Microbiol. Res., Volume 15, Issue 3 (September 2024) – 60 articles

This study provides a preliminary background for the development of a viral vector vaccine for the dengue virus using genetic material encoded by dengue envelope ferritin nanoparticles. Adenoviruses were generated for the recombinant envelope of dengue virus 2 (DENV2) and the envelope human ferritin heavy chain using a two-vector adenovirus system. The primary immunostimulatory activity of the two viruses was analyzed in mice to determine the effect of envelope ferritin nanoparticles. Transfection of a shuttle vector delivered the target gene and packaging vector carrying the packaging signal, and recombinant adenoviruses (rAds) were generated and purified using an ultracentrifugation method. Transduction efficiencies of the generated adenoviruses were confirmed in A549 cells. Purified adenoviruses (8 × 10⁶ PFU/mL) were immunized intramuscularly into 6 weeks old BALB/c mice. Subsequently, the DENV2-specific IgG titer was evaluated 1 and 4 weeks after immunization. Envelope ferritin-immunized mice showed a significant IgG response compared to envelope-only immunized mice at 1 and 4 weeks after immunization, revealing the persistence of the dengue virus-specific IgG response. This method demonstrated the capability of the viral vector vaccine to be used as a carrier for ferritin nanoparticles, instead of direct immunization with ferritin nanoparticles. Full article

In rice, symbiotic N₂ fixation via nodule bacteroids does not take place naturally. Although N₂ fixation by endophytic and associative diazotrophs has been reported in rice, the main organs and seasonal regulation for the N₂ fixation have not been elucidated. In this study, seasonal changes in nitrogenase (acetylene reduction) activity and carbohydrate contents in elongated culm (EC), unelongated stem (US), and crown root (CR) were investigated in manure compost (MC)- and chemical fertilizer (CF)-applied rice. Nitrogenase activity increased after rooting (June) and reached the highest activity in US of MC-applied rice at panicle initiation (August). The sucrose content in EC continued to increase after rooting regardless of the applied materials, whereas the glucose content in US increased after rooting only in CF-applied rice, suggesting higher consumption of glucose in US of MC-applied rice. There were significant differences among bacterial microbiota in EC, US, and CR at panicle initiation. In addition, Clostridia class anaerobes were more abundant in US of MC-applied rice than in EC and CR of MC-applied rice. Such difference was not observed in US of CF-applied rice. These results suggest the suitability of US of MC-applied rice at panicle initiation as a site of N₂ fixation under anaerobic conditions. Full article

Pseudocercospora (previously Mycosphaerella) fijiensis is a hemibiotroph fungus and the causal agent of black Sigatoka disease, one of the most significant threats to banana production worldwide. Only a few genomics reports have paid any attention to effector proteins, which are key players in pathogenicity. These reports focus on canonical effectors: small secreted proteins, rich in cysteines, containing a signal peptide and no transmembrane domain. Thus, bias in previous reports has resulted in the non-canonical effectors being, in effect, excluded from the discussion of effectors in P. fijiensis pathogenicity. Here, using WideEffHunter and EffHunter, bioinformatic tools which identify non-canonical and canonical effectors, respectively, we predict, for the first time, the full effectorome of P. fijiensis. This complete effectorome comprises 5179 proteins: 240 canonical and 4939 non-canonical effectors. Protein families related to key functions of the hemibiotrophic lifestyle, such as Salicylate hydroxylase and Isochorismatase, are widely represented families of effectors in the P. fijiensis genome. An analysis of the gene distribution in core and dispensable scaffolds of both classes of effectors revealed a novel genomic structure of the effectorome. The majority of the effectors (canonical and non-canonical) were found to be harbored in the core scaffolds, while dispensable scaffolds harbored less than 10% of the effectors, all of which were non-canonical. Additionally, we found the motifs RXLR, YFWxC, LysM, EAR, [Li]xAR, PDI, CRN, and ToxA in the effectors of P. fijiensis. This novel genomic structure of effectors (more enriched in the core than in the dispensable genome), as well as the occurrence of effector motifs which were also observed in four other fungi, evidences that these phenomena are not unique to P. fijiensis; rather, they are widely occurring characteristics of effectors in other fungi. Full article

Moringa oleifera Lam. (moringa) is a plant native to India, used as a nutritional and medicinal supplement in many cultures around the world. Moringa has been linked to maintaining metabolic homeostasis and is often marketed as a weight loss supplement and a potential remedy for diseases such as diabetes. Here, we investigate how moringa, a ‘superfood’ with predicted protective effects against chronic diseases such as diabetes, influences the nutritional physiology and microbiome composition of the fruit fly Drosophila melanogaster. We administered moringa as a dietary supplement to Drosophila, and quantified key nutritional indices: glucose, triacylglyceride, and protein levels, and fly weight. We showed that dietary moringa supplementation significantly reduced fly glucose levels by up to ~30% and resulted in substantial restructuring of Drosophila microbiota composition, altering both gut and intracellular bacterial populations. The effect of moringa on fly glucose levels is specific because other nutritional indices, namely, triacylglyceride and protein levels and fly weight, were not significantly affected by dietary moringa supplementation. This study highlights the importance of moringa as a modulator of host glucose metabolism. Full article

