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1.
Res Vet Sci ; 179: 105396, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39213744

RESUMO

Although diphtheria is a vaccine-preventable disease, numerous cases are still reported around the world, as well as outbreaks in countries, including European ones. Species of the Corynebacterium diphtheriae complex are potentially toxigenic and, therefore, must be considered given the possible consequences, such as the circulation of clones and transmission of antimicrobial resistance and virulence genes. Recently, Corynebacterium rouxii was characterized and included among the valid species of the complex. Therefore, two cases of C. rouxii infection arising from infections in domestic animals are presented here. We provide molecular characterization, phylogenetic analyses, genome sequencing, and CRISPR-Cas analyses to contribute to a better understanding of the molecular bases, pathogenesis, and epidemiological monitoring of this species, which is still little studied. We confirmed its taxonomic position with genome sequencing and in silico analysis and identified the ST-918 for both strains. The clinical isolates were sensitive resistance to benzylpenicillin and rifampin. Antimicrobial resistance genes, including tetB, rpoB2, and rbpA genes, were predicted. The bla and ampC genes were not found. Several virulence factors were also detected, including adhesion, iron uptake systems, gene regulation (dtxR), and post-translational modification (MdbA). Finally, one prophage and the Type I-E CRISPR-Cas system were identified.


Assuntos
Antibacterianos , Infecções por Corynebacterium , Corynebacterium , Doenças do Cão , Filogenia , Rifampina , Animais , Corynebacterium/genética , Corynebacterium/efeitos dos fármacos , Doenças do Cão/microbiologia , Cães , Rifampina/farmacologia , Infecções por Corynebacterium/veterinária , Infecções por Corynebacterium/microbiologia , Antibacterianos/farmacologia , Genoma Bacteriano , Farmacorresistência Bacteriana/genética , Penicilinas/farmacologia
2.
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
3.
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
4.
PeerJ ; 12: e16513, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38313017

RESUMO

Background: Corynebacterium pseudotuberculosis is a zoonotic Gram-positive bacterial pathogen known to cause different diseases in many mammals, including lymph node abscesses in camels. Strains from biovars equi and ovis of C. pseudotuberculosis can infect camels. Comparative genomics could help to identify features related to host adaptation, and currently strain Cp162 from biovar equi is the only one from camel with a sequenced genome. Methods: In this work, we compared the quality of three genome assemblies of strain Cp162 that used data from the DNA sequencing platforms SOLiD v3 Plus, IonTorrent PGM, and Illumina HiSeq 2500 with an optical map and investigate the unique features of this strain. For this purpose, we applied comparative genomic analysis on the different Cp162 genome assembly versions and included other 129 genomes from the same species. Results: Since the first version of the genome, there was an increase of 88 Kbp and 121 protein-coding sequences, a decrease of pseudogenes from 139 to 53, and two inversions and one rearrangement corrected. We identified 30 virulence genes, none associated to the camel host, and the genes rpob2 and rbpA predicted to confer resistance to rifampin. In comparison to 129 genomes of the same species, strain Cp162 has four genes exclusively present, two of them code transposases and two truncated proteins, and the three exclusively absent genes lysG, NUDIX domain protein, and Hypothetical protein. All 130 genomes had the rifampin resistance genes rpob2 and rbpA. Our results found no unique gene that could be associated with tropism to camel host, and further studies should include more genomes and genome-wide association studies testing for genes and SNPs.


