Candida albicans, the most common opportunistic pathogenic fungus, is also the main pathogenic organism for oral candidiasis. This condition is particularly prevalent among the elderly, children, and individuals undergoing radiotherapy or suffering from HIV. The lack of new antifungal drugs, and drug resistance coupled with the side effects of current antifungal agents have increased the challenges of clinical antifungal therapies. Polyenes, including amphotericin B and nystatin, are clinical fungicidal drugs, however, their side effects and low solubility have limited their clinical applications. Here, we identified that moxidectin, a novel approved antiparasitic agent, could synergize with both amphotericin B and nystatin to inhibit the growth and biofilm formation of Candida albicans including 60 clinical isolates. The transcriptome and RT-PCR analysis indicated that moxidectin activated the biosynthesis pathway of ergosterol, the direct target of polyenes, further being verified by the loss of the synergistic activities with polyenes against ergosterol pathway mutants, including Δ/Δerg3, Δ/Δerg11 and Δ/Δerg3 Δ/Δerg11. Moxidectin was then confirmed to elevate the ergosterol biosynthesis levels of C. albicans and enhance the binding between cells and polyenes. In a mouse oral candidiasis model, moxidectin combined with low dosages of polyenes to significantly reduce the infection area, colonization of C. albicans and the inflammatory degree of tongue mucosa. Our study originally demonstrated that moxidectin could activate the ergosterol biosynthesis then elevate the ergosterol contents to enhance the antifungal effects of polyenes against C. albicans and its infections. Moxidectin can serve as the candidate potentiator of polyenes for further clinical practice. KEY POINTS: • Moxidectin synergized with polyenes against Candida albicans. • Moxidectin activated the ergosterol biosynthesis of Candida albicans. • Moxidectin combined with polyenes to effectively combat oral candidiasis in mice.

Immunocastration is a humane alternative to surgical castration for controlling population and estrous behaviors in animals. Gonadotropin-releasing hormone (GnRH), the pivotal initiating hormone of the hormonal cascade in mammals, is the optimal target for immunocastration vaccine development. Cognate antigen-mediated cross-linking of B cell receptors (BCRs) is a strong activation signal for B cells and is facilitated by repetitive surface organizations of antigens. In this study, we describe the structure-guided design of highly immunogenic chimeric proteins with variant numbers of GnRH peptide insertion by epitope grafting. Linear B-cell epitopes of cross-reacting material 197 (CRM197) were replaced with multiple copies of GnRH peptide, and the inserts were displayed on the surface of the designs while maintaining the overall folding of CRM197. Among the seven designs, TCG13, which carries 13 copies of GnRH peptide, was the most immunogenic, and its immunocastration efficacy was evaluated in male mice. Vaccination with the BFA03-adjuvanted TCG13 induced potent humoral immunity and reduced the serum testosterone concentration in mice. It could significantly decrease sperm quality and severely impair gonadal function and fertility. These results demonstrate that CRM197 holds great value as a scaffold for epitope presentation in peptide-based vaccine development and supports TCG13 as a promising vaccine candidate for animal immunocastration. KEY POINTS: • Provide a feasible way to design chimeric immunogen targeting GnRH by epitope grafting. • CRM197 can accommodate the insertion of multiple copies of heterologous epitope peptides. • Administration with the most immunogenic design led to effective immunocastration in male mice.

Salmonella, a common pathogenic bacterium in food, can have a severe impact on food safety and consumer health. At present, Salmonella infection is controlled primarily by the use of antibiotics, which creates unsafe factors for food safety. Thus, finding a natural antibacterial agent is highly practical. In this study, resveratrol was screened from 17 kinds of polyphenols, and its inhibitory mechanism and effects on metabolites of Salmonella typhimurium were investigated to occur through cell wall and membrane damage and metabolomics analysis. The results revealed that the minimum inhibitory concentration of resveratrol against S. typhimurium was 250 μg/mL. After treatment with resveratrol, the lag period of the strain was prolonged, and the cell wall and membrane structure were destroyed. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) further confirmed that resveratrol induced damage to the cell walls and cell membrane. The metabolic profile of S. typhimurium following resveratrol treatment was analysed by gas chromatography‒mass spectrometry. In the metabolome evaluation, we screened 23 differentially abundant metabolites, including 11 upregulated and 12 downregulated metabolites. Eight metabolic pathways of S. typhimurium, including pathways important for amino acid metabolism and the tricarboxylic acid (TCA) cycle, exhibited significant changes after resveratrol treatment. The verification results of the citric acid content, cis-aconitase activity, and ATP content further revealed that the tricarboxylic acid cycle and other related metabolic pathways of S. typhimurium were affected. These results could provide a theoretical possibility for the use of resveratrol as a plant-derived bacteriostatic for food safety problems caused by S. typhimurium. KEY POINTS: • The mechanism of bacteriostasis was studied via metabolomics • Resveratrol causes the death of Salmonella by disrupting the cell wall and membrane.