Microbial electrochemical cells (MxCs) offer a sustainable approach for wastewater treatment and energy recovery by harnessing the electroactive properties of microorganisms. This study explores the enrichment of Geobacter species on anode biofilms in single-(S-MxCs) and double-chambered (D-MxCs) MxCs, using domestic wastewater without an external anode potential. Stable current densities were achieved within 10 days for S-MxCs (9.52 ± 0.8 A/m²) and 14 days for D-MxCs (4.28 ± 0.9 A/m²), with S-MxCs showing a superior electrochemical performance. Hydrogen production rates were higher in D-MxCs (14.93 ± 0.66 mmol H₂/L/day) compared to S-MxCs (9.46 ± 0.8 mmol H₂/L/day), with cumulative production rates of 12.9 ± 1.3 mmol H₂/g COD and 6.48 ± 1.4 mmol H₂/g COD, respectively. Cyclic voltammetry confirmed enhanced bioelectrocatalytic activity in S-MxCs, while SEM imaging showed denser biofilms on S-MxC anodes. The novelty of this study lies in its demonstration of efficient biofilm development and microbial community resilience under non-potentialized conditions, providing insights that advance the practical application of MxCs in environmental biotechnology. Full article

Helicobacter pylori is a human pathogen bacterium associated with gastritis, peptic ulcer, and gastric cancer. It can be identified through the 16S rRNA gene and characterized through cagA and vacA virulence genes. Clinical cultures of H. pylori were isolated and identified from human stomach biopsies. The isolates were characterized according to their colonial and microscopic morphology, and molecular genotyping was conducted to determine the bacterial virulence. A phylogenetic analysis of the 16S rRNA gene sequencing was performed. In addition, multilocus sequence typing analysis was performed to determine the phylogeographic nature of the isolated strains. Three bacterial isolates were selected from 22 gastric biopsies, identified as H. pylori through colonial morphology, Gram staining, urease, catalase, and oxidase tests and identification of the ureC gene through end-point PCR. Amplification of 16S rRNA, urea, and tonB genes was performed, as well. Differences between the cagA and vacA genotypes were determined among the isolates. The phylogenetic analysis confirmed the identity of the three isolates as the specie Helicobacter pylori. Different genotypes were obtained for each H. pylori strain, and all the clinical isolates showed the vacA s2/m2 genotype, indicating an absence of the VacA cytotoxin. Only HCGDL-MR01 is a cagA gene carrier with a greater risk to develop a serious disease, such as stomach cancer and peptic ulcer. The multilocus sequence typing placed all the strains within the hpEurope population structure. Full article

In 2018/2019, two large Guillain–Barré Syndrome (GBS) outbreaks took place in Peru. Here, we report a comprehensive analysis of biological samples from GBS patients from the 2019 outbreak. We applied metagenomic, microbiologic, and serological analyses to different biological samples collected from GBS patients. Further phenotypic and genomic characterization was conducted on Campylobacter jejuni isolates from GBS samples. Microbiologic and metagenomic analyses revealed several patients with multiple co-infections, yet no common infectious agents were found other than C. jejuni. Four C. jejuni isolates were isolated from rectal swabs. Twenty-one patients had detectable IgG serum antibodies related to C. jejuni, of whom seven had IgM antibodies. Genomic analyses showed that these four strains were clonal (ST2993) and contained the class A lipooligosaccharide biosynthesis locus. These results further support the idea that that C. jejuni is the etiological agent that triggered the GBS outbreak in Peru in 2019 and that the strains are not restricted to Peru, hence could be regarded as a broad public health concern. Furthermore, though we cannot delineate the role played by co-infections in GBS development, results obtained herein highlight metagenomic analysis as a potential new tool for depicting a yet unknown area of research in GBS. Full article

Antibiotics like colistin can save patients infected with carbapenem-resistant Pseudomonas aeruginosa. However, patients can succumb to such infections even if they undergo colistin therapy. This prompted us to investigate the probable antimicrobial resistance mechanisms and virulence determinants involved in colistin- and carbapenem-resistant P. aeruginosa (CCRPA). Of the 448 P. aeruginosa clinical strains, 19 isolates were resistant to both colistin and carbapenem. Carbapenemases and efflux pump encoding genes were assessed by multiplex PCR and qPCR, respectively. blaVIM was detected among six CCRPA isolates and blaIMP in one strain. The expression levels of pmrA and phoP, as well as pmrB genes and their association with colistin resistance, were assessed by qPCR and semi-quantitate PCR, respectively. pmrA and phoP genes were significantly enhanced in three and nine CCRPA isolates, respectively. We also phenotypically evaluated biofilms, pyocyanin, and alginate production among CCRPA strains. Alginate production was observed in 15 isolates, followed by biofilm (n = 8) and pyocyanin (n = 5). Our results highlighted the coexistence of colistin and carbapenem resistance and biofilm formation among clinical isolates of CCRPA. Further studies are required to trace the source and the origin of colistin and carbapenem resistance in this specific environment. Full article