Assuntos
Corynebacterium pseudotuberculosis , Animais , Ovinos/genética , Corynebacterium pseudotuberculosis/genética , Camelus/genética , Genoma Bacteriano/genética , Estudo de Associação Genômica Ampla , Rifampina , Análise de Sequência de DNA
5.
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
6.
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
7.
Res Microbiol ; 174(7): 104086, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37307910

RESUMO

Salmonella Typhimurium is an important agent of foodborne diseases. In Peru, the emergence of multidrug-resistant isolates of S. Typhimurium from the food chain could be linked to guinea pig farming as a potential reservoir and their uncontrolled antibiotic treatment against salmonellosis. In this study, we performed the sequencing, genomic diversity, and characterization of resistance elements transmitted by isolates from farm and meat guinea pigs. The genomic diversity and antimicrobial resistance of S. Typhimurium isolates were performed using nucleotide similarity, cgMLST, serotyping, phylogenomic analyses, and characterization of resistance plasmids. We found at least four populations of isolates from farm guinea pigs and four populations from meat guinea pigs without finding isolated transmission between both resources. Genotypic resistance to antibiotics was observed in at least 50% of the isolates. Among the farm guinea pig isolates, ten were found to be resistant to nalidixic acid, and two isolates exhibited multidrug resistance to aminoglycosides, tetracycline-fluoroquinolone (carrying strA-strB-tetA-tetB genes and gyrA S83F mutation), or trimethoprim-sulfonamide (carrying AaadA1-drfA15-sul1 genes). Additionally, two isolates from the meat source were resistant to fluoroquinolones (one of which had enrofloxacin resistance). The transmissible resistance plasmids with insertion sequences (IS) such as IncI-gamma-K1-ISE3-IS6, IncI1-I (alpha)-IS21-Tn10, and Col (pHAD28) were commonly found in isolates belonging to the HC100-9757 cluster from both guinea pigs and human hosts. Altogether, our work provides resistance determinants profiles and Salmonella sp. circulating lineages using WGS data that can promote better sanitary control and adequate antimicrobial prescription.

8.
PeerJ ; 11: e14895, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36919166

RESUMO

Background: Corynebacterium silvaticum is a pathogenic, gram-positive bacterial species that causes caseous lymphadenitis in wild boars, domestic pigs and roe deer in Western Europe. It can affect animal production and cause zoonosis. Genome analysis has suggested that one strain from Portugal and one from Austria could probably produce the diphtheria toxin (DT), which inhibits protein synthesis and can cause death. Methods: To further investigate the species genetic diversity and probable production of DT by Portuguese strains, eight isolates from this country were sequenced and compared to 38 public ones. Results: Strains from Portugal are monophyletic, nearly identical, form a unique cluster and have 27 out of 36 known Corynebacterium virulence or niche factors. All of them lack a frameshift in the tox gene and were suggested to produce DT. A phylogenetic analysis shows that the species has diverged into two clades. Clade 1 is composed of strains that were suggested to have the ability to produce DT, represented by the monophyletic strains from Portugal and strain 05-13 from Austria. Clade 2 is composed of strains unable to produce DT due to a frameshifted tox gene. The second clade is represented by strains from Austria, Germany and Switzerland. Ten genome clusters were detected, in which strains from Germany are the most diverse. Strains from Portugal belong to an exclusive cluster. The pangenome has 2,961 proteins and is nearly closed (α = 0.968). Exclusive genes shared by clusters 1 and 2, and Portuguese strains are probably not related to disease manifestation as they share the same host but could play a role in their extra-host environmental adaptation. These results show the potential of the species to cause zoonosis, possibly diphtheria. The identified clusters, exclusively shaded genes, and exclusive STs identified in Portugal could be applied in the identification and epidemiology of the species.


Assuntos
Cervos , Toxina Diftérica , Suínos , Animais , Toxina Diftérica/genética , Portugal/epidemiologia , Filogenia , Cervos/metabolismo , Corynebacterium , Sus scrofa/metabolismo , Zoonoses
9.
Gene ; 855: 147131, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36539044

