Failures in endodontic treatments are common due to microbial resistance in the pulp canal. The study evaluated the in vitro activity of polyhexamethylene guanidine hydrochloride (PHMGH) against endodontic strains, as well as in vivo toxicity. Using minimum inhibitory concentration and minimum bactericidal concentration techniques, PHMGH was effective against all microorganisms, even at low concentrations. At 50.0 µg/mL, it inhibited Enterococcus faecalis; furthermore, when compared to chlorhexidine (CLX), it demonstrated values 19 times lower against Candida albicans. The polymer's activity was also determined by agar diffusion, evaluating products A (calcium hydroxide - Ca(OH)2, as a reference), B (Ca(OH)2 combined with physiological solution, reference with a vehicle), C (PHMGH 6.25%), D (PHMGH 3.125%), E (PHMGH 1.5625%), F (PHMGH 0.78125%), G (PHMGH 6.25% and Ca(OH)2), H (PHMGH 3.125% and Ca(OH)2), I (PHMGH 1.5625% and Ca(OH)2), J (PHMGH 0.78125% and Ca(OH)2), and K (positive control, CLX 0.12%). Products containing PHMGH were more effective than the references against all strains, and C, D, and G were more effective than CLX against Peptostreptococcus anaerobius, Actinomyces naeslundii, and Actinomyces viscosus. According to the fractional inhibitory concentration index, the combination of PHMGH and CLX showed indifference for Peptostreptococcus anaerobius, Actinomyces naeslundii, Actinomyces viscosus and Escherichia coli, antagonism for Candida albicans, and synergy for Enterococcus faecalis. The toxicity of PHMGH at different concentrations was tested in Caenorhabditis elegans and did not show lethality in nematodes, with the LC50 observed only at the highest concentration (100 µg/mL) after two days of exposure. It is suggested that PHMGH exhibited antimicrobial activity against endodontic strains and low toxicity, raising expectations for new preventive and therapeutic products in endodontics.

Despite meticulous precautions, contamination of genomic DNA samples is not uncommon, which can significantly compromise the analysis of microorganisms' whole-genome sequencing data, thus affecting all subsequent analyses. Thanks to advancements in software and bioinformatics techniques, it is now possible to address this issue and prevent the loss of the entire dataset obtained in a contaminated whole-genome sequencing, where the DNA of another bacterium is present. In this study, it was observed that the sequencing reads from Streptomyces sp. BRB040, generated using the HiSeq System platform (Illumina Inc., San Diego, USA), were contaminated with the DNA of Bacillus licheniformis. To eliminate the contamination in Streptomyces sp. BRB040, a combination of tools available on the Galaxy platform and other web-based resources were used (MeDuSa and Blast). The contaminated reads were treated as a metagenome to isolate the genome of the contaminating organism. They were assembled using the metaSPAdes, resulting in a large scaffold of 4.187 Mb, which was identified as Bacillus licheniformis. After the identification of the contaminating organism, its genome was used as a filter to remove sequencing reads that could align using then Bowtie 2 software for this step. Once the contaminated reads were removed a new assembly was performed using the Unicycler software, yielding 117 contigs with a total size of 7.9 Mb. The completeness of this genome was assessed through BUSCO, resulting in a completeness of 95.9%. We also used an alternative tool (BBduk) to eliminate contaminated reads and the resulting assembly by Unicycler generated 85 contigs with a total size of 8.3 Mb and completeness of 99.5%. These results were better than the assembly obtained via SPAdes, which generated less complete genomes (maximum of 97.8% completeness) compared to Unicycler and which was unable to perform an adequate assembly of the data obtained from decontamination by BBduk. When compared with the uncontaminated BRB040 genome, which has a total size of 8.2 Mb and completeness of 99.8%, this pipeline revealed that the assembly performed with the decontaminated reads via BBduk presented better results, with completeness 0.3% lower than the reference. The genome mining of both genomes using antiSMASH 7.0 revealed the number of 24 Biosynthetic Gene Clusters (BGCs) for BBduk data as well as in the control assembly of the BRB040. In silico decontamination process allows the genome mining of BGCs despite the loss of nucleotides. These findings show that contamination can be effectively removed from a genome using readily available online tools, while preserving a dataset suitable for extracting valuable insights into the secondary metabolism of the target organism. This approach is particularly beneficial in scenarios where resequencing samples is not immediately feasible.

