Search Results (173)

Protein degradation plays a fundamental role in maintaining protein homeostasis and ensures proper cellular function by regulating protein quality and quantity. Heat shock protein 100 (Hsp100), found in bacteria, plants, and fungi, is a unique chaperone family responsible for rescuing misfolded proteins from aggregated states in an ATP-dependent manner. To date, they are primarily known to mediate heat stress adaptation and enhance cellular survival under extreme conditions in higher plants and algae. Resting cyst formation in dinoflagellates is widely recognized as a response to adverse conditions, which offers an adaptive advantage to endure harsh environmental extremes that are unsuitable for vegetative cell growth and survival. In this study, based on a full-length cDNA sequence, we characterized an Hsp100 gene (SaHsp100) from the cosmopolitan bloom-forming dinoflagellate Scrippsiella acuminata, aiming to examine its life stage-specific expression patterns and preliminarily explore its potential functions. The qPCR results revealed that Hsp100 transcript levels were significantly elevated in newly formed resting cysts compared to vegetative cells and continued to increase during storage under simulated marine sediment conditions (darkness, low temperature, and anoxia). Parallel reaction monitoring (PRM)-based quantification further confirmed that Hsp100 protein levels were significantly higher in resting cysts than in vegetative cells and increased after three months of storage. These findings collectively highlighted the fundamental role of Hsp100 in the alteration of the life cycle and dormancy maintenance of S. acuminata, likely by enhancing stress adaptation and promoting cell survival through participation in proteostasis maintenance, particularly under natural sediment-like conditions that trigger severe abiotic stress. Our work deepens the current understanding of Hsp family members in dinoflagellates, paving the way for future investigations into their ecological relevance within this ecologically significant group. Full article

Necrotizing soft tissue infections (NSTIs) are serious and aggressive infections which can result in significant morbidity and mortality. Both prompt surgical intervention and early antibiotics can decrease patient mortality. Based on microbiology, NSTIs can be categorized into four different types. Type I is polymicrobial, caused by a mix of both anaerobic and aerobic bacteria. Type II is monomicrobial, usually caused by either Streptococcus or Staphylococcus. Type III infections are caused by Gram-negative bacteria, often marine-related organisms, such as Vibrio. Lastly, Type IV infections are caused by fungi, and they are often associated with trauma. Despite the possibility of all these different pathogens in NSTI, early therapy often consists of a broad Gram-positive antimicrobial such as linezolid or vancomycin, and a broad Gram-negative agent such as piperacillin/tazobactam. Multiple factors including patient comorbidities, environmental exposures, and clinical presentation must also be considered when choosing antimicrobial agents and dosing. Adjunct medical therapies such as intravenous immunoglobulin (IVIG) and the antibiotics clindamycin and linezolid that are aimed at toxin suppression may be utilized to improve outcomes. Microbiological data are critical for optimizing the antimicrobial regimen. Full article

In the mid-twentieth century, the solid waste generated was mostly made of biodegradable materials. However, the invention of plastic and its widespread use have led to a staggering accumulation of plastic in the environment, posing a severe threat to the biosphere. The environmental degradation of plastic can take thousands of years and poses a significant concern for environmental and human health. Until recently, it was thought that some plastics were non-biodegradable; however, there are microorganisms capable of degrading both plastics derived from fossil resources and those from biomass or renewable resources. This review aims to highlight the impact of plastic waste on the environment and the biosphere, as well as the great taxonomic diversity of microorganisms potentially linked to plastic degradation. Research in plastic biodegradability includes the identification of bacteria, fungi, archaea, and algae from virtually any environment: soil, atmosphere, landfills, freshwater, seawater, marine sediments, rumen, and waxworm guts. Identifying microbial consortia that degrade plastic and improving their degrading activity could shorten the plastic degradation time and reduce its uncontrolled accumulation around the globe. Research in this field is vital for advancing biodegradable plastics and elucidating the potential and limitations of microbial degradation as a large-scale approach to plastic pollution. Full article