Toxoplasmosis, caused by Toxoplasma gondii, poses a significant threat to sheep flocks, affecting reproductive performance and meat quality, and leading to economic losses. This study aimed to evaluate the correlation between anti-T. gondii IgG antibodies in the serum and colostrum of naturally infected ewes and to assess passive immunity in newborn lambs. Blood and colostrum samples were collected from 162 ewes and 182 lambs across 20 sheep farms in Paraíba, Brazil. Samples were tested for anti-T. gondii and anti-Neospora caninum IgG using indirect fluorescence antibody tests (IFATs), with titers ≥ 1:64 considered positive. Among the ewes, 45.1% tested positive for anti-T. gondii IgG in serum, with titers ranging from 1:64 to 1:16,384. The colostrum from 94.6% of the ewes also tested positive, although 74% had higher titers in their serum than in their colostrum. Concordance between serum and colostrum was high, with a kappa coefficient of 0.950. Lamb serum showed a perfect agreement with maternal colostrum (kappa = 0.962), demonstrating effective passive transfer of antibodies. This study confirms that colostrum is a reliable matrix for detecting anti-T. gondii antibodies and assessing passive immunity in lambs. The high concordance between serum, colostrum, and lamb titers suggests that IFATs on colostrum can be a practical tool for monitoring maternal antibody transfer, contributing to the better management of T. gondii infections in sheep flocks. Full article

RaTG13 is phylogenomically the closest related coronavirus to SARS-CoV-2; consequently, understanding the provenance of this high-value genome sequence is important in understanding the origin of SARS-CoV-2. While RaTG13 was described as being generated from a Rhinolophus affinis fecal swab obtained from a mine in Mojiang, Yunnan, numerous investigators have pointed out that this is inconsistent with the low proportion of bacterial reads in the sequencing dataset. Metagenomic analysis confirms that only 10.3% of small-subunit (SSU) rRNA sequences in the dataset are bacterial, which is inconsistent with a fecal sample. In addition, the bacterial taxa present in the sample are shown to be inconsistent with fecal material. The assembly of mitochondrial SSU rRNA sequences in the dataset produces a sequence 98.7% identical to R. affinis mitochondrial SSU rRNA, indicating that the sample was generated from R. affinis or a closely related species. In addition, 87.5% of the reads in the dataset map to the Rhinolophus ferrumequinum genome, and 62.2% of these map to protein-coding genes, indicating that the dataset represents a Rhinolophus sp. transcriptome rather than a fecal swab sample. Differential gene expression analysis reveals that the pattern of expressed genes in the RaTG13 dataset is similar to that of RaTG15, which was also collected from the Mojiang mine. GO enrichment analysis reveals the overexpression of spermatogenesis- and olfaction-related genes in both datasets. This observation is consistent with a mating plug found in female Rhinolophid bats and suggests that RaTG13 was mis-sampled from such a plug. A validated natural provenance of the RaTG13 dataset throws into relief the unusual features of the SARS-CoV-2 genome. Full article

Despite the impact of mastitis on sheep production worldwide, the pathogenesis and host response to bacterial infection of the ovine mammary gland are poorly characterized. Studies in cattle highlight the significance of the mammary epithelium in pathogen recognition and the subsequent host response. The objective of this study was to assess bacterial adherence, invasion, and Toll like receptor (TLR) gene expression in primary sheep mammary epithelial cells (pMEC) following co-culture with the three principal mastitis pathogens of sheep, Mannheimia haemolytica, Staphylococcus aureus, and Streptococcus uberis. S. aureus was 140-fold more adherent than S. uberis and 850-fold more adherent than M. haemolytica. However, only S. aureus was internalized after 3 h of co-culture. TLR1, 2, 3, 4, 6, and 9 were shown to be constitutively transcribed by pMEC. M. haemolytica induced upregulation of transcription of TLR1, 2, 3, and 4. By contrast, S. uberis and S. aureus induced concentration-dependent transcription of TLR2 and TLR4 with a higher level of transcription in cells stimulated with the bacteria at a multiplicity of infection (MOI) of 200 compared to cells stimulated with a MOI of 20. These experiments define the range of TLR genes constitutively transcribed in sheep pMEC and show that bacterial infection has the capacity to regulate transcription in a species-specific and concentration-dependent manner. Full article

Hospital-Associated Infections (HAIs) are caused by microorganisms that are not present before patients are admitted to healthcare facilities, and usually have multidrug resistance profiles. There is ample information and active research in human medicine to create preventive and control measures, but there have been fewer efforts in animal medicine, and studies in only a few countries have been examining how this problem presents in veterinary hospitals. In Mexico, there have been no studies on the presence of multidrug-resistant bacteria associated with HAIs in veterinary medicine. Therefore, the surfaces of inanimate objects and equipment in a university veterinary hospital for small species were sampled to search for bacteria with the potential to cause HAIs. After isolation, molecular identification and multidrug resistance tests were carried out. One bacterial strain was found to be resistant to carbapenems, third-generation cephalosporines, and penicillin/β-lactamase inhibitors. Additionally, other susceptible bacterial genera were identified as potential nosocomial pathogens in humans and animals. The presence of multidrug-resistant bacteria was confirmed. Further studies should be conducted to determine the isolate’s origin and its relationship with reported human clinical genotypes. This type of study highlights the importance of epidemiological surveillance and the need to not underestimate the potential risk posed by multidrug-resistant microorganisms. Full article

