RESUMO

Consumption of raw, undercooked or contaminated animal food products is a frequent cause of Campylobacter jejuni infection. Brazil is the world's third largest producer and a major exporter of chicken meat, yet population-level genomic investigations of C. jejuni in the country remain scarce. Analysis of 221 C. jejuni genomes from Brazil shows that the overall core and accessory genomic features of C. jejuni are influenced by the identity of the human or animal source. Of the 60 sequence types detected, ST353 is the most prevalent and consists of samples from chicken and human sources. Notably, we identified the presence of diverse bla genes from the OXA-61 and OXA-184 families that confer beta-lactam resistance as well as the operon cmeABCR related to multidrug efflux pump, which contributes to resistance against tetracyclines, macrolides and quinolones. Based on limited data, we estimated the most recent common ancestor of ST353 to the late 1500s, coinciding with the time the Portuguese first arrived in Brazil and introduced domesticated chickens into the country. We identified at least two instances of ancestral chicken-to-human infections in ST353. The evolution of C. jejuni in Brazil was driven by the confluence of clinically relevant genetic elements, multi-host adaptation and clonal population growth that coincided with major socio-economic changes in poultry farming.

Assuntos

RESUMO

Salmonella Enteritidis, Escherichia coli, and Campylobacter jejuni are among the most common foodborne pathogens worldwide, and poultry products are strongly associated with foodborne pathogen outbreaks. These pathogens are capable of producing biofilms on several surfaces used in the food processing industry, including polyethylene and stainless steel. However, studies on multi-species biofilms are rare. Therefore, this study aimed to develop predictive mathematical models to simulate the adhesion and removal of multispecies biofilms. All combinations of microorganisms resulted in biofilm formation with differences in bacterial counts. E. coli showed the greatest ability to adhere to both surfaces, followed by S. Enteritidis and C. jejuni. The incubation time and temperature did not influence adhesion. Biofilm removal was effective with citric acid and benzalkonium chloride but not with rhamnolipid. Among the generated models, 46 presented a significant coefficient of determination (R2), with the highest R2 being 0.88. These results provide support for the poultry industry in creating biofilm control and eradication programs to avoid the risk of contamination of poultry meat.

RESUMO

Campylobacteriosis is currently recognized as one of the major causes of foodborne bacterial diseases worldwide. In Brazil, there is insufficient data to estimate the impact of Campylobacter in public health. The aim of this present study was to characterize a C. jejuni CJ-HBSJRP strain isolated from a hospitalized patient in Brazil by its ability to invade human Caco-2 epithelial cells, to survive in U937 human macrophages, and to assess its phenotypic antimicrobial resistance profile. In addition, prophages, virulence and antimicrobial resistance genes were search using whole-genome sequencing data. The genetic relatedness was evaluated by MLST and cgMLST analysis by comparison with 29 other C. jejuni genomes isolated from several countries. The CJ-HBSJRP strain showed an invasion percentage of 50% in Caco-2 polarized cells, 37.5% of survivability in U937 cells and was phenotypically resistant to ampicillin, ciprofloxacin and nalidixic acid. A total of 94 virulence genes related to adherence, biofilm, chemotaxis, immune modulation, invasion process, metabolism, motility and toxin were detected. The resistance genes blaOXA-605 (blaOXA-61), cmeB and mutations in the QRDR region of gyrA were also found and none prophages were detected. The MLST analysis showed 23 different STs among the strains studied. Regarding cgMLST analysis, the CJ-HBSJRP strain was genetically distinct and did not group closely to any other isolate. The results obtained reinforce the pathogenic potential of the CJHBSJRP strain and highlighted the need for more careful attention to Campylobacter spp. infections in Brazil since this pathogen has been the most commonly reported zoonosis in several countries worldwide.

Assuntos

RESUMO

Campylobacter is one of the most common causes of foodborne gastroenteritis. The objective of this study was to estimate the prevalence and risk factors associated with Campylobacter jejuni and Campylobacter coli species in fresh chicken carcasses for human consumption from farmers' markets and small food stores in seven localities of Bogotá, Colombia. Ninety-one samples of fresh chicken carcasses were collected from farmers' markets and small food stores at seven localities in Bogotá. Samples were tested for Campylobacter using the real-time polymerase chain reaction (real time PCR) and isolation by plating. To analyze possible risk factors associated with Campylobacter spp. contamination in retail chicken carcasses, information was collected using a structured questionnaire and a univariate logistic regression analysis (α = 0.05) was used. Forty-two positive samples were obtained for Campylobacter spp., given a prevalence of 46.2%, of which 54.8% were to C. jejuni, 9.52% to C. coli and 35.7% to joint contaminations. C. jejuni was the most prevalent species. Risk factors found included poor cleanliness, in frequency of disinfection, type of establishment, and direct contact of chickens with other food. This study is the first report in the country on the prevalence and risk factors of Campylobacter in retail chicken.

