The oxyR negatively regulates processing stress resistance in Escherichia coli O157:H7 by reducing ROS scavenging capacity.

BbCFEM7 contributes to the virulence of entomopathogenic fungi by competing for iron with Enterococcus mundtii.

Metabolic-inhibitor profiling links phenotype and transcriptome of Lachancea thermotolerans to wine fermentation chemistry.

Gc glycoprotein trimer vaccine elicits robust neutralizing antibodies against severe fever with thrombocytopenia syndrome virus in mice.

Lumpy Skin Disease (LSD) is an emerging transboundary poxviral infection affecting cattle and buffaloes, caused by the Lumpy Skin Disease Virus (LSDV), a member of the Capripoxvirus genus. Characterized by fever, nodular dermatitis, lymphadenopathy, and production loss, the disease has evolved from a regionally confined threat in Africa to a global epizootic. While mortality remains below 5%, morbidity can reach 100% in affected herds, leading to severe economic disruption in livestock-dependent economies. Between 2005 and 2020, over 41,000 outbreaks were reported globally, nearly 30,000 in Africa, 8,800 in Asia, and 2,400 in Europe. The 2022 outbreak in India alone affected 2.4million cattle and led to over 110,000 deaths, with estimated losses exceeding approximately $60million USD. This review consolidates the current understanding of LSD's molecular virology, transmission dynamics, and global distribution. Mechanisms of transmission through direct contact, iatrogenic practices, and vector-mediated spread via mechanical and biological arthropods are reviewed in detail. Special emphasis is placed on mechanical transmission via Aedes aegypti, Stomoxys calcitrans, and Rhipicephalus appendiculatus, as well as the emergence of recombinant LSDV strains resulting from interactions between vaccine and wild strains. Molecular diagnostics (PCR, LAMP, NGS) and existing control measures, including live-attenuated and homologous vaccines, are critically evaluated. The review highlights gaps in vector surveillance, cold-chain infrastructure, and diagnostic reach, especially in developing nations. It underscores the urgent need for region-specific vaccine strategies and integrated vector control. Addressing this neglected livestock disease is crucial not only for animal health but also for rural livelihoods, food security, and economic resilience.

The Amazon biome hosts a rich fungal biodiversity; however, the biotechnological potential of its macrofungi remains largely underexplored. This study evaluates and compares the mycelial growth and protease production of a wild Amazonian isolate of Pleurotus ostreatus (474) with two commercial strains (542 and 885) to identify unique biotechnological profiles. The strains were cultivated in nine different culture media, and their mycelial growth rates and major proteolytic activities were systematically measured. The wild Amazonian strain (474) exhibited significantly superior mycelial growth, reaching maximum growth on Oat Flakes Agar (OFA) within four days. In contrast, the commercial strains acted as specialized enzyme producers; strain 885 showed the highest cysteine protease activity (8.05 ± 0.15 UA/mL) on Malt Yeast Sucrose Agar (MYSA), while strain 542 exhibited the highest total protease (77.53 ± 0.67 UA/mL) and fibrinolytic activity (6.45 ± 0.00mm²) on Malt Extract Agar (MEA). These results reveal a clear biotechnological trade-off, with the Amazonian isolate excelling in biomass accumulation and the commercial strains optimized for enzyme production. This study highlights the Amazonian strain as a promising candidate for rapid mycoprotein production and underscores the Amazon as a valuable source for expanding the functional diversity of P. ostreatus.

Vibrio parahaemolyticus outer membrane porin Vpa0810 regulates its biofilm formation and plays a vital role in its stresses tolerance.

Silver nanoparticles resistance in Listeria monocytogenes: morphologic, virulence and cellular response.

