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PloS One 2021Arcobacter butzleri is an emerging zoonotic food-borne and water-borne pathogen that can cause diarrhea in humans. The global prevalence of A. butzleri infection is...
Arcobacter butzleri is an emerging zoonotic food-borne and water-borne pathogen that can cause diarrhea in humans. The global prevalence of A. butzleri infection is underestimated, and little is known about their phenotypic and genotypic characterization. The aim of this study was to determine antimicrobial susceptibility (AST) profiles, detect related virulence genes, and classify sequence type (ST) of A. butzleri isolates obtained from human stool and food samples. A total of 84 A. butzleri isolates were obtained from human diarrheal (n = 25), non-diarrheal (n = 24) stool, and food (n = 35) samples in Thailand. They were evaluated for phenotypic identification by conventional microbiological procedures and AST by Kirby-Bauer disc diffusion method as well as virulence genes detection. Representative isolates from each origin were selected based on the presence of virulence genes and AST profiles to analyze genetic diversity by multilocus sequence typing (MLST). All isolates showed resistance to nalidixic acid 40.5% (34/84), ciprofloxacin 11.9% (10/84), azithromycin 8.3% (7/84), and erythromycin 3.6% (3/84). Regarding the ten virulence genes detected, cj1349, mviN and pldA had the highest prevalence 100% (84/84), followed by tlyA 98.8% (83/84), cadF 97.6% (82/84), ciaB 71.4% (60/84), hecA and hecB 22.6% (19/84), iroE 15.5% (13/84) and irgA 10.7% (9/84), respectively. Three virulence genes were present among A. butzleri isolates of human diarrheal stool and food samples, with a significant difference observed among isolates; hecB [36% (9/25) and 8.6% (3/35)], hecA [36% (9/25) and 5.7% (2/35)], and irgA [24% (6/25) and 2.9% (1/35)] (p < 0.05), respectively. The hecA and hecB virulence genes functions are related to the mechanism of hemolysis, while irgA supports a bacterial nutritional requirement. MLST analysis of 26 A. butzleri isolates revealed that 16 novel STs exhibited high genetic diversity. The results of this study is useful for understanding potentially pathogenic and antimicrobial-resistant A. butzleri in Thailand. The pathogenic virulence markers hecB, hecA, and irgA have the potential to be developed for rapid diagnostic detection in human diarrheal stool. No significant relationships among STs and sources of origin were observed. Little is known about A. butzleri, the mechanism of action of these virulence genes, is a topic that needs further investigation.
Topics: Animals; Arcobacter; Diarrhea; Genes, Bacterial; Genotype; Gram-Negative Bacterial Infections; Humans; Multilocus Sequence Typing; Thailand; Virulence Factors
PubMed: 33544770
DOI: 10.1371/journal.pone.0246598 -
Applied and Environmental Microbiology Apr 2020Pathogenic bacteria in wastewater are generally considered to be efficiently removed in biological wastewater treatment plants. This understanding is almost solely based...
Pathogenic bacteria in wastewater are generally considered to be efficiently removed in biological wastewater treatment plants. This understanding is almost solely based on culture-based control measures, and here we show, by applying culture-independent methods, that the removal of species in the genus was less effective than for many other abundant genera in the influent wastewater. was one of the most abundant genera in influent wastewater at 14 municipal wastewater treatment plants and was also abundant in the "clean" effluent from all the plants, reaching up to 30% of all bacteria as analyzed by 16S rRNA gene amplicon sequencing. Metagenomic analyses, culturing, genome sequencing of isolates, and visualization by fluorescent hybridization (FISH) confirmed the presence of the human-pathogenic and in both influent and effluent. The main reason for the high relative abundance in the effluent was probably that cells, compared to those of other abundant genera in the influent, did not flocculate and attach well to the activated sludge flocs, leaving a relatively large fraction dispersed in the water phase. The study shows there is an urgent need for new standardized culture-independent measurements of pathogens in effluent wastewaters, e.g., amplicon sequencing, and an investigation of the problem on a global scale to quantify the risk for humans and livestock. The genus was unexpectedly abundant in the effluent from 14 Danish wastewater treatment plants treating municipal wastewater, and the species included the human-pathogenic and Recent studies have shown that is common in wastewater worldwide, so the study indicates that discharge of members of the genus may be a global problem, and further studies are needed to quantify the risk and potentially minimize the discharge. The study also shows that culture-based analyses are insufficient for proper effluent quality control, and new standardized culture-independent measurements of effluent quality encompassing most pathogens should be considered.
