Lack of functional polyester-biodegrading potential in marine versus terrestrial environments evidenced by an innovative airbrushing technique.

Biodegradable plastics, primarily aliphatic polyesters, degrade to varying extents in different environments. However, the absence of easily implementable techniques for screening microbial biodegradation potential -coupled with the limitations of non-functional omics analyses- has restricted comparative studies across diverse polymer types and ecosystems. In this study, we optimized a novel airbrushing method that facilitates functional analyses by simplifying the preparation of polyester-coated plates for biodegradation screening.

Convergence effect during spatiotemporal succession of lacustrine plastisphere: loss of priority effects and turnover of microbial species.

Succession is a fundamental aspect of ecological theory, but studies on temporal succession trajectories and ecological driving mechanisms of plastisphere microbial communities across diverse colonization environments remain scarce and poorly understood. To fill this knowledge gap, we assessed the primary colonizers, succession trajectories, assembly, and turnover mechanisms of plastisphere prokaryotes and eukaryotes from four freshwater lakes. Our results show that differences in microbial composition similarity, temporal turnover rate, and assembly processes in the plastisphere do not exclusively occur at the kingdom level (prokaryotes and eukaryotes), but also depend on environmental conditions and colonization time.

Assessing microbial plastic degradation requires robust methods.

Plastics are versatile materials that have the potential to propel humanity towards circularity and ultimate societal sustainability. However, the escalating concern surrounding plastic pollution has garnered significant attention, leading to widespread negative perceptions of these materials. Here, we question the role microbes may play in plastic pollution bioremediation by (i) defining polymer biodegradability (i.

Microbial hitchhikers harbouring antimicrobial-resistance genes in the riverine plastisphere.

Background: The widespread nature of plastic pollution has given rise to wide scientific and social concern regarding the capacity of these materials to serve as vectors for pathogenic bacteria and reservoirs for Antimicrobial Resistance Genes (ARG). In- and ex-situ incubations were used to characterise the riverine plastisphere taxonomically and functionally in order to determine whether antibiotics within the water influenced the ARG profiles in these microbiomes and how these compared to those on natural surfaces such as wood and their planktonic counterparts.

Results: We show that plastics support a taxonomically distinct microbiome containing potential pathogens and ARGs.

Assessing the impact of chronic and acute plastic pollution from construction activities and other anthropogenic sources: A case study from the coast of Antofagasta, Chile.

Plastic pollution is a critical environmental issue with far-reaching and not yet fully explored consequences. This study uncovered a significant source of plastic contamination arising from improper application and management of expanded polystyrene (EPS) utilised as expansion joints at a construction site near the coast of Antofagasta, Chile. Through meticulous field observations and calculations, we estimate that a staggering 82.

A mechanistic understanding of polyethylene biodegradation by the marine bacterium Alcanivorax.

Polyethylene (PE) is one of the most recalcitrant carbon-based synthetic materials produced and, currently, the most ubiquitous plastic pollutant found in nature. Over time, combined abiotic and biotic processes are thought to eventually breakdown PE. Despite limited evidence of biological PE degradation and speculation that hydrocarbon-degrading bacteria found within the plastisphere is an indication of biodegradation, there is no clear mechanistic understanding of the process.

Microbial pioneers of plastic colonisation in coastal seawaters.

Plastics, when entering the environment, are immediately colonised by microorganisms. This modifies their physico-chemical properties as well as their transport and fate in natural ecosystems, but whom pioneers this colonisation in marine ecosystems? Previous studies have focused on microbial communities that develop on plastics after relatively long incubation periods (i.e.

Environmental fate of microplastics in the world's third-largest river: Basin-wide investigation and microplastic community analysis.

Rivers have been recognized as major transport pathways for microplastics into the sea but large-scale quantitative data on the environmental fate of riverine microplastics remains limited, hindering proper risk assessment and development of regulatory measures. Microplastics in the whole Yangtze River Basin of China were systematically investigated by sampling the water, sediment, and soil. Microplastics were detected in all samples, with an average abundance of 1.

Cell size matters: Nano- and micro-plastics preferentially drive declines of large marine phytoplankton due to co-aggregation.

Marine plastic pollution represents a key environmental concern. Whilst ecotoxicological data for plastic is increasingly available, its impact upon marine phytoplankton remains unclear. Owing to their predicted abundance in the marine environment and likely interactions with phytoplankton, here we focus on the smaller fraction of plastic particles (~50 nm and ~2 µm polystyrene spheres).

A multi-OMIC characterisation of biodegradation and microbial community succession within the PET plastisphere.

Background: Plastics now pollute marine environments across the globe. On entering these environments, plastics are rapidly colonised by a diverse community of microorganisms termed the plastisphere. Members of the plastisphere have a myriad of diverse functions typically found in any biofilm but, additionally, a number of marine plastisphere studies have claimed the presence of plastic-biodegrading organisms, although with little mechanistic verification.

Environmentally relevant concentrations of titanium dioxide nanoparticles pose negligible risk to marine microbes.

Nano-sized titanium dioxide (nTiO) represents the highest produced nanomaterial by mass worldwide and, due to its prevalent industrial and commercial use, it inevitably reaches the natural environment. Previous work has revealed a negative impact of nTiO upon marine phytoplankton growth, however, studies are typically carried out at concentrations far exceeding those measured and predicted to occur in the environment currently. Here, a series of experiments were carried out to assess the effects of both research-grade nTiO and nTiO extracted from consumer products upon the marine dominant cyanobacterium, , and natural marine communities at environmentally relevant and supra-environmental concentrations (, 1 μg L to 100 mg L).