Butirosins are naturally occurring aminoglycoside (AG) antibiotics featuring a 4,5-disubstituted 2-deoxystreptamine (2-DOS) with a (2S)-4-amino-2-hydroxybutyrate (AHBA) side chain. This side chain has been shown to confer resistance against AG-modifying enzymes, leading to ongoing studies on the butirosin biosynthetic pathway and the corresponding enzymes. Butirosin is produced by Niallia (formerly Bacillus) circulans and Bacillus vitellinus, with most research focused on the first strain. To date, no whole-genome analysis has been performed on B. vitellinus. In this study, we sequenced the complete genome of B. vitellinus NBRC 13296 and performed a comparative analysis of different butirosin biosyntheric gene clusters (BGCs), including those from N. circulans. The complete genome of B. vitellinus NBRC 13296 comprises a 6,331,192-base circular chromosome with GC content of 52.68%. The annotation revealed the presence of 5605 CDSs, 70 tRNA genes, 30 rRNA genes, and 3 ncRNA genes in NBRC 13296. The highest dDDH and ANI values between NBRC 13296 and the most closely related type strain, Paenibacillus chitinolyticus KCCM 41,400, were 97.8% and 98.66%, respectively. Based on these genome-based comparative analyses, we propose reclassifying B. vitellinus NBRC 13296 as P. chitinolyticus. Genome mining revealed 18 gene clusters encoding the biosynthesis of diverse secondary metabolites in the genome of B. vitellinus NBRC 13296, indicating the enormous biosynthetic potential of this strain. The predicted structural diversity of the secondary metabolites includes aminoglycosides, PKS, NRPS, PKS–NRPS hybrids, metallophores, phosphonates, terpenes, β-lactones, and RiPP peptides. We then comparatively characterized the butirosin BGCs previously studied in several N. circulans strains. Additionally, the comparative genome analysis revealed complete butirosin BGCs identified from P. chitinolyticus KCCM 41,400, P. chitinolyticus NRRL B-23119, P. chitinolyticus NRRL B-23120, P. chitinolyticus B-14908, P. chitinolyticus YSY-3.1, P. chitinolyticus JMW06, Paenibacillus sp. GbtcB18, Paenibacillus sp. HGH0039, and Paenibacillus sp. MZ04-78.2. Finally, we identified the core region consisting of BtrS, BtrN, BtrM, BtrL, BtrA, BtrB, BtrC, BtrD, BtrD, BtrE, BtrF, BtrG, BtrH, BtrI, BtrI, BtrJ, BtrK, BtrO, BtrP, and BtrV, followed by an upstream region organizing BtrQ, BtrW, BtrX, BtrY, and BtrZ in the same transcriptional direction and sequential genetic arrangement, and a downstream region organizing various proteins based on BtrT, BtrR2, BtrU, and BtrR1. Our study provides insights into the reclassification of B. vitellinus NBRC 13296 to P. chitinolyticus and suggests the need for continued studies on butirosin biosynthesis from an enzymatic perspective. Full article

Carbon nanodots (CNDs) are nanoscale carbon-based materials with particle sizes typically less than 10 nm. They are characterized by their unique electronic, optical, and surface properties, as well as their bright and tunable fluorescence across the visible light spectrum. The process involved in synthesizing carbon nanodots is rather energy-consuming, expensive, and complicated. Motorcycle exhausts have been looked at as an environmental pollutant. In this paper, the bright side of motorcycle exhausts has been projected, whereby we have extracted carbon nanodots from motorcycle exhausts, using a simple and straightforward strategy. The nanomaterial was successfully isolated and characterized. The antimicrobial activity of the indigenously prepared nanomaterial was evaluated and coatings were prepared on glass and these nanocarbon coatings were demonstrated for their anti-biofilm activity. The results confirm the innovative and sustainable recovery of antibacterial carbon nanodots from environmental pollutants such as motorcycle exhaust. Full article

Coxiella burnetii (C. burnetii) can cause asymptomatic infections and acute, chronic, or localized manifestations affecting multiple organs. Doxycycline is the most effective treatment for Q fever. We report two cases of localized C. burnetii infections with no evident epidemiological link. Case reports: We present the case of a 51-year-old male patient admitted for low fever, dry cough, and malaise. The physical examination was unremarkable except for painful hepatomegaly. He was diagnosed with a liver abscess based on inflammatory markers, positive serology for C. burnetii, and abdominal computed tomography (CT) showing a large lesion (112/86/93 mm) within the right liver lobe. Blood cultures and the fluid obtained by percutaneous catheter drainage were negative. After 28 days of treatment with doxycycline, he was discharged well. At the three-month reevaluation, blood tests were normal, and a CT scan showed a minimal residual lesion. The second case was an 81-year-old female with many comorbidities, almost simultaneous acute ischemic stroke, and double-valve (native and prosthetic) infective endocarditis (IE). C. burnetii infection was confirmed by high titers of antibodies (phase I and II IgG), most probably the direct cause of both manifestations. These two cases presented with very rare manifestations of C. burnetii infections, highlighting its diagnostic difficulties. Conclusions: A clear distinction between acute and chronic Q fever is difficult in rare localized infections, as are organ abscesses. Coxiella burnetii may cause stroke and infective endocarditis, especially in the elderly. Even in the absence of epidemiological clues, in patients with localized infections, the C. burnetii etiology should be considered. Full article

