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1.
Braz J Microbiol ; 52(2): 859-867, 2021 Jun.
Article in English | MEDLINE | ID: mdl-33590448

ABSTRACT

Campylobacter spp. have been a predominant cause of bacterial foodborne gastroenteritis worldwide, causing substantial costs to public healthcare systems. This study aimed to assess the invasion and pro-inflammatory cytokine production capacity of Campylobacter coli strains isolated in Brazil. A total of 50 C. coli isolated from different sources in Brazil were analyzed for their capacity of invasion in Caco-2 and U-937 cell lines. The production of pro-inflammatory cytokines was quantitatively measured in response to C. coli. All the strains studied showed invasion percentage ≥ 40% in polarized Caco-2 cells. In U-937 cells assay, 35 of 50 C. coli strains studied showed invasion percentage ≥ 50%. A significant increase in IL-8 production by infected U-937 cells was observed for 17.5% of the C. coli isolates. The high percentages of invasion in Caco-2 and U-937 cells observed for all studied strains, plus the increased production of IL-8 by U-937 cells against some strains, highlighted the pathogenic potential of the C. coli studied and bring extremely relevant data since it has never been reported for strains isolated in Brazil and there are a few data for C. coli in the literature.


Subject(s)
Campylobacter coli/physiology , Epithelial Cells/microbiology , Interleukin-8/metabolism , Phagocytes/microbiology , Brazil , Caco-2 Cells , Campylobacter coli/isolation & purification , Cytokines/metabolism , Epithelial Cells/metabolism , Humans , Phagocytes/metabolism , U937 Cells
2.
Microb Drug Resist ; 26(12): 1466-1471, 2020 Dec.
Article in English | MEDLINE | ID: mdl-32311302

ABSTRACT

Whole-genome sequencing analyses have provided important data and information on the repertoire of resistance genes in several bacterial species. This study examined to what extent the antimicrobial resistance genes found in a set of whole-genome-sequenced Salmonella Enteritidis strains from Brazil correlated with the phenotypic antimicrobial resistance possibly related to these genes. The genotypic resistance data from the strains studied were compared with publicly available data from strains isolated in other countries. The genotypic resistance profiles were accessed on the NCBI Pathogen Detection website, and the phenotypic resistance profiles were determined by the disk diffusion technique according to the Clinical and Laboratory Standards Institute guidelines. Fourteen of the 256 sequenced strains presented antimicrobial resistance genes, with the highest prevalence of resistance genes to aminoglycosides-with 16 genes detected in seven strains-not only in Brazilian strains but also in the strains from other parts of the world. The strongest correlation between phenotypic and genotypic resistance was found for tetracycline (75%). The genotypic and phenotypic profiles of the S. Enteritidis strains studied only partially matched, and they diverged in some antimicrobial classes more strongly than in other classes. The advances on whole-genome sequencing analyses associated with a better understanding of the correlation between phenotypic and genotypic resistance data may improve this powerful tool for antimicrobial resistance prediction.


Subject(s)
Anti-Bacterial Agents/pharmacology , Drug Resistance, Multiple, Bacterial/genetics , Salmonella enterica/genetics , Salmonella enteritidis/genetics , Brazil , Drug Resistance, Multiple, Bacterial/drug effects , Genotype , Microbial Sensitivity Tests , Phenotype , Salmonella enterica/drug effects , Salmonella enteritidis/drug effects , Whole Genome Sequencing
3.
Microb Drug Resist ; 26(12): 1516-1525, 2020 Dec.
Article in English | MEDLINE | ID: mdl-31794692

ABSTRACT

Aims: The objectives of this study were to genotype a total of 48 Campylobacter jejuni and 39 Campylobacter coli strains isolated in Brazil from 1995 to 2016 by multilocus sequence typing (MLST) and to determine their resistance profile. The presence or points of mutation in the related resistance genes was verified. Results: By MLST, C. jejuni strains were typed into 36 STs and C. coli strains were typed into 27 STs. A total of 70.8% of C. jejuni and 35.9% of C. coli were resistant to at least one antimicrobial tested. The tet(O) gene was detected in 43.7% C. jejuni and in 12.8% C. coli. The ermB gene was not detected and one C. jejuni presented the mutation in the 23S rRNA gene. Besides, 58.3% C. jejuni presented the substitution T86I in the quinolone resistance-determining region of gyrA and 15.4% C. coli presented the substitution T38I. The cmeB gene was detected in 97.9% C. jejuni and in 97.4% C. coli. Conclusion: The presence of C. jejuni and C. coli resistant to some antimicrobial agents of clinical use is of public health concern. The presence of STs shared between Brazilian strains and isolates of different countries is of concern since it might suggest a possible spread of these shared types.