UV irradiation is known to enhance the activity of keratinases and catalase in microbes. This study aimed to evaluate the decomposing capabilities of wild and UV-irradiated Bacillus subtilis strains. Therefore, wild and UV-irradiated strains (0, 60, 150 and 240 min) were allowed to degrade poultry feathers for 0, 30 and 60 days. The biodegraded products were used as supplements (0 and 3 g/kg soil) for cotton. The best-performing biocompost was chosen based on the correlation between its physical and chemical properties. Selected biocompost (60 days matured by 150 min of UV-irradiated B. subtilis) was applied as a rooting medium to stressed cotton (control and 50 mg K2Cr2O7/kg soil). Chromium (Cr) stress negatively affected growth, fiber and oil quality in untreated and feather-supplemented plants. B. subtilis-degraded biocomposts improved germination rate, index and percentage; leaf numbers, branches, chlorophyll a/b ratio, carotenoids, soluble proteins, amino acids and ascorbic acids; fiber elasticity, fiber uniformity index (FUI) and boll weight; and reduced coefficient of variation (CVt), fiber micronaire, malondialdehyde (MDA) and H2O2. Biocompost prepared from UV-irradiated B. subtilis strain (150 min) was better in terms of carbon/ nitrogen (C/N) ratio of compost, shoot fresh weight, germination percentage, shoot length, dry weight, chlorophyll a/b ratio, carotenoids, boll weight, seed number and unsaturated fatty acids. In summary, to grow cotton in Cr-stressed areas, feathers degraded by B. subtilis can serve as a beneficial, eco-friendly biocompost. UV irradiation can additionally enhance the efficiency of B. subtilis.

Escherichia coli relies on Dcu transporters to facilitate succinate transport during fermentation, with DcuD being one of three members of this transporter family primarily involved in C4 -dicarboxylate exchange. This study investigated the role of amino acid mutations in E.coli DcuD transporters in proton flux at pH 5.5. In this study proton flux (JH+) was measured in E. coli BW25113 wild type strain and dcuD mutants with specific amino acid defects. JH+ was determined using selective pH electrode. To evaluate the contribution of FOF1-ATPase, 0.2 mM N,N-dicyclohexylcarbodiimide (DCCD) was used. When glucose was added in E. coli BW25113 assay total JH+ was ~0.81 mmol min-1 per 109 cells in 1 unit and when cells were treated with DCCD JH+ was ~0.11 mmol min-1 per 109 cells. In mutant with defect of Arg67 total JH+ was 1.9-fold lower, compared to the wild type, and the DCCD has effect, thus contribution of FOF1-ATPase to the proton export pathway has role. In mutant with defect in Glut64, the total JH+ was similar to Arg67. In mutant with defect of Glut324 total JH+ was ~2.7-fold lower compared to wild type. However, in mutant with defect of Lys328 no significant differences were observed compared to wild type. These findings suggest that specific amino acids within the DcuD transporter influence proton flux mechanisms. Overall, the results provide insights into the functional roles of key amino acids in DcuD-mediated proton transport and proton efflux is primarily associated with of FOF1-ATPase.

Toxoplasmosis in South America: a hybridization-driven disease burden?

Nickel (Ni) contamination, primarily caused by industrial processes such as electroplating, battery manufacturing, and automotive production, poses a serious and persistent environmental threat. Kluyvera cryocrescens M7, a naturally Ni-resistant bacterium, was selected for genetic improvement to enhance its Ni bioremediation capacity. To the best of our knowledge, no studies have reported genetic improvement of Kluyvera species aimed at enhancing Ni removal. In this study, random chemical mutagenesis using ethyl methane sulfonate (EMS) was employed to generate mutants with improved metal uptake. The wild-type K. cryocrescens M7 strain exhibited a maximum Ni removal efficiency of 48.41% and a specific uptake capacity of 129.58mg/g at 100 ppm Ni after 48h by Flame atomic absorption spectrophotometer (FAAS). In comparison, EMS-derived mutants 2, 3, and 16 demonstrated significantly higher removal efficiencies- 97.43%, 94.67%, and 95.47% and uptake capacities of 213.15mg/g, 182.12mg/g, and 183.49mg/g, respectively. Mutant 2 also showed maximum removal efficiency of 71.43% in case of electroplating industrial wastewater, maintaining strong efficacy despite complex conditions. The enhanced accumulation of Ni ions in mutant 2 as compared to the wild strain was also validated by Fourier Transform-Infrared (FTIR) spectroscopy. To understand the genetic basis of this improvement, two key Ni transport-related genes- hoxN (influx transporter) and rcnA (efflux protein)-along with their promoter regions were amplified and sequenced. Sequence analysis revealed that the wild-type strain had mismatches in the - 10 and - 35 elements compared to E. coli consensus sequences. The mutants showed improved hoxN promoter alignment and greater divergence in the rcnA promoter, suggesting enhanced influx and reduced efflux. These regulatory changes were supported by SDS-PAGE analysis showing increased HoxN and decreased RcnA expression. This study highlights EMS-induced mutagenesis as a viable strategy to enhance Ni bioremediation in K. cryocrescens through modulation of metal transporter gene expression.

