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1.
Gene ; 723: 144134, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31589960

RESUMO

Viral kinases are known to undergo autophosphorylation and also phosphorylate viral and host substrates. Viral kinases have been implicated in various diseases and are also known to acquire host kinases for mimicking cellular functions and exhibit virulence. Although substantial analyses have been reported in the literature on diversity of viral kinases, there is a gap in the understanding of sequence and structural similarity among kinases from different classes of viruses. In this study, we performed a comprehensive analysis of protein kinases encoded in viral genomes. Homology search methods have been used to identify kinases from 104,282 viral genomic datasets. Serine/threonine and tyrosine kinases are identified only in 390 viral genomes. Out of seven viral classes that are based on nature of genetic material, only viruses having double-stranded DNA and single-stranded RNA retroviruses are found to encode kinases. The 716 identified protein kinases are classified into 63 subfamilies based on their sequence similarity within each cluster, and sequence signatures have been identified for each subfamily. 11 clusters are well represented with at least 10 members in each of these clusters. Kinases from dsDNA viruses, Phycodnaviridae which infect green algae and Herpesvirales that infect vertebrates including human, form a major group. From our analysis, it has been observed that the protein kinases in viruses belonging to same taxonomic lineages form discrete clusters and the kinases encoded in alphaherpesvirus form host-specific clusters. A comprehensive sequence and structure-based analysis enabled us to identify the conserved residues or motifs in kinase catalytic domain regions across all viral kinases. Conserved sequence regions that are specific to a particular viral kinase cluster and the kinases that show close similarity to eukaryotic kinases were identified by using sequence and three-dimensional structural regions of eukaryotic kinases as reference. The regions specific to each viral kinase cluster can be used as signatures in the future in classifying uncharacterized viral kinases. We note that kinases from giant viruses Marseilleviridae have close similarity to viral oncogenes in the functional regions and in putative substrate binding regions indicating their possible role in cancer.


Assuntos
Proteínas Quinases/química , Proteínas Quinases/genética , Vírus/classificação , Domínio Catalítico , Biologia Computacional/métodos , Bases de Dados de Proteínas , Variação Genética , Fosforilação , Filogenia , Proteínas Quinases/metabolismo , Homologia de Sequência de Aminoácidos , Proteínas Virais/química , Proteínas Virais/genética , Proteínas Virais/metabolismo , Fatores de Virulência/química , Fatores de Virulência/genética , Fatores de Virulência/metabolismo , Vírus/enzimologia , Vírus/patogenicidade
2.
BMC Genomics ; 20(1): 768, 2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31646960

RESUMO

BACKGROUND: The Hafnia genus is an opportunistic pathogen that has been implicated in both nosocomial and community-acquired infections. Although Hafnia is fairly often isolated from clinical material, its taxonomy has remained an unsolved riddle, and the involvement and importance of Hafnia in human disease is also uncertain. Here, we used comparative genomic analysis to define the taxonomy of Hafnia, identify species-specific genes that may be the result of ecological and pathogenic specialization, and reveal virulence-related genetic profiles that may contribute to pathogenesis. RESULTS: One complete genome sequence and 19 draft genome sequences for Hafnia strains were generated and combined with 27 publicly available genomes. We provided high-resolution typing methods by constructing phylogeny and population structure based on single-copy core genes in combination with whole genome average nucleotide identity to identify two distant Hafnia species (alvei and paralvei) and one mislabeled strain. The open pan-genome and the presence of numerous mobile genetic elements reveal that Hafnia has undergone massive gene rearrangements. Presence of species-specific core genomes associated with metabolism and transport suggests the putative niche differentiation between alvei and paralvei. We also identified possession of diverse virulence-related profiles in both Hafnia species., including the macromolecular secretion system, virulence, and antimicrobial resistance. In the macromolecular system, T1SS, Flagellum 1, Tad pilus and T6SS-1 were conserved in Hafnia, whereas T4SS, T5SS, and other T6SSs exhibited the evolution of diversity. The virulence factors in Hafnia are related to adherence, toxin, iron uptake, stress adaptation, and efflux pump. The identified resistance genes are associated with aminoglycoside, beta-lactam, bacitracin, cationic antimicrobial peptide, fluoroquinolone, and rifampin. These virulence-related profiles identified at the genomic level provide insights into Hafnia pathogenesis and the differentiation between alvei and paralvei. CONCLUSIONS: Our research using core genome phylogeny and comparative genomics analysis of a larger collection of strains provides a comprehensive view of the taxonomy and species-specific traits between Hafnia species. Deciphering the genome of Hafnia strains possessing a reservoir of macromolecular secretion systems, virulence factors, and resistance genes related to pathogenicity may provide insights into addressing its numerous infections and devising strategies to combat the pathogen.


