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1.
BMC Bioinformatics ; 25(1): 228, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38956506

RESUMO

BACKGROUND: Fungi play a key role in several important ecological functions, ranging from organic matter decomposition to symbiotic associations with plants. Moreover, fungi naturally inhabit the human body and can be beneficial when administered as probiotics. In mycology, the internal transcribed spacer (ITS) region was adopted as the universal marker for classifying fungi. Hence, an accurate and robust method for ITS classification is not only desired for the purpose of better diversity estimation, but it can also help us gain a deeper insight into the dynamics of environmental communities and ultimately comprehend whether the abundance of certain species correlate with health and disease. Although many methods have been proposed for taxonomic classification, to the best of our knowledge, none of them fully explore the taxonomic tree hierarchy when building their models. This in turn, leads to lower generalization power and higher risk of committing classification errors. RESULTS: Here we introduce HiTaC, a robust hierarchical machine learning model for accurate ITS classification, which requires a small amount of data for training and can handle imbalanced datasets. HiTaC was thoroughly evaluated with the established TAXXI benchmark and could correctly classify fungal ITS sequences of varying lengths and a range of identity differences between the training and test data. HiTaC outperforms state-of-the-art methods when trained over noisy data, consistently achieving higher F1-score and sensitivity across different taxonomic ranks, improving sensitivity by 6.9 percentage points over top methods in the most noisy dataset available on TAXXI. CONCLUSIONS: HiTaC is publicly available at the Python package index, BIOCONDA and Docker Hub. It is released under the new BSD license, allowing free use in academia and industry. Source code and documentation, which includes installation and usage instructions, are available at https://gitlab.com/dacs-hpi/hitac .


Assuntos
Fungos , Aprendizado de Máquina , Fungos/genética , Fungos/classificação , DNA Espaçador Ribossômico/genética , Software
2.
Funct Integr Genomics ; 24(5): 145, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39196424

RESUMO

Cases of diphtheria, even in immunized individuals, are still reported in several parts of the world, including in Brazil. New outbreaks occur in Europe and other continents. In this context, studies on Corynebacterium diphtheriae infections are highly relevant, both for a better understanding of the pathogenesis of the disease and for controlling the circulation of clones and antimicrobial resistance genes. Here we present a case of cutaneous infection by multidrug-resistant Corynebacterium diphtheriae and provide its whole-genome sequencing. Genomic analysis revealed resistance genes, including tet(W), sul1, cmx, rpoB2, rbpA and mutation in rpoB. We performed phylogenetic analyzes and used the BRIG to compare the predicted resistance genes with those found in genomes from other significant isolates, including those associated with some outbreaks. Virulence factors such as spaD, srtBC, spaH, srtDE, surface-anchored pilus proteins (sapD), nonfimbrial adhesins (DIP0733, DIP1281, and DIP1621), embC and mptC (putatively involved in CdiLAM), sigA, dtxR and MdbA (putatively involved) in post-translational modification, were detected. We identified the CRISPR-Cas system in our isolate, which was classified as Type II-U based on the database and contains 15 spacers. This system functions as an adaptive immune mechanism. The strain was attributed to a new sequence type ST-928, and phylogenetic analysis confirmed that it was related to ST-634 of C. diphtheriae strains isolated in French Guiana and Brazil. In addition, since infections are not always reported, studies with the sequence data might be a way to complement and inform C. diphtheriae surveillance.


Assuntos
Sistemas CRISPR-Cas , Corynebacterium diphtheriae , Rifampina , Fatores de Virulência , Corynebacterium diphtheriae/genética , Corynebacterium diphtheriae/patogenicidade , Corynebacterium diphtheriae/efeitos dos fármacos , Humanos , Fatores de Virulência/genética , Rifampina/farmacologia , Mutação , Filogenia , Difteria/microbiologia , Genoma Bacteriano , Proteínas de Bactérias/genética , Farmacorresistência Bacteriana Múltipla/genética
3.
Eur J Clin Microbiol Infect Dis ; 43(1): 203-208, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37985550

RESUMO

We present a case of skin lesion caused by nontoxigenic Corynebacterium diphtheriae. Genomic taxonomy analyses corroborated the preliminary identification provided by mass spectrometry. The strain showed a susceptible phenotype with increased exposure to penicillin, the first drug of choice for the treatment. An empty type 1 class integron carrying only the sul1 gene, which encodes sulfonamide resistance, was found flanked by transposases. Virulence factors involved in adherence and iron uptake, as well as the CRISPR-Cas system, were predicted. MLST analysis revealed the ST-681, previously reported in French Guiana, a European territory.