Developing an effective vaccine for haemorrhagic septicaemia (HS) in cattle and buffaloes is urgently needed. While preferred for their safety, achieving sufficient, cross-protective, and long-lasting immunity is still challenging when administering inactivated vaccines. This study aimed to assess the efficacy of four inactivating components comprising three inactivating agents: (1) Binary ethylenimine (BEI), (2) Formalin, (3) a combination of BEI and Formalin, and (4) Hydrogen peroxide (HO), in inactivating Pasteurella multocida to enhance HS vaccine potency. HO demonstrated the fastest inactivation kinetics, killing Pasteurella multocida within a few minutes. The combination of BEI and Formalin showed relatively rapid inactivation compared to Formalin or BEI alone. BEI, known for targeting nucleic acids with minimal impact on protein integrity, showed promise but required higher concentrations (8 mM) and a longer duration (16 h) for complete inactivation. Based on the inactivation kinetics, 8 mM BEI, 0.1% Formalin, 8 mM BEI + 0.1% Formalin, and 1% HO were chosen for the experimental vaccine formulations. The inactivated Pasteurella multocida were adjuvanted with Montanide ISA-201 oil adjuvant and evaluated in mice model. All vaccine formulations elicited protective responses of over 6.5 log units, indicating the high potency of the vaccine formulations. Notably, the vaccine prepared with an HO inactivating agent elicited protection of > 8 log units. Our study concludes that HO, with its rapid inactivation kinetics and safety profile, presents a promising alternative inactivating agent for HS vaccine development. Future studies should evaluate the protective efficacy of HO-inactivated vaccines in target animals.

Fusarium keratitis (FK) is an important clinical condition that can lead to blindness and eye loss, and is most commonly caused by the Fusarium solani species complex (FSSC). This study evaluated the susceptibility of planktonic cells and biofilms of FSSC (n = 7) and non-FSSC (n = 7) isolates obtained from patients with keratitis from a semi-arid tropical region to amphotericin B (AMB), natamycin (NAT), voriconazole (VRZ), efinaconazole (EFZ), and luliconazole (LCZ). Analysis of clinical data showed that trauma was the most common risk factor for FK patients. Disease onset was longer in non-FSSC group (3-30 days) than in the FSSC group (3-7 days). FSSC strains were less susceptible to AMB and VRZ than non-FSSC strains (p < 0.05). Susceptibility to NAT, LCZ and EFZ was similar between isolates of FSSC and non-FSSC groups. Overall, patients infected with non-FSSC showed a better response to antifungal treatment. Corneal transplantation was more common in patients infected with FSSC (3/7) than in those infected with non-FSSC (1/7). Mature biofilms showed a poor response to antifungal treatment. Patients infected with Fusarium strains capable of forming antifungal tolerant biofilms had more complex therapeutic management, requiring two antifungals and/or corneal transplantation (p < 0.05). This study highlights the importance of mycological diagnosis and the antifungal susceptibility testing in the clinical management of FK. The ability of Fusarium to form antifungal tolerant biofilms poses a challenge to clinicians and urges the development of new antibiofilm therapeutics.

Vulvovaginal candidiasis (VVC) represents the second cause of vaginal infections in childbearing-age women. It mainly affects the vulva and vagina; however, other organs can be compromised, with consequences that are not well known yet. To evaluate the ability of Candida albicans, inoculated into the vaginal lumen of mice, to migrate to the uterus and ovaries. Female Balb/c mice, 6 weeks old, were estrogenized and infected intravaginally with 1 × 10 CFU/ml of C. albicans for the dual objectives of histopathological evaluation and fungal burden quantification in the vaginal, uterus, and ovary tissues, on days 1, 3, and 5 post-infection. Estrogenized and infected mice presented vaginal exudate and an edematous and erythematous uterus. Vaginal histopathological analysis showed intense desquamation, keratinization, fungal structures, and an inflammatory reaction one day after infection. In the uterus, an inflammatory response and a few fungi from the third day onwards were observed. Similarly, the ovary showed the same changes, but at a lower intensity. A high fungal burden was detected in the vaginal tissue from the first day, reaching nearly 6 log CFU/g on the fifth day. C. albicans inoculated into the vaginal lumen of estrogenized mice was able to invade the vaginal tissue one-day post-infection and was detected in the uterus and ovaries within three days.