Assuntos
Genoma Bacteriano , Hafnia/classificação , Hafnia/patogenicidade , Virulência , Sistemas de Secreção Bacterianos/genética , Hibridização Genômica Comparativa , Farmacorresistência Bacteriana/genética , Genótipo , Filogenia , Especificidade da Espécie , Fatores de Virulência/genética
3.
Life Sci ; 237: 116947, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31605708

RESUMO

AIMS: Pseudomonas aeruginosa is one of the leading causes of opportunistic and hospital-acquired infections worldwide, which is frequently linked with clinical treatment difficulties. Ibuprofen, a widely used non-steroidal anti-inflammatory drug, has been previously reported to exert antimicrobial activity with the specific mechanism. We hypothesized that inhibition of P. aeruginosa with ibuprofen is involved in the quorum sensing (QS) systems. MAIN METHODS: CFU was utilized to assessed the growth condition of P. aeruginosa. Crystal violent staining and acridine orange staining was used to evaluate the biofilm formation and adherence activity. The detection of QS virulence factors such as pyocyanin, elastase, protease, and rhamnolipids were applied to investigation the anti-QS activity of ibuprofen against P. aeruginosa. The production of 3-oxo-C12-HSL and C4-HSL was confirmed by liquid chromatography/mass spectrometry analysis. qRT-PCR was used to identify the QS-related gene expression. Furthermore, we explored the binding effects between ibuprofen and QS-associated proteins with molecular docking. KEY FINDINGS: Ibuprofen inhibits P. aeruginosa biofilm formation and adherence activity. And the inhibitory effects of ibuprofen on C4-HSL levels were concentration-dependent (p < 0.05), while it has no effect on 3-oxo-C12-HSL. Moreover, ibuprofen attenuates the production of virulence factors in P. aeruginosa (p < 0.05). In addition, the genes of QS system were decreased after the ibuprofen treatment (p < 0.05). Of note, ibuprofen was binding with LuxR, LasR, LasI, and RhlR at high binding scores. SIGNIFICANCE: The antibiofilm and anti-QS activity of ibuprofen suggest that it can be a candidate drug for the treatment of clinical infections with P. aeruginosa.


Assuntos
Proteínas de Bactérias/genética , Biofilmes/crescimento & desenvolvimento , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Ibuprofeno/farmacologia , Pseudomonas aeruginosa/genética , Percepção de Quorum/efeitos dos fármacos , Fatores de Virulência/genética , Anti-Inflamatórios não Esteroides/farmacologia , Biofilmes/efeitos dos fármacos , Humanos , Infecções por Pseudomonas/tratamento farmacológico , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/crescimento & desenvolvimento
4.
Mol Plant Microbe Interact ; 32(12): 1577-1580, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31618137

RESUMO

The Xanthomonas genus, comprises more than 30 species of gram-negative bacteria, most of which are pathogens of plants with high economic value, such as rice, common bean, and maize. Transcription activator-like effectors (TALEs), which act by regulating the host gene expression, are some of the major virulence factors of these bacteria. We present a novel tool to identify TALE genes in the genome of Xanthomonas strains and their respective targets. The analysis of the results obtained by TargeTALE in a proof-of-concept validation demonstrate that, at optimum setting, approximately 93% of the predicted target genes with available expression data were confirmed as upregulated during the infection, indicating that the tool might be useful for researchers in the field.


Assuntos
Genoma Bacteriano , Efetores Semelhantes a Ativadores de Transcrição , Xanthomonas , Proteínas de Bactérias/genética , Interações Hospedeiro-Patógeno/genética , Oryza/microbiologia , Efetores Semelhantes a Ativadores de Transcrição/genética , Fatores de Virulência/genética , Xanthomonas/genética
5.
World J Microbiol Biotechnol ; 35(9): 134, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31432266

RESUMO

Shiga toxin-producing Escherichia coli (STEC) are zoonotic pathogens and may induce severe diarrheagenic diseases in humans and other animals. Non-O157 STEC have been emerging as important pathogens causing outbreaks worldwide. Bacterial resistance to antimicrobials has become a global public health problem, which involves different ecological spheres, including animals. This study aimed to characterize the resistance to antimicrobials, plasmids and virulence, as well as the serotypes and phylogenetic groups in E. coli isolated from sheep in Brazil. A total of 57 isolates were obtained and showed different antimicrobial resistance profiles. Nineteen isolates presented acquired antimicrobial resistance genes (ARGs) (blaCTX-M-Gp9, qnrB, qnrS, oqxB, oqxA, tetA, tetB, tetC, sul1 and sul2) and plasmid families (F, FIA, FIB, I1, K, HI1 and ColE-like). The stx1, stx2 and ehxA virulence genes were detected by PCR, being 50 isolates (87.7%) classified as STEC. A great diversity of serotypes was detected, being O176:HNM the most predominant. Phylogenetic group E was the most prevalent, followed by B1, A and B2. To the best of our knowledge, this is the first report in the world of blaCTX-M-Gp9 (O75, O114, O100, O128ac and O176 serogroups), qnrB and oqxB genes in non-O157 STEC in healthy sheep. The results obtained in the present study call attention to the monitoring of antimicrobial-resistant non-O157 STEC harboring acquired ARGs worldwide and indicate a zoonotic risk due to the profile of virulence, resistance and serotype found.