Subject(s)
Anti-Bacterial Agents/pharmacology , Campylobacter coli/genetics , Campylobacter jejuni/genetics , Drug Resistance, Bacterial/genetics , Animals , Brazil , Campylobacter coli/drug effects , Campylobacter jejuni/drug effects , Chickens/microbiology , Food Microbiology , Genes, Bacterial , Genotype , Haplorhini/microbiology , Humans , Monkey Diseases/epidemiology , Multilocus Sequence Typing , Poultry Diseases/epidemiology , Sewage/microbiology , Water Microbiology
4.
Food Microbiol ; 73: 327-333, 2018 Aug.
Article in English | MEDLINE | ID: mdl-29526220

ABSTRACT

Campylobacter spp. have been the most commonly reported gastrointestinal bacterial pathogen in many countries. Consumption of improperly prepared poultry meat has been the main transmission route of Campylobacter spp. Although Brazil is the largest exporter of poultry meat in the world, campylobacteriosis has been a neglected disease in the country. The aim of this study was to characterize 50 Campylobacter coli strains isolated from different sources in Brazil regarding the frequency of 16 virulence genes and their survival capability under five different stress conditions. All strains studied presented the cadF, flaA, and sodB genes that are considered essential for colonization. All strains grew at 4 °C and 37 °C after 24 h. High survival rates were observed when the strains were incubated in BHI with 7.5% NaCl and exposed to acid and oxidative stress. In conclusion, the pathogenic potential of the strains studied was reinforced by the presence of several important virulence genes and by the high growth and survival rates of the majority of those strains under different stress conditions. The results enabled a better understanding of strains circulating in Brazil and suggest that more rigorous control measures may be needed, given the importance of contaminated food as vehicles for Campylobacter coli.


Subject(s)
Campylobacter Infections/microbiology , Campylobacter Infections/veterinary , Campylobacter coli/growth & development , Poultry Diseases/microbiology , Animals , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Brazil , Campylobacter coli/classification , Campylobacter coli/genetics , Campylobacter coli/isolation & purification , Chickens , Food Safety , Humans , Meat/microbiology , Virulence Factors/genetics , Virulence Factors/metabolism
5.
J Med Microbiol ; 65(1): 80-90, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26531157

ABSTRACT

Campylobacter coli and Campylobacter jejuni are two of the most common causative agents of food-borne gastroenteritis in numerous countries worldwide. In Brazil, campylobacteriosis is under diagnosed and under-reported, and few studies have molecularly characterized Campylobacter spp. in this country. The current study genotyped 63 C. coli strains isolated from humans (n512), animals (n521), food (n510) and the environment (n520) between 1995 and 2011 in Brazil. The strains were genotyped using pulsed-field gel electrophoresis (PFGE), sequencing the short variable region (SVR) of the flaA gene ( flaA-SVR) and high-resolution melting analysis (HRMA) of the clustered regularly interspaced short palindromic repeat (CRISPR) locus to better understand C. coli genotypic diversity and compare the suitability of these three methods for genotyping this species. Additionally, the discrimination index (DI) of each of these methods was assessed. Some C. coli strains isolated from clinical and non-clinical origins presented ≥80 % genotypic similarity by PFGE and flaA-SVR sequencing. HRMA of the CRISPR locus revealed only four different melting profiles. In total, 22 different flaA-SVR alleles were detected. Of these, seven alleles, comprising gt1647­gt1653, were classified as novel. The most frequent genotypes were gt30 and gt1647. This distribution reveals the diversity of selected Brazilian isolates in comparison with the alleles described in the PubMLST database. The DIs for PFGE, flaA­SVR sequencing and CRISPR-HRMA were 0.986, 0.916 and 0.550, respectively. PFGE and flaA-SVR sequencing were suitable for subtyping C. coli strains, in contrast to CRISPR-HRMA. The high genomic similarity amongst some C. coli strains confirms the hypothesis that environmental and food sources potentially lead to human and animal contamination in Brazil.


Subject(s)
Bacterial Typing Techniques/methods , Campylobacter coli/classification , Genotyping Techniques/methods , Alleles , Animals , Brazil , Campylobacter Infections , Campylobacter coli/isolation & purification , DNA, Bacterial/genetics , Electrophoresis, Gel, Pulsed-Field , Environmental Microbiology , Flagellin/genetics , Food Contamination , Food Microbiology , Foodborne Diseases/microbiology , Genetic Loci , Humans , Sequence Analysis, DNA
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