Plant-associated microbiome plays important role in maintaining overall health of the host plant. Xanthium strumarium displaying resilience to various environmental fluctuations may harbor some bacterial isolates which can help this plant to grow worldwide. The present study aims to isolate endophytic and rhizospheric bacteria from X. strumarium and assess their plant growth-promoting and Ralstonia solanacearum antagonism activity. From a total of 148 isolated bacteria, 7 endophytic and 2 rhizospheric bacterial isolates were found to endow with significant in vitro plant growth promotion activities. The 16S rRNA gene sequence similarity of the 7 endophytic isolates has revealed these bacteria belonging to 5 genera viz. Curtobacterium, Pantoea, Pseudomonas, Microbacterium and Paracoccus whereas, the two rhizospheric isolates were identified as species of Ralstonia pickettii and Priestia megaterium. Maximum growth promotion was observed using the strains Pseudomonas fluorescens XSS6 and Microbacterium hydrothermale XSS20 in the assay conducted on tomato plants. In the in planta inhibition assay of R. solanacearum carried out in tomato seedlings using root bacterization method, Pseudomonas fluorescens XSS6 and Panotea vagans XSS3 showed antagonistic activity with biocontrol efficacy of 94.83% and 83.96%, respectively. GC-MS analysis detected several known antimicrobial compounds in the extract of the culture supernatant of Pseudomonas fluorescens XSS6 and Panotea vagans XSS3 strains, which may contribute to the inhibition of R. solanacearum by these strains. The results of our study indicated that the bacteria associated with X. strumarium exhibit multiple plant-beneficial effects. These bacteria have the potential to be developed as effective biofertilizers and biological control agents, promoting sustainable agriculture practices.

The influence of arbuscular mycorrhizal fungi (AMF) inoculation on the growth and physiology of Phaseolus vulgaris L. and Zea mays L. in the Brazilian tropical seasonal dry forest is not well known. We examined the effects of indigenous AMF species inoculation on these two annual crops at phosphorus-deficient soils under glasshouse conditions. The AMF species used as inoculum were collected from the root zone of Mimosa tenuiflora, a native plant of the Caatinga ecoregion. The inoculum was propagated in plastic pots with Trifolium sp. as the host plant. We investigated the effect of four treatments: (1) Control- non-inoculated; (2) Acaulospora inoculum- inoculation with A. tuberculata; (3) Gigaspora inoculum- inoculation with G. gigantea; and (4) Mixed inoculum- inoculation with both Acaulospora and Gigaspora species. We found that inoculation with the indigenous AMF community enhanced plant dry biomass, plant P concentration, root colonization, and physiological responses for both model plants. This study highlighted the importance of exploring the P molecule as an integral element in plant development and presents the AMF inoculation as an efficient alternative to overcome low-P conditions, leading to improved nutrient acquisition in low-fertility soils, better growth conditions through enhanced physiological responses, and ultimately increased plant dry biomass.

The intestinal microbiota is widely recognized as an integral factor in host health, metabolism, and immunity. In this study, the impact of dietary fiber sources on the intestinal microbiota and the production of short-chain fatty acids (SCFAs) was evaluated in Lohmann White laying hens. The hens were divided into four treatment groups: a control diet without fiber, a diet with wheat bran (mixed fibers), a diet with insoluble fiber (cellulose), and a diet with soluble fiber (pectin), with six replicates of four hens each. Cecal content from 24 hens was analyzed using 16 S rRNA sequencing, while SCFA concentrations were measured in blood serum. Alpha diversity analysis revealed significant variations in microbial richness and diversity among treatments, with higher species richness observed in hens fed wheat bran and cellulose, as indicated by Shannon indices. Principal Coordinates Analysis (PCoA) showed significant differences in microbial composition between the control group and the fiber-supplemented groups. The predominant phyla were Bacteroidetes, Campilobacterota, Firmicutes, and Spirochaetota, with a notable increase in Bacteroidetes in fiber-supplemented groups. Regarding SCFAs, fiber inclusion increased acetic and propionic acid concentrations compared to the control group. Diets with mixed fibers (wheat bran) resulted in the highest acetic acid levels, while propionic acid was most abundant in hens fed soluble fiber (pectin). These findings demonstrate that dietary fiber inclusion to laying hens enhances microbial diversity, stimulates SCFA production, and contributes to host metabolism and health.

