Bacterial biofilms are increasing its tolerance to conventional antimicrobial treatments. In this context biofilm formation becomes an important target to control pathogenic bacteria. Arthropods are known to be an important source of natural products; however, investigations exploring the biological activities of arthropod eggs are scarce. So, in this study we investigated the antibiofilm activity of the Mediterranean flour moth Anagasta kuehniella compounds against Staphylococcus epidermidis. The antibiofilm activity of organic and aqueous extractions performed on the eggs was assessed using the crystal violet method and scanning electron microscopy (SEM). Egg's aqueous extract (AE) inhibits up to 65 % biofilm formation by S. epidermidis. Heat and enzymatic treatments indicated that activity was related to protein. A partial purified active fraction (F9) was obtained by size exclusion chromatography and SDS-PAGE were performed using AE and F9. Mass spectrometry was used to identify the proteins in the F9. SEM analysis showed this fraction inhibits bacterial aggregates in treated S. epidermidis biofilms without alteration on bacterial cell morphology. Our results showed that proteins present in A. kuehniella eggs inhibit biofilm formation without killing S. epidermidis and reinforces the idea that arthropods are a potential source of natural products useful for biotechnology.

Plastics are widely utilized due to their versatility and durability. However, their accumulation poses a significant negative impact on the environment. The biodegradation of plastics is a slow process driven by abiotic factors and microbial enzymes. Studies have demonstrated that the larvae of the insect Galleria mellonella L. (Linnaeus 1758) biodegrade plastics at a rate exceeding that of microbial biodegradation. Nevertheless, the enzymes involved in plastic biodegradation within the larvae remain poorly studied. Given the availability of the G. mellonella genome in public databases, this study aimed to identify enzyme sequences in the insect's genome that are homologous to microbial enzymes known for their roles in plastic biodegradation. A total of 40 microbial enzyme sequences were selected from the literature and compared with the G. mellonella genome. Four insect enzymes were further analyzed through molecular modeling and docking to examine their three-dimensional structures, catalytic regions, and interactions with substrates. Notably, two esterases, FE4-like isoform X2 and FE4-like, were identified as candidates for biodegrading BHET and PU. To date, no esterase from G. mellonella has been reported as being active in plastic biodegradation. This study represents pioneering research employing bioinformatics approaches to uncover enzyme sequences in the genome of G. mellonella associated with plastic biodegradation.

Rapid biodegradation of low-density polyethylene (LDPE) by the insect larvae Galleria mellonella motivates the understanding of the role of the larval microbiota in this process. In this study, the effect of the LDPE ingestion by these animals under normal or reduced microbiota conditions was evaluated and a rigorous protocol was designed to assess the gut and salivary glands microbial communities from G. mellonella larvae submitted to different diets. Microbiota depleted larvae showed decreased of LDPE consumption and their frass and cocoon presented changes in chemical features when compared to control larvae. High-throughput sequencing of 16S rRNA gene and ITS region reveled that beeswax-fed and LDPE-fed larvae exhibit similar bacterial community compositions, with an increased abundance of LDPE-biodegrading genera (Rhizobium and Sphingobium) in gut and salivary glands. Additionally, we report for the first time the presence of archaeal communities in both organs, and fungal communities in the salivary glands of G. mellonella. In beeswax-fed larvae, the phylum Ascomycota, known to include genera associated with PE biodegradation, was predominant. Another novel finding is the identification of the ciliate Aspidisca in salivary glands of beeswax-fed larvae, previously reported as a hydrocarbon-biodegrader. Functional prediction analysis demonstrated several enzymes potentially involved in LDPE digestion and allowed us to propose a hypothetical PE biodegradation pathway in G. mellonella larvae, involving a synergistic interaction between larval and microbial enzymes. Our results suggest that feeding on LDPE or beeswax selectively enriches microorganisms associated with hydrocarbons and LDPE biodegradation, indicating the innate capability of G. mellonella to biodegrade plastics.