Assuntos
Corynebacterium diphtheriae , Humanos , Corynebacterium diphtheriae/genética , Tipagem de Sequências Multilocus , Sequenciamento Completo do Genoma , Genômica , Ferro
4.
J Appl Microbiol ; 135(9)2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39257028

RESUMO

AIMS: Biofilms are complex microbial cell aggregates that attach to different surfaces in nature, industrial environments, or hospital settings. In photovoltaic panels (PVs), biofilms are related to significant energy conversion losses. In this study, our aim was to characterize the communities of microorganisms and the genes involved in biofilm formation. METHODS AND RESULTS: In this study, biofilm samples collected from a PV system installed in southeastern Brazil were analyzed through shotgun metagenomics, and the microbial communities and genes involved in biofilm formation were investigated. A total of 2030 different genera were identified in the samples, many of which were classified as extremophiles or producers of exopolysaccharides. Bacteria prevailed in the samples (89%), mainly the genera Mucilaginibacter, Microbacterium, Pedobacter, Massilia, and Hymenobacter. The functional annotation revealed >12 000 genes related to biofilm formation and stress response. Genes involved in the iron transport and synthesis of c-di-GMP and c-AMP second messengers were abundant in the samples. The pathways related to these components play a crucial role in biofilm formation and could be promising targets for preventing biofilm formation in the PV. In addition, Raman spectroscopy analysis indicated the presence of hematite, goethite, and ferrite, consistent with the mineralogical composition of the regional soil and metal-resistant bacteria. CONCLUSIONS: Taken together, our findings reveal that PV biofilms are a promising source of microorganisms of industrial interest and genes of central importance in regulating biofilm formation and persistence.


Assuntos
Bactérias , Biofilmes , Biofilmes/crescimento & desenvolvimento , Brasil , Bactérias/genética , Bactérias/classificação , Bactérias/metabolismo , Bactérias/isolamento & purificação , Metagenômica , Compostos Férricos/metabolismo , Microbiota , Minerais/metabolismo , Fontes de Energia Bioelétrica/microbiologia , Compostos de Ferro
5.
J Appl Microbiol ; 135(4)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38503568

RESUMO

AIMS: The purpose was to evaluate the antimicrobial activity of highly soluble polypyrrole (Hs-PPy), alone or combined with oxacillin, as well as its antibiofilm potential against methicillin-resistant Staphylococcus aureus strains. Furthermore, the in silico inhibitory mechanism in efflux pumps was also investigated. METHODS AND RESULTS: Ten clinical isolates of methicillin-resistant Staphylococcus aureus (MRSA) and two reference strains were used. Antimicrobial activity was determined by broth microdilution, and the combination effect with oxacillin was evaluated by the checkerboard assay. The biofilm formation capacity of MRSA and the interference of Hs-PPy were evaluated. The inhibitory action of Hs-PPy on the efflux pump was evaluated in silico through molecular docking. Hs-PPy showed activity against the isolates, with inhibitory action between 62.5 and 125 µg ml-1 and bactericidal action at 62.5 µg ml-1, as well as synergism in association with oxacillin. The isolates ranged from moderate to strong biofilm producers, and Hs-PPy interfered with the formation of this structure, but not with mature biofilm. There was no in silico interaction with the efflux protein EmrD, the closest homolog to NorA. CONCLUSIONS: Hs-PPy interferes with biofilm formation by MRSA, has synergistic potential, and is an efflux pump inhibitor.