Listeria monocytogenes is a major foodborne pathogen affecting developing, and developed countries. The analysis of food contact surfaces in food industries is key for better controlling this pathogen. The current study focused on the development, optimization, and evaluation of a rapid and simple method for the detection of L. monocytogenes on stainless steel surfaces, suitable for decentralized setups, taking advantage of Loop-mediated isothermal amplification (LAMP). This was accomplished using a general pre-enrichment broth (TSB), with a simple DNA extraction based on a chelating resin, and final isothermal amplification. Two different detection strategies were tested, real-time fluorescence and naked-eye colorimetric, which were evaluated after 5, 7, and 24 h of pre-enrichment. Regardless the detection chemistry selected, after 5-7 h of pre-enrichment, 10-10 CFU/cm were needed to obtain a positive result, while after 24 h, it was possible to detect concentrations below 10 CFU/cm. Within each given time, all the performance parameters calculated, relative sensitivity, specificity, and accuracy, reached values higher than 80-90%; likewise, a Cohen's k of concordance with a culture-based approach higher than 0.8. Overall, the most sensitive assay can be performed in roughly 25 h. This time-to-result outperforms commercial kits with the added value of specifically detecting L. monocytogenes instead of Listeria spp. KEY POINTS: • Real-time fluorescence and naked-eye colorimetric, were compared for the novel assay. • An LOD50 of 3.4 CFU/cm and 4.2 CFU/cm was calculated for the two assays. • Three pre-enrichment times were compared providing 24 h better results.

The current development of industrial hemp "Cannabis Sativa L." fibers for technical textiles and industrial applications requires high-quality fibers with homogeneous properties. However, several factors have been reported to influence the fibers' intrinsic properties, including a post-harvest process known as retting. This process plays a crucial role in facilitating the mechanical extraction of fibers from hemp stems. Retting involves the degradation of the amorphous components surrounding the fiber bundles enabling their decohesion from stems. Microorganisms play a central role in mediating this bioprocess. During retting, they colonize the stems' surface. Therefore, the biochemical components of plant cell wall, acting as natural binding between fibers, undergo a breakdown through the production of microbial enzymes. Although its critical role, farmers often rely on empirical retting practices, and considering various biotic and abiotic factors, resulting in fibers with heterogenous properties. These factors limit the industrial applications of hemp fibers due to their inconsistent properties. Thus, the purpose of this review is to enhance our comprehension of how retting influences the dynamics of microbial communities and, consequently, the evolution of the biochemical properties of hemp stems throughout this process. Better understanding of retting is crucial for effective process management, leading to high-value fibers. KEY POINTS: • Retting enables degradation of cell wall components, controlling fiber properties. • Microbial enzymatic activity is crucial for successful decohesion of fiber bundles. • Understanding retting mechanisms is essential for consistent fiber production.

