communities are generally described via 16S rDNA metabarcoding using universal primers. As plastid genomes encode 16S rDNA related to cyanobacteria, these data sets frequently contain >90% plastidial sequences, and the bacterial diversity may be under-sampled. To overcome this limitation we evaluated in silico the taxonomic coverage for four primer combinations

Electroactive type IV pili, or e-pili, are used by some microbial species for extracellular electron transfer. Recent studies suggest that e-pili may be more phylogenetically and structurally diverse than previously assumed. Here, we used updated aromatic density thresholds (≥9.8% aromatic amino acids, ≤22-aa aromatic gaps and aromatic amino acids at residues 1, 24, 27, 50 and/or 51, and 32 and/or

Multispecies biofilms are structured and spatially defined communities, where interspecies interactions impact assembly and functionality. Here, we compared the spatial organization and growth of bacterial cells in differently composed biofilm communities over time to determine links between interspecies interactions and selection for biofilm phenotypes of individual species. An established model community

We characterized ammonia-oxidizing archaea (AOA) and bacteria (AOB) from salt marsh sediments in the Gulf of Mexico over 5 years to identify environmental drivers of nitrifying community patterns following the Deepwater Horizon oil spill. Samples were collected from oiled and unoiled sites in July of 2012-2016 from 12 marshes spanning three regions on the Louisiana coast. No consistent oil effect was

Amino acids are vital components in cell metabolism. Leucine is a regulatory factor that generates significant impact on protein synthesis/turnover, modulates diverse cellular signalling pathways and participates in oxidative processes and immune responses. Here, we identified and characterized the functions of a leucine-associated Zn2 Cys6 -type transcription factor, MoLeu3. Disruption of MoLEU3 resulted

In recent years, whole shotgun metagenomics (WSM) of complex microbial communities has become an established technology to perform compositional analyses of complex microbial communities, an approach that is heavily reliant on bioinformatic pipelines to process and interpret the generated raw sequencing data. However, the use of such in silico pipelines for the microbial taxonomic classification of

In silico and empirical quantification of viruses is paramount for obtaining information on viral populations that have a major impact on biogeochemical cycles. The uncultured Pelagibacter virus vSAG 37-F6 discovered via single-virus genomics is one of the most abundant and cosmopolitan marine viruses; however, little is understood about its temporal variation. Here, we estimated the absolute number

During bloom events, Escherichia coli cell counts increase to between 10,000 and 100,000 cfu/100 ml of water. The strains responsible for bloom events belong to E. coli phylogenetic groups A and B1, and all have acquired a capsule from Klebsiella. A pan-genome comparison of phylogroup A E. coli revealed that the ferric citrate uptake system (fecIRABCDE) was overrepresented in phylogroup A bloom strains