The skin is the first host tissue that the tick mouthparts, tick saliva, and a tick-borne pathogen contact during feeding. Tick salivary glands have evolved a complex and sophisticated pharmacological arsenal, consisting of bioactive molecules, to assist blood feeding and pathogen transmission. In this work, persulcatin, a multifunctional molecule that targets keratinocyte function and hemostasis, was identified from Ixodes persulcatus female ticks. The recombinant persulcatin was expressed and purified and is a 25-kDa acidic protein with 2 Kunitz-type domains. Persulcatin is a classical tight-binding competitive inhibitor of proteases, targeting plasmin ( K i : 28 nM) and thrombin ( K i : 115 nM). It blocks plasmin generation on keratinocytes and inhibits their migration and matrix protein degradation; downregulates matrix metalloproteinase 2 and matrix metalloproteinase 9; and causes a delay in blood coagulation, endothelial cell activation, and thrombin-induced fibrinocoagulation. It interacts with exosite I of thrombin and reduces thrombin-induced endothelial cell permeability by inhibiting vascular endothelial-cadherin disruption. The multifaceted roles of persulcatin as an inhibitor and modulator within the plasminogen-plasmin system and thrombin not only unveil further insights into the intricate mechanisms governing wound healing but also provide a fresh perspective on the intricate interactions between ticks and their host organisms.

Ticks are important ectoparasites with a worldwide distribution. The most commonly used method for tick control involves the use of acaricides. The main problem is that its indiscriminate use has led to the selection of resistant tick populations. Glutathione transferases (GSTs) are enzymes that play an important role in the detoxification of several types of compounds used in commercial tick control products. This work aims to find new bioactive molecules through in vitro assays with a panel of 160 molecules with putative inhibitory activity on the Rhipicephalus microplus GST enzyme (RmGST). Also, selected molecules were tested against GSTs from other tick species; Rhipicephalus decoloratus, Amblyomma variegatum, Rhipicephalus appendiculatus, and Haemaphysalis longicornis. The first screening on RmGST identified 30 compounds with the ability to modify the enzymatic activity of this enzyme. These compounds included different chemical families, like chalcones, diarylideneketones, flavone, thiazoles, thiourea, steroids, thiadiazines, indazoles, and hydrazine. The most potent compounds against RmGST belong to the diarylideneketones family with an inhibition concentration of 50% of activity (IC50) between 7-50 μM. Interestingly, one of the most potent compounds was also an inhibitor of the GST from other tick species. Experiments with R. microplus adults and larvae showed toxicity at 150 μM, suggesting a potential acaricidal effect of these molecules.

The obvious contrast between the remarkable durability and the high consumption of plastic products leads to the deposition of at least 100 million tons of plastics per year in nature. Since 2010, several studies have shown the potential of insect larvae to biodegrade different types of plastics, at higher rates than those reported for microorganisms. This review discusses a compilation of studies about the consumption and biodegradation of hydrocarbon-based plastics, particularly PE, PS, PP and PVC, by lepidopteran and coleopteran larvae. Insects of the Coleoptera order seem to have a better adaptation for PS biodegradation, while those of the Lepidoptera order can better biodegrade PE. Tenebrio molitor biomineralize PE and PS into CO2, and PVC into HCl; while Tenebrio obscurus and Zophobas atratus converts PE and PS into CO2, respectively. Plastic biodegradation by T. molitor has been shown to be dependent on microbiota, exception for PE. Similar PS and PE biodegradation profile has been shown for T. obscurus. PS, PP and PE biodegradation by Z. atratus is also reported to be microbial-dependent. For Galleria mellonella, microbial role on PE biodegradation is still controversial, but the PS metabolism was proved to be microbiota-independent. Advances in this field has stimulated new studies with other insect species, which need to be better explored. Uncovering and understanding the chemical processes behind the innate plastic biodegradation by insect larvae will open the perspective to new eco-friendly innovative biotechnological solutions for the challenge of plastic waste.

New ecosystems are being actively mined for new bioactive compounds. Because of the large amount of unexplored biodiversity, bacteria from marine environments are especially promising. Further, host-associated microbes are of special interest because of their low toxicity and compatibility with host health. Here, we identified and characterized biosynthetic gene clusters encoding antimicrobial compounds in host-associated enterococci recovered from fecal samples of wild marine animals remote from human-affected ecosystems. Putative biosynthetic gene clusters in the genomes of 22 Enterococcus strains of marine origin were predicted using antiSMASH5 and Bagel4 bioinformatic software. At least one gene cluster encoding a putative bioactive compound precursor was identified in each genome. Collectively, 73 putative antimicrobial compounds were identified, including 61 bacteriocins (83.56%), 10 terpenes (13.70%), and 2 (2.74%) related to putative nonribosomal peptides (NRPs). Two of the species studied, Enterococcus avium and Enterococcus mundtti, are rare causes of human disease and were found to lack any known pathogenic determinants but yet possessed bacteriocin biosynthetic genes, suggesting possible additional utility as probiotics. Wild marine animal-associated enterococci from human-remote ecosystems provide a potentially rich source for new antimicrobial compounds of therapeutic and industrial value and potential probiotic application.