The increasing demand for sustainable, economical, and environmentally friendly solutions has positioned microalgae as promising candidates in biotechnology, particularly in food, feed, nutraceutical, pharmaceutical, biofuel, and bioremediation applications. This review explores the role of the Nannochloropsis genus and other marine oleaginous microalgae in co-cultivation systems, highlighting their mechanisms of interaction with various microorganisms and their potential for various biotechnological purposes. Case studies of Nannochloropsis sp. co-cultures with other microalgae, bacteria, and fungi are presented. The different types of associations are described as alternative strategies to enhance biomass productivity, lipid accumulation, and nutrient recycling. A key focus of this review is the potential of Nannochloropsis microalgae co-cultivation in food, as it is part of the list of microalgae to be approved for consumption in the European Union, discussing their rich nutritional value, safety, and regulatory status. Additionally, the role of microalgae in the alternative protein sector is explored, with particular emphasis on their integration in cultivated meat products as nutrient suppliers and metabolic partners for animal cells. Despite their potential, several challenges, such as scale-up, contamination risk, and strain selection, remain key obstacles to the widespread adoption of microalgal biotechnology. Future research should focus on optimizing microalgae-based co-cultures for food applications, addressing safety concerns, and further investigating their integration into functional foods and cellular agriculture products. Full article

The crucial role of plant–microbe interactions in seagrass growth and overall fitness is widely recognized and known to influence plant response to stress. Human-induced changes in coastal ecosystems necessitate efficient descriptors for seagrass monitoring. Recently, for Posidonia oceanica meadows, an integrative approach combining ecophysiological descriptors with bacterial communities has been successfully applied. Conversely, the mycobiota remains largely unexplored and fungal communities cannot be included yet as a putative descriptor. This study aims to evaluate the ecological status of two P. oceanica meadows in the Akrotiri Bay (Cyprus), located under different geomorphological features (depth and seabed type) and degrees of human pressure (port proximity vs. Marine Protected Area). A set of descriptors including morphometry, biochemical markers and bacterial communities collected in 2023 are compared with those collected, at the same sites, in 2017. Furthermore, the investigation of the leaf-associated microbial community included the underrepresented fungal communities, in addition to the bacterial ones, to evaluate their usefulness in evaluating the plant conservation status. Results indicated a good P. oceanica conservation status at both sites, showing an amelioration in the Limassol port meadow from 2017. In 2023, the biometrical/biochemical descriptors were found comparable across sites as the bacterial communities, differing from 2017 results. Noteworthy, fungal communities exhibited significant differences between sites, with a clear reduction, in the Limassol port meadow, of the dominant Posidoniomyces atricolor which is known as a specific colonizer of P. oceanica roots. These results confirm the strong relationship between P. atricolor and P. oceanica host, and suggest its sensitivity to environmental changes, able to keep track of ecological shifts. Full article