Adjuvants are crucial for maintaining specific, protective, and long-lasting immunity. Here, we aimed to evaluate the antigenic and immunogenic activity of a recombinant form of the S1 domain of the Spike protein, associated with biogenic silver nanoparticles (bio-AgNP) and Alhydrogel as an alternative and conventional adjuvant, respectively, for a SARS-CoV-2 subunit vaccine. We produced and evaluated the antigenicity of the recombinant S1 (rS1) protein by testing its recognition by antibodies present in SARS-CoV-2 positive human serum. The immunogenicity of the rS1 protein was assessed in vivo by its ability to induce antibody production in mice. Furthermore, we sought to establish the types of humoral and cellular immune responses generated through intramuscular immunization in BALB/c mice with the rS1 + bio-AgNP vaccine. The recombinant S1 (rS1) protein was successfully cloned, expressed in Escherichia coli, and confirmed to have strong antigenic potential, being recognized by human antibodies up to a 1:51,200 serum dilution. In vivo assays showed that vaccines using rS1 with either bio-AgNP or Alhydrogel as adjuvants induced high and consistent antibody titers (1:51,200) and a range of antibody isotypes in mice. Cellular immune response analysis revealed significant IL-10 expression with rS1 + bio-AgNP and both IL-10 and TNFα expression with rS1 + Alhydrogel. These results support rS1 + bio-AgNP as a promising vaccine candidate for future development, highlighting its potential not only as a viable alternative to traditional adjuvants but also as an innovative contribution to advancing more effective and accessible immunological strategies.

Endophytic actinomycetes are potential sources of novel pharmaceutically active metabolites, significantly advancing natural product research. In the present investigation, secondary metabolites from two endophytic actinomycetes, Streptomyces parvulus GloL3, and Streptomyces lienomycini SK5, isolated from medicinal plant taxa, Globba marantina, and Selaginella kraussiana, exhibited broad-spectrum bioactivity. Ethyl Acetate (EA) extract of SK5 showed antimicrobial activity against nine human pathogens, including Methicillin-resistant Staphylococcus aureus (MRSA), Candida tropicalis, and C. albicans, with a minimum microbicidal concentration (MMC) of 50-300 µg mL. It healed the MRSA-mediated wounds in Swiss albino mice in vivo. EA extracts dissociate the pathogenic cell membranes and cause leakage of biomacromolecules-nucleic acid, protein, and potassium ions. Also, critical housekeeping enzymes involved in the cellular respiratory mechanisms of the pathogens were blocked. GloL3 has antioxidative potentialities against DPPH, ABTS, FRAP, and HO free radical generators with an IC value of 21.18 ± 0.33, 43.58 ± 0.91, 88.24 ± 1.24, and 111.03 ± 6.42 µg mL. It improves the enzymatic antioxidant parameters in treated peritoneal macrophage cells of Swiss albino mice. Constituents of the EA extracts of GloL3 and SK5 are bactobolin, actinobolin, 5-(2-aminoethyl)-1 H imidazole-2-carbaldehyde, isovaleric acid, fulvic acid, phenol, 4-[2-(methylamino) ethyl]-, eicosanoic acid, heptadecanoic acid, etc. The present findings suggest that metabolites from the endophytes of medicinal plants hold potent pharmaceutical utilities.

The objective of this work was to investigate the biofilm production capacity of the isolate EB-40 (Bacillus cereus) in a culture medium for the multiplication of microorganisms and in roots of in vitro grown banana explants. It was observed that the isolate was able to produce biofilms in tryptone, soy and agar (TSA) culture medium and in the roots of explants. The format, architecture and location of the biofilms in TSA culture medium presented an exopolymer matrix formed by EB-40 presented coccoid bacillary cells and fibrillar structures. In roots explants was verified the formation of microcolonies adhered to the root hairs. The information obtained in this experiment allowed inferring the ability of the isolate to produce biofilms and the colonization pattern shown when associated with banana tree roots.