Despite the increasing attention on the causes generating the observed gender gap in science and the efforts in resolving it, women are still underrepresented in academia, especially in STEM (science, technology, engineering, and mathematics) fi elds (Shauman 2017).This scenario is also observed in Brazil (Barros & Mourão 2020, Areas et al. 2020).Many factors can contribute to the observed gender gap in science, but maternity is certainly playing an important role (Sallee et al. 2016).Maternity leave, which in Brazil ranges from four to six months, often leads to a decrease in productivity, affecting women competitiveness for a few years after the birth of a child (Machado et al. 2019).For this reason, funding agencies and universities should consider maternity leave as a career break and create strategies to circumvent its negative effect in the evaluations of researchers' productivity.The Brazilian Lattes CV database (http://lattes.cnpq.br) is a successful model of scientifi c databases (Lane 2010).The Brazilian National Council for Scientifi c and Technological Development (CNPq) created the database to quantify academic productivity -it is the main source to evaluate researchers for promotions and grant funding.In May 2018, the Parent in

Trichomonas vaginalis is an amitochondriate protozoan and the agent of human trichomoniasis, the most prevalent non-viral sexually transmitted infection (STI) in the world. In this study we showed that 2,4-diamine-quinazoline derivative compound (PH100) kills T. vaginalis. PH100 showed activity against fresh clinical and American Type Culture Collection (ATCC) T. vaginalis isolates with no cytotoxicity against cells (HMVI, 3T3-C1 and VERO) and erythrocytes. In addition, PH100 showed synergistic action with metronidazole, indicating that these compounds act by different mechanisms. When investigating the mechanism of action of PH100 to ATCC 30236, apoptosis-like characteristics were observed, such as phosphatidylserine exposure, membrane alterations, and modulation of gene expression and activity of peptidases related to apoptosis. The apoptosis-like cell death features were not observed for the fresh clinical isolate treated with PH100 revealing distinct profiles. Our data revealed the heterogeneity among T. vaginalis isolates and contribute with the understanding of mechanisms of cell death in pathogenic eukaryotic organisms without mitochondria.

The coronavirus disease 2019 (COVID-19) pandemic is altering dynamics in academia, and people juggling remote work and domestic demands – including childcare – have felt impacts on their productivity. Female authors have faced a decrease in paper submission rates since the beginning of the pandemic period. The reasons for this decline in women’s productivity need to be further investigated. Here, we analyzed the influence of gender, parenthood and race on academic productivity during the pandemic period based on a survey answered by 3,345 Brazilian academics from various knowledge areas and research institutions. Productivity was assessed by the ability to submit papers as planned and to meet deadlines during the initial period of social isolation in Brazil. The findings revealed that male academics – especially those without children – are the least affected group, whereas Black women and mothers are the most impacted groups. These impacts are likely a consequence of the well-known unequal division of domestic labor between men and women, which has been exacerbated during the pandemic. Additionally, our results highlight that racism strongly persists in academia, especially against Black women. The pandemic will have long-term effects on the career progression of the most affected groups. The results presented here are crucial for the development of actions and policies that aim to avoid further deepening the gender gap in academia.