Assuntos
Anti-Infecciosos , Staphylococcus aureus Resistente à Meticilina , Antibacterianos/farmacologia , Polímeros/farmacologia , Pirróis/farmacologia , Simulação de Acoplamento Molecular , Oxacilina/farmacologia , Anti-Infecciosos/farmacologia , Biofilmes , Testes de Sensibilidade Microbiana
6.
Curr Microbiol ; 81(10): 339, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39225833

RESUMO

Bacterial spores in materials and equipment pose significant biosecurity risks, making effective disinfection crucial. This study evaluated Ortho-phthalaldehyde (OPA) and a quaternary ammonia-glutaraldehyde solution (AG) for inactivating spores of Bacillus thuringiensis (BT), B. cereus (BC), and two strains of B. velezensis (BV1 and BV2). Spores of BV1 and BT were treated with 22.5 mg/m3 OPA by dry fumigation or 1 mg/mL AG by spray for 20 min, according to the manufacturer's recommendation. As no sporicidal effect was observed, OPA was tested at 112.5 mg/m3 for 40 min, showing effectiveness for BT but not for BV1. Minimum bactericidal concentration (MBC) tests revealed higher MBC values for glutaraldehyde, prompting an overnight test with 112.5 mg/m3 OPA by dry fumigation and 50 mg/mL AG by spray, using formaldehyde as a control. AG reduced all Bacillus strains, but with limited sporicidal effect. OPA was sporicidal for BT and BV1 but not for BC and BV2, indicating a strain-dependent effect. Formaldehyde performed better overall but did not completely inactivate BV2 spores. Our findings suggest that OPA and AG have potential as formaldehyde replacements in wet disinfection procedures.


Assuntos
Bacillus thuringiensis , Bacillus , Desinfetantes , Glutaral , Esporos Bacterianos , Desinfetantes/farmacologia , Esporos Bacterianos/efeitos dos fármacos , Bacillus/efeitos dos fármacos , Bacillus/fisiologia , Glutaral/farmacologia , Bacillus thuringiensis/efeitos dos fármacos , Bacillus thuringiensis/fisiologia , Testes de Sensibilidade Microbiana , o-Ftalaldeído/farmacologia , Bacillus cereus/efeitos dos fármacos , Viabilidade Microbiana/efeitos dos fármacos , Desinfecção/métodos
7.
Adv Exp Med Biol ; 1443: 87-101, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38409417

RESUMO

Microbiotas are an adaptable component of ecosystems, including human ecology. Microorganisms influence the chemistry of their specialized niche, such as the human gut, as well as the chemistry of distant surroundings, such as other areas of the body. Metabolomics based on mass spectrometry (MS) is one of the primary methods for detecting and identifying small compounds generated by the human microbiota, as well as understanding the functional significance of these microbial metabolites. This book chapter gives basic knowledge on the kinds of untargeted mass spectrometry as well as the data types that may be generated in the context of microbiome study. While data analysis remains a barrier, the emphasis is on data analysis methodologies and integrative analysis, particularly the integration of microbiome sequencing data. Mass spectrometry (MS)-based techniques have resurrected culture methods for studying the human gut microbiota, filling in the gaps left by high-throughput sequencing methods in terms of culturing minor populations.


Assuntos
Microbioma Gastrointestinal , Microbiota , Humanos , Espectrometria de Massas/métodos , Metabolômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala
8.
Adv Exp Med Biol ; 1443: 243-256, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38409425

RESUMO

Proteomics has grown in importance in molecular sciences because it gives vital information on protein identification, expression levels, and alteration. Cancer is one of the world's major causes of death and is the major focus of much research. Cancer risk is determined by hereditary variables as well as the body's immunological condition. Probiotics have increasing medical importance due to their therapeutic influence on the human body in the prevention and treatment of numerous chronic illnesses, including cancer, with no adverse effects. Several anticancer, anti-inflammatory, and chemopreventive probiotics are studied using different proteomic approaches like two-dimensional gel electrophoresis, liquid chromatography-mass spectrometry, and matrix-assisted laser desorption/ionization mass spectrometry. To gain relevant information about probiotic characteristics, data from the proteomic analysis are evaluated and processed using bioinformatics pipelines. Proteomic studies showed the significance of different proteomic approaches in characterization, comparing strains, and determination of oxidative stress of different probiotics. Moreover, proteomic approaches identified different proteins that are involved in glucose metabolism and the formation of cell walls or cell membranes, and the differences in the expression of critical enzymes in the HIF-1 signaling pathway, starch, and sucrose metabolism, and other critical metabolic pathways.