Assuntos
Infecções por Escherichia coli/veterinária , Fezes/microbiologia , Doenças dos Ovinos/microbiologia , Escherichia coli Shiga Toxigênica/isolamento & purificação , Animais , Brasil , Infecções por Escherichia coli/microbiologia , Genes Bacterianos , Variação Genética , Genótipo , Técnicas de Genotipagem , Testes de Sensibilidade Microbiana , Filogenia , Plasmídeos/análise , Reação em Cadeia da Polimerase , Sorogrupo , Ovinos , Escherichia coli Shiga Toxigênica/efeitos dos fármacos , Escherichia coli Shiga Toxigênica/genética , Escherichia coli Shiga Toxigênica/patogenicidade , Fatores de Virulência/genética
6.
Microbiol Immunol ; 63(9): 350-358, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31407393

RESUMO

Kenya is endemic for cholera with different waves of outbreaks having been documented since 1971. In recent years, new variants of Vibrio cholerae O1 have emerged and have replaced most of the traditional El Tor biotype globally. These strains also appear to have increased virulence, and it is important to describe and document their phenotypic and genotypic traits. This study characterized 146 V. cholerae O1 isolates from cholera outbreaks that occurred in Kenya between 1975 and 2017. Our study reports that the 1975-1984 strains had typical classical or El Tor biotype characters. New variants of V. cholerae O1 having traits of both classical and El Tor biotypes were observed from 2007 with all strains isolated between 2015 and 2017 being sensitive to polymyxin B and carrying both classical and El Tor type ctxB. All strains were resistant to Phage IV and harbored rstR, rtxC, hlyA, rtxA and tcpA genes specific for El Tor biotype indicating that the strains had an El Tor backbone. Pulsed field gel electrophoresis (PFGE) genotyping differentiated the isolates into 14 pulsotypes. The clustering also corresponded with the year of isolation signifying that the cholera outbreaks occurred as separate waves of different genetic fingerprints exhibiting different genotypic and phenotypic characteristics. The emergence and prevalence of V. cholerae O1 strains carrying El Tor type and classical type ctxB in Kenya are reported. These strains have replaced the typical El Tor biotype in Kenya and are potentially more virulent and easily transmitted within the population.


Assuntos
Cólera/epidemiologia , Cólera/microbiologia , Surtos de Doenças , Vibrio cholerae O1/classificação , Vibrio cholerae O1/genética , Vibrio cholerae O1/isolamento & purificação , Proteínas de Bactérias/genética , Técnicas de Tipagem Bacteriana/métodos , Toxina da Cólera/genética , DNA Bacteriano/genética , Genótipo , Técnicas de Genotipagem , Humanos , Quênia/epidemiologia , Testes de Sensibilidade Microbiana , Fenótipo , Polimixina B/farmacologia , Vibrio cholerae O1/efeitos dos fármacos , Virulência/genética , Fatores de Virulência/genética
7.
Microbiol Res ; 228: 126306, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31422233

RESUMO

The mariner transposon family of Himar1 has been widely used for the random mutagenesis of bacteria to generate single insertions into the chromosome. Here, a versatile toolbox of mariner transposon derivatives was generated and applied to the functional genomics investigation of fish pathogen Edwardsiella piscicida. In this study, we combined the merits of the random mutagenesis of mariner transposon and common efficient reporter marker genes or regulatory elements, mCherry, gfp, luxAB, lacZ, sacBR, and PBAD and antibiotic resistance cassettes to construct a series of derivative transposon vectors, pMmch, pMKGR, pMCGR, pMXKGR, pMLKGR, pMSGR, and pMPR, based on the initial transposon pMar2xT7. The function and effectiveness of the modified transposons were verified by introducing them into E. piscicida EIB202. Based on the toolbox, a transposon insertion mutant library containing approximately 3.0 × 105 distinct mutants was constructed to explore the upstream regulators of esrB, the master regulator of the type III and type VI secretion systems (T3/T6SS) in E. piscicida. Following analysis by Con-ARTIST, ETAE_3474, annotated as fabR and involved in fatty acid metabolism, was screened out and identified as a novel regulator mediating T3SS and T6SS expression. In addition, the fabR mutants displayed critical virulence attenuation in turbot. Due to the broad-range host compatibility of mariner transposons, the newly built transposon toolbox can be applied for functional genomics studies in various bacteria.