Isolation of wild fermentative yeast strains from native fruits of Misiones province, Argentina

Chemical stimuli, including odorants and tastants, provide information about food availability and allow animals to avoid harmful environments. Over six decades of research using primarily one laboratory-adapted strain of the nematode Caenorhabditis elegans has yielded a wealth of information about how this animal senses and responds to chemical cues to survive. However, it was not known whether the chemosensory behavioral profile of this strain (named N2) is representative of the species. Using a collection of hundreds of wild C. elegans strains collected from around the globe, we assessed their abilities to respond to three aversive stimuli (the bitter tastant quinine, the heavy metal copper, and the detergent SDS) in a laboratory setting and found ∼10-20 fold differences in response sensitivities among the strains. Further, response sensitivities to one stimulus were largely uncoupled from responses to the other stimuli and uncorrelated with the geographical locations from which the wild strains were collected. Using genome-wide association studies, we identified unique regions significantly correlated with different responses to each stimulus. Near-isogenic lines were created to confirm the effects of two genomic regions on differential avoidance behavior to the bitter tastant quinine. Combined, we report remarkable natural variation in chemosensory behavioral responses among wild C. elegans strains and describe two new quantitative trait loci associated with decreased response sensitivity to quinine.

Whereas sanitizing wipes are among the strategies for combatting COVID-19, there are growing concerns concerning their disposal, due to majority of them being made of non-biodegradable fibres. Additionally, majority of the sanitizing solutions used are associated with irritations and some are carcinogenic. In this study, banana wipes, impregnated with an organic antimicrobial formulation were developed to counter the unbiodegradable wipes made of synthetic fibres and impregnated with toxic antimicrobial formulations. A spunlaced non-woven fabric made from 100% banana fibres was impregnated with a commercial formulation containing essential oils from lemon, eucalyptus, cedar and orange. The impregnated banana fabric wipe exhibited antimicrobial activity against all tested bacterial strains, including Escherichia coli (both ATCC 25,922 and the wild strain), Staphylococcus aureus (both ATCC 25,923 and the wild strain), and Pseudomonas aeruginosa (both ATCC 27,853 and the wild strain), with inhibition zones ranging from 10.00 ± 1.00 mm to 13.67 ± 1.16 mm, compared to the standard 14.00 mm. Furthermore, the mechanical properties of the fabric showed that the tensile strength in the wet state increased by 4.29% and 20.41% in both the machine and cross directions respectively. Given that synthetic fibres are used in wipes to achieve a high wet tensile strength since most cellulosic fibres become weaker and disintegrate when wet, it can be concluded that banana fibres can be effectively used in wipes application given that they are biodegradable and are stronger when wet.