Assuntos
Neoplasias , Probióticos , Humanos , Proteínas de Bactérias/metabolismo , Proteômica/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Probióticos/uso terapêutico , Neoplasias/prevenção & controle , Eletroforese em Gel Bidimensional
9.
Int J Mol Sci ; 25(17)2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39273410

RESUMO

Amelogenesis imperfecta (AI) is a genetic disease characterized by poor formation of tooth enamel. AI occurs due to mutations, especially in AMEL, ENAM, KLK4, MMP20, and FAM83H, associated with changes in matrix proteins, matrix proteases, cell-matrix adhesion proteins, and transport proteins of enamel. Due to the wide variety of phenotypes, the diagnosis of AI is complex, requiring a genetic test to characterize it better. Thus, there is a demand for developing low-cost, noninvasive, and accurate platforms for AI diagnostics. This case-control pilot study aimed to test salivary vibrational modes obtained in attenuated total reflection fourier-transformed infrared (ATR-FTIR) together with machine learning algorithms: linear discriminant analysis (LDA), random forest, and support vector machine (SVM) could be used to discriminate AI from control subjects due to changes in salivary components. The best-performing SVM algorithm discriminates AI better than matched-control subjects with a sensitivity of 100%, specificity of 79%, and accuracy of 88%. The five main vibrational modes with higher feature importance in the Shapley Additive Explanations (SHAP) were 1010 cm-1, 1013 cm-1, 1002 cm-1, 1004 cm-1, and 1011 cm-1 in these best-performing SVM algorithms, suggesting these vibrational modes as a pre-validated salivary infrared spectral area as a potential biomarker for AI screening. In summary, ATR-FTIR spectroscopy and machine learning algorithms can be used on saliva samples to discriminate AI and are further explored as a screening tool.


Assuntos
Amelogênese Imperfeita , Aprendizado de Máquina , Saliva , Humanos , Amelogênese Imperfeita/diagnóstico , Amelogênese Imperfeita/genética , Amelogênese Imperfeita/metabolismo , Saliva/metabolismo , Saliva/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Feminino , Estudos de Casos e Controles , Masculino , Algoritmos , Adulto , Máquina de Vetores de Suporte , Projetos Piloto , Análise Discriminante , Biomarcadores , Triagem/métodos , Adolescente , Adulto Jovem
10.
World J Microbiol Biotechnol ; 40(8): 235, 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38850338

RESUMO

Lactobacillus delbrueckii, a widely used lactic acid bacterium in the food industry, has been studied for its probiotic properties and reservoir of antibiotic-resistant genes, raising safety concerns for probiotic formulations and fermented products. This review consolidates findings from 60 articles published between 2012 and 2023, focusing on the global antibiotic resistance profile and associated genetic factors in L. delbrueckii strains. Resistance to aminoglycosides, particularly streptomycin, kanamycin, and gentamicin, as well as resistance to glycopeptides (vancomycin), fluoroquinolones (ciprofloxacin), and tetracyclines was predominant. Notably, although resistance genes have been identified, they have not been linked to mobile genetic elements, reducing the risk of dissemination. However, a significant limitation is the insufficient exploration of responsible genes or mobile elements in 80% of studies, hindering safety assessments. Additionally, most articles originated from Asian and Middle Eastern countries, with strains often isolated from fermented dairy foods. Therefore, these findings underscore the necessity for comprehensive analyses of new strains of L. delbrueckii for potential industrial and biotherapeutic applications and in combating the rise of antibiotic-resistant pathogens.


Assuntos
Antibacterianos , Lactobacillus delbrueckii , Probióticos , Probióticos/farmacologia , Lactobacillus delbrueckii/genética , Lactobacillus delbrueckii/efeitos dos fármacos , Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla/genética , Indústria Alimentícia , Microbiologia de Alimentos , Alimentos Fermentados/microbiologia
11.
Angiogenesis ; 26(1): 129-166, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36183032