Plant parts such as roots, bark, leaves, flowers, and fruits that hold ethnopharmacological significance are naturally prone to microbial contamination, influenced by environmental factors like moisture and humidity. This study focuses on assessing the microbial load in the raw material of Tribulus terrestris (TT). The primary bacterium isolated from the pulverized raw material was identified as Bacillus haynesii through 16S rRNA sequencing. Biochemical assays revealed the organism's ability to utilize lysine and ornithine, produce urease, and generate hydrogen sulfide. The bacterium exhibited resistance to multiple antibiotics and caused 21.5% hemolysis in RBC lysis assays. To reduce microbial contamination, Glutaraldehyde (GA) and polyhexamethylene biguanide (PHMB) were tested, with GA at 1% reducing the microbial load by 99% without affecting the yield (0.5%) or bioactive saponin content. High-Performance Liquid Chromatography (HPLC) confirmed the absence of residual GA, ensuring an eco-friendly and safe process. This highlights the importance of quality control measures, including Hazard Analysis and Critical Control Points (HACCP) regulations, in maintaining the integrity of herbal extracts.

Proteases are hydrolases that act on peptide bonds, releasing amino acids and/or oligopeptides, and are involved in essential functions in all organisms. They represent an important segment of the global enzyme market, with applications in the food, leather, detergent, and pharmaceutical industries. Depending on their industrial use, proteases should exhibit high activity under extreme conditions, such as low temperatures, e.g. cold-active protease may have potential uses in the detergent industry. Cold-active enzymes show high catalytic constants (k) at low temperatures and thermolability, allowing their inactivation at moderate temperatures. This work aimed to characterize an extracellular proteolytic extract produced by an Antarctic isolate identified as Flavobacterium sp. strain AU13, and to evaluate its biotechnological potential as a detergent additive. By mass spectrometry analysis, we identified a major 50 kDa protease, with high identity with an epralysin from Pseudomonas fluorescens Pf0-1, an alkaline extracellular metalloprotease belonging to the serralysin subfamily. The AU13 proteolytic extract showed metalloprotease activity and, maximal activity over a wide pH range (pH 5 to 8); it also showed maximal activity at 40 °C, suggesting that this extracellular protease is a cold-active enzyme. The AU13 proteolytic extract demonstrated stable and compatible activity with surfactants and oxidants, making it a promising additive for commercial laundry detergents. Its ability to function effectively in cold-water washing conditions offers a significant advantage over conventional enzymes, potentially improving energy efficiency in industrial processes. The biochemical properties and performance of the AU13 proteolytic extract in the presence of laundry detergents, suggest that AU13 produces an extracellular protease with a biotechnological potential.

Carbon dots in biosensing have advanced significantly, adding improvements to different detection techniques. In this study, an amperometric immunosensor for Salmonella Thyphimurium was designed using antibodies labeled with carbon dots (Cdots) from pequi almond (Caryocar brasiliensis). Cdots were synthesized by pyrolysis and characterized by FTIR, UV/fluorescence, electrochemistry, zeta potential, and transmission electron microscopy (TEM). A particle size of 6.80 ± 2.13 nm was estimated, and the zeta potential was - 47.4 mV, indicating the preponderant presence of acidic groups, as confirmed by FTIR. The impedance evaluation of the response of biosensors assembled for live (Rct = 13.4 kΩ) and dead (Rct = 499.7 Ω) Salmonella showed a significant difference in their values, in agreement with chronoamperometric analyses, which had their current values drastically reduced from - 2.2 mA (live) to 0 mA (dead). An analytical curve for Salmonella was established with the limit of detection lower than 1 CFU/mL. This electrochemical biosensor using pequi carbon dots for antibody labeling showed promising results for detecting the pathogen. Thus, carbon dots can be used as substitutes for enzymes in labeling antibodies used in the design and production of sensors.

Diabetes is a critical worldwide health problem. Numerous studies have focused on producing recombinant human insulin to address this issue. In this research, the process factors of production of recombinant His-tagged proinsulin in E. coli BL21 (DE3) strain were studied. Bacterial culture factors with significant effects on the amount of produced recombinant proinsulin were screened using a Taguchi L8 orthogonal array. Proinsulin expression was conducted under predicted optimal conditions. The folded impure His-tagged proinsulin was purified using immobilized metal ion affinity chromatography (IMAC). A novel IMAC sequence order combined with the use of non-His-tagged C-peptide cleavage enzymes followed by His- tagged enterokinase enzyme enabled simultaneous protein purification and elimination of C-peptide and His-tag in just one step. Statistical analysis revealed that the amount of produced proinsulin was significantly affected by several factors including the post-induction incubation temperature, Isopropyl ß-D-1-thiogalactopyranoside (IPTG) concentration, pre-induction incubation temperature, the glucose concentration, bacterial cell population at induction step, and the time of harvesting. The optimized model resulted in an empirical maximum proinsulin concentration of 254.5 ± 11.7 µg/ml. The high purity of the purified insulin (> 96% by SDS-PAGE) indicated that applied IMAC sequence order could be considered an efficient technique for on-column cleavage and insulin purification.