Simple SummaryThe reproductive capacity of parasitoid wasps during their lifetime plays a crucial role in understanding their potential as biocontrol agents and the host–parasitoid dynamics. An interesting system to study involves the Southeast Asia-native parasitoid Diachasmimorpha longicaudata and its host Ceratitis capitata, commonly known as the Mediterranean fruit fly or medfly, which is a serious invasive fruit fly pest in Argentina. This study compared reproductive parameters of two parasitoid population lines reared at the biofactory San Juan on different medfly strains. One line was mass-reared on medfly larvae of a genetic sexing strain (=Dl(Cc-tsl)) and the other on larvae of a wild biparental medfly strain (=Dl(Cc-bip)). The goal was to provide information for improving parasitoid mass production and evaluating its performance under natural conditions. For this, laboratory and semi-field cage trials were conducted at the San Juan Biofactory. Firstly, laboratory trials showed that Dl(Cc-bip) females displayed higher reproductive and population rates than those of Dl(Cc-tsl) females. Secondly, semi-field cage trials revealed that females of both Dl(Cc-bip) and Dl(Cc-tsl) had similar and high reproductive potential in late spring and summer, when environmental conditions are temperate–warm. However, unlike Dl(Cc-tsl) females, Dl(Cc-bip) females were reproductively active in early autumn, albeit at very low rates due to colder environmental conditions. The current study provides novel data to improve the productivity of D. longicaudata mass rearing and to achieve the most effective medfly control through parasitoid releases in the semi-arid, fruit-growing areas of Argentina.Ceratitis capitata (Wiedemann) or medfly is a polyphagous pest of fruit crops worldwide. The Asian-native larval parasitoid Diachasmimorpha longicaudata (Ashmead) is mass-reared at the San Juan Biofactory and is currently released for medfly control in Argentina. Information on parasitoid survival, reproduction, and population growth parameters is critical for optimizing the mass-rearing process and successfully achieving large-scale release. This study provides a first-time insight into the demography of two population lines of D. longicaudata: one mass-reared on medfly larvae of the Vienna-8 temperature-sensitive lethal genetic sexing strain and the other on larvae of the wild biparental medfly strain. The aim was to compare both parasitoid populations to improve mass-rearing quality and to assess performance on medfly in a semi-arid environment, typical of Argentina’s central-western fruit-growing region. Tests were performed under laboratory and non-controlled environmental conditions in semi-field cages during three seasons. Dl(Cc-bip) females exhibited higher reproductive potential than did Dl(Cc-tsl) females under lab conditions. However, both Dl(Cc-bip) and Dl(Cc-tsl) were found to be similar high-quality females with high population growth rates in warm–temperate seasons, i.e., late spring and summer. Dl(Cc-bip) females were only able to sustain low reproductive rates in early autumn, a colder season. These results are useful for improving the parasitoid mass production at the San Juan Biofactory and redesigning parasitoid release schedules in Argentina’s irrigated, semi-arid, fruit-growing regions.

Abstract Campylobacter jejuni (Cj) is a leading cause of foodborne illness globally, often linked to consumption of poultry. Unfortunately, current strategies applied by industry to control Cj in poultry have had limited success. In this regard, understanding the humoral immune response and associated changes in serum biochemistry to C. jejuni colonization in broiler chickens is essential for developing effective vaccines, as biochemical markers provide insights into metabolic and inflammatory responses that may influence immunity and overall health. In this study, ten day-of-hatch chickens were used to assess maternal immunity (cecal mucus, blood, and yolk sac serum), and the cecal contents were analyzed for the presence of Cj. Additionally, 56 day-of-hatch chicks were randomly divided into eight treatment groups (n=7 birds/treatment), including a negative control (NC), and allocated to their respective pens. On days 3 and 4, birds were orally gavaged with 0.25 mL of vehicle (NC) or wild strains K1, K5, K6, S1, S3, S4, or 6-strain cocktail for respective groups (~1×107 CFU/mL). On day 14, samples were collected for microbiological (cecal contents), immunological (blood and cecal contents), and serum chemistry (blood) analyses. Cecal contents were diluted and plated on Campylobacter line agar plates to enumerate Cj. Blood, yolk sac, and cecal contents were processed to extract serum and mucus. Indirect ELISA was performed to determine anti-Cj IgM, IgY, and IgA levels. Blood serum samples were analyzed using Avian rotors on MicroChem II (MicroVet Diagnostics) equipment [total protein and fractions, liver enzymes (ALT, AST, TBA, TB, and GGT), creatinine kinase, uric acid, glucose, cholesterol, calcium, phosphorus, potassium, and sodium]. All the data were analyzed using one-way ANOVA followed by Dunnett’s post hoc comparison in GraphPad Prism 10 Software. P-value< 0.05 was considered significant. Microbiology analysis confirmed Cj colonization in all challenged groups except the negative control. Immunological analysis showed high titers of anti-Cj IgY in the yolk sac and blood serum, and anti-Cj IgA in the cecal mucus of day-of-hatch birds, strongly suggesting maternal immunity transference. Additionally, anti-Cj IgM levels were higher in all day 14 birds compared to day-of-hatch chickens, with a significant increase in all the K strains and the cocktail group, suggesting the development of an anti-Cj humoral immune response. Serum biochemistry results showed that wildtype strain S3 presented significantly higher Albumin:Globulin ratio, glucose, and cholesterol concentration than the negative control, suggesting a better nutritional status. All S strains presented an average lower globulin concentration than the negative control, suggesting a lower inflammatory response. The observed changes in serum biochemistry suggest potential markers for nutritional status and inflammatory response. In conclusion, our study found that C. jejuni induces a humoral immune response suitable for vertical transfer of immunity, providing a foundation for further C. jejuni vaccine studies.