Topics: Arcobacter; Denmark; RNA, Bacterial; RNA, Ribosomal, 16S; Waste Disposal, Fluid; Wastewater
PubMed: 32111585
DOI: 10.1128/AEM.03044-19 -
IScience Mar 2021Mangrove-dominated estuaries host a diverse microbial assemblage that facilitates nutrient and carbon conversions and could play a vital role in maintaining ecosystem...
Mangrove-dominated estuaries host a diverse microbial assemblage that facilitates nutrient and carbon conversions and could play a vital role in maintaining ecosystem health. In this study, we used 16S rRNA gene analysis, metabolic inference, nutrient concentrations, and δC and δN isotopes to evaluate the impact of land use change on near-shore biogeochemical cycles and microbial community structures within mangrove-dominated estuaries. Samples in close proximity to active shrimp aquaculture were high in NH , NO NO , and PO ; lower in microbial community and metabolic diversity; and dominated by putative nitrifiers, denitrifies, and sulfur-oxidizing bacteria. Near intact mangrove forests we observed the presence of potential nitrogen fixers of the genus and order Rhizobiales. We identified possible indicators of aquaculture effluents such as family Chromatiaceae and genus These results highlight the sensitivity of the estuarine-mangrove microbial community, and their ecosystem functions, to land use changes.
PubMed: 33786421
DOI: 10.1016/j.isci.2021.102204 -
Case Reports in Infectious Diseases 2022is an emerging enteric pathogen increasingly identified in Europe and is likely under-reported in other global regions. We describe to our knowledge the first case...
BACKGROUND
is an emerging enteric pathogen increasingly identified in Europe and is likely under-reported in other global regions. We describe to our knowledge the first case report of in an AIDS patient, along with the first documented local (Singapore) case of infection. . A 38-year-old AIDS patient presented with diarrhoea of 2 weeks' duration. Stool cultures yielded . The patient was treated with 3 days of ciprofloxacin with clinical resolution of diarrhoea.
CONCLUSION
is likely to be present, although under-reported in AIDS patients, and it should be noted as a pathogen of increasing significance.
PubMed: 35847602
DOI: 10.1155/2022/6983094 -
Pathogens (Basel, Switzerland) Oct 2021Water is vital to agriculture. It is essential that the water used for the production of fresh produce commodities be safe. Microbial pathogens are able to survive for... (Review)
Review
Water is vital to agriculture. It is essential that the water used for the production of fresh produce commodities be safe. Microbial pathogens are able to survive for extended periods of time in water. It is critical to understand their biology and ecology in this ecosystem in order to develop better mitigation strategies for farmers who grow these food crops. In this review the prevalence, persistence and ecology of four major foodborne pathogens, Shiga toxin-producing (STEC), , and closely related , and , in water are discussed. These pathogens have been linked to fresh produce outbreaks, some with devastating consequences, where, in a few cases, the contamination event has been traced to water used for crop production or post-harvest activities. In addition, antimicrobial resistance, methods improvements, including the role of genomics in aiding in the understanding of these pathogens, are discussed. Finally, global initiatives to improve our knowledge base of these pathogens around the world are touched upon.
PubMed: 34832547
DOI: 10.3390/pathogens10111391 -
Environmental Research Mar 2022This study aims to compare the effects of different carbon sources on sulfur-oxidizing denitrifying microorganisms by using glucose, ethanol, and acetate as carbon...