Many relevant metabolites, as well as chemical commodities, contain at least one sulfate ester group. Consequently, biocatalytic strategies to attach sulfate to a molecule under mild conditions are of high interest. In order to expand the enzymatic toolbox available, five new arylsulfate sulfotransferases (ASSTs) were identified in this study. Overexpression in Escherichia coli and enzyme purification resulted in soluble proteins which catalyzed the sulfate transfer to an acceptor substrate using p-nitrophenyl sulfate (pNPS) as sulfate donor. Optimal reaction conditions were established with respect to temperature and pH, as well as their tolerance to organic co-solvents and melting temperature. Additionally, the kinetic parameters (V, K, and k) were determined. The substrate scope for the acceptor showed that a structurally diverse spectrum of alcohols is accepted. The substrates included phenolic alcohols with one, two, and three hydroxy groups, linear and cyclic aliphatic alcohols, and amines. The phenolic substrates were accepted reaching activities of up to 154 U/mg purified enzyme. Additionally, also the aliphatic alcohols (both linear and cyclic) were accepted at reduced activity, showing that these enzymes are not limited to phenolic alcohols. Moreover, catalytic activity was detected when using aniline as an acceptor substrate implying their ability to sulfate also amino groups. Finally, the consecutive sulfation of di- and trihydroxy compounds was observed, resulting in the detection of the corresponding disulfated molecules. KEY POINTS: • Five novel arylsulfate sulfotransferases were identified and characterized. • Accepted substrates included aromatic and aliphatic alcohols, as well as aniline. • Disulfation of di- and trihydroxy aromatic compounds was studied and confirmed.

Cattle manure or its digestate, which often contains antibiotic residues, can be used as an organic fertilizer and copper (Cu) as a fungicide in agriculture. Consequently, both antibiotics and Cu are considered soil contaminants. In this work, microcosms were performed with soil amended with either manure or digestate with Cu and an antibiotic (sulfamethoxazole, SMX) co-presence and the planting of Lactuca sativa. After the addition of the organic amendments, a prompt increase in the microbial activity and at the same time of the sul1 and intI1 genes was observed, although ARGs generally decreased over time. In the amended and spiked microcosms, the microbial community was able to remove more than 99% of SMX in 36 days and the antibiotic did not bioaccumulate in the lettuce. Interestingly, where Cu and SMX were co-present, ARGs (particularly sul2) increased, showing how copper had a strong effect on resistance persistence in the soil. Copper also had a detrimental effect on the plant-microbiome system, affecting plant biomass and microbial activity in all conditions except in a digestate presence. When adding digestate microbial activity, biodiversity and lettuce biomass increased, with or without copper present. Not only did the microbial community favour plant growth, but lettuce also positively influenced its composition by increasing bacterial diversity and classes (e.g., Alphaproteobacteria) and genera (e.g., Bacillus), thus indicating a good-quality soil. KEY POINTS: • Cattle digestate promoted the highest microbial activity, diversity, and plant growth • Cattle digestate counteracted detrimental contaminant effects • Cu presence promoted antibiotic cross-resistance in soil.

Enhancing the secretion of recombinant proteins, particularly non-enzymatic proteins that predominate in food and pharmaceutic protein products, remains a significant challenge due to limitations in high-throughput screening methods. This study addresses this bottleneck by establishing a yeast surface display system in the food-grade microorganism Kluyveromyces lactis, enabling efficient display of model target proteins on the yeast cell surface. To assess its potential as a universal high-throughput screening tool for enhanced non-enzymatic protein secretion, we evaluated the consistency between protein display levels and secretion efficiency under the influence of various genetic factors. Our results revealed a strong correlation between these two properties. Furthermore, screening in a random mutagenesis library successfully identified a mutant with improved secretion. These findings demonstrate the potential of the K. lactis surface display system as a powerful and universal tool for high-throughput screening of strains with superior non-enzymatic protein secretion capacity. We believe this study could pave the way for efficient large-scale production of heterologous food and therapeutic proteins in industries. KEY POINTS: • A YSD (yeast surface display) system was established in Kluyveromyces lactis • This system enables high-throughput screening of non-enzymatic protein secretion • This technology assists industrial production of food and therapeutic proteins.