The broad range of applications offered by synthetic biology and bioengineering has revolutionized the ability to design and redesign microorganisms to express specific functions, overcoming the limitations of natural biological systems. This advancement has been achieved through the use of mathematical models and genetic circuits, enabling the precise design of synthetic microbial communities. These are defined as artificially created communities through co-cultures of selected species that share similar characteristics and environments. Reprogramming an organism is carried out by inserting synthetic genetic circuits, which are designed in a controlled manner to obtain biotechnological products beneficial to humans, their health, and the environment. The potential applications in medicine, bioremediation, industry, and pharmaceuticals make the research of synthetic microbial communities a promising field for the future. However, the implementation of synthetic microbial communities carries potential risks, such as horizontal gene transfer and possible environmental impacts. It is crucial to carefully evaluate these functions and risks, considering biocontainment and the associated ethical and ecological implications. Full article

African Swine Fever (ASF) is a devastating viral hemorrhagic disease that causes high morbidity and mortality in domestic pigs and wild boars, severely impacting the swine industry. The etiologic agent, African Swine Fever virus (ASFV), mainly infects myeloid cells of the swine mononuclear phagocytic system (MPS). For other porcine viruses, in vitro culture models with primary cells are widely used as they mimic the in vivo viral replication behavior better compared to continuous cell lines. Our study validates this possible correlation for ASFV using cell culture models established for three different porcine macrophages, isolated from the lungs (porcine alveolar macrophages), blood (monocyte-derived macrophages) and spleen (spleen macrophages). The cells were infected with two genotype I and two genotype II strains with different pathogenic potential in vivo. The highly virulent strains replicated better in general than the low-virulent strains. This was most pronounced in monocyte-derived macrophages, although only statistically significant 18 h post-infection (hpi) in the intracellular genomic ASFV copies between E70 and the low-virulent strains. For this reason, we conclude that the different replication characteristics between the strains with different virulence do not proportionally represent the differences in pathology seen between the strains in vivo. Additionally, ASFV-positive cells were observed earlier in monocyte-derived macrophages (MDMs) compared to the alveolar and spleen macrophages, subsequently leading to an earlier rise in extracellular virus, and, ultimately, more MDMs were infected at the end of sampling. For these reasons, we propose MDMs as the best-suited cell type to study ASFV. Full article

Natural carotenoids (CARs) such as β-carotene, astaxanthin, lutein, norbixin, bixin, capsanthin, lycopene, β-Apo-8-carotenal, canthaxanthin, β-apo-8-carotenal-ester, and zeaxanthin are being explored for possible applications in feed, food, cosmeceuticals, and nutraceuticals. Three primary areas of carotenoid research are emerging: (1) encapsulations for improved chemical and physical properties; (2) natural source carotenoid manufacturing; and (3) preclinical, epidemiological, and clinical studies of carotenoids’ potential health benefits. The recent advancements in research on the chemistry and antioxidant activity, marketing strategies, dietary sources, bioavailability, and bioaccessibility, extraction, dietary consumption, encapsulating techniques, and health advantages of carotenoids are all extensively discussed in this review. Carotenoids are pigments found naturally in most fruits and vegetables, algae, plants, and photosynthetic bacteria. Carotenoids cannot be synthesized by humans and must be consumed in the form of food or supplements. There are several roles for carotenoids in human health. Although individual carotenoids may function in different ways, their main action is to act as antioxidants. There are validated techniques for separating and purifying carotenoids, yet, industrial production requires the development of economically viable techniques for larger-scale implementation. Carotenoids have been shown to boost cognitive performance and cardiovascular health, as well as help prevent some types of cancer. Despite evidence for carotenoids’ health benefits, major population-based supplementation trials have yielded conflicting outcomes for several carotenoids. This review includes recent developments in carotenoid metabolism and nutritional and health advantages. It also offers an outlook on future directions in these areas. Full article

Zinc oxide nanoparticles (ZnO NPs) have gathered interest because of their unique characteristics and potential applications. In the current work, ZnO NPs underwent an eco-friendly biosynthesis process using garlic peel extract. The biosynthesized ZnO NPs were characterized using different analyses including Ultraviolet-visible (UV-vis) spectroscopy, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), dynamic light scattering (DLS), and Fourier transform infrared spectroscopy (FTIR). The produced ZnO NPs exhibited a UV–vis spectrum absorption peak at 365 nm, thus indicating the formation of ZnO NPs. The SEM showed that the biosynthesized ZnO NPs had an irregular surface morphological shape with an average size of 17 nm, according to the DLS analysis. Based on the FTIR findings, the bioactive functional groups responsible for stabilizing and capping the ZnO-NPs were confirmed. The biosynthesized ZnO NPs exhibited 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging activity and antimicrobial activities against Gram-positive (Bacillus cereus) and Gram-negative bacteria (Klebsiella pneumonia). Therefore, the plant-mediated biosynthesized ZnNPs can be considered a promising candidate as an antioxidant and antimicrobial agent against pathogenic microbes found in different areas such as food safety and agriculture. Through the utilization of bioinformatics, we identified six potential targets for drug development in K. pneumonia and B. cereus, along with their corresponding interacting residues with zinc oxide nanoparticles. Additionally, our research revealed that the zinc oxide nanoparticles exhibited binding capabilities with the sulfiredoxin domain located at the specific targets of K. pneumonia, a crucial mechanism responsible for the repair of bacterial cells under oxidative stress. Full article