RESUMO

El síndrome de Guillain Barré es una enfermedad derivada del compromiso en las neuronas del sistema nervioso periférico por una respuesta descontrolada del sistema inmune que conduce daño axonal y/o desmielinización. El objetivo de este reporte fue describir los 10 primeros casos sospechosos de Síndrome de Guillain Barré en Piura. Se logró identificar la presencia de Campylobacter jejuni en las muestras de heces del 80% de los pacientes reportados. Es muy importante reconocer rápida y oportunamente al paciente con diagnóstico sospechoso de Guillain Barré, y realizar los estudios necesarios en un brote para identificar los agentes desencadenantes del cuadro.

Guillain Barré syndrome is a disease derived from compromise in neurons of the peripheral nervous system by an uncontrolled response from the immune system that leads to axonal damage and/or demyelination. The objective of this report was to describe the first 10 suspected cases of Guillain Barre Syndrome in Piura. It was possible to identify the presence of Campylobacter jejuni in the stool samples of 80% of the reported patients. It is very important to quickly and opportunely recognize the patient with a suspected diagnosis of Guillain Barré, and to carry out the necessary studies in an outbreak to identify the triggering agents of the condition.

RESUMO

This work describes the preparation, characterization and antimicrobial activity of four palladium(II) complexes, namely, [Pd(meg)(1,10-phen)] 1, [Pd(meg)(PPh3)2] 2, [Pd(og)(1,10-phen)] 3 and [Pd(og)(PPh3)2] 4, where meg = methyl gallate, og = octyl gallate, 1,10-phen = 1,10-phenanthroline and PPh3 = triphenylphosphine. As to the chemical structures, spectral and physicochemical studies of 1-4 indicated that methyl or octyl gallate coordinates a palladium(II) ion through two oxygen atoms upon deprotonation. A chelating bidentate phenanthroline or two triphenylphosphine molecules complete the coordination sphere of palladium(II) ion, depending on the complex. The metal complexes were tested against the Mycobacterium tuberculosis H37Rv strain and 2 exhibited high activity (MIC = 3.28 µg/mL). As to the tests with Campylobacter jejuni, complex 1 showed a significant effect in reducing bacterial population (greater than 7 log CFU) in planktonic forms, as well as in the biomass intensity (IBF: 0.87) when compared to peracetic acid (IBF: 1.11) at a concentration of 400 µg/mL. The effect provided by these complexes has specificity according to the target microorganism and represent a promising alternative for the control of microorganisms of public health importance.

Assuntos

RESUMO

In this study a data dependent acquisition label-free based proteomics approach was used to identify pH-dependent proteins that respond in a growth phase independent manner in Campylobacter jejuni reference strain NCTC 11168. NCTC 11168 was grown within its pH physiological normal growth range (pH 5.8, 7.0 and 8.0, µ = âˆ¼0.5 h-1) and exposed to pH 4.0 shock for 2 h. It was discovered that gluconate 2-dehydrogenase GdhAB, NssR-regulated globins Cgb and Ctb, cupin domain protein Cj0761, cytochrome c protein CccC (Cj0037c), and phosphate-binding transporter protein PstB all show acidic pH dependent abundance increases but are not activated by sub-lethal acid shock. Glutamate synthase (GLtBD) and the MfrABC and NapAGL respiratory complexes were induced in cells grown at pH 8.0. The response to pH stress by C. jejuni is to bolster microaerobic respiration and at pH 8.0 this is assisted by accumulation of glutamate the conversion of which could bolster fumarate respiration. The pH dependent proteins linked to growth in C. jejuni NCTC 11168 aids cellular energy conservation maximising growth rate and thus competitiveness and fitness.

Assuntos

RESUMO

This work describes the synthesis and characterization of two metal complexes of the type [M(L1)2(phen)], where M = Pt2+ (complex I) or Pd2+ (complex II), L1 = 5-amino-1,3,4-thiadiazole-2(3H)-thiolate and phen = 1,10-phenanthroline. The in vitro antibacterial activity of these complexes was investigated in isolation and synergistically with ciprofloxacin (CIP) and erythromycin (ERY) in three strains of Campylobacter jejuni (MIC = 32 mg/L for CIP and ERY), selected from a bank of 235 strains representative of three poultry exporting states of the country (A, B and C), previously analyzed for epidemiology and resistance to CIP and ERY. A total of 53/235 (22.55%) strains showed co-resistance to CIP and ERY. Isolated resistance to CIP was higher than to ERY. Epidemiological analysis showed that resistance to CIP was more evident in state B (p < 0.0001), as well as a higher susceptibility to ERY in state C (p = 0.0028). Co-resistance was expressive in state A and in the spring and fall seasons. The evaluation of I alone and in synergy with CIP and ERY found values up to 0.25 mg/L not significant for ERY. Complex II did not show an antimicrobial effect on the three strains of tested C. jejuni. The effect provided by complex I represents a promising alternative for control of resistant strains of C. jejuni.