The increasing prevalence of multidrug-resistant pathogens is a critical public health issue, necessitating the development of alternative antibacterial agents. Examples of these pathogens are methicillin-resistant Staphylococcus aureus (MRSA) and the emergence of "pan-resistant" Gram-negative strains, such as Pseudomonas aeruginosa and Acinetobacter baumannii, which occurred more recently. This review examines various emerging materials with significant antibacterial activities. Among these are nanomaterials such as quantum dots, carbon quantum dots, metal-organic frameworks (MOFs), covalent organic frameworks (COFs), and layered double hydroxides, all of which demonstrate excellent antibacterial properties. Interestingly, including antibacterial agents within the structure of these materials can help avoid bacterial resistance and improve the long-term efficacy of the materials. Additionally, the antibacterial potential of liquid solvents, including ionic liquids and both deep eutectic solvents and natural deep eutectic solvents, is explored. The review discusses the synthesis methods, advantages, and antibacterial efficacy of these new materials. By providing a comprehensive overview of these innovative materials, this review aims to contribute to the ongoing search for effective solutions to combat antibiotic resistance. Key studies demonstrating antibacterial effects against pathogens like Escherichia coli, Staphylococcus aureus, and multidrug-resistant strains are summarized. MOFs have exhibited antibacterial properties through controlled ion release and surface interactions. COFs have enhanced the efficacy of encapsulated antibiotics and displayed intrinsic antibacterial activity. Other nanomaterials, such as quantum dots, have generated reactive oxygen species, leading to microbial inactivation. This review aims to provide insights into these new classes of antibacterial materials and highlight them for addressing the global crisis of antibiotic resistance. KEY POINTS: • Nanomaterials show strong antibacterial effects against drug-resistant bacteria • Emerging solvents like ionic liquids offer novel solutions for bacterial resistance • MOFs and COFs enhance antibiotic efficacy, showing promise in combating resistance.

This study demonstrates the sustainable advancement of fermentation media by blending the organic fraction of municipal solid waste (OFMSW) with organosolv beechwood cellulose. Investigations examined the effects of enzyme dosages and OFMSW integration into organosolv beechwood cellulose on sugar yield. The findings indicate that OFMSW inclusion and Cellic® CTec3 dosage significantly influence hydrolysis across two different batches of beechwood cellulose. Experimental data showed that OFMSW inclusion levels of 35% and 45% (w/w) produced sugar levels comparable to pure beechwood cellulose, achieving 58% to 68% (w/w) saccharification with sugar concentrations of 44 to 46 g/L. This highlights OFMSW's potential as a buffer substitute during the enzymatic conversion of organosolv cellulose. The resulting sugar-rich hydrolysates, derived from OFMSW-cellulose blends and pure cellulose, were evaluated for ethanol and cell biomass production using Saccharomyces cerevisiae and Mucor indicus, yielding 30 g of ethanol/L hydrolysate. Furthermore, OFMSW inclusion in beechwood cellulose proved to be an excellent alternative to synthetic nitrogen agents for S. cerevisiae cell production, reaching 12.2 g of biomass/L and surpassing the biomass concentration from cultivation on cellulose hydrolysate with nitrogen supplementation by threefold. However, M. indicus did not grow in the OFMSW-cellulose blend, suggesting that the inhibitory compounds of OFMSW may be a bottleneck in the proposed process. The present study demonstrates the benefits of incorporating OFMSW into cellulose material, as it enhances both cost-effectiveness and sustainability. This is attributed to the natural buffering properties and nitrogen content of OFMSW, which reduces the need for synthetic agents in fermentation-based lignocellulose biorefineries. KEY POINTS: • OFMSW inclusion significantly influences beechwood cellulose saccharification. • OFMSW could be an excellent alternative for synthetic agents in biorefinery. • S. cerevisiae achieved higher biomass growth on OFMSW/cellulose mix compared to YPD.

The synthesis of nitriles is of utmost importance for preparative organic chemistry. The classical routes are often associated with disadvantages such as toxicity of the reagents and drastic conditions. The uses of enzymes like aldoxime dehydratases (Oxds) and hydroxynitrile lyases constitute attractive benign alternatives. In this review, we summarize the recent trends regarding Oxds. Thousands of oxd genes were sequenced but less than thirty Oxds were investigated on protein level. We give an overview of these Oxds, their sequence analysis, conditions required for their overexpression, and their purification and assays. We then focus on the use of Oxds especially in multistep reactions combining the chemical or chemoenzymatic synthesis of aldoximes from different starting materials with the enzymatic dehydration of aldoximes to nitriles, possibly followed by the hydration of nitriles to amides. Progress in Oxd immobilization is also highlighted. Based on data published mainly in the last 5 years, we evaluate the industrial prospects of these enzyme processes in comparison with some other innovations in nitrile synthesis. KEY POINTS: • Aldoxime dehydratases (Oxds) are promising for cyanide-free routes to nitriles • A comprehensive overview of wet-lab explored Oxds is provided • Recent trends include combining Oxds with other enzymes or chemical catalysts.

