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Frontiers in Microbiology 2019The Campylobacterota, previously known as Epsilonproteobacteria, are a large group of Gram-negative mainly, spiral-shaped motile bacteria. Some members like the spp.... (Review)
Review
The Campylobacterota, previously known as Epsilonproteobacteria, are a large group of Gram-negative mainly, spiral-shaped motile bacteria. Some members like the spp. are free-living, while others such as spp. can only persist in strict association with a host organism as commensal or as pathogen. Species of this phylum colonize diverse habitats ranging from deep-sea thermal vents to the human stomach wall. Despite their divergent environments, they share common energy conservation mechanisms. The Campylobacterota have a large and remarkable repertoire of electron transport chain enzymes, given their small genomes. Although members of recognized families of transcriptional regulators are found in these genomes, sofar no orthologs known to be important for energy or redox metabolism such as ArcA, FNR or NarP are encoded in the genomes of the Campylobacterota. In this review, we discuss the strategies that members of Campylobacterota utilize to conserve energy and the corresponding regulatory mechanisms that regulate the branched electron transport chains in these bacteria.
PubMed: 31417516
DOI: 10.3389/fmicb.2019.01719 -
FEMS Microbiology Ecology Dec 2022Planktonic particle-associated bacteria comprise particle-attached and motile free-living cells. These groups were obtained by settlement in Imhoff cones. Dilution...
Planktonic particle-associated bacteria comprise particle-attached and motile free-living cells. These groups were obtained by settlement in Imhoff cones. Dilution plating on marine agar 2216 (ZoBell marine agar) and microscopic counts indicated a cultivability of 0.7% (0.4%-1.2%) of bacteria in coastal seawater collected at Helgoland Roads, North Sea. Particle-associated bacteria presented a minority population in seawater, but had a larger cultivability of 25% (0.9%-100%) for populations collected by settlement of particles and 5.7% (0.9%-24%) for populations collected by filtration. Partial 16S rRNA gene sequences indicated that 84% of the cultured taxa were either enriched in particle-associated microbiomes or only found in these microbiomes, including Sulfitobacter and other Rhodobacteraceae, Pseudoalteromonas, Psychromonas, Arcobacter and many Flavobacteriaceae. Illumina-based 16S rRNA V3V4 amplicon sequences of plate communities revealed that nearly all operational taxonomic units had a cultivated and described strain in close phylogenetic proximity. This suggested that decades of strain isolation from seawater on ZoBell marine agar had achieved a very good coverage of cultivable genera abundant in nature. The majority belonged to particle-associated bacteria, complementing observations that abundant free-living seawater bacteria often require cultivation conditions closer to their natural habitat like liquid cultivation in oligotrophic medium.
Topics: Agar; Phylogeny; RNA, Ribosomal, 16S; DNA, Bacterial; Sequence Analysis, DNA; Seawater; Flavobacteriaceae; Microbiota
PubMed: 36513318
DOI: 10.1093/femsec/fiac151 -
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 -
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 -
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 -
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 -
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 -
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 -
Food Science and Biotechnology May 2023is a traditionally fermented cabbage, with a unique taste and beneficial properties, in northeast China. The taste and flavor of vary from region to region, owing to...
is a traditionally fermented cabbage, with a unique taste and beneficial properties, in northeast China. The taste and flavor of vary from region to region, owing to the differences in microorganisms. Illumina MiSeq sequencing was used to identify and quantify the microbial community composition of the broth and leaves of the naturally fermented collected from northeast China. The alpha and beta diversity of the samples from three areas in Heilongjiang province shown that the complexity of bacterial diversity of the three samples was C, A and B in turn. The widely existed in fermented , of these, , subsp. , subsp. , and were more abundant in the leaves than in fermentation broth. Other genera of lactic acid bacteria and , which have potential probiotic properties, were also present. However, some harmful bacteria such as and were also detected.
PubMed: 37041807
DOI: 10.1007/s10068-022-01221-w -
Food Microbiology Apr 2024Infection mechanisms of Arcobacter remain uncertain. This study aimed to determine whether 65 food and waterborne isolates of at least six species were able to adhere...
Infection mechanisms of Arcobacter remain uncertain. This study aimed to determine whether 65 food and waterborne isolates of at least six species were able to adhere and invade Caco-2 cells; and whether this ability could be related to cadF, cj1349, ciaB, and/or hecA, specific genetic markers related to host cell adhesion and invasion. All adhered and invaded the cells, and harboured at least two virulence markers. The mean virulent activity shown by A. butzleri was superior to that of A. cryaerophilus (p < 0.05); but the mean adhesion and invasion values of A. lanthieri, A. skirrowii, and A. vitoriensis were even higher. Sewage isolates were significantly (p < 0.05) more adherent and invasive than the rest, and their associated gene content was higher (p < 0.05). For the first time, an association between cadF and hecA and a high adhesion capability was identified (p < 0.05). The results provide new data on the pathogenic potential of Arcobacter species present in food and water by highlighting the superiority of A. butzleri over A. cryarophilus; providing evidence on the virulence of minority species as A. lanthieri and A. vitoriensis; and confirming sewage as an important source of potentially more virulent arcobacters.
Topics: Humans; Virulence Factors; Arcobacter; Caco-2 Cells; Sewage; Meat
PubMed: 38049262
DOI: 10.1016/j.fm.2023.104424