This study aims to compare the effects of different carbon sources on sulfur-oxidizing denitrifying microorganisms by using glucose, ethanol, and acetate as carbon sources. Under the same chemical oxygen demand Cr (COD), nitrate, and sulfide concentrations, the removal rate of nitrate and total organic carbon, and the yield of elemental sulfur in a static experiment and a continuous flow reactor with glucose as the carbon source were lower than those with ethanol and acetic acid as the carbon source. The core sulfur-oxidizing denitrifying bacteria that use glucose as the carbon source were Azoarcus, Geoalkalibacter, and Mangroviflexus; those that use ethanol as the carbon source were Arcobacter, Pseudomonas, and Thauera; those that use acetate as the carbon source were Pseudomonas and Azoarcus. The metabolic activity of microorganisms that use different carbon sources was explained by functional gene detection. The fluctuation of gltA, a functional gene indicating heterotrophic metabolism of microorganisms, was small in three reactors, but that of the sulfur oxidation gene, Sqr, in the reactor with acetic acid as the carbon source was larger. Our results suggest that acetate is a more suitable carbon source for denitrification-desulfurization systems.
Topics: Bioreactors; Carbon; Denitrification; Nitrates; Oxidation-Reduction; Sulfur
PubMed: 34453896
DOI: 10.1016/j.envres.2021.111946 -
Gut Pathogens 2020species, particularly , but also constitute emerging pathogens causing gastroenteritis in humans. However, isolation of may often fail during routine diagnostic...
BACKGROUND
species, particularly , but also constitute emerging pathogens causing gastroenteritis in humans. However, isolation of may often fail during routine diagnostic procedures due to the lack of standard protocols. Furthermore, defined breakpoints for the interpretation of antimicrobial susceptibilities of are missing. Hence, reliable epidemiological data of human infections are scarce and lacking for Germany. We therefore performed a 13-month prospective prevalence study in German patients.
RESULTS
A total of 4636 human stool samples was included and spp. were identified from 0.85% of specimens in 3884 outpatients and from 0.40% of specimens in 752 hospitalized patients. Overall, was the most prevalent species (n = 24; 67%), followed by (n = 10; 28%) and (n = 2; 6%). Whereas and were identified in outpatients, only could be isolated from samples of hospitalized patients. Antimicrobial susceptibility testing of isolates revealed high susceptibilities to ciprofloxacin, whereas bimodal distributions of MICs were observed for azithromycin and ampicillin.
CONCLUSIONS
In summary, including , and could be isolated in 0.85% of German outpatients and ciprofloxacin rather than other antibiotics might be appropriate for antibiotic treatment of infections. Further epidemiological studies are needed, however, to provide a sufficient risk assessment of infections in humans.
PubMed: 32322308
DOI: 10.1186/s13099-020-00360-x -
Microbial Pathogenesis Mar 2021Arcobacter spp colonize in human and animals intestine and cause food-associated infections. Hence, characterization of their virulence potential and health impacts is...
Arcobacter spp colonize in human and animals intestine and cause food-associated infections. Hence, characterization of their virulence potential and health impacts is required. Our subject was isolation and characterization of Arcobacter spp, from meat marketplaces. A total of 1297 fresh raw cattle meat samples were purchased randomly from various marketplaces in Baghdad, Iraq. One-hundred and twenty isolates were identified, including Arcobacter butzleri (A. butzleri n = 100) and Arcobacter cryaerophilus (A. cryaerophilus n = 20). Susceptibility to antimicrobials was examined using Kirby-Bauer disc diffusion method. Molecular investigation of antibiotic resistance and virulence factors was also conducted using polymerase chain reaction (PCR) technique. Most of A. butzleri were resistant to tetracycline (72%), amoxicillin (69%), erythromycin (67%) and cefoxitin (66%), while 33% and 6% of them were resistant to ceftazidime and carbapenems, respectively. All were susceptible to gentamicin, colistin and fosfomycin. Fifty-five and nine isolates of A. butzleri and A. cryaerophilus were respectively multidrug-resistant (MDR). The existence of tetA, tetB, dfrA, sul1, bla and bla included 61%, 58%, 57%, 34%, 46% and 3%, respectively. The virulence genes cadF, irgA, tylA, cdtC and cdtA genes were detected in all the A. butzleri and A. cryaerophilus isolates. While, ciaB mviN and pldA genes were respectively detected in 91%, 88% and 84% of A. butzleri and 97%, 93% and 87% of A. cryaerophilus isolates. There was a significant relation between MDR and existence of virulence genes. Existence of pathogenic and drug-resistant- Arcobacter spp in raw meat is a threat for human health, necessitating confirmation of quality and safety of meat products.