Leishmaniasis is a neglected disease with a global spread that affects both domestic and wild animals in addition to people. Leishmania donovani is the suspected anthroponotic cause of visceral leishmaniasis (VL) in India, where it is an endemic disease. The reservoir hosts play a crucial role in the life cycle of the Leishmania parasite. The complicated connection between the pathogen, vector, and reservoir exhibits geographical and temporal diversity. Human-to-human and, to a lesser extent, human-to-animal transmission are the principal mechanisms for the maintenance of anthroponotic diseases. A number of animals were examined for the presence of Leishmania parasites and the findings were reviewed in order to examine the role of animal reservoirs in domestic transmission of cutaneous leishmaniasis in endemic regions of India. The analysis objective was to assess the research conducted on domestic animals’ propensity to spread L. donovani in endemic areas, with a particular emphasis on how proximity and animal density may impact the prevalence of human leishmaniasis. Species of the L. donovani complex have distinct enzootic, zoonotic, and anthroponotic life cycles that depend on the environment. The majority of Leishmania spp. are zoonotic, spreading from non-human mammals to humans. Many nations have leishmaniasis as an endemic disease, and the Indian subcontinent (ISC) has an estimated two to three lakh people who are at risk. This systematic review evaluates the gaps in our understanding of disease transmission that contradict conventional wisdom about the reservoir(s) of visceral leishmaniasis and efforts to manage it on the Indian subcontinent. Fundamental concerns in VL epidemiology and ecology will be clarified by a better understanding of L. donovani infection in domestic animals and its transfer to sandflies. A deliberate, systematic search was conducted on PubMed, Science Direct, and Google Scholar using keywords such as “Leishmania donovani”, “zoonotic visceral leishmaniasis”, and “wild animal reservoir for Leishmania donovani”. A total of 530 potentially relevant references were obtained from these databases, and 507 were not considered due to copy avoidance, irrelevant titles, research publications from nations other than India, or modified compositions. Among the remaining 23 investigations, 20 were rejected, and only 3 were included in the present study. Finally, three research papers with 867 goats, 161 cattle, 106 chickens, 26 sheep, three buffaloes, 406 dogs, and 309 rats were reported. Along with these data, studies across Asian and African countries that are considered VL-endemic areas have been discussed. According to the review, goats are the epidemic’s primary host and possible reservoir in several regions of India. In the endemic regions of the disease, some species of rodents, along with the canines, appear to be maintaining the L. donovani transmission cycle. Full article

Klebsiella (K.) pneumoniae is a major pathogen in human and veterinary medicine, known for its high resistance rates. Comprehensive resistance data are essential to combat global antibiotic resistance. This study aims to (a) document the prevalence of resistant K. pneumoniae and (b) assess the utility of routine laboratory data for passive monitoring. We analyzed a dataset of 175,171 samples from diseased dogs and cats in Germany collected between 2019 and 2021, identifying 1185 K. pneumoniae isolates with measurable minimum inhibitory concentration values. We evaluated resistance rates to a third-generation cephalosporin (cefovecin) (16.3%), chloramphenicol (16.1%), doxycycline (13.9%), enrofloxacin (8.9%), gentamicin (6.0%), nitrofurantoin (24.8%), and sulfamethoxazole-trimethoprim (15.0%). Notably, feline K. pneumoniae isolates from the urinary tract showed a high cefovecin resistance rate of 70.0%. Comparing our findings with third-generation cephalosporin-resistant human isolates from the Antimicrobial Resistance Surveillance database (ARS) maintained by the Robert Koch Institute revealed a lower resistance rate (7.7%). This study presents Germany’s most comprehensive dataset on K. pneumoniae resistance in companion animals over a three-year period. These findings can strengthen national resistance monitoring efforts and enhance data interpretation through substantial datasets. Full article

Antibiotic resistance is a global health problem. The human gut microbiome is implicated in the dynamics of antibiotic resistance acquisition and transmission, with the gut microbiota thought to play a crucial role. This study aimed to determine the potential influence of the human gut bacteria microbiota on the gut resistome and the relationship between the gut microbiota and Escherichia coli resistome. The PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guideline was used to systematically review studies that characterized the gut microbiota and resistome using metagenomic analysis and/or those that reported gut E. coli resistome in healthy individuals. Changes in the diversity and abundance of the bacterial gut microbiota and the resistome across different time points and participant groups were summarized. Additionally, using E. coli resistome as a proxy for the gut resistome, the microbiota composition of the gut harboring antibiotic-resistant E. coli was examined. The findings suggest that lower bacterial microbiota diversity is likely associated with an increased abundance of the overall gut resistome. Age-related differences were observed, with younger infants exhibiting lower microbiota diversity and higher antibiotic resistance gene (ARG) abundance compared to older infants and adults. Studies that reported positive correlations between the relative abundance of Proteobacteria and ARGs were mainly driven by members within the Enterobacteriaceae family, mainly E. coli. This study also reveals that human gut microbiome studies investigating the gut resistome using metagenomic sequencing approaches in healthy individuals are uncommon. Full article