Mangroves are coastal ecosystems of great ecological importance, located in transition areas between marine and terrestrial environments, predominantly found in tropical and subtropical regions. In Brazil, these biomes are present along the entire coastline, playing essential environmental roles such as sediment stabilization, coastal erosion control, and the filtration of nutrients and pollutants. The unique structure of the roots of some mangrove tree species facilitates sediment deposition and organic matter retention, creating favorable conditions for the development of rich and specialized biodiversity, including fungi, bacteria, and other life forms. Furthermore, mangroves serve as important nurseries for many species of fish, crustaceans, and birds, being fundamental to maintaining trophic networks and the local economy, which relies on fishing resources. However, these ecosystems have been significantly impacted by anthropogenic pressures and global climate change. In recent years, the increase in average global temperatures, rising sea levels, changes in precipitation patterns, and ocean acidification have contributed to the degradation of mangroves. Additionally, human activities such as domestic sewage discharge, pollution from organic and inorganic compounds, and alterations in hydrological regimes have accelerated this degradation process. These factors directly affect the biodiversity present in mangrove sediments, including the fungal community, which plays a crucial role in the decomposition of organic matter and nutrient cycling. Fungi, which include various taxonomic groups such as Ascomycota, Basidiomycota, and Zygomycota, are sensitive to changes in environmental conditions, making the study of their diversity and distribution relevant for understanding the impacts of climate change and pollution. In particular, fungal bioremediation has gained significant attention as an effective strategy for mitigating pollution in these sensitive ecosystems. Fungi possess unique abilities to degrade or detoxify environmental pollutants, including heavy metals and organic contaminants, through processes such as biosorption, bioaccumulation, and enzymatic degradation. This bioremediation potential can help restore the ecological balance of mangrove ecosystems and protect their biodiversity from the adverse effects of pollution. Recent studies suggest that changes in temperature, salinity, and the chemical composition of sediments can drastically modify microbial and fungal communities in these environments, influencing the resilience of the ecosystem. The objective of this narrative synthesis is to point out the diversity of fungi present in mangrove sediments, emphasizing how the impacts of climate change and anthropogenic pollution influence the composition and functionality of these communities. By exploring these interactions, including the role of fungal bioremediation in ecosystem restoration, it is expected that this study would provide a solid scientific basis for the conservation of mangroves and the development of strategies to mitigate the environmental impacts on these valuable ecosystems. Full article

As a mycotoxin, aflatoxin B₁ (AFB₁) has attracted increasing attention due to its highly toxic effects, such as teratogen, carcinogen, and mutagen. AFB₁-producing fungi have been found in both terrestrial and marine sources. Over the last two years, the marine-derived bacteria Kocuria rosea has shown the ability to degrade AFB₁. However, no studies have yet explored the aflatoxin degradation potential in the genus Kocuria, and the molecular basis of aflatoxin metabolisms by strain has not yet been investigated. In this study, we first compared and analyzed the genomic features of 13 bacteria of the genus Kocuria by comparative genomic analysis and investigated the evolutionary patterns (evolutionary selection pressure analysis and gene family expansion analysis) and pan and core genomes of Kocuria strains. It was found that Kocuria genus strains showed high potential in the bioremediation of aromatic compounds and aflatoxin degradation. In addition, this study revealed 1421 differentially expressed genes and 752 upregulated genes between the aflatoxin group and the control group through transcriptome analysis and conducted functional annotation and analysis of functional enrichment. According to the expression and functional analysis of upregulated genes, the enzymes and genes (cytochrome P450, oxidoreductase, intradiol ring-cleavage dioxygenase, hydrolase, and monooxygenase) involved in the aflatoxin degradation of Kocuria rosea were screened. These findings indicate the potential of Kocuria rosea in the remediation of aflatoxin contamination and provide a foundation and direction for the further excavation of novel degradation genes, exploration of degradation mechanisms, and genomic modification. Full article

Marine microorganisms have emerged as prolific sources of bioactive natural products, offering a large chemical diversity and a broad spectrum of biological activities. Over the past decade, significant progress has been made in discovering and characterizing these compounds, pushed by technological innovations in genomics, metabolomics, and bioinformatics. Furthermore, innovative isolation and cultivation approaches have improved the isolation of rare and difficult-to-culture marine microbes, leading to the identification of novel secondary metabolites. Advances in synthetic biology and metabolic engineering have further optimized natural product yields and the generation of novel compounds with improved bioactive properties. This review highlights key developments in the exploitation of marine bacteria, fungi, and microalgae for the discovery of novel natural products with potential applications in diverse fields, underscoring the immense potential of marine microorganisms in the growing Blue Economy sector. Full article