RESUMO

Cancer cells are embedded within the tissue and interact dynamically with its components during cancer progression. Understanding the contribution of cellular components within the tumor microenvironment is crucial for the success of therapeutic applications. Here, we reveal the presence of perivascular GFAP+/Plp1+ cells within the tumor microenvironment. Using in vivo inducible Cre/loxP mediated systems, we demonstrated that these cells derive from tissue-resident Schwann cells. Genetic ablation of endogenous Schwann cells slowed down tumor growth and angiogenesis. Schwann cell-specific depletion also induced a boost in the immune surveillance by increasing tumor-infiltrating anti-tumor lymphocytes, while reducing immune-suppressor cells. In humans, a retrospective in silico analysis of tumor biopsies revealed that increased expression of Schwann cell-related genes within melanoma was associated with improved survival. Collectively, our study suggests that Schwann cells regulate tumor progression, indicating that manipulation of Schwann cells may provide a valuable tool to improve cancer patients' outcomes.


Assuntos
Neoplasias , Neuroglia , Humanos , Estudos Retrospectivos , Neuroglia/metabolismo , Células de Schwann/metabolismo , Células de Schwann/patologia , Pericitos , Microambiente Tumoral/fisiologia , Neoplasias/patologia
12.
Cell Immunol ; 384: 104661, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36621093

RESUMO

Multiple sclerosis is an autoimmune disease that affects the central nervous system. Because of its complexity and the difficulty to treat, searching for immunoregulatory responses that reduce the clinical signs of disease by non-aggressive mechanisms and without adverse effects is a scientific challenge. Herein we propose a protocol of oral tolerance induction that prevented and controlled MOG-induced experimental autoimmune encephalomyelitis (EAE) in C57BL/6 mice. The genetically modified strain HSP65-producing Lactococcus lactis was orally administered for 5 consecutive days either before or during disease development in mice. Both protocols of feeding HSP65 resulted in significant reduction in the clinical score of EAE. Frequencies of LAP+CD4+Foxp3- regulatory T cells were higher in spleens and inguinal lymph nodes of fed mice. In addition, intravital microscopy showed that adherence of leukocytes to venules in the spinal cord was reduced in orally treated mice. Oral treatment with HSP65-producing L.lactis prevented leukocytes to leave the secondary lymphoid organs, therefore they could not reach the central nervous system. Despite the inhibition of pathological immune response that drive EAE development, activated T cells were at normal frequencies suggesting that oral tolerance did not induce general immunosuppression, but it led to specific control of pathogenic T cells. Our results indicate a novel therapeutic strategy to prevent and control autoimmune diseases such as multiple sclerosis.


Assuntos
Encefalomielite Autoimune Experimental , Lactococcus lactis , Esclerose Múltipla , Camundongos , Animais , Camundongos Endogâmicos C57BL , Medula Espinal
13.
BMC Microbiol ; 23(1): 364, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38008714

RESUMO

BACKGROUND: Probiotics have gained attention for their potential maintaining gut and immune homeostasis. They have been found to confer protection against pathogen colonization, possess immunomodulatory effects, enhance gut barrier functionality, and mitigate inflammation. However, a thorough understanding of the unique mechanisms of effects triggered by individual strains is necessary to optimize their therapeutic efficacy. Probiogenomics, involving high-throughput techniques, can help identify uncharacterized strains and aid in the rational selection of new probiotics. This study evaluates the potential of the Escherichia coli CEC15 strain as a probiotic through in silico, in vitro, and in vivo analyses, comparing it to the well-known probiotic reference E. coli Nissle 1917. Genomic analysis was conducted to identify traits with potential beneficial activity and to assess the safety of each strain (genomic islands, bacteriocin production, antibiotic resistance, production of proteins involved in host homeostasis, and proteins with adhesive properties). In vitro studies assessed survival in gastrointestinal simulated conditions and adhesion to cultured human intestinal cells. Safety was evaluated in BALB/c mice, monitoring the impact of E. coli consumption on clinical signs, intestinal architecture, intestinal permeability, and fecal microbiota. Additionally, the protective effects of both strains were assessed in a murine model of 5-FU-induced mucositis. RESULTS: CEC15 mitigates inflammation, reinforces intestinal barrier, and modulates intestinal microbiota. In silico analysis revealed fewer pathogenicity-related traits in CEC15, when compared to Nissle 1917, with fewer toxin-associated genes and no gene suggesting the production of colibactin (a genotoxic agent). Most predicted antibiotic-resistance genes were neither associated with actual resistance, nor with transposable elements. The genome of CEC15 strain encodes proteins related to stress tolerance and to adhesion, in line with its better survival during digestion and higher adhesion to intestinal cells, when compared to Nissle 1917. Moreover, CEC15 exhibited beneficial effects on mice and their intestinal microbiota, both in healthy animals and against 5FU-induced intestinal mucositis. CONCLUSIONS: These findings suggest that the CEC15 strain holds promise as a probiotic, as it could modulate the intestinal microbiota, providing immunomodulatory and anti-inflammatory effects, and reinforcing the intestinal barrier. These findings may have implications for the treatment of gastrointestinal disorders, particularly some forms of diarrhea.