RESUMO

INTRODUCTION: Campylobacter jejuni is one of the most common bacterial causes of human gastroenteritis. Despite its public health importance, the virulence factors and mechanisms underlying C. jejuni pathogenesis remain poorly understood and the relationships between these genes and the sources of the strains are not clear. We aimed to determine the virulence profiles of C. jejuni isolated from poultry and human cases of Campylobacteriosis. METHODOLOGY: A total of 50 strains of C. jejuni isolated from poultry and human cases of Campylobacteriosis were screened by polymerase chain reaction (PCR) for the presence of six pathogenic genes (flaA, iam, wlaN, cdtA, cdtB, cdtC). RESULTS: A total of 40% (10/25) of the human isolates presented only one virulence marker. In contrast, 64% (16/25) of the poultry-derived strains showed four or five virulence markers. cdtA and flaA occurred more frequently in poultry-derived strains than in human strains. Ten different virulence profiles were observed among the human isolates and 11 among the poultry strains. Only four profiles were common to both sources: profiles 3 (flaA, cdtA, cdtB, and cdtC), 5 (cdtA and cdtB), 7 (flaA and cdtB), and 10 (iam, flaA, cdtA, cdtB, and cdtC). The human-derived strains had a higher Shannon diversity index (1.9396) and Simpson index (0.8367), indicating a more diversified population than found in poultry (1.7742 and 0.7333, respectively). CONCLUSIONS: We found variations in the genetic profiles of the circulating strains based on the isolation source and genes that are potentially pathogenic to humans were detected in poultry-derived strains.

Assuntos

RESUMO

Campylobacter jejuni infection is considered the most frequent factor associated with Guillain-Barré syndrome (GBS). In 2019, a large outbreak of GBS was detected in Peru, being associated with C. jejuni detected in stool samples from these patients. The aim of this study was to determine the molecular epidemiology of C. jejuni strains (ST-2993) associated with a large GBS outbreak in Peru. In this study, 26 C. jejuni strains belonging to the ST-2293, obtained from 2019 to 2020, were sequenced using Illumina technology. Five low-quality sequences were removed using bioinformatics, and 21 genomes (17 clinical strains and 4 chicken strains) were considered in the phylogenetic analysis and comparative genomics. Phylogenetic reconstruction, including genomes from international databases, showed a connection between Peruvian and Chinese GBS strains, both of them having lipooligosaccharides (LOS) locus genes related to molecular mimicry with gangliosides in peripheral nerves. Also, ST-2993 was detected in Amazon strains recovered many years before the 2019 outbreak, but with no epidemiological connection with GBS. Besides, a close relationship between human and chicken C. jejuni strains indicated chicken as one of the probable reservoirs. Finally, comparative genomics revealed differences between Chinese and Peruvian strains, including the presence of a prophage inserted into the genome. In conclusion, C. jejuni ST-2993 strains recovered from the GBS outbreak are closely related to Peruvian Amazon strains. Moreover, ST-2993 has been circulated in Peru since 2003 in the Peruvian Amazonia, showing the necessity to reinforce the epidemiological surveillance of C. jejuni to improve the prevention and control of future GBS outbreaks. IMPORTANCE This article describes the molecular epidemiology of C. jejuni strains (ST-2993) associated with a large Guillain-Barré Syndrome (GBS) outbreak in Peru, sequencing several strains recovered from GBS patients and chickens from 2019 to 2020. Phylogenetic analysis showed a connection between Peruvian and Chinese GBS strains, both of them having lipooligosaccharides (LOS) locus genes related to molecular mimicry with gangliosides in peripheral nerves. Also, ST-2993 strains were detected in isolates recovered many years before the 2019 outbreak, but with no epidemiological connection with GBS. Besides, a close relationship between human and chicken strains indicated those animals as a probable reservoir. This information will help to understand the real situation of GBS in Peru and its causal agent, C. jejuni ST-2993, showing the necessity to increase epidemiological tracking of these kinds of pathogens to detect them and avoid GBS outbreaks in the future.

Assuntos