Aeromonas inhabit diverse aquatic habitats and are recognized as both opportunistic and primary pathogens of fish and humans. This study delineates the biochemical and gyrB sequence-based molecular identification of 14 Aeromonas strains isolated from aquatic environments in Kerala, India, identifying them as A. dhakensis (50%), A. hydrophila (28.6%), and A. jandaei (21.4%). These strains exhibit a high prevalence of virulence genes (act, flaA, ser, gcat, lip, and ela) implicated in pathogenesis in both fish and humans. These findings underline the emergence of A. dhakensis, often misidentified as A. hydrophila, as a potential pathogen, highlighting the necessity for comprehensive identification methods. Significantly, all strains demonstrated beta-hemolysis and moderate to strong biofilm formation, enhancing their infectivity potential. Moreover, all isolates exhibited multidrug resistance, with a multiple antimicrobial resistance (MAR) index ranging from 0.39 to 0.56, and a significant presence of class 1 (500-1100 bp) and class 2 (250-700 bp) integrons, indicating their potential risk to both fish and human populations. Our results underscore the role of aquatic environment as a repository for virulent and multidrug-resistant Aeromonas spp., emphasizing the imperative for prudent antimicrobial usage and regular monitoring of antimicrobial resistance (AMR) in these environments.

The common bean (Phaseolus vulgaris L.) plays a significant economic and social role in Brazil. However, the national average yield remains relatively low, largely because most bean cultivation is undertaken by small-scale farmers. In this context, biological nitrogen fixation (BNF) is an effective strategy for improving crop yield. Therefore, it is important to identify novel rhizobial strains well suited to local climatic conditions. This study used Phaseolus vulgaris as a trap plant in soils from three distinct conservation areas (Ponta Grossa, Ortigueira, and Londrina) within Paraná State, Brazil. The soil chemical analysis revealed that the pH values in the Ponta Grossa and Ortigueira regions were low, whereas the Ortigueira region exhibited elevated aluminum levels. A total of 94 strains were obtained from the nodules of plants and subjected to analysis for their morphological and genetic properties. No nodules were observed in the Ortigueira region. In the Ponta Grossa region, most of the strains were identified as belonging to the genus Paraburkholderia, whereas all strains from Londrina were identified as Rhizobium. The 16S rRNA gene phylogenetic analysis revealed a high degree of genetic similarity between the Paraburkholderia and Rhizobium strains. These findings indicate that soil chemical properties (pH and aluminum level) and climate conditions may have a significant impact on the symbiotic association between rhizobia and common bean.

Aspergillus and Candida are ubiquitous fungi included in the group of high priority in the World Health Organization list of fungal pathogens. They are found in various ecosystems and the environmental role in increasing the resistance to antifungals has been shown. Thus, we aimed to determine the occurrence of Aspergillus spp. and Candida spp. pathogenic species in water samples from a coastal ecosystem from southern Brazil, and its antifungal susceptibility profile. Water samples were collected monthly at three environmental sites, over 25 months. Abiotic parameters of the water samples were analyzed as well as antifungal susceptibility. Aspergillus spp. and Candida spp. were detected in 44% (n = 33/75) and 40% (n = 30/75) respectively of the samples, totaling 67 and 96 isolates. Section Fumigati and C. parapsilosis were the most section/species isolated. Triazole resistance was detected in 3% of the Aspergillus spp. (2/67) and in 1% of the Candida spp. (1/96) isolates. Our study contributes with data showing that coastal aquatic environments can serve as a source of infection of resistant fungal isolates, proving the need for environmental surveillance and monitoring of fungal resistance in the One Health perspective.