Assuntos
Proteínas de Escherichia coli , Mucosite , Probióticos , Camundongos , Humanos , Animais , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Inflamação , Probióticos/uso terapêutico
14.
Microb Pathog ; 180: 106164, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37211264

RESUMO

Candida haemulonii is an emergent infectious pathogen that affects human presenting comorbidities and/or immunodepression. Little is known about other possible hosts. For the first time, this fungus was found causing a cutaneous infection in a snake, Boa constrictor, characterized by scale opacity and several ulcerative lesions. This C. haemulonii was isolated, identified using molecular techniques and a phylogenetic study, and had its growth totally inhibited by all the drugs tested; however, no fungicide effect was seen for fluconazole and itraconazole. The B. constrictor clinical signals subsided after a treatment using a biogenic silver nanoparticle-based ointment. These findings, along with the B. constrictor presence near human habitats, warn for the necessity of wildlife health monitoring for emergent and opportunistic diseases in peri-urban environments.


Assuntos
Boidae , Candidíase , Nanopartículas Metálicas , Animais , Humanos , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Candida , Filogenia , Candidíase/microbiologia , Prata/farmacologia , Fluconazol/farmacologia , Fluconazol/uso terapêutico , Testes de Sensibilidade Microbiana
15.
Microb Ecol ; 86(4): 2488-2501, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37326636

RESUMO

Biofilms are complex microecosystems with valuable ecological roles that can shelter a variety of microorganisms. Spirochetes from the genus Leptospira have been observed to form biofilms in vitro, in rural environments, and in the kidneys of reservoir rats. The genus Leptospira is composed of pathogenic and non-pathogenic species, and the description of new species is ongoing due to the advent of whole genome sequencing. Leptospires have increasingly been isolated from water and soil samples. To investigate the presence of Leptospira in environmental biofilms, we collected three distinct samples of biofilms formed in an urban setting with poor sanitation: Pau da Lima, in Salvador, Bahia, Brazil. All biofilm samples were negative for the presence of pathogenic leptospires via conventional PCR, but cultures containing saprophytic Leptospira were identified. Whole genomes were generated and analyzed for twenty isolates obtained from these biofilms. For species identification, we used digital DNA-DNA hybridization (dDDH) and average nucleotide identity (ANI) analysis. The obtained isolates were classified into seven presumptive species from the saprophytic S1 clade. ANI and dDDH analysis suggest that three of those seven species were new. Classical phenotypic tests confirmed the novel isolated bacteria as saprophytic Leptospira. The isolates presented typical morphology and ultrastructure according to scanning electron microscopy and formed biofilms under in vitro conditions. Our data indicate that a diversity of saprophytic Leptospira species survive in the Brazilian poorly sanitized urban environment, in a biofilm lifestyle. We believe our results contribute to a better understanding of Leptospira biology and ecology, considering biofilms as natural environmental reservoirs for leptospires.


Assuntos
Leptospira , Leptospirose , Animais , Ratos , Leptospira/genética , Leptospirose/microbiologia , Brasil , Biofilmes , DNA
16.
Appl Microbiol Biotechnol ; 107(14): 4593-4603, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37219572