RESUMO

Staphylococcus aureus is the main etiological agent of mastitis in small ruminants worldwide. This disease has a difficult cure and possible relapse, leading to significant economic losses in production, milk quality and livestock. This study performed comparative genomic analyses between 73 S. aureus genomes from different hosts (human, bovine, pig and others). This work isolated and sequenced 12 of these genomes from ovine. This study contributes to the knowledge of genomic specialization and the role of specific genes in establishing infection in ovine mastitis-associated S. aureus. The genomes of S. aureus isolated from sheep maintained a higher representation when grouped with clonal complexes 130 and 133. The genomes showed high genetic similarity, the species pan-genome consisting of 4200 genes (central = 2008, accessory = 1559 and unique = 634). Among these, 277 unique genes were related to the genomes isolated from sheep, with 39.6 % as hypothetical proteins, 6.4 % as phages, 6.4 % as toxins, 2.9 % as transporters, and 44.7 % as related to other proteins. Furthermore, at the pathogen level, they showed 80 genes associated with virulence factors and 19 with antibiotic resistance shared in almost all isolates. Although S. aureus isolated from ovine showed susceptibility to antimicrobials in vitro, ten genes were predicted to be associated with antibiotic inactivation and efflux pump, suggesting resistance to gentamicin and penicillin. This work may contribute to identifying genes acquired by horizontal transfer and their role in host adaptation, virulence, bacterial resistance, and characterization of strains affecting ovine.


Assuntos
Mastite Bovina , Infecções Estafilocócicas , Feminino , Animais , Bovinos , Ovinos/genética , Humanos , Suínos , Fatores de Virulência/genética , Staphylococcus aureus/genética , Adaptação ao Hospedeiro , Infecções Estafilocócicas/genética , Infecções Estafilocócicas/veterinária , Infecções Estafilocócicas/microbiologia , Ruminantes/genética , Genômica , Sequências Repetitivas Dispersas , Mastite Bovina/genética , Mastite Bovina/microbiologia
10.
Antibiotics (Basel) ; 11(9)2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-36139949

RESUMO

Salmonella Typhimurium is associated with foodborne diseases worldwide, including in Peru, and its emerging antibiotic resistance (AMR) is now a global public health problem. Therefore, country-specific monitoring of the AMR emergence is vital to control this pathogen, and in these aspects, whole genome sequence (WGS)­based approaches are better than gene-based analyses. Here, we performed the antimicrobial susceptibility test for ten widely used antibiotics and WGS-based various analyses of 90 S. Typhimurium isolates (human, animal, and environment) from 14 cities of Peru isolated from 2000 to 2017 to understand the lineage and antimicrobial resistance pattern of this pathogen in Peru. Our results suggest that the Peruvian isolates are of Typhimurium serovar and predominantly belong to sequence type ST19. Genomic diversity analyses indicate an open pan-genome, and at least ten lineages are circulating in Peru. A total of 48.8% and 31.0% of isolates are phenotypically and genotypically resistant to at least one antibiotic, while 12.0% are multi-drug resistant (MDR). Genotype−phenotype correlations for ten tested drugs show >80% accuracy, and >90% specificity. Sensitivity above 90% was only achieved for ciprofloxacin and ceftazidime. Two lineages exhibit the majority of the MDR isolates. A total of 63 different AMR genes are detected, of which 30 are found in 17 different plasmids. Transmissible plasmids such as lncI-gamma/k, IncI1-I(Alpha), Col(pHAD28), IncFIB, IncHI2, and lncI2 that carry AMR genes associated with third-generation antibiotics are also identified. Finally, three new non-synonymous single nucleotide variations (SNVs) for nalidixic acid and eight new SNVs for nitrofurantoin resistance are predicted using genome-wide association studies, comparative genomics, and functional annotation. Our analysis provides for the first time the WGS-based details of the circulating S. Typhimurium lineages and their antimicrobial resistance pattern in Peru.