Biochemical methane potential (BMP) test is an important tool to evaluate the methane production biodegradability and toxicity of different wastes or wastewaters. This is a key parameter for assessing design and feasibility issues in the full-scale implementation of anaerobic digestion processes. A standardized and storable inoculum is the key to obtain reproducible results. In Uruguay, a local enterprise dedicated to design and install anaerobic digesters operated a lab-scale bioreactor as a source of biomass for BMP tests, using a protocol previously described. This reactor was controlled and fed with a mixture of varied organic compounds (lipids, cellulolytic wastes, proteins). Biomass was reintroduced into the reactor after BMP assays to maintain a constant volume and biomass concentration. The aim of this work was to evaluate how the microbial community evolved during this operation and the effect of storing biomass in the refrigerator. The composition of the microbial communities was analyzed by 16S rRNA amplicon sequencing using primers for Bacteria and Archaea. The methanogenic activity was determined, and the methanogens were quantified by mcrA qPCR. One sample was stored for a 5-month period in the refrigerator (4 °C); the activity and the microbial community composition were analyzed before and after storage. Results showed that applying the reported methodology, a reliable methanogenic sludge with an acceptable SMA was obtained even though the reactor suffered biomass alterations along the evaluated period. Refrigerating the acclimatized biomass for 5 months did not affect its activity nor its microbial composition according to the 16S rRNA gene sequence analysis, even though changes in the mcrA abundance were observed. KEY POINTS: • The applied methodology was successful to obtain biomass suitable to perform BMP assays. • The microbial community was resilient to external biomass addition. • Biomass storage at 4 °C for 5 months did not alter the methanogenic activity.

Xerophilic fungi occupy versatile environments owing to their rich arsenal helping them successfully adapt to water constraints as a result of low relative humidity, high-osmolarity, and high-salinity conditions. The general term xerophilic fungi relates to organisms that tolerate and/or require reduced water activity, while halophilic and osmophilic are applied to specialized groups that require high salt concentrations or increased osmotic pressure, respectively. Species belonging to the family Aspergillaceae, and especially those classified in Aspergillus subgenus Aspergillus (sections Restricti and Aspergillus) and Polypaecilum, are particularly enriched in the group of osmophilic and salt-tolerant filamentous fungi. They produce an unprecedently wide spectrum of salt tolerant enzymes including proteases, peptidases, glutaminases, γ-glutamyl transpeptidases, various glycosidases such as cellulose-decomposing and starch-degrading hydrolases, lipases, tannases, and oxidareductases. These extremophilic fungi also represent a huge untapped treasure chest of yet-to-be-discovered, highly valuable, biologically active secondary metabolites. Furthermore, these organisms are indispensable agents in decolorizing textile dyes, degrading xenobiotics and removing excess ions in high-salt environments. They could also play a role in fermentation processes at low water activity leading to the preparation of daqu, meju, and tea. Considering current and future agricultural applications, salt-tolerant and osmophilic Aspergilli may contribute to the biosolubilization of phosphate in soil and the amelioration salt stress in crops. Transgenes from halophile Aspergilli may find promising applications in the engineering of salt stress and drought-tolerant agricultural crops. Aspergilli may also spoil feed and food and raise mycotoxin concentrations above the permissible doses and, therefore, the development of novel feed and food preservation technologies against these Aspergillus spp. is also urgently needed. On the other hand, some xerophilic Aspergilli have been shown to be promising biological control agents against mites. KEY POINTS: • Salt tolerant and osmophilic Aspergilli can be found in versatile environments • These fungi are rich resources of valuable enzymes and secondary metabolites • Biotechnological and agricultural applications of these fungi are expanding.