Assuntos
Proteínas de Bactérias/genética , Elementos de DNA Transponíveis , Edwardsiella/genética , Regulação Bacteriana da Expressão Gênica/genética , Testes Genéticos/métodos , Genoma Bacteriano/genética , Animais , Mapeamento Cromossômico , Farmacorresistência Bacteriana/genética , Ácidos Graxos/metabolismo , Doenças dos Peixes/microbiologia , Biblioteca Gênica , Genes Reporter/genética , Genômica/métodos , Mutagênese Insercional/métodos , Fatores de Transcrição/genética , Sistemas de Secreção Tipo III/genética , Sistemas de Secreção Tipo VI/genética , Virulência , Fatores de Virulência/genética
8.
Microbiol Res ; 228: 126304, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31422235

RESUMO

Streptococcus suis (S. suis) is an important zoonotic pathogen that causes major economic losses in the pig industry worldwide. The S. suis cell division process is an integral part of its growth and reproduction, which is controlled by a complex regulatory network. Pyruvate dehydrogenase (PDH), which catalyzes the oxidative decarboxylation of pyruvate to form acetyl-CoA, while reducing NAD + to NADH, plays an important role in energy metabolism. Recently, we reported that pdh regulates virulence by reducing stress tolerance and biofilm formation in S. suis serotype 2. In this study, we found that deletion of the pdh gene in S. suis resulted in abnormal cell chains, plump morphology and abnormal localization of the Z rings, indicating that the knockout mutant is impaired in its ability to divide. In addition, the interaction between FtsZ and PDH in vitro was confirmed by ELISA, and qRT-PCR analysis revealed that the deletion of the pdh gene results in differential expression of the division-related genes ftsZ, ftsK, ftsl, zapA, divIC, pbp1a, rodA, mreD, and sepF. These results indicate that pdh is involved in the normal formation of Z rings and cell morphology during S. suis cell division.


Assuntos
Divisão Celular/genética , Divisão Celular/fisiologia , Complexo Piruvato Desidrogenase/genética , Streptococcus suis/citologia , Streptococcus suis/genética , Streptococcus suis/fisiologia , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/fisiologia , Proteínas do Citoesqueleto/genética , Deleção de Genes , Perfilação da Expressão Gênica , Regulação Bacteriana da Expressão Gênica , Técnicas de Inativação de Genes , Infecções Estreptocócicas/microbiologia , Infecções Estreptocócicas/veterinária , Streptococcus suis/patogenicidade , Suínos , Virulência , Fatores de Virulência/genética
9.
BMC Infect Dis ; 19(1): 744, 2019 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-31455296

RESUMO

BACKGROUND: Multidrug resistant (MDR) enterococci are important nosocomial pathogens causing serious problem in hospitalized patients. The aim of present study was to investigate the frequency of high-level aminoglycoside-resistant and vancomycin-resistant enterococci (VRE) and virulence encoding genes in enterococci isolated from hospitalized patients. METHODS: A total of 100 enterococci isolated from urine samples of hospitalized patients with symptomatic urinary tract infections were investigated for antimicrobial susceptibility, the frequency of aminoglycoside and vancomycin resistance genes (including aac (6')-Ie-aph (2")-Ia, aph (3')-IIIa, ant (4')-Ia, aph (2")-Ic, aph (2")-Ib, aph (2")-Id, ant (3″)-III, ant (6')-Ia, vanA, vanB and vanC) and virulence encoding genes (including gelE, PAI, esp, ace, cyl, hyl and sprE). RESULTS: Enterococcus faecalis species was identified as predominant enterococci (69%), followed by "other" Enterococcus species (21%) and E. faecium (10%). Ninety three percent of isolates were resistant to one or more antimicrobial agents, with the most frequent resistance found against tetracycline (86%), ciprofloxacin (73%) and quinupristin-dalfopristin (53%). Gentamicin and streptomycin resistance were detected in 50 and 34% of isolates, respectively. The most prevalent aminoglycoside resistance genes were ant (3″)-III (78%) and aph (3')-IIIa (67%). Vancomycin resistance was detected in 21% of isolates. All E. faecium isolates carried vanA gene, whereas, the vanB gene was not detected in Enterococcus species. The most frequent virulence gene was ace (88.6%), followed by esp (67.1%), PAI (45.5%) and sprE (41.7%). CONCLUSION: Our study revealed the high frequency of gentamycin resistance and VRE in E. faecium isolates, with a high prevalence and heterogeneity of virulence and resistance genes. Due to high frequency of MDR enterococci, it seems that the appropriate surveillance and control measures are essential to prevent the emergence and transmission of these isolates in hospitals.


Assuntos
Farmacorresistência Bacteriana/genética , Enterococcus/patogenicidade , Infecções por Bactérias Gram-Positivas/microbiologia , Infecções Urinárias/microbiologia , Fatores de Virulência/genética , Adulto , Aminoglicosídeos/farmacologia , Antibacterianos/farmacologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Enterococcus/efeitos dos fármacos , Enterococcus/genética , Gentamicinas/farmacologia , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Infecções por Bactérias Gram-Positivas/epidemiologia , Hospitalização , Humanos , Incidência , Irã (Geográfico) , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Infecções Urinárias/tratamento farmacológico , Infecções Urinárias/epidemiologia , Resistência a Vancomicina/efeitos dos fármacos , Resistência a Vancomicina/genética , Enterococos Resistentes à Vancomicina/efeitos dos fármacos , Enterococos Resistentes à Vancomicina/patogenicidade
10.
APMIS ; 127(11): 717-726, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31407405