Chronic obstructive pulmonary disease (COPD) is a respiratory and systemic disease affecting more than 300 million people globally every year, and it also becomes a substantial economic burden. COPD is commonly comorbid with various underlying diseases such as cancer, cardiovascular diseases, cerebrovascular diseases, diabetes mellitus, osteoporosis, etc. It has been shown that statins can improve a significant decline in pulmonary function among COPD patients due to their pleiomorphic effect. Some systematic reviews also reported that statins reduced the risk of COPD-related events such as cancer and cardiovascular events, eventually resulting in more favorable outcomes than for non-statin user COPD patients. However, the physiological mechanism is still elucidated. Recently, it has been reported that statins influence the gut microbial composition with increased relative abundance of Akkermansia muciniphila and Faecalibacterium prausnitzii and act with pleiomorphic effects such as anti-inflammatory and anti-cancer effects through modulating gut dysbiosis. We described this review to focus on whether statins can be a useful preventive option for COPD. Full article

The severity of adenovirus infection or the success of adenovirus-vectorized gene therapy largely depends on the efficiency of viral entry into cells. Various drugs can alter viral entry. This study evaluated the effects of dexamethasone, paracetamol, diclofenac, ibuprofen, and ketorolac on adenovirus entry into cells in vitro and in vivo. SiHa cell cultures pretreated with dexamethasone, paracetamol, diclofenac, ibuprofen, ketorolac, or no drug were exposed to the Ad-BGal vector. The percentage of cells showing vector entry was quantified microscopically. In vivo, BALB-C mice pretreated for 7 days with the drugs or no drug were exposed to the Ad-BGal vector intravenously (IV) or via oral (VO). Organs showing vector entry were identified by X-Gal staining and eosin counterstaining. Hepatic areas with adenovirus entry were quantified in µm². Dexamethasone, paracetamol, and ibuprofen increased adenovirus entry both in vitro and in vivo. Diclofenac increased entry only in vitro. Ketorolac did not affect adenoviral entry. The liver exhibited the most significant changes, with dexamethasone, paracetamol, and ibuprofen increasing adenovirus entry the most. Oral administration of the vector showed that dexamethasone increased its entry into the pharynx. Some physicochemical properties of the drugs (MW (g/mol), LogP, MR [cm³/mol], tPSA, CMR, LogS, and ClogP) were analyzed, and their possible implications on cell membrane properties that could potentially influence adenovirus entry through mechanisms independent of cellular receptors were discussed. Anti-inflammatory drugs could alter adenoviral infections and adenovirus vector-based gene therapies, necessitating further research. Full article

Lactobacilli are considered important probiotics for the prevention of some infections. In this study, the antifungal effect of both cells and cell-free supernatants of twenty-three strains of lactobacilli were investigated against Candida albicans by co-aggregation, agar diffusion assay, agar spot assay and co-culture assay. In all cases, a fungistatic effect was recorded. In the agar diffusion assay and agar spot assay, an effect was established primarily for heterofermentative species via the production of lactic acid. The anti-Candida effect was higher with microbial suspension than with cultural supernatants in the co-culture assay. A strain-specific reduction in the yeast growth up to 28.9% in MRS broth and up to 17.1% in BHI broth was observed. Cells of Limosilactobacillus fermentum LLF-01 and Limosilactobacillus reuteri LLR-K67 showed the highest activity in both model systems. For all strains, a lower reduction up to 9.7% was recorded with cultural supernatants. L. fermentum LLF-01 showed the highest ability of co-aggregation (64.8%) with C. albicans, followed by Lactobacillus acidophilus LLA-01, Lactobacillus gasseri LLG-V74, Lactobacillus delbrueckii subsp. bulgaricus LLB-02 and two strains of Lactobacillus delbrueckii subsp. lactis LLL-14 and LLL-F18. The present study showed the potential of several strains of lactobacilli to affect the population of C. albicans in vitro. The combination of cultures with proved anti-Candida and co-aggregation activity in a probiotic formula may have a positive effect for the prevention of yeast overgrowth in the gut and hence for the suppression of candidiasis. Full article

This article presents a comprehensive overview of recent discoveries and advancements in the field of steroid chemistry, highlighting the isolation and characterization of various steroidal compounds from natural sources. This paper discusses a wide range of steroids, including pregnane steroids, steroidal alkaloids, ketosteroids, and novel triterpenoids, derived from marine organisms, fungi, and plants. Significant findings include the isolation of bioactive compounds such as the cytotoxic erectsterates from microorganisms, soft corals, the unusual tetracyclic steroid penicillitone from a fungal culture, and innovative steroidal derivatives with potential anti-inflammatory and anticancer activities. The synthesis of steroids from microorganisms as a tool for pharmaceutical development is also explored, showcasing the role of microbial biotransformation in generating steroidal drugs. Additionally, this paper emphasizes the ecological and medicinal relevance of these compounds, which are often used in traditional medicine and have potential therapeutic applications in treating diseases like cancer and microbial infections. This article serves as a vital resource for researchers interested in the chemical diversity of steroids and their applications in drug discovery and development. Full article