Methods such as gas stripping and vacuum-assisted gas stripping (VAGS) result in significant removal of water from the bioreactor, thus requiring continuous water replenishment in the bioreactor. In this study, we developed a hydrophobic stainless steel meshes capable of selectively recovering concentrated ABE stream from the bioreactor during VAGS. Three stainless steel meshes with pore sizes of 180 µm, 300 µm, and 425 µm were made hydrophobic and oleophilic with zinc oxide (ZnO) and polydimethylsiloxane (PDMS). Butanol concentrations in the model solutions range from 3 to 10 g/L which mimic concentrations typically produced during batch ABE fermentation. The meshes were integrated in a 5-L bioreactor containing 2.5 L of operational ABE model solution followed by the evaluation of selective extraction of ABE from both cell-free and Clostridium beijerinckii-rich ABE model solutions. The results show that the 180-µm ZnO/PDMS-coated mesh retained 54-64% more water in the bioreactor without C. beijerinckii cells and 61-65% more water with cells compared to the uncoated mesh. Furthermore, the butanol concentration of condensates recovered with 180-µm ZnO-PDMS-coated mesh was up to 10.8-fold greater than that of uncoated counterpart. Our data demonstrate that the developed ZnO-PDMS mesh can recover high concentrations of ABE while selectively retaining water in the bioreactor. Additionally, this technology demonstrates the potential for real-time ABE recovery during the fermentation of lignocellulosic and colloidal materials, without the concern of clogging the separation system. KEY POINTS: • Hydrophobic mesh enhanced water retention in the bioreactor by up to 1.65-fold. • Butanol concentration in the collected condensate was increased by up to 10.8-fold. • Hydrophobic mesh is compatible with fermentation of lignocellulose.

Melon thrips, Thrips palmi, represent a significant threat to plants, inducing necrosis and acting as vectors for numerous plant viruses. Entomopathogenic fungi present a promising avenue for the management of melon thrips populations resistant to conventional chemical treatments. In this work, an adult colony of melon thrips was exposed to Beauveria bassiana strain JEF-350, and the ensuing transcriptional response of the infected thrips was scrutinized to elucidate their reactions during fungal pathogenesis. Utilizing Illumina sequencing, RNA samples were extracted from untreated thrips as well as from thrips continuously infected for 2 and 4 days, each with three biological replicates. While no notable alterations in gene expression were observed between the untreated control and thrips infected for 2 days, those infected for 4 days exhibited a plethora of differentially expressed genes. Specifically, in the thrips infected for the extended period, pathways associated with lysosomal function and insect hormone biosynthesis were notably repressed, while others such as serine and glycine metabolism, Toll and Imd, and circadian rhythm pathways displayed heightened activity. Noteworthy downregulation was observed in numerous lysosomal hydrolase genes encoding glycosidases, sulfatases, and lipases, particularly glycosidases. Furthermore, certain genes related to hydrolase precursors within the Golgi apparatus exhibited heightened expression levels but failed to progress toward hydrolase biosynthesis. Upstream regulation of juvenile hormone biosynthesis was augmented, yet downstream genes were significantly downregulated, leading to a disruption in juvenile hormone production. Similarly, while cytochrome P450 genes in the downstream of ecdysone biosynthesis were upregulated, expressions of cholesterol desaturase and cytochrome P450 genes in the upstream were inhibited, consequently dampening ecdysone biosynthesis. The observed differential targeting of organs or pathways by B. bassiana JEF-350, in contrast to conventional chemicals primarily affecting neurotransmission and energy production, suggests its potential efficacy in managing resistant thrips populations. Consequently, integrating JEF-350 into the chemical spray regimen or incorporating it into tank-mix formulations with chemical insecticides emerges as a pragmatic approach within the realm of integrated pest management strategies. KEY POINTS: • Beauveria treatment inhibited lysosomal function and hormone synthesis in thrips. • Thrips serine/glycine metabolism, Toll and Imd, and circadian rhythm pathways were activated. • Upstream functions of thrips hormone biosynthesis increased, while downstream functions were suppressed. • Regarding biosynthesis of metabolites, this fungus targets other pathways with resistance management.