RESUMO

Caseous lymphadenitis (CLA), an infectious disease caused by Corynebacterium pseudotuberculosis in small ruminants, is highly prevalent worldwide. Economic losses have already been associated with the disease, and little is known about the host-pathogen relationship associated with the disease. The present study aimed to perform a metabolomic study of the C. pseudotuberculosis infection in goats. Serum samples were collected from a herd of 173 goats. The animals were classified as controls (not infected), asymptomatic (seropositives but without detectable CLA clinical signs), and symptomatic (seropositive animals presenting CLA lesions), according to microbiological isolation and immunodiagnosis. The serum samples were analyzed using nuclear magnetic resonance (1H-NMR), nuclear Overhauser effect spectroscopy (NOESY), and Carr-Purcell-Meiboom-Gill (CPMG) sequences. The NMR data were analyzed using chemometrics, and principal component analysis (PCA) and partial least square discriminant analysis (PLS-DA) were performed to discover specific biomarkers responsible for discrimination between the groups. A high dissemination of the infection by C. pseudotuberculosis was observed, being 74.57% asymptomatic and 11.56% symptomatic. In the evaluation of 62 serum samples by NMR, the techniques were satisfactory in the discrimination of the groups, being also complementary and mutually confirming, demonstrating possible biomarkers for the infection by the bacterium. Twenty metabolites of interest were identified by NOESY and 29 by CPMG, such as tryptophan, polyunsaturated fatty acids, formic acid, NAD+, and 3-hydroxybutyrate, opening promising possibilities for the use of these results in new therapeutic, immunodiagnosis, and immunoprophylactic tools, as well as for studies of the immune response against C. pseudotuberculosis. KEY POINTS: • Sixty-two samples from healthy, CLA asymptomatic, and symptomatic goats were screened • Twenty metabolites of interest were identified by NOESY and 29 by CPMG • 1H-NMR NOESY and CPMG were complementary and mutually confirming.


Assuntos
Infecções por Corynebacterium , Corynebacterium pseudotuberculosis , Linfadenite , Animais , Corynebacterium pseudotuberculosis/metabolismo , Cabras/microbiologia , Linfadenite/diagnóstico , Linfadenite/veterinária , Linfadenite/microbiologia , Infecções por Corynebacterium/diagnóstico , Infecções por Corynebacterium/veterinária , Infecções por Corynebacterium/microbiologia , Espectroscopia de Ressonância Magnética
17.
Phytopathology ; 113(7): 1360-1364, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36703497

RESUMO

Cashew (Anacardium occidentale) angular leaf spot is caused by pigmented and non-pigmented strains of Xanthomonas citri pv. anacardii, which have been isolated from infected plants in Brazil. The disease symptoms can be observed in leaves, stems, and fruits. Given that infection in young fruits results in fruits unsuitable for commercialization, angular leaf spot represents a serious threat to the cashew crop in Brazil. Here, we report the genomic sequencing of seven pigmented strains of X. citri pv. anacardii, obtained from the leaves of cashew trees from São Paulo state, Brazil, in 2009. The construction of the libraries was carried out according to the manufacturer, and whole-genome sequencing was performed using the Illumina HiSeq 2500 platform. Genome size, number of coding sequences, largest contig length, and N50 ranged from 4,996,984 to 5,003,485 bp, 4,621 to 4,643 bp, 212,513 to 362,232 bp, and 113,582 to 141,003 bp, respectively. GC content and RNA numbers were 64.68% and 54, respectively, for all strains. ANIm and dDDH analyses showed values above 99.5 and 92.1% among these strains and the non-pigmented pathotype strain of X. citri pv. anacardii (IBSBF2579PT). A maximum likelihood tree built with 2,708 core genes grouped all X. citri pv. anacardii strains in the same clade, with a 100% bootstrap. These resources will contribute in a relevant way to help understand the ecological, taxonomic, evolutionary, pathogenicity, and virulence aspects of X. citri pv. anacardii, which will be useful for the study and development of techniques for managing cashew angular leaf spot.