L-asparaginase (ASNase) hydrolyzes L-asparagine to L-aspartic acid and ammonia and has been used as an antitumor agent for the treatment of acute lymphoblastic leukemia. ASNase has also been used to mitigate the suspected carcinogenic effects of acrylamide in foods. Commercial ASNases currently used in the pharmaceutical and food industries are produced by microorganisms, such as bacteria and fungi. However, their toxicity and poor thermal stability limit their application. Therefore, identifying novel sources of ASNase is critical. In the present study, we identified an asparaginase-producing marine bacterial strain, GH-W2b, as a Pseudomonas species. Based on the plate assay results, GH-W2b produced ASNase with marginal L-glutaminase (GLNase) activity, which has been reported to cause adverse effects in clinical ASNases. The ASNase activity of GH-W2b was maximized at 50–65 °C and pH 7.0–8.5. Notably, the activities were consistent at a wide range of NaCl concentrations (0–15%) at 37 °C. In addition, compared to the control (no pre-incubation), ASNase activities were retained (>87%) by 2 h pre-incubation at 4–37 °C. Overall, our results suggest that GH-W2b ASNase has the potential to serve as a candidate for the development of salt-tolerant and/or alternative ASNases in pharmaceutical and food products. Full article

Fucose, fucose-containing oligosaccharides, and fucose-containing polysaccharides have been widely applied in the fields of food and medicine, including applications in Helicobacter pylori eradication and renal function protection. Fucose-containing carbohydrates (FCCs) derived from marine organisms such as seaweed, invertebrates, microalgae, fungi, and bacteria have garnered growing attention due to their diverse bioactivities and potential therapeutic applications. Marine-derived FCCs characterized by high fucose residue content and extensive sulfate substitution, including fucoidan, fucosylated chondroitin sulfate, and fucose-rich microbial exopolysaccharides, have demonstrated significant potential in promoting gastrointestinal health. This review describes the unique structural features of FCCs and summarizes their health benefits, including regulation of gut microbiota, modulation of microbial metabolism, anti-adhesion activities against H. pylori and gut pathogens, protection against inflammatory injuries, and anti-tumor activities. Additionally, this review discusses the structural characteristics that influence the functional properties and the limitations related to the activity research and preparation processes of FCCs, providing a balanced perspective on the application potential and challenges of FCCs with specific structures for the regulation of gastrointestinal health and diseases. Full article

The anchoring and mooring of boats mechanically damage Posidonia oceanica plants; however, no information is available on the effect of this kind of damage on the plant holobiont, i.e., on the associated bacterial and fungal communities. Indeed, bacterial communities are known to change under different plant stress conditions but the dynamics of seagrass-associated fungi remain largely unexplored. We used DNA metabarcoding to profile the bacterial and fungal colonizers of two nearby P. oceanica patches in the Villefranche-sur-Mer bay (France) differing by the amount of exposure to mechanical stress due to boat transit and anchoring. Bacterial communities showed a significant reduction in diversity with an increase in Vibrio sp. in the rhizome and root samples from the impacted site, where the accumulation of dead organic material favors opportunistic heterotrophs. Conversely, fungal communities showed increased diversity in the leaf samples from the impacted site, where a reduction in the dominant P. oceanica host-specific mutualistic endosymbiont, Posidoniomyces atricolor, was found. This change was probably due to the opening up of new colonizable niches for several fungal species. Although this study represents a preliminary assessment of the effect of mechanical stresses on P. oceanica-associated microbial communities, it further supports their putative use as a seagrass descriptor. Full article

The chitinous skeleton of the marine demosponge Ianthella basta exhibits a unique network-like 3D architecture, excellent capillary properties, and chemical inertness, making it highly suitable for interdisciplinary research, especially in biomedical applications. This study investigates the potential of renewable I. basta chitinous scaffolds for drug delivery and wound dressing. The scaffolds, characterized by a microtubular structure, were impregnated with selected commercially available antiseptics, including solutions with hydrophilic and hydrophobic properties. Evaluations against selected clinical strains of bacteria, as well as fungi, demonstrated significant zones of growth inhibition with antiseptics such as brilliant green, gentian violet, decamethoxine, and polyhexanide. Notably, the antibacterial properties of these antiseptic-treated chitin matrices persisted for over 72 h, effectively inhibiting microbial growth in fresh cultures. These findings highlight the considerable potential of I. basta chitin scaffolds as sustainable, innovative biomaterials for controlled drug release and wound dressing applications. Full article