Cucumis sativus L. plants are subjected to stress during production, affecting their growth, development, and fruit quality due to abiotic factors. Thus, the aim of this research is to evaluate Pseudomonas paralactis, Sinorhizobium meliloti, and Acinetobacter radioresistens plant growth promoting rhizobacteria (PGPR) effect on C. sativus plants under three substrate moisture levels (100, 75, and 50%). A randomized complete block design (RCBD) was used with an A x B arrangement: (1) factor A (inoculant) with four levels; (2) PGPR and control (without bacterium); (3) factor B (substrate moisture content) with three levels. Plant height, root length, and fresh weight increased by inoculating PGPR (121%, 135%, and 134%, respectively); likewise, these variables increased with higher moisture content (177%, 204%, and 234%, respectively), while the effect of the interactions of the PGPR and the moisture content in the substrate showed statistical differences in plant height increasing of 197% and root length of 267%. On the other hand, the content of phenols, flavonoids, and antioxidant capacity was statistically different (p ≤ 0.05) in inoculated plants, with PGPR increasing by 117%, 126%, and 150% respectively. In the moisture content of the substrate, statistical differences were observed, with an increase in the flavonoid content (114%) and antioxidant capacity (116%). The assimilation of nitrogen was higher by 274% and phosphorus by 124% with the PGPR inoculation, the moisture content increased the nitrogen content in the plant (257%) and the phosphorus content in plant (135%), showing significant differences (p ≤ 0.05). However, the interaction of PGPR and moisture content only presented statistical differences in nitrogen assimilation. PGPR can be considered as an alternative to obtain vigorous cucumber seedlings. Full article

Tuber aestivum, commonly known as the summer truffle, is typically found in various parts of Europe where it grows naturally. However, its presence in Portugal was not confirmed until now. The first fruit bodies were collected in April 2024 at stone pine stands (Alenquer and Arruda dos Vinhos, Lisbon) and in June at holm oak stands (Salir, Faro). These specimens are characterized by hypogeous, subglobose, black ascomata with a peridium surface covered with pyramidal warts. Ascopores are subglobose-to-broadly ellipsoid, distinctively ornamented, usually 1–6 per asci. According to the results of the internal transcribed spacer (ITS) rDNA sequence analysis, these specimens form a well-supported group within the Aestivum clade, with T. aestivum being the closest phylogenetic taxon. This remarkable discovery opens up new opportunities for truffle exploitation in Portugal thanks to the summer truffle’s gastronomical value and high market prices. Full article

Recently, studies suggest that the protective effects of Lactobacillus within the female reproductive tract may be partly due to their ability to form biofilms. This study aims to explore the possibility that Lactobacillus can produce key mediators to further bolster the survival of biofilms in human vaginal microbiomes. Three bacterial species, namely, Lactobacillus gasseri, L. crispatus, and L. jensenii, sourced from human female subjects were used to carry out experiments examining the growth of biofilms using a microfermenter system. The bacteria were used to inoculate a glass rod spatula which was subsequently transferred to the microfermenter system. The resulting biofilm growing on the glass spatula was harvested in media and stored in a −80 °C freezer for gas chromatography–mass spectroscopy analysis. We found that quorum sensing compounds, acyl homoserine lactones (AHLs), were detected in the biofilm of L. crispatus and L. jensenii, but none were detected in L. gasseri. The biofilm produced by L. crispatus and L. jensenii was much higher in quantity than the biofilm produced by L. gasseri. Aside from oligopeptides quorum sensing, lactobacilli were found to also have AHL compounds that may help them produce more biofilms and improve the survival and growth of their bacterial communities in the female genital area. Full article

Increasing evidence suggests that the gut microbiota, through the “microbiota–gut–brain axis”, can regulate anxiety, mood, and cognitive abilities such as memory and learning processes. Consistently with this, treatments altering the gut microbiota, such as antibiotics and probiotics, may influence brain function and impact behavior. The mechanisms that underlie the interplay between the intestinal microbiota and the brain have been intensively studied. We aimed to investigate the effects of two probiotic lactobacilli strains, Lacticaseibacillus rhamnosus 12L and Lactiplantibacillus plantarum 8PA3, on behavioral disorders in mice induced by a two-week parenteral treatment with broad-spectrum antibiotics. On completion of the treatment, the mice were subjected to behavioral tests, including the open field test (OFT), novel object recognition test (ORT), and T-maze test. Antibiotic-treated mice demonstrated anxiety-related behavior, decreased cognition, and retarded exploratory activity that were ameliorated by the administration of probiotics. As was determined by high-performance liquid chromatography (HPLC), both tested strains produced serotonin and its metabolite 5-hydroxyindoleacetic acid (5-HIAA), as well as dopamine, which was further metabolized into norepinephrine by L. plantarum 8PA3 and epinephrine by L. rhamnosus 12L. Moreover, these lactobacilli were found to harbor catecholamines and 3,4-dihydroxyphenylacetic acid (DOPAC) in their biomass when grown on MRS broth. Additionally, L. plantarum 8PA3 and L. rhamnosus 12L were able to impact oxidative stress via H₂O₂ production and antioxidant activity, as determined in this study by the ferrous oxidation–xylenol orange (FOX) assay and the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay, respectively. The results obtained in this study support the role of probiotics as a promising therapeutic for neurological disorders. However, more investigations are required to confirm the clinical significance of this finding. Full article