Assuntos
Anacardium , Xanthomonas , Doenças das Plantas , Brasil
18.
Indian J Med Res ; 157(4): 293-303, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37102510

RESUMO

Background & objectives: During the COVID-19 pandemic, the death rate was reportedly 5-8 fold lower in India which is densely populated as compared to less populated western countries. The aim of this study was to investigate whether dietary habits were associated with the variations in COVID-19 severity and deaths between western and Indian population at the nutrigenomics level. Methods: In this study nutrigenomics approach was applied. Blood transcriptome of severe COVID-19 patients from three western countries (showing high fatality) and two datasets from Indian patients were used. Gene set enrichment analyses were performed for pathways, metabolites, nutrients, etc., and compared for western and Indian samples to identify the food- and nutrient-related factors, which may be associated with COVID-19 severity. Data on the daily consumption of twelve key food components across four countries were collected and a correlation between nutrigenomics analyses and per capita daily dietary intake was investigated. Results: Distinct dietary habits of Indians were observed, which may be associated with low death rate from COVID-19. Increased consumption of red meat, dairy products and processed foods by western populations may increase the severity and death rate by activating cytokine storm-related pathways, intussusceptive angiogenesis, hypercapnia and enhancing blood glucose levels due to high contents of sphingolipids, palmitic acid and byproducts such as CO2 and lipopolysaccharide (LPS). Palmitic acid also induces ACE2 expression and increases the infection rate. Coffee and alcohol that are highly consumed in western countries may increase the severity and death rates from COVID-19 by deregulating blood iron, zinc and triglyceride levels. The components of Indian diets maintain high iron and zinc concentrations in blood and rich fibre in their foods may prevent CO2 and LPS-mediated COVID-19 severity. Regular consumption of tea by Indians maintains high high-density lipoprotein (HDL) and low triglyceride in blood as catechins in tea act as natural atorvastatin. Importantly, regular consumption of turmeric in daily food by Indians maintains strong immunity and curcumin in turmeric may prevent pathways and mechanisms associated with SARS-CoV-2 infection and COVID-19 severity and lowered the death rate. Interpretation & conclusions: Our results suggest that Indian food components suppress cytokine storm and various other severity related pathways of COVID-19 and may have a role in lowering severity and death rates from COVID-19 in India as compared to western populations. However, large multi-centered case-control studies are required to support our current findings.


Assuntos
COVID-19 , Ingredientes de Alimentos , Humanos , Nutrigenômica , Dióxido de Carbono , Lipopolissacarídeos , Pandemias , Síndrome da Liberação de Citocina , Ácido Palmítico , SARS-CoV-2 , Dieta/métodos , Comportamento Alimentar , Zinco , Chá , Ferro , Triglicerídeos
19.
An Acad Bras Cienc ; 95(suppl 2): e20230617, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38055447

RESUMO

Sexually Transmitted Infections (STIs) are a public health burden rising in developed and developing nations. The World Health Organization estimates nearly 374 million new cases of curable STIs yearly. Global efforts to control their spread have been insufficient in fulfilling their objective. As there is no vaccine for many of these infections, these efforts are focused on education and condom distribution. The development of vaccines for STIs is vital for successfully halting their spread. The field of immunoinformatics is a powerful new tool for vaccine development, allowing for the identification of vaccine candidates within a bacterium's genome and allowing for the design of new genome-based vaccine peptides. The goal of this review was to evaluate the usage of immunoinformatics in research focused on non-viral STIs, identifying fields where research efforts are concentrated. Here we describe gaps in applying these techniques, as in the case of Treponema pallidum and Trichomonas vaginalis.


Assuntos
Infecções Sexualmente Transmissíveis , Trichomonas vaginalis , Vacinas , Humanos , Vacinologia , Infecções Sexualmente Transmissíveis/prevenção & controle
20.
Genomics ; 114(6): 110517, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36306958

RESUMO

Aspergillus welwitschiae causes bole rot disease in sisal (Agave sisalana and related species) which affects the production of natural fibers in Brazil, the main worldwide producer of sisal fibers. This fungus is a saprotroph with a broad host range. Previous research established A. welwitschiae as the only causative agent of bole rot in the field, but little is known about the evolution of this species and its strains. In this work, we performed a comparative genomics analysis of 40 Aspergillus strains. We show the conflicting molecular identity of this species, with one sisal-infecting strain sharing its last common ancestor with Aspergillus niger, having diverged only 833 thousand years ago. Furthermore, our analysis of positive selection reveals sites under selection in genes coding for siderophore transporters, Sodium­calcium exchangers, and Phosphatidylethanolamine-binding proteins (PEBPs). Herein, we discuss the possible impacts of these gene functions on the pathogenicity in sisal.


Assuntos
Agave , Agave/genética , Brasil , Aspergillus/genética
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