RESUMO

This study aims to determine the prevalence of Staphylococcus aureus colonizing patients and ICU environment of a teaching hospital, the virulence and antimicrobial susceptibility profile of the isolates, and to evaluate the genetic relationship among them. A total of 536 swabs (134 of patients and 402 of ICU environment) were collected and analyzed to detect S. aureus. The antimicrobial susceptibility of the isolates was determined by disk diffusion test, and the detection of the mecA and virulence factors genes was performed by PCR, in addition to SCCmec typing. The genetic similarity of the isolates was determined by PFGE. Staphylococcus aureus was isolated in 12.7% of the swabs. The prevalence of colonization was 13.4% in patients and 12.4% in the environmental samples. The multidrug resistance was determined in 82.4% of the isolates. The prevalence of methicillin-resistant S. aureus was 20.6%, with 50.0% classified as SCCmec IV. The intermediate resistance to vancomycin was detected in 5.9% and 4.4% of the isolates obtained from patients and environment, respectively. Identical isolates obtained from different patients and sources were grouped into several clusters. The results showed dissemination of multidrug-resistant strains between patients and fomites and the persistence of MRSA and VISA isolates in the ICU environment.


Assuntos
Antibacterianos/farmacologia , Resistência a Meticilina , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/patogenicidade , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/genética , Staphylococcus aureus/patogenicidade , Proteínas de Bactérias/genética , Farmacorresistência Bacteriana , Feminino , Variação Genética , Humanos , Unidades de Terapia Intensiva/estatística & dados numéricos , Masculino , Meticilina/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Filogenia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Vancomicina/farmacologia , Virulência , Fatores de Virulência/genética
11.
BMC Infect Dis ; 19(1): 620, 2019 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-31299909

RESUMO

BACKGROUND: Escherichia coli lineage ST131 predominates across various spectra of extra-intestinal infections, including urinary tract infection (UTI). The distinctive resistance profile, diverse armamentarium of virulence factors and rapid global dissemination of ST131 E. coli makes it an intriguing pathogen. However, not much is known about the prevalence and genetic attributes of ST131 lineage in Pakistan. METHODS: We estimated prevalence and genetic attributes of E. coli ST131 isolates causing UTI among 155 randomly selected samples. Samples were analyzed for phylogenetic grouping, O-typing and fumC/fimH typing. Isolates were further tested for the ESBL and virulence factors using PCR. RESULTS: Overall, 59% of the UPEC isolates belonged to the phylogenetic group B2, followed by D = 28%, B1 = 8% and A = 5%. Among 18 different Sequence-types, ST131 was the dominant lineage (n = 71; 46%) out of which 72% of the isolates were assigned to the phylogenetic group B2, while 61% adhered to the serogroup O25b. FumC/fimH typing confirmed 49% of the ST131 as H30 sub-types. In this study, significant numbers of the identified ST131 isolates were MDR and 42% showed ESBL phenotypes, out of which 37% carried bla-CTX-M-15. Moreover, different virulence factors were detected in following percentages: fimH,155(100%), iutA 86 (55%), feoB 76 (49%), papC 75 (48%), papGII 70 (45%), kpsMTII 40 (26%), papEF 37 (24%), fyuA 37 (24%), usp 22 (14%), papA 20 (13%), sfa/foc20 (13%), hlyA 18 (12%), afa 15 (10%), cdtB 11 (7%), papGI 6 (4%), papGIII 6 (4%), kpsMTIII 4 (3%) and bmaE2 (1%). CONCLUSION: Conclusively, this study provides important insight into the genetic and virulence attributes of pandemic MDR ST131 strains involved in UTIs. It also highlights higher prevalence of ST131-O25b-H30 UPEC isolates in patients, which was previously unreported from this part of globe.


Assuntos
Infecções por Escherichia coli/microbiologia , Infecções Urinárias/diagnóstico , Escherichia coli Uropatogênica/classificação , Farmacorresistência Bacteriana Múltipla/genética , Infecções por Escherichia coli/diagnóstico , Infecções por Escherichia coli/epidemiologia , Feminino , Humanos , Masculino , Paquistão/epidemiologia , Filogenia , Prevalência , Infecções Urinárias/epidemiologia , Infecções Urinárias/microbiologia , Escherichia coli Uropatogênica/isolamento & purificação , Escherichia coli Uropatogênica/patogenicidade , Virulência , Fatores de Virulência/classificação , Fatores de Virulência/genética , beta-Lactamases/classificação , beta-Lactamases/genética
12.
J Med Microbiol ; 68(9): 1330-1340, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31347999