The potential role of Staphylococcal enterotoxin C and TSST-1 in the infection of bovine mammary epithelial cells.

Alternaria radicina xylanase is required for the occurrence of carrot black rot disease.

Polydextrose (PDX), as a prebiotic, is an extensively branched glucose polymer that can promote the growth of beneficial bacteria in the gut. Recent research indicates that PDX regulates intestinal function and supports immune balance, which helps to protect the gut from pathogenic bacteria. However, scarce research has been found that PDX prevents the host infection through the direct effects on the pathogen. In this study, we developed a mouse model infected with Klebsiella pneumoniae by pretreating with PDX, assessed the effect of PDX on K. pneumoniae acute infection in mice, and explored its potential mechanisms. We developed a mouse model that is infected with K. pneumoniae by pretreating with PDX. Colony counting quantified the K. pneumoniae bacterial load in the parenchymal organs of mice. A scanning electron microscope was used to investigate the morphological characteristics of K. pneumoniae. The expression level of TamA (translocation and assembly module A) was detected by reverse transcription-polymerase chain reaction (RT-PCR) and western blotting. The CRISPR-Cas9 technique was applied to construct the tamA mutant strains (ΔtamA) and the tamA complement strain (C-ΔtamA). The biofilm formation capacity was evaluated by the crystal violet assay. The capsule production was quantified by measuring uronic acid content. In the PDX pretreated model, PDX did not alter the growth characteristics and morphological structure of K. pneumoniae. However, it significantly reduces the load of K. pneumoniae in the lung, liver, spleen, and intestinal tract of mice, which is related to inhibiting the expression of the outer membrane TamA protein by PDX. In an in vitro study, the results indicated that deletion of tamA significantly inhibited capsule production and biofilm formation of K. pneumoniae, weakened interspecific and intraspecific competitive abilities with other members of the Enterobacteriaceae family, and reduced the adhesion ability to Caco-2 and murine lung epithelial (MLE) cells. Compared with the wild strain, PDX treatment and the deletion of tamA inhibit the expression of adhesion factors (including FimH, FimC, FimD, and MrkD) and the capsule synthesis genes (including galF, wzi, and manC) in K. pneumoniae. PDX can prevent the infection of K. pneumoniae in mice. The potential mechanism may involve downregulating TamA expression and inhibiting adhesion-related molecules. Therefore, PDX can serve as a potential prebiotic to reduce K. pneumoniae infections in both humans and animals.IMPORTANCEOur findings revealed that polydextrose (PDX) could significantly reduce the load of Klebsiella pneumoniae in the lung, liver, spleen, and intestinal tract of mice. The potential mechanism is related to inhibiting the expression of the outer membrane TamA protein by PDX. The deletion of tamA significantly inhibited the capsule production and biofilm formation of K. pneumoniae, weakened the interspecific and intraspecific competitiveness ability with other members of the Enterobacteriaceae family, and reduced the adhesion ability to Caco-2 and MLE cells. Our data suggest that PDX may act as a prebiotic to reduce K. pneumoniae infections in humans and animals.