11.
PeerJ ; 10: e12662, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35190783

RESUMO

BACKGROUND: Within the pathogenic bacterial species Corynebacterium genus, six species that can produce diphtheria toxin (C. belfantii, C. diphtheriae, C. pseudotuberculosis, C. rouxii, C. silvaticum and C. ulcerans) form a clade referred to as the C. diphtheria complex. These species have been found in humans and other animals, causing diphtheria or other diseases. Here we show the results of a genome scale analysis to identify positive selection in protein-coding genes that may have resulted in the adaptations of these species to their ecological niches and suggest drug and vaccine targets. METHODS: Forty genomes were sampled to represent species, subspecies or biovars of Corynebacterium. Ten phylogenetic groups were tested for positive selection using the PosiGene pipeline, including species and biovars from the C. diphtheria complex. The detected genes were tested for recombination and had their sequences alignments and homology manually examined. The final genes were investigated for their function and a probable role as vaccine or drug targets. RESULTS: Nineteen genes were detected in the species C. diphtheriae (two), C. pseudotuberculosis (10), C. rouxii (one), and C. ulcerans (six). Those were found to be involved in defense, translation, energy production, and transport and in the metabolism of carbohydrates, amino acids, nucleotides, and coenzymes. Fourteen were identified as essential genes, and six as virulence factors. Thirteen from the 19 genes were identified as potential drug targets and four as potential vaccine candidates. These genes could be important in the prevention and treatment of the diseases caused by these bacteria.


Assuntos
Corynebacterium diphtheriae , Difteria , Vacinas , Humanos , Animais , Corynebacterium diphtheriae/genética , Difteria/prevenção & controle , Filogenia , Corynebacterium
12.
Rev Bras Parasitol Vet ; 30(4): e013121, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34852155

RESUMO

The objective of this study was to provide the first report of resistance of Haemonchus contortus to monepantel in sheep in Espírito Santo. The study was conducted in a property with history of monepantel use since 2014 and register of low efficacy in studies conducted over the past few years with fecal egg count reduction test. Lambs born on the property (males and females aged approximately 100 days) were selected and after eggs per gram of feces (EPG) analysis on fecal samples, these were divided into two groups: a group treated with monepantel (2.5 mg / Kg) and a control group without anthelmintic treatment. Seven days later, the animals were euthanized to recover parasites from the gastrointestinal tract. The efficacy of the treatment was 61.35% against H. contortus, thus proving that anthelmintic resistance to monepantel was present.


Assuntos
Anti-Helmínticos , Hemoncose , Haemonchus , Doenças dos Ovinos , Aminoacetonitrila/análogos & derivados , Animais , Anti-Helmínticos/farmacologia , Anti-Helmínticos/uso terapêutico , Brasil , Resistência a Medicamentos , Fezes , Feminino , Hemoncose/tratamento farmacológico , Hemoncose/veterinária , Masculino , Contagem de Ovos de Parasitas/veterinária , Ovinos , Doenças dos Ovinos/tratamento farmacológico
13.
Rev Bras Parasitol Vet ; 30(2): e000221, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34076042

RESUMO

Sixty-two fecal samples of capybara (Hydrochoerus hydrochaeris) living in eight conservation units (CUs) across the state of Espírito Santo, southeastern Brazil, were assessed for the presence of eggs of liver flukes via sedimentation. Fasciola hepatica eggs were found in 37.1% (23/62) of the samples. Positive samples were found in six CUs (75%), three CUs located in the southern region of the state and three others in the metropolitan region of the capital city of Vitória. Identification of Fasciola hepatica eggs collected from capybara fecal samples were based on morphology, and confirmed using molecular methods. Our results suggest that capybaras may serve as a wild reservoir host for F. hepatica, possibly contributing to the epidemiology and geographic range expansion of this zoonotic parasite across its vast range of distribution in South America.


Assuntos
Fasciola hepatica , Fasciolíase , Doenças dos Roedores , Animais , Brasil , Fasciolíase/diagnóstico , Fasciolíase/epidemiologia , Fasciolíase/veterinária , Fezes , Roedores
14.
Gene ; 795: 145781, 2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-34153410