RESUMO

Purpose. This study aimed to characterize 27 Escherichia coli isolates obtained from peritoneal dialysis (PD)-related peritonitis that occurred at the University Hospital of Botucatu Medical School, Brazil, between 1997 and 2015.Methodology. These isolates were characterized regarding the occurrence of 22 virulence factor-encoding genes, antimicrobial resistance and biofilm production. We then evaluated whether these factors influenced the clinical outcome.Results. Over an 18-year period, 726 episodes of PD-related peritonitis were diagnosed, with 27 of them (3.7 %) being due to E. coli. The majority of the isolates were classified in phylogroups B1 (33.3 %), B2 (30.0 %) or F (18.0 %). fimH (100.0 %), ompT (66.7 %) and irp2 (51.9 %) were the most prevalent genes, while papA, papC, iha, sat, irp2, iucD, ireA, ibe10, ompT and kpsMTII were significantly more prevalent among isolates belonging to phylogroups B2 and F (P<0.05). Non-susceptibility to quinolones was detected in six isolates, which harboured chromosomal and/or plasmid-mediated quinolone resistance determinants, while two CTX-M extended-spectrum ß-lactamase-producing E. coli were identified. Virulence factor-encoding genes (alone or in combination) and antimicrobial resistance were not associated with non-resolution outcomes. However, there was a trend for the ability to produce biofilm to be associated with treatment failure, although this association was not statistically significant.Conclusion. The E. coli isolates were heterogeneous in terms of the features investigated, and were susceptible to most of the antimicrobial drugs tested, despite the unsuccessful treatment observed in more than 50.0 % of the patients. Studies including more cases could help to clarify if biofilm production can influence the outcome in patients with PD-related peritonitis.


Assuntos
Infecções por Escherichia coli/microbiologia , Escherichia coli/isolamento & purificação , Diálise Peritoneal/efeitos adversos , Peritonite/microbiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/farmacologia , Biofilmes/crescimento & desenvolvimento , Variação Biológica da População , Brasil/epidemiologia , Criança , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Escherichia coli/patogenicidade , Infecções por Escherichia coli/epidemiologia , Variação Genética , Técnicas de Genotipagem , Hospitais Universitários , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Peritonite/epidemiologia , Filogenia , Plasmídeos/análise , Fatores de Virulência/genética , Adulto Jovem
13.
Vet Microbiol ; 235: 43-52, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31282378

RESUMO

Even though it is widely known that Cryptococcus spp. may transmit cryptococcosis trough aerosol formed when dried birds (mainly pigeons) droppings are dispersed and become airborne, little is known about the role of these birds in harboring other pathogenic yeasts in their gastrointestinal tract, feathers and beaks, specifically because these animals often stay and reproduce close or even above air conditioner units. Here we evaluated the prevalence of pathogenic yeasts isolated from pigeon droppings collected in the outside area of a University Hospital in Brazil. We also aimed to investigate the pathogenic potential and antifungal susceptibility of Candida species of medical interest isolated from these samples. Therefore, we performed the evaluation of virulence factors attributes expression in vitro, including the ability to adhere to human buccal epithelial cells and biofilm formation and to produce lytic enzymes, such as phospholipases, proteinases and hemolysins. Antifungal susceptibility testing against fluconazole, itraconazole, amphotericin and micafungin was also performed. The Candida genus was the most prevalent in our study, with several medically important species being isolated. Of note, these strains were able to express several virulence factors in vitro, clearly showing their pathogenic potential. Our study was able to demonstrate that Candida spp. isolated from pigeon droppings may express virulence factors in the same manner of clinical isolates, suggesting a pathogenic potential for these yeasts. The fact these strains were collected from the outside area of a tertiary hospital may be of interest, because they may be a source of infection, specifically to immunocompromised hosts.


Assuntos
Antifúngicos/farmacologia , Azóis/farmacologia , Candida/efeitos dos fármacos , Columbidae/microbiologia , Farmacorresistência Fúngica , Fatores de Virulência/genética , Anfotericina B/farmacologia , Animais , Brasil , Candida/genética , Candida/isolamento & purificação , Criptococose/veterinária , Fezes/microbiologia , Fluconazol/farmacologia , Itraconazol/farmacologia , Testes de Sensibilidade Microbiana
14.
Vet Microbiol ; 235: 93-100, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31282384

RESUMO

Staphylococcus aureus biofilm-related infections are of clinical concern due to the capability of bacterial colonies to adapt to a hostile environment. The present study investigated the capability of the acute phase protein alpha 1-acid glycoprotein (AGP) to a) disrupt already established S. aureus biofilm and b) interfere with the biofilm de novo production by using Microtiter Plate assay (MtP) on field strains isolated from infected quarters by assessing. The present study also investigated whether AGP could interfere with the expression of bacterial genes related to biofilm formation (icaA, icaD, icaB, and icaC) and adhesive virulence determinants (fnbA, fnbB, clfA, clfB, fib, ebps, eno) by quantitative real-time PCR (qPCR). The results provided the evidence that AGP could disrupt the biofilm structure only when it was already developed, but could not prevent the de novo biofilm formation. Moreover, AGP could interfere with the expression levels of genes involved in biofilm formation in a dose- and strain-dependent way, by upregulating, or downregulating, icaABC genes and fnbB, respectively. The results presented in this study provide new insights about the direct antibacterial activity of AGP in bovine milk. It remains to be demonstrated the molecular bases of AGP mechanism of action, in particular for what concerns the scarce capability to interact with the de novo formation of biofilm.