The reuse of agroindustrial waste has been the subject of several studies since they present rich chemical composition and their disposal generates costs to industries and harmful potential to the environment. Compounds present in soybean residues may have a potential antibiofilm activity, a property still very little explored in this raw material. The seek for active compounds against biofilms, has been extremely important, since they represent a challenge in clinical and industrial environments. Thus, this study aimed to evaluate the potential antibiofilm and antimicrobial activities of extracts obtained from soybeans processing residues against Staphylococcus aureus, Staphylococcus epidermidis, and Pseudomonas aeruginosa. Antibacterial and antibiofilm activities of two crude extracts were evaluated using absorbance (620 nm), colony-forming units (CFU) counting, and the crystal violet method, respectively. The safety of these compounds was assessed using the alternative model Caenorhabditis elegans. The extract obtained from fragments of the grain and stalks (E1) had its chemical characterization investigated and was submitted fractionation by ultrafiltration. The proteomic and metabolomic analysis of an active fraction was performed using liquid chromatography and mass spectrometry. E1 (4 mg/mL) inhibited 75 % of the S. epidermidis biofilm formation with no inhibition of bacterial growth. Antibiofilm activity of E1 was lost when it was submitted to a heat treatment, while the enzymatic treatment with proteinase K led to a loss of 30 % in the activity of the extract, suggesting that the antibiofilm molecules may be of protein origin. When submitted to the ultrafiltration process, the antibiofilm activity was observed mainly when two fractions (fraction 50 kDa (R50) and fraction <10 kDa (F10 ')) were combined, suggesting that the biological activity is dependent on the combination of the active molecules. The metabolomic analysis of F10 ' indicated the presence of flavonoids, lipids, peptides, organic compounds and nucleosides while in the proteomic analysis of R50 a total of 19 proteins were identified. The extract E1 and the active fraction (R50+F10 ') showed low toxicity in C. elegans. This work shows that soybeans agroindustrial residues may be a potential source of molecules with activity against bacterial biofilms.

In this study, we analyzed 340 whole genomes of SARS-CoV-2, which were sampled between April and November 2020 in 33 cities of Rio Grande do Sul, South Brazil. We demonstrated the circulation of two novel emergent lineages, VUI-NP13L and VUI-NP13L-like, and five major lineages that had already been assigned (B.1.1.33, B.1.1.28, P.2, B.1.91, B.1.195). P.2 and VUI-NP13L demonstrated a massive spread in October 2020. Constant and consistent genomic surveillance is crucial to identify newly emerging SARS-CoV-2 lineages in Brazil and to guide decision making in the Brazilian Public Healthcare System.

Genomic surveillance of SARS-CoV-2 is paramount for understanding viral dynamics, contributing to disease control. This study analyzed SARS-CoV-2 genomic diversity in Rio Grande do Sul (RS), Brazil, including the first reported case in each Regional Health Coordination and cases from three epidemic peaks. Ninety SARS-CoV-2 genomes from RS were sequenced and analyzed through comparison with SARS-CoV-2 datasets available in GISAID for phylogenetic inference and mutation analysis. Among the first reported cases, we found the following lineages: B.1 (33.3%), B.1.1.28 (26.7%), B.1.1 (13.3%), B.1.1.33 (10.0%), and A (6.7%), evidencing SARS-CoV-2 introduction by both international origin and community-driven transmission. We found predominance of B.1.1.33 (50.0%) and B.1.1.28 (35.0%) during the first epidemic peak (July-August 2020), emergence of P.2 (55.6%) in the second peak (November-December 2020), and massive spread of P.1 and related sequences (78.4%), such as P.1-like-II, P.1.1 and P.1.2 in the third peak (February-April, 2021). Eighteen novel mutation combinations were found among P.1 genomes, and 22 different spike mutations and/or deletions among P.1 and related sequences. This study shows the dispersion of SARS-CoV-2 lineages in Southern Brazil and describes SARS-CoV-2 diversity during three epidemic peaks, highlighting the spread of P.1 and the high genetic diversity of currently circulating lineages. Genomic monitoring of SARS-CoV-2 is essential to guide health authorities' decisions to control COVID-19 in Brazil.

ABSTRACTSouth Brazil has been the novel epicenter of Coronavirus Disease 2019 (COVID-19) in 2021, accounting for the greatest number of cumulative cases and deaths (per 100 thousand inhabitants in a week) worldwide. In this study, we analyzed 340 whole genomes of SARS-CoV-2, which were sampled between April and November 2020 in 33 cities in South Brazil. We demonstrated the circulation of two novel emergent lineages, described here as P.4 and P.4.1 (provisionally termed VUI-NP13L), and seven lineages that had already been assigned (B.1.1.33, B.1.1.28, P.2, B.1.91, B.1.1.94, B.1.195 and B.1.212). P.2 and P.4.1 demonstrated massive spread from approximately September/October 2020. Constant and consistent genomic surveillance is crucial to identify newly emerging SARS-CoV-2 lineages in Brazil and to guide decision making in the Brazilian Public Healthcare System.