Corpse decomposition affects soil organisms through the formation of "cadaver decomposition islands." Soil diazotrophic microbes possess essential ecological functions on nitrogen input and nutrient cycling in the terrestrial ecosystem. However, our knowledge about how soil diazotrophic communities respond to corpse decomposition is lacking. In this study, we focused on the succession patterns and biological interaction of nitrogen-fixing microorganisms during animal (Ochotona curzoniae) corpse decomposition in terrestrial ecosystems by targeting nifH gene with high-throughput sequencing. Our results revealed that corpse decomposition of pikas reduced the α diversity and significantly impacted the β diversity of diazotrophic community across different decomposition stages. The divergent succession of diazotrophic community occurred under corpse pressure. Furthermore, the relative importance of stochasticity to the community assembly was improved by corpse decomposition, while the importance decreased over decomposition time. Cadaver decay also simplified the diazotrophic networks and weakened the biological interactions among diazotrophic populations. Notably, NH-N was the most important factor affecting diazotrophic community, followed by time and total carbon. This work emphasized that corpse decomposition perhaps influences the process of biological nitrogen fixation by altering soil diazotrophic communities, which is of great significance for understanding the terrestrial ecosystems' nitrogen cycle functions. KEY POINTS: • Corpse decomposition reduced the α diversity of diazotrophic community. • Corpse decomposition improved the stochasticity of diazotrophic community assembly. • Corpse decomposition weakened the interactions among diazotrophic populations.

The regulatory mechanisms governing expression of genes encoding lignin-modifying enzymes (LME) in white-rot fungi remain largely unexplored. Although molecular cloning has identified CCAAT-boxes frequently located 5'-upstream of these genes, their role in transcriptional regulation is not well understood. This study examines the function of hap2, a gene encoding a hypothetical protein homologous to a component of the CCAAT-binding Hap complex, in the white-rot fungus Pleurotus ostreatus. Deletion of hap2 resulted in significantly reduced Mn-dependent peroxidase activity and lignin-degrading capacity compared to the parental strain 20b grown on beech wood sawdust (BWS) medium. Real-time PCR revealed that vp2 transcript levels were significantly lower in hap2 deletants than in 20b grown when cultured on the three solid media consisting of BWS, holocellulose, or Avicel, but not on yeast-malt-glucose (YMG) agar plates. Additionally, glutathione S-transferase (GST) pulldown and electrophoretic mobility shift assays demonstrated that recombinant P. ostreatus Hap2, Hap3, and Hap5 expressed in Escherichia coli form a complex capable of binding to the CCAAT sequence 5'-upstream of vp2 in vitro. These results suggest that Hap2, as part of the CCAAT-binding complex, is essential for transcriptional upregulation of vp2 in P. ostreatus growing on lignocellulosic substrates. KEY POINTS: • P. ostreatus hap2 deletants were generated. • Lignin-degrading capacity was significantly reduced in the hap2 deletants. • vp2 was significantly downregulated upon hap2 deletion.

Healtcare-associated infections have increased due to the development of antimicrobial resistance (AMR) of Gram-negative pathogens (GNPs) and the development of outbreacks over the past two decades. In this work, we investigated how exposure to positive electric pulses affects the growth characteristics of Klebsiella pneumonia (K. pneumonia), a common cause of pneumonia. We explored the impact of varying exposure frequencies (0.2-2 Hz) and time (15-90 min, at resonance frequency) on bioelectric signals produced during cell division, biofilm formation, and bacterial antibiotic susceptibility. Our research found that an extremely low-frequency pulsed electric field (ELF-PEF) significantly inhibited K. pneumonia growth. Specifically, exposure to 0.8 Hz for one hour increased the antibiotic susceptibility of K. pneumonia to inhibitors of cell wall formation, proteins, β-lactamase, DNA, and other substances. We also noticed a notable decrease in K. pneumonia biofilm development exposed to ELF-PEF. Our results suggest that the interaction of K. pneumonia cells with ELF-PEF at the specified frequency and time alters cellular activity and bacterial structure. This technique may be used in the future to treat K. pneumonia infections both in vitro and in vivo.