Antimicrobial resistance is a critical global health issue, with rising resistance among bacteria and fungi. Marine organisms have emerged as promising, but underexplored, sources of new antimicrobial agents. Among them, marine polychaetes, such as Halla parthenopeia, which possess chemical defenses, could attract significant research interest. This study explores the antimicrobial properties of hallachrome, a unique anthraquinone found in the purple mucus of H. parthenopeia, against Gram-negative bacteria (Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 9027), Gram-positive bacteria (Enterococcus faecalis ATCC 29212, Staphylococcus aureus ATCC 6538, Staphylococcus epidermidis ATCC 12228), and the most common human fungal pathogen Candida albicans ATCC 10231. Antibacterial susceptibility testing revealed that Gram-negative bacteria were not inhibited by hallachrome at concentrations ≤2 mM. However, Gram-positive bacteria showed significant growth inhibition at 0.12–0.25 mM, while C. albicans was inhibited at 0.06 mM. Time-kill studies demonstrated dose-dependent growth inhibition of susceptible strains by hallachrome, which exerted its effect by altering the membrane permeability of C. albicans, E. faecalis, and S. epidermidis after 6 h and S. aureus after 24 h. Additionally, hallachrome significantly reduced biofilm formation and mature biofilm in S. aureus, E. faecalis, and C. albicans. Additionally, it inhibited hyphal growth in C. albicans. These findings highlight hallachrome’s potential as a novel antimicrobial agent, deserving further exploration for clinical experimentation. Full article

Antibiotic resistance emerged shortly after the discovery of the first antibiotic and has remained a critical public health issue ever since. Managing antibiotic resistance in clinical settings continues to be challenging, particularly with the rise of superbugs, or bacteria resistant to multiple antibiotics, known as multidrug-resistant (MDR) bacteria. This rapid development of resistance has compelled researchers to continuously seek new antimicrobial agents to curb resistance, despite a shrinking pipeline of new drugs. Recently, the focus of antimicrobial discovery has shifted to plants, fungi, lichens, endophytes, and various marine sources, such as seaweeds, corals, and other microorganisms, due to their promising properties. For this review, an extensive search was conducted across multiple scientific databases, including PubMed, Elsevier, ResearchGate, Scopus, and Google Scholar, encompassing publications from 1929 to 2024. This review provides a concise overview of the mechanisms employed by bacteria to develop antibiotic resistance, followed by an in-depth exploration of plant secondary metabolites as a potential solution to MDR pathogens. In recent years, the interest in plant-based medicines has surged, driven by their advantageous properties. However, additional research is essential to fully understand the mechanisms of action and verify the safety of antimicrobial phytochemicals. Future prospects for enhancing the use of plant secondary metabolites in combating antibiotic-resistant pathogens will also be discussed. Full article

Retinopathy of prematurity (ROP) is a vascular disorder affecting the retinas of preterm infants. This condition arises when preterm infants in incubators are exposed to high oxygen levels, leading to oxidative stress, inflammatory responses, and a downregulation of vascular endothelial growth factors, which causes the loss of retinal microvascular capillaries. Upon returning to room air, the upregulation of vascular growth factors results in abnormal vascular growth of retinal endothelial cells. Without appropriate intervention, ROP can progress to blindness. The prevalence of ROP has risen, making it a significant cause of childhood blindness. Current treatments, such as laser therapy and various pharmacologic approaches, are limited by their potential for severe adverse effects. Therefore, a deeper understanding of ROP’s pathophysiology and the development of innovative treatments are imperative. Natural products from plants, fungi, bacteria, and marine organisms have shown promise in treating various diseases and have gained attention in ROP research due to their minimal side effects and wide-ranging beneficial properties. This review discusses the roles and mechanisms of natural products that hold potential as therapeutic agents in ROP management. Full article