Topics: Animals; Arcobacter; Cattle; Food Microbiology; Iraq; Meat; Meat Products; Virulence Factors
PubMed: 33249163
DOI: 10.1016/j.micpath.2020.104649 -
Microorganisms Sep 2021is the most frequent cause of bacterial gastrointestinal food-borne infection worldwide. The transmission of and -like species is often made possible by their...
is the most frequent cause of bacterial gastrointestinal food-borne infection worldwide. The transmission of and -like species is often made possible by their ability to adhere to various abiotic surfaces. This study is focused on monitoring the biofilm ability of 69 strains of spp. and lesser described species of the family isolated from food, water, and clinical samples within the Czech Republic. Biofilm formation was monitored and evaluated under an aerobic/microaerophilic atmosphere after cultivation for 24 or 72 h depending on the surface material. An overall higher adhesion ability was observed in arcobacters. A chi-squared test showed no association between the origin of the strains and biofilm activity ( > 0.05). -like species are able to form biofilms under microaerophilic and aerobic conditions; however, they prefer microaerophilic environments. Biofilm formation has already been demonstrated at refrigerator temperatures (5 °C). Arcobacters also showed higher biofilm formation ability at the temperature of 30 °C. This is in contrast to NP 2896, which showed higher biofilm formation ability at temperatures of 5-30 °C. Overall, the results demonstrated the biofilm formation ability of many strains, which poses a considerable risk to the food industry, medical practice, and human health.
PubMed: 34683338
DOI: 10.3390/microorganisms9102017 -
The Science of the Total Environment Mar 2023Municipal sewage sludge has been generated in increasing amounts with the acceleration of urbanization and economic development. The nutrient rich sewage sludge can be...
Municipal sewage sludge has been generated in increasing amounts with the acceleration of urbanization and economic development. The nutrient rich sewage sludge can be recycled by composting that has a great potential to produce stabilized organic fertilizer and substrate for plant cultivation. However, little is known about the metals, pathogens and antibiotic resistance transfer risks involved in applying the composted sludge in agriculture. We studied changes in and relationships between heavy metal contents, microbial communities, and antibiotic resistance genes (ARGs), heavy metal resistance genes (HMRGs) and mobile genetic elements (MGEs) in aerobic composting of sewage sludge. The contents of most of the analyzed heavy metals were not lower after composting. The bacterial α-diversity was lower, and the community composition was different after composting. Firmicutes were enriched, and Proteobacteria and potential pathogens in the genera Arcobacter and Acinetobacter were depleted in the composted sludge. The differences in bacteria were possibly due to the high temperature phase during the composting which was likely to affect temperature-sensitive bacteria. The number of detected ARGs, HMRGs and MGEs was lower, and the relative abundances of several resistance genes were lower after composting. However, the abundance of seven ARGs and six HMRGs remained on the same level after composting. Co-occurrence analysis of bacterial taxa and the genes suggested that the ARGs may spread via horizontal gene transfer during composting. In summary, even though aerobic composting is effective for managing sewage sludge and to decrease the relative abundance of potential pathogens, ARGs and HMRGs, it might include a potential risk for the dissemination of ARGs in the environment.
Topics: Anti-Bacterial Agents; Sewage; Genes, Bacterial; Composting; Metals, Heavy; Bacteria; Manure
PubMed: 36608829
DOI: 10.1016/j.scitotenv.2023.161386