Assuntos
Biofilmes , Orosomucoide/metabolismo , Infecções Estafilocócicas/veterinária , Staphylococcus aureus/patogenicidade , Animais , Bovinos , Feminino , Genes Bacterianos , Genótipo , Leite/química , Staphylococcus aureus/genética , Fatores de Virulência/genética
15.
Nat Commun ; 10(1): 2931, 2019 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-31270321

RESUMO

The virulence of Pseudomonas aeruginosa, a Gram-negative opportunistic pathogen, is regulated by many transcriptional factors (TFs) that control the expression of quorum sensing and protein secretion systems. Here, we report a genome-wide, network-based approach to dissect the crosstalk between 20 key virulence-related TFs. Using chromatin immunoprecipitation coupled with high-throughput sequencing (ChIP-seq), as well as RNA-seq, we identify 1200 TF-bound genes and 4775 differentially expressed genes. We experimentally validate 347 of these genes as functional target genes, and describe the regulatory relationships of the 20 TFs with their targets in a network that we call 'Pseudomonas aeruginosa genomic regulatory network' (PAGnet). Analysis of the network led to the identification of novel functions for two TFs (ExsA and GacA) in quorum sensing and nitrogen metabolism. Furthermore, we present an online platform and R package based on PAGnet to facilitate updating and user-customised analyses.


Assuntos
Proteínas de Bactérias/genética , Pseudomonas aeruginosa/genética , Fatores de Transcrição/genética , Proteínas de Bactérias/metabolismo , Imunoprecipitação da Cromatina , Regulação Bacteriana da Expressão Gênica , Genoma Bacteriano , Genômica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/metabolismo , Pseudomonas aeruginosa/patogenicidade , Fatores de Transcrição/metabolismo , Virulência , Fatores de Virulência/genética , Fatores de Virulência/metabolismo
16.
Rev Inst Med Trop Sao Paulo ; 61: e36, 2019 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-31340248

RESUMO

During the last years, Brazilian government control programs have detected an increase of Salmonella Heidelberg in poultry slaughterhouses a condition that poses a threat to human health However, the reasons remain unclear. Differences in genetic virulence profiles may be a possible justification. In addition, effective control of Salmonella is related to an efficient epidemiological surveillance system through genotyping techniques. In this context, the aim of this study was the detection of 24 virulence-associated genes in 126 S. Heidelberg isolates. We classified the isolates into 56 different genetic profiles. None of the isolates presented all the virulence genes. The prevalence of these genes was high in all tested samples as the lowest number of genes detected in one isolate was 10/24. The lpfA and csgA (fimbriae), invA and sivH (TTSS), and msgA and tolC (intracellular survival) genes were present in 100% of the isolates analyzed. Genes encoding effector proteins were detected in the majority of SH isolates. No single isolate had the sefA gene. The pefA gene was found in only four isolates. We have also performed a screening of genes associated with iron metabolism: 88.9% of isolates had the iroN geneand 79.4% the sitC gene . Although all the isolates belong to the same serotype, several genotypic profiles were observed. These findings suggest that there is a diversity of S. Heidelberg isolates in poultry products. The fact that a single predominant profile was not found in this study indicates the presence of variable sources of contamination caused by SH. The detection of genetic profiles of Salmonella strains can be used to determine the virulence patterns of SH isolates.


Assuntos
Doenças das Aves Domésticas/microbiologia , Produtos Avícolas/microbiologia , Salmonelose Animal/microbiologia , Salmonella/genética , Salmonella/patogenicidade , Fatores de Virulência/genética , Virulência/genética , Animais , Microbiologia de Alimentos , Genótipo , Reação em Cadeia da Polimerase
17.
Rev Soc Bras Med Trop ; 52: e20180285, 2019 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-31340355

RESUMO

INTRODUCTION: Salmonella enterica serovar Panama belongs to the D1 serogroup and is frequently associated with nontyphoidal salmonellosis in humans. This study aimed to characterize isolates collected from Northeast Brazil by phenotypic and molecular methods. METHODS: Forty four S. Panama strains were examined for antimicrobial susceptibility, virulence genes, and pulsed field gel electrophoresis (PFGE) types. RESULTS: All strains were susceptible to antibiotics (except for streptomycin), presented classical virulence factors, and could be clustered into four groups and 18 pulsotypes. CONCLUSIONS: This work calls for continuous surveillance for the emergence of antibiotic resistance and new clones in a geographical area.