Cowpea (Vigna unguiculata) is recognized as a promiscuous legume in its symbiotic relationships with rhizobia, capable of forming associations with a wide range of bacterial species. Our study focused on assessing the diversity of bacterial strains present in cowpea nodules when inoculated with soils from six indigenous lands of Mato Grosso do Sul state, Central-Western Brazil, comprising the Cerrado and the Pantanal biomes, which are known for their rich diversity. The DNA profiles (BOX-PCR) of 89 strains indicated great genetic diversity, with 20 groups and 23 strains occupying single positions, and all strains grouped at a final similarity level of only 25%. Further characterization using 16S rRNA gene sequencing revealed a diverse array of bacterial genera associated with the cowpea nodules. The strains (number in parenthesis) were classified into ten genera: Agrobacterium (47), Ancylobacter (2), Burkholderia (12), Ensifer (1), Enterobacter (1), Mesorhizobium (1), Microbacterium (1), Paraburkholderia (1), Rhizobium (22), and Stenotrophomonas (1), split into four different classes. Notably, only Ensifer, Mesorhizobium, Rhizobium, and Paraburkholderia are classified as rhizobia. Phylogenetic analysis was conducted based on the classes of the identified genera and the type strains of the closest species. Our integrated analyses, combining phenotypic, genotypic, and phylogenetic approaches, highlighted the significant promiscuity of cowpea in associating with a diverse array of bacteria within nodules, showcasing the Brazilian soils as a hotspot of bacterial diversity.

Parasitoid wasps act as natural biological control agents for several harmful insect species. However, there is a lack of information regarding the exogenous RNA viruses that infect parasitoids and may contribute to the success of their parasitism strategies. This study aimed to investigate the presence, abundance, and replication of known exogenous viruses in two parasitoid wasp species and their corresponding preys. Utilizing publicly available RNA deep-sequencing data, two previously validated viruses from the parasitoid Tetrastichus brontispae were assessed in the target beetles Brontispa longissima and Octodonta nipae from the same geographic region. This study revealed the presence of the iflavirus TbRV-3 in both T. brontispae and O. nipae-derived samples, suggesting a potential exchange of the virus between the parasitoid and its host. In addition, there is substantial evidence that the Halyomorpha halys virus infects the parasitoid Telenomus podisi. Thus, this study proposes a close evolutionary relationship between the HhV strain identified in the parasitoid Telenomus podisi and the original strain detected in the prey H. halys. The viral association between trophically related species, such as parasitoids and their hosts, is demonstrated using features such as abundance and the presence of double-stranded RNA, which serves as a proxy for virus replication. Therefore, RNA viruses may coexist at both trophic levels, conferring an evolutionary advantage to the parasitism strategy.

Methicillin-resistant Staphylococcus aureus (MRSA) is one of the leading causes of infection worldwide due to its antimicrobial resistance. Plant-derived essential oils (EOs) have undergone extensive observational and clinical research to explore their antimicrobial properties. The present study aimed to check mec A positive MRSA isolates using sequencing analysis, determination of chemical composition using gas chromatography-mass spectroscopy (GC-MS), antioxidant, and antimicrobial activity of Anethum graveolens and Piper betle EOs against the infectious agent MRSA. The result demonstrates a significant antibacterial activity of both essential oils against MRSA clinical isolates. GC-MS analysis of Piper betle showed (41.06%) 3-Allyl-6-methoxyphenol (Eugenol) as the major compound, whereas Anethum graveolens exhibited o-cymene (14.01%) abundantly. Piper betle essential oil retained appreciable levels of total phenolic (39.5 ± 10.9 mg/g of gallic acid equivalents) and flavonoid content (216 ± 145 mg quercetin equivalent/g), when compared to Anethum graveolens essential oil. A strong correlation was observed between antioxidant activity (DPPH, FRAP, and ABTS), total phenolic, and total flavonoid content in the Piper betle and displayed using principal component analysis (PCA) and a scatter matrix plot. Parallelly, clear morphological bacterial alterations were visualized by scanning electron microscopy after treating it with essential oils. MRSA showed malformed cell surfaces or broken cells with pore formation and septae. These findings imply that both essential oils are potential natural sources of antimicrobials against the MRSA superbug. They can also be used in combination therapies with other plant EOs or with traditional antibiotics to combat the rise of bacteria resistance.