The aim of this study was to select and identify thermophilic bacteria from Caatinga biome (Brazil) able to produce thermoactive keratinases and characterize the keratinase produced by the selected isolate. After enrichment in keratin culture media, an Anoxybacillus caldiproteolyticus PC2 was isolated. This thermotolerant isolate presents a remarkable feature producing a thermostable keratinase at 60°C. The partially purified keratinase, identified as a thermolysin-like peptidase, was active at a pH range of 5.0-10.0 with maximal activity at a temperature range of 50-80°C. The optimal activity was observed at pH 7.0 and 50-60°C. These characteristics are potentially useful for biotechnological purposes such as processing and bioconversion of keratin.

Rhipicephalus appendiculatus, the brown ear tick, is an important disease vector of livestock in eastern, central and southern Africa. Rhipicephalus appendiculatus acaricide resistance requires the search for alternative methods for its control. Cystatins constitute a superfamily of cysteine peptidase inhibitors vital for tick blood feeding and development. These inhibitors were proposed as antigens in anti-tick vaccines. In this work, we applied structural and biochemical approaches to characterize a new cystatin named R. appendiculatus cystatin 2a (Racys2a). Structural modeling showed that this new protein possesses characteristic type 2 cystatin motifs, besides conservation of other structural patterns along the protein. Peptidase inhibitory assays with recombinant Racys2a showed modulation of tick and host cathepsins involved in blood digestion and immune system responses, respectively. A heterologous tick challenge with R. appendiculatus in rabbits immunized with recombinant Rhipicephalus microplus cystatin 2c (rBmcys2c) was performed to determine cross-reactivity. Histological staining showed that rBmcys2c vaccination caused damage to the gut, salivary gland and ovary tissues in R. appendiculatus. Furthermore, cystatin vaccine reduced the number of fully engorged adult females in 11.5 %. Consequently, strategies to increase the protection rate are necessary, including the selection of two or more antigens to compose a vaccine cocktail.

Enterococci are commensals that proliferated as animals crawled ashore hundreds of millions of years ago. They are also leading causes of multidrug-resistant hospital-acquired infections. While most studies are driven by clinical interest, comparatively little is known about enterococci in the wild or the effect of human activity on them. Pharmaceutical pollution and runoff from other human activities are encroaching widely into natural habitats. To assess their reach into remote habitats, we investigated the identity, genetic relatedness, and presence of specific traits among 172 enterococcal isolates from wild Magellanic penguins. Four enterococcal species, 18 lineage groups, and different colonization patterns were identified. One Enterococcus faecalis lineage, sequence type 475 (ST475), was isolated from three different penguins, making it of special interest. Its genome was compared to those of other E. faecalis sequence types (ST116 and ST242) recovered from Magellanic penguins, as well as to an existing phylogeny of E. faecalis isolated from diverse origins over the past 100 years. No penguin-derived E. faecalis strains were closely related to dominant clinical lineages. Most possessed intact CRISPR defenses, few mobile elements, and antibiotic resistances limited to those intrinsic to the species and lacked pathogenic features conveyed by mobile elements. Interestingly, plasmids were identified in penguin isolates that also had been reported for other marine mammals. Enterococci isolated from penguins showed limited anthropogenic impact, indicating that they are likely representative of those naturally circulating in the ecosystem inhabited by the penguins. These findings establish an important baseline for detecting the encroachment of human activity into remote planetary environments. IMPORTANCE Enterococci are host-associated microbes that have an unusually broad range, from the built hospital environment to the guts of insects and other animals in remote locations. Despite their occurrence in the guts of animals for hundreds of millions of years, we know little about the properties that confer this range or how anthropogenic activities may be introducing new selective forces. Magellanic penguins live at the periphery of human habitation. It was of interest to examine enterococci from these animals for the presence of antibiotic resistance and other markers reflective of anthropogenic selection. Diverse enterococcal lineages found discount the existence of a single well-adapted intrinsic penguin-specific species. Instead, they appear to be influenced by a carnivorous lifestyle and enterococci present in the coastal sea life consumed. These results indicate that currently, the penguin habitat remains relatively free of pollutants that select for adaptation to human-derived stressors.