Assuntos
Salmonella enterica/genética , Fatores de Virulência/genética , Animais , Antibacterianos/farmacologia , Brasil , Farmacorresistência Bacteriana Múltipla , Eletroforese em Gel de Campo Pulsado , Variação Genética , Humanos , Testes de Sensibilidade Microbiana , Salmonella enterica/efeitos dos fármacos , Salmonella enterica/isolamento & purificação , Salmonella enterica/patogenicidade
18.
Sci Total Environ ; 690: 313-320, 2019 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-31299566

RESUMO

The Gram-negative bacterium Aeromonas salmonicida subsp. salmonicida is an aquatic pathogen which causes furunculosis to salmonids, especially in fish farms. The emergence of strains of this bacterium exhibiting antibiotic resistance is increasing, limiting the effectiveness of antibiotherapy as a treatment against this worldwide disease. In the present study, we discovered an isolate of A. salmonicida subsp. salmonicida that harbors two novel plasmids variants carrying antibiotic resistance genes. The use of long-read sequencing (PacBio) allowed us to fully characterize those variants, named pAsa5-3432 and pRAS3-3432, which both differ from their classic counterpart through their content in mobile genetic elements. The plasmid pAsa5-3432 carries a new multidrug region composed of multiple mobile genetic elements, including a Class 1 integron similar to an integrated element of Salmonella enterica. With this new region, probably acquired through plasmid recombination, pAsa5-3432 is the first reported plasmid of this bacterium that bears both an essential virulence factor (the type three secretion system) and multiple antibiotic resistance genes. As for pRAS3-3432, compared to the classic pRAS3, it carries a new mobile element that has only been identified in Chlamydia suis. Hence, with the identification of those two novel plasmids harboring mobile genetic elements that are normally encountered in other bacterial species, the present study puts emphasis on the important impact of mobile genetic elements in the genomic plasticity of A. salmonicida subsp. salmonicida and suggests that this aquatic bacterium could be an important reservoir of antibiotic resistance genes that can be exchanged with other bacteria, including human and animal pathogens.


Assuntos
Aeromonas salmonicida/genética , Resistência Microbiana a Medicamentos/genética , Animais , Genes Bacterianos , Genoma Bacteriano , Suínos , Fatores de Virulência/genética
19.
Int J Food Microbiol ; 306: 108269, 2019 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-31330452

RESUMO

Salmonella enterica serovar Enteritidis strain SE86 has been associated with several foodborne diseases occurring in Southern Brazil, becoming and important causative agent of human salmonellosis. In this work, the complete genome of the bacterium Salmonella Enteritidis SE86 was sequenced using the Illumina MiSeq platform. An in silico analysis of the SE86 genome was performed in order to compare it with different Salmonella strains as well as to investigate the presence of stress-resistance and virulence genes. This strain showed a variety of genes that can be involved in antimicrobial and biocide resistance, acid and thermal resistance as well as virulence and adhesion. These genetic features could explain its increased resistance and the prevalence of this strain in foodborne outbreaks in Southern Brazil.


Assuntos
Antibacterianos/farmacologia , Intoxicação Alimentar por Salmonella/epidemiologia , Salmonella enteritidis , Brasil/epidemiologia , Surtos de Doenças , Genoma Bacteriano/genética , Humanos , Testes de Sensibilidade Microbiana , Intoxicação Alimentar por Salmonella/microbiologia , Salmonella enteritidis/efeitos dos fármacos , Salmonella enteritidis/genética , Salmonella enteritidis/patogenicidade , Virulência/genética , Fatores de Virulência/genética
20.
Rev Soc Bras Med Trop ; 52: e20190095, 2019 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-31340369

RESUMO

INTRODUCTION: Staphylococcus aureus is a major nosocomial pathogen that is associated with high virulence and the rapid development of drug resistance. METHODS: We analyzed and compared the antimicrobial resistance, virulence profiles, and molecular epidemiology of 67 S. aureus strains, including 36 methicillin-sensitive (MSSA) and 31 methicillin-resistant (MRSA) strains recovered from a public hospital located in south-eastern Brazil. RESULTS: The clones circulating in this hospital presented a great diversity, and the majority of the strains were related to clones responsible for causing worldwide epidemics: these included USA100 (New York/Japan clone), USA300, and USA600. The 31 MRSA (22 SCCmecII and 9 SCCmecIV) and 36 MSSA strains exhibited low resistance against gentamicin and trimethoprim/sulfamethoxazole. No MRSA strain showed resistance to tetracycline. Virulence gene carriage was more diverse and abundant in MSSA than in MRSA. Of the evaluated adhesion-related genes, ebpS was the most prevalent in both MSSA and MRSA strains. The genes bbp and cna showed a strong association with MSSA strains. CONCLUSIONS: Our findings reinforce the idea that MSSA and MRSA strains should be carefully monitored, owing to their high pathogenic potential.


Assuntos
Antibacterianos/farmacologia , Resistência a Meticilina , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/genética , Fatores de Virulência/genética , Brasil/epidemiologia , Hospitais Públicos , Humanos , Testes de Sensibilidade Microbiana , Epidemiologia Molecular , Infecções Estafilocócicas/epidemiologia , Staphylococcus aureus/classificação , Staphylococcus aureus/isolamento & purificação , Centros de Atenção Terciária , Virulência/genética
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