Pili allow dominant marine cyanobacteria to avoid sinking and evade predation.

How oligotrophic marine cyanobacteria position themselves in the water column is currently unknown. The current paradigm is that these organisms avoid sinking due to their reduced size and passive drift within currents. Here, we show that one in four picocyanobacteria encode a type IV pilus which allows these organisms to increase drag and remain suspended at optimal positions in the water column, as well as evade predation by grazers.

A Novel Ca Signaling Pathway Coordinates Environmental Phosphorus Sensing and Nitrogen Metabolism in Marine Diatoms.

Diatoms are a diverse and globally important phytoplankton group, responsible for an estimated 20% of carbon fixation on Earth. They frequently form spatially extensive phytoplankton blooms, responding rapidly to increased availability of nutrients, including phosphorus (P) and nitrogen (N). Although it is well established that diatoms are common first responders to nutrient influxes in aquatic ecosystems, little is known of the sensory mechanisms that they employ for nutrient perception.

Phytoplankton trigger the production of cryptic metabolites in the marine actinobacterium Salinispora tropica.

Filamentous members of the phylum Actinobacteria are a remarkable source of natural products with pharmaceutical potential. The discovery of novel molecules from these organisms is, however, hindered because most of the biosynthetic gene clusters (BGCs) encoding these secondary metabolites are cryptic or silent and are referred to as orphan BGCs. While co-culture has proven to be a promising approach to unlock the biosynthetic potential of many microorganisms by activating the expression of these orphan BGCs, it still remains an underexplored technique.

Marine Plastic Debris: A New Surface for Microbial Colonization.

Plastics become rapidly colonized by microbes when released into marine environments. This microbial community-the Plastisphere-has recently sparked a multitude of scientific inquiries and generated a breadth of knowledge, which we bring together in this review. Besides providing a better understanding of community composition and biofilm development in marine ecosystems, we critically discuss current research on plastic biodegradation and the identification of potentially pathogenic "hitchhikers" in the Plastisphere.

Mechanisms of silver nanoparticle toxicity on the marine cyanobacterium Prochlorococcus under environmentally-relevant conditions.

Global demand for silver nanoparticles (AgNPs), and their inevitable release into the environment, is rapidly increasing. AgNPs display antimicrobial properties and have previously been recorded to exert adverse effects upon marine phytoplankton. However, ecotoxicological research is often compromised by the use of non-ecologically relevant conditions, and the mechanisms of AgNP toxicity under environmental conditions remains unclear.

Beyond oil degradation: enzymatic potential of Alcanivorax to degrade natural and synthetic polyesters.

Pristine marine environments are highly oligotrophic ecosystems populated by well-established specialized microbial communities. Nevertheless, during oil spills, low-abundant hydrocarbonoclastic bacteria bloom and rapidly prevail over the marine microbiota. The genus Alcanivorax is one of the most abundant and well-studied organisms for oil degradation.

Plasticizer Degradation by Marine Bacterial Isolates: A Proteogenomic and Metabolomic Characterization.

Many commercial plasticizers are toxic endocrine-disrupting chemicals that are added to plastics during manufacturing and may leach out once they reach the environment. Traditional phthalic acid ester plasticizers (PAEs), such as dibutyl phthalate (DBP) and bis(2-ethyl hexyl) phthalate (DEHP), are now increasingly being replaced with more environmentally friendly alternatives, such as acetyl tributyl citrate (ATBC). While the metabolic pathways for PAE degradation have been established in the terrestrial environment, to our knowledge, the mechanisms for ATBC biodegradation have not been identified previously and plasticizer degradation in the marine environment remains underexplored.

Early Colonization of Weathered Polyethylene by Distinct Bacteria in Marine Coastal Seawater.

Plastic debris in aquatic environments is rapidly colonized by a diverse community of microorganisms, often referred to as the "Plastisphere." Given that common plastics are derived from fossil fuels, one would expect that Plastispheres should be enriched with obligate hydrocarbon-degrading bacteria (OHCB). So far, though, different polymer types do not seem to exert a strong effect on determining the composition of the Plastisphere, and putative biodegrading bacteria are only found as rare taxa within these biofilms.

Understanding microbial community dynamics to improve optimal microbiome selection.

Background: Artificial selection of microbial communities that perform better at a desired process has seduced scientists for over a decade, but the method has not been systematically optimised nor the mechanisms behind its success, or failure, determined. Microbial communities are highly dynamic and, hence, go through distinct and rapid stages of community succession, but the consequent effect this may have on artificially selected communities is unknown.

Results: Using chitin as a case study, we successfully selected for microbial communities with enhanced chitinase activities but found that continuous optimisation of incubation times between selective transfers was of utmost importance.

Riding the wave of genomics to investigate aquatic coliphage diversity and activity.

Bacteriophages infecting Escherichia coli (coliphages) have been used as a proxy for faecal matter and water quality from a variety of environments. However, the diversity of coliphages that is present in seawater remains largely unknown, with previous studies largely focusing on morphological diversity. Here, we isolated and characterized coliphages from three coastal locations in the United Kingdom and Poland.