The increasing demand for sustainable food production has driven a surge in the use and commercialization of biological inputs, including biofertilizers. In this context, biofertilizers offer potential benefits for nutrient use efficiency, crop yield and sustainability. However, inconsistent definition of the term "biofertilizer" and regulations, particularly in the USA, hinder market growth and consumer confidence. While the European Union, and countries like Brazil, India, and China have made progress in this area, the USA market, projected to exceed $1 billion by 2029, lacks clear guidelines for biofertilizer production and sale. The USA market is dominated by Rhizobium genus, Mycorrhizae fungi, and Azospirillum species and based products targeting various crops. Although there is a growing and promising market for the use of biofertilizers, there are still many challenges to overcome, and to fully realize the potential of biofertilizers, future research should focus on modes of action, specific claims, and robust regulations that must be established. KEY POINTS: • The term "biofertilizer" lacks a universally accepted definition • It is necessary establishing a national regulation for biofertilizers in the USA • The biofertilizer market is growing fast and the biggest one is in America.

In the first days of life, the newborns' intestinal microbiota develops simultaneously with the intestinal gut barrier and follows intestinal immunity. The mode of delivery shows significant impact on microbial development and, thus, the initiation of the tryptophan catabolism pathway. Further antibiotics (ATB) treatment of mothers before or during delivery affects the microbial and tryptophan metabolite composition of stool of the caesarean- and vaginal-delivered newborns. The determination of microbiome and levels of tryptophan microbial metabolites in meconium and stool can characterize intestinal colonization of a newborn. From 134 samples from the Central European Longitudinal Studies of Parents and Children: The Next Generation (CELSPAC: TNG) cohort study, 16S rRNA gene sequencing was performed, and microbial tryptophan metabolites were quantified using ultra-high-performance liquid chromatography with triple-quadrupole mass spectrometry. Microbial diversity and concentrations of tryptophan metabolites were significantly higher in stool compared to meconium. Treatment of mothers with ATB before or during delivery affects metabolite composition and microbial diversity in stool of vaginal- and caesarean-delivered newborns. Correlation of microbial and metabolite composition shows significant positive correlations of indol-3-lactic acid, N-acetyl-tryptophan and indol-3-acetic acid with Bifidobacterium, Bacteroides and Peptoclostridium. The positive effect of vaginal delivery on newborns' microbiome development is degraded when mother is treated with ATB before or during delivery. KEY POINTS: • Antibiotic treatment diminishes the positive effects of vaginal delivery. • Antibiotic treatment affects metabolite and microbial composition in newborns. • Bifidobacterium and Peptoclostridium could be the producer of indole-lactic acid.

The unexpected monkeypox (Mpox) outbreak has been reported in many non-endemic countries and regions since May 2022. The mutant strains of Mpox virus (MPXV) were found with higher infectivity and greater capability for sustained human-to-human transmission, posing a significant public health threat. MPXV A29L, a protein homolog of vaccinia virus (VACV) A27L, plays an important role in viral attachment to host cell membranes. Therefore, MPXV A29L is considered the diagnostic target and the potential vaccine candidate for eliciting neutralizing antibodies and protective immune responses. In response to the escalating Mpox outbreak, three monoclonal antibodies (mAbs) (2-9B, 3-8G, and 2-5H) targeting the different domains of MPXV A29L have been developed in the study. Among them, 2-5H is highly specific for MPXV A29L without exhibiting cross-reactivity with VACV A27L. The antibody pairing composed of 2-5H and 3-8G has been developed as the lateral flow immunochromatographic assay for specific detection of MPXV A29L. However, these three mAbs were unable to inhibit A29L binding to heparin column or prevent MPXV infection in the neutralization test assays. The results of the serological assays using the truncated A29L fragments as the antigens showed that the Mpox patient sera contained significantly lower levels of antibodies targeting the N-terminal 1-34 residues of A29L, suggesting that the N-terminal portion of A29L is less immunogenic upon natural infection. KEY POINTS: • MAbs 2-9B, 3-8G, and 2-5H neither interrupted A29L binding to heparin nor neutralized MPXV. • The LFIA composed of 3-8G and 2-5H can specifically distinguish MPXV A29L from VACV A27L. • Mpox patient sera contained lower levels of antibodies targeting the N-terminal portion of A29L.