RESUMO

The Bifidobacterium longum 51A strain of isolated from feces of a healthy child, has demonstrated probiotic properties by in vivo and in vitro studies, which may be assigned to its production of metabolites such as acetate. Thus, through the study of comparative genomics, the present work sought to identify unique genes that might be related to the production of acetate. To perform the study, the DNA strain was sequenced using Illumina HiSeq technology, followed by assembly and manual curation of coding sequences. Comparative analysis was performed including 19 complete B. longum genomes available in Genbank/NCBI. In the phylogenetic analysis, the CECT 7210 and 157F strains of B. longum subsp. infantis aggregated within the subsp. longum cluster, suggesting that their taxonomic classification should be reviewed. The strain 51A of B. longum has 26 unique genes, six of which are possibly related to carbohydrate metabolism and acetate production. The phosphoketolase pathway from B. longum 51A showed a difference in acetyl-phosphate production. This result seems to corroborate the analysis of their unique genes, whose presence suggests the strain may use different sources of carbohydrates that allow a greater production of acetate and consequently offer benefits to the host health.


Assuntos
Acetatos/metabolismo , Bifidobacterium longum/genética , Bifidobacterium longum/metabolismo , Metabolismo dos Carboidratos/genética , Genes Bacterianos , Probióticos/metabolismo , Sequência de Bases , Bifidobacterium longum/classificação , Criança , Simulação por Computador , Fezes/microbiologia , Genômica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Filogenia , Análise de Sequência de DNA
15.
PeerJ ; 9: e11079, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33854845

RESUMO

BACKGROUND: Lactobacillus crispatus is the dominant species in the vaginal microbiota associated with health and considered a homeostasis biomarker. Interestingly, some strains are even used as probiotics. However, the genetic mechanisms of L. crispatus involved in the control of the vaginal microbiome and protection against bacterial vaginosis (BV) are not entirely known. To further investigate these mechanisms, we sequenced and characterized the first four L. crispatus genomes from vaginal samples from Brazilian women and used genome-wide association study (GWAS) and comparative analyses to identify genetic mechanisms involved in healthy or BV conditions and selective pressures acting in the vaginal microbiome. METHODS: The four genomes were sequenced, assembled using ten different strategies and automatically annotated. The functional characterization was performed by bioinformatics tools comparing with known probiotic strains. Moreover, it was selected one representative strain (L. crispatus CRI4) for in vitro detection of phages by electron microscopy. Evolutionary analysis, including phylogeny, GWAS and positive selection were performed using 46 public genomes strains representing health and BV conditions. RESULTS: Genes involved in probiotic effects such as lactic acid production, hydrogen peroxide, bacteriocins, and adhesin were identified. Three hemolysins and putrescine production were predicted, although these features are also present in other probiotic strains. The four genomes presented no plasmids, but 14 known families insertion sequences and several prophages were detected. However, none of the mobile genetic elements contained antimicrobial resistance genes. The genomes harbor a CRISPR-Cas subtype II-A system that is probably inactivated due to fragmentation of the genes csn2 and cas9. No genomic feature was associated with a health condition, perhaps due to its multifactorial characteristic. Five genes were identified as under positive selection, but the selective pressure remains to be discovered. In conclusion, the Brazilian strains investigated in this study present potential protective properties, although in vitro and in vivo studies are required to confirm their efficacy and safety to be considered for human use.

16.
An Acad Bras Cienc ; 93(2): e20200945, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33681877

RESUMO

Bacterial vaginosis (BV) has been considered as dysbiosis state whose etiology is not fully understood. This condition affects a large number of women of reproductive age and its study has been highly relevant due to the growing association of BV with and gynecological and obstetric complications and diseases, in addition to a greater susceptibility to sexually transmitted diseases, including HIV. The vaginal microbiota composition presents high variability among different ethnic groups of women, although, generally, the prevalence of lactobacilli species has been reported. Several studies suggest they may play a protective role, especially Lactobacillus crispatus whose population is typically present in low proportions in women with BV. This review article describes the contributions and limitations of genomic approaches in elucidating protective characteristics and mechanisms associated with colonization and persistence of lactobacilli strains. Although some genetic features were associated with resilience of L. crispatus during BV, furher studies are required to uncover their functions.


Assuntos
Microbiota , Vaginose Bacteriana , Feminino , Genômica , Humanos , Lactobacillus/genética , Microbiota/genética , Vaginose Bacteriana/genética
17.
Data Brief ; 34: 106746, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33532526

RESUMO

The genus Klebsiella comprises species that cause nosocomial and community-acquired infections. A dataset was created to compile the sequence type (ST) and capsule type (K-locus) information predicted for 172 worldwide isolates of Klebsiella spp. whose complete genomes could be retrieved from the GenBank (NCBI) repository. The dataset also includes information related to one multidrug-resistant strain (B31) isolated from a patient who was admitted to an intensive care unit in the Northeast region of Brazil. This strain was phenotypically characterized and submitted to whole-genome sequencing and comparative genomics analysis as we recently reported [1]. The dataset also compiles information on Pathogenicity Islands (PIs), Resistance Islands (RIs) and Miscellaneous Islands (MIS) present in the genome of strain B31. The information provided here may support outbreak prevention policies and future epidemiological studies involving Klebsiella spp.

18.
Braz J Microbiol ; 52(1): 245-250, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32965626

RESUMO

Serratia marcescens are gram-negative bacteria found in several environmental niches, including the plant rhizosphere and patients in hospitals. Here, we present the genome of Serratia marcescens strain N4-5 (=NRRL B-65519), which has a size of 5,074,473 bp (664-fold coverage) and contains 4840 protein coding genes, 21 RNA genes, and an average G + C content of 59.7%. N4-5 harbours a plasmid of 11,089 bp and 43.5% G + C content that encodes six unique CDS repeated 2.5× times totalling 13 CDS. Our genome assembly and manual curation uncovered the insertion of two extra copies of the 5S rRNA gene in the assembled sequence, which was confirmed by PCR and Sanger sequencing to be a misassembly. This artefact was subsequently removed from the final assembly. The occurrence of extra copies of the 5S rRNA gene was also observed in most complete genomes of Serratia spp. deposited in public databases in our comparative analysis. These elements, which also occur naturally, can easily be confused with true genetic variation. Efforts to discover and correct assembly artefacts should be made in order to generate genome sequences that represent the biological truth underlying the studied organism. We present the genome of N4-5 and discuss genes potentially involved in biological control activity against plant pathogens and also the possible mechanisms responsible for the artefact we observed in our initial assembly. This report raises awareness about the extra copies of the 5S rRNA gene in sequenced bacterial genomes as they may represent misassemblies and therefore should be verified experimentally.


Assuntos
Genoma Bacteriano , Serratia marcescens/classificação , Serratia marcescens/genética , Sequenciamento Completo do Genoma , Composição de Bases , Agentes de Controle Biológico , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
19.
Gene ; 772: 145386, 2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33373662

RESUMO

The emergence of community acquired infections increases the public health concern on K. pneumoniae and closely related bacteria among which antimicrobial resistance spreads. We report a multidrug-resistant K. pneumoniae isolate, B31, of a patient infected in the community and admitted to an intensive care unit in Northeast Brazil. Antimicrobial susceptibility and genome information were thoroughly investigated to characterize B31 in front of 172 sequenced strains of different countries. Assigned to the Sequence Type 15, which is globally spread, B31 presented extended spectrum beta-lactamase, tigecycline and ciprofloxacin resistance. Genome sequencing revealed most resistance genes being carried by plasmids with high dissemination potential. The absence of main virulence factors, like yersiniabactin and colibactin, apparently suggests a mild pathogenic strain which, on the contrary, persisted and caused severe infection in a previously healthy patient. The present study contributes to unveil the unclear genomic scenario of virulent and multidrug-resistant K. pneumoniae in Brazil.


Assuntos
Infecções Comunitárias Adquiridas/microbiologia , Farmacorresistência Bacteriana Múltipla , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/classificação , Sequenciamento Completo do Genoma/métodos , Adulto , Ciprofloxacina/farmacologia , Feminino , Genoma Bacteriano , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Klebsiella pneumoniae/genética , Tipagem de Sequências Multilocus , Plasmídeos/genética , Tigeciclina/farmacologia
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