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Archives of Microbiology Jan 2021Shigella sonnei is the emerging pathogen globally, as it is the second common infectious species of shigellosis (bloody diarrhoea) in low- and middle-income countries... (Review)
Review
Shigella sonnei is the emerging pathogen globally, as it is the second common infectious species of shigellosis (bloody diarrhoea) in low- and middle-income countries (LMICs) and the leading one in developed world. The multifactorial processes and novel mechanisms have been identified in S. sonnei, that are collectively playing apart a substantial role in increasing its prevalence, while replacing the S. flexneri and other Gram-negative gut pathogens niche occupancy. Recently, studies suggest that due to improvement in sanitation S. sonnei has reduced cross-immunization from Plesiomonas shigelliodes (having same O-antigen as S. sonnei) and also found to outcompete the two major species of Enterobacteriaceae family (Shigella flexneri and Escherichia coli), due to encoding of type VI secretion system (T6SS). This review aimed to highlight S. sonnei as an emerging pathogen in the light of recent research with pondering aspects on its epidemiology, transmission, and pathogenic mechanisms. Additionally, this paper aimed to review S. sonnei disease pattern and related complications, symptoms, and laboratory diagnostic techniques. Furthermore, the available treatment reigns and antibiotic-resistance patterns of S. sonnei are also discussed, as the ciprofloxacin and fluoroquinolone-resistant S. sonnei has already intensified the global spread and burden of antimicrobial resistance. In last, prevention and controlling strategies are briefed to limit and tackle S. sonnei and possible future areas are also explored that needed more research to unravel the hidden mysteries surrounding S. sonnei.
Topics: Anti-Bacterial Agents; Ciprofloxacin; Drug Resistance, Bacterial; Dysentery, Bacillary; Escherichia coli; Fluoroquinolones; Humans; Shigella flexneri; Shigella sonnei; Type VI Secretion Systems
PubMed: 32929595
DOI: 10.1007/s00203-020-02034-3 -
Journal of Clinical Microbiology Mar 2015The appropriate treatment and control of infectious gastroenteritis depend on the ability to rapidly detect the wide range of etiologic agents associated with the...
The appropriate treatment and control of infectious gastroenteritis depend on the ability to rapidly detect the wide range of etiologic agents associated with the disease. Clinical laboratories currently utilize an array of different methodologies to test for bacterial, parasitic, and viral causes of gastroenteritis, a strategy that suffers from poor sensitivity, potentially long turnaround times, and complicated ordering practices and workflows. Additionally, there are limited or no testing methods routinely available for most diarrheagenic Escherichia coli strains, astroviruses, and sapoviruses. This study assessed the performance of the FilmArray Gastrointestinal (GI) Panel for the simultaneous detection of 22 different enteric pathogens directly from stool specimens: Campylobacter spp., Clostridium difficile (toxin A/B), Plesiomonas shigelloides, Salmonella spp., Vibrio spp., Vibrio cholerae, Yersinia enterocolitica, enteroaggregative E. coli, enteropathogenic E. coli, enterotoxigenic E. coli, Shiga-like toxin-producing E. coli (stx1 and stx2) (including specific detection of E. coli O157), Shigella spp./enteroinvasive E. coli, Cryptosporidium spp., Cyclospora cayetanensis, Entamoeba histolytica, Giardia lamblia, adenovirus F 40/41, astrovirus, norovirus GI/GII, rotavirus A, and sapovirus. Prospectively collected stool specimens (n = 1,556) were evaluated using the BioFire FilmArray GI Panel and tested with conventional stool culture and molecular methods for comparison. The FilmArray GI Panel sensitivity was 100% for 12/22 targets and ≥94.5% for an additional 7/22 targets. For the remaining three targets, sensitivity could not be calculated due to the low prevalences in this study. The FilmArray GI Panel specificity was ≥97.1% for all panel targets. The FilmArray GI Panel provides a comprehensive, rapid, and streamlined alternative to conventional methods for the etiologic diagnosis of infectious gastroenteritis in the laboratory setting. The potential advantages include improved performance parameters, a more extensive menu of pathogens, and a turnaround time of as short as 1 h.
Topics: Adolescent; Adult; Aged; Aged, 80 and over; Animals; Bacteria; Child; Child, Preschool; Feces; Female; Gastroenteritis; Humans; Infant; Infant, Newborn; Male; Microbiological Techniques; Middle Aged; Molecular Diagnostic Techniques; Parasites; Prospective Studies; Sensitivity and Specificity; Time Factors; Viruses; Young Adult
PubMed: 25588652
DOI: 10.1128/JCM.02674-14 -
Clinical Microbiology Reviews Apr 2016After many years in the family Vibrionaceae, the genus Plesiomonas, represented by a single species, P. shigelloides, currently resides in the family Enterobacteriaceae,... (Review)
Review
After many years in the family Vibrionaceae, the genus Plesiomonas, represented by a single species, P. shigelloides, currently resides in the family Enterobacteriaceae, although its most appropriate phylogenetic position may yet to be determined. Common environmental reservoirs for plesiomonads include freshwater ecosystems and estuaries and inhabitants of these aquatic environs. Long suspected as being an etiologic agent of bacterial gastroenteritis, convincing evidence supporting this conclusion has accumulated over the past 2 decades in the form of a series of foodborne outbreaks solely or partially attributable to P. shigelloides. The prevalence of P. shigelloides enteritis varies considerably, with higher rates reported from Southeast Asia and Africa and lower numbers from North America and Europe. Reasons for these differences may include hygiene conditions, dietary habits, regional occupations, or other unknown factors. Other human illnesses caused by P. shigelloides include septicemia and central nervous system disease, eye infections, and a variety of miscellaneous ailments. For years, recognizable virulence factors potentially associated with P. shigelloides pathogenicity were lacking; however, several good candidates now have been reported, including a cytotoxic hemolysin, iron acquisition systems, and lipopolysaccharide. While P. shigelloides is easy to identify biochemically, it is often overlooked in stool samples due to its smaller colony size or relatively low prevalence in gastrointestinal samples. However, one FDA-approved PCR-based culture-independent diagnostic test system to detect multiple enteropathogens (FilmArray) includes P. shigelloides on its panel. Plesiomonads produce β-lactamases but are typically susceptible to many first-line antimicrobial agents, including quinolones and carbapenems.
Topics: Foodborne Diseases; Gram-Negative Bacterial Infections; Humans; Molecular Diagnostic Techniques; Phylogeny; Plesiomonas; Water Microbiology
PubMed: 26960939
DOI: 10.1128/CMR.00103-15 -
TheScientificWorldJournal 2021Fish and fish products are considered a fundamental part of the human diet due to their high nutritional value. Food-borne diseases are considered a major public health... (Review)
Review
Fish and fish products are considered a fundamental part of the human diet due to their high nutritional value. Food-borne diseases are considered a major public health challenge worldwide due to their incidence, associated mortality, and negative economic repercussions. Food safety is the guarantee that foods will not cause harm to the health of those who consume them, and it is a fundamental property of food quality. Food safety can be at risk of being lost at any stage of the food chain if the food is contaminated by pathogenic microorganisms. Many diverse bacteria are present in the environment and as part of the microbiota of food that can be transmitted to humans during the handling and consumption of food. has been mainly associated with outbreaks of gastrointestinal diseases due to the consumption of fish. This bacterium inhabits the environment and aquatic animals and is associated with the microbiota of fish such as tilapia, a fish of importance in fishing, aquaculture, commercialization, and consumption worldwide. The purpose of this document is to provide, through a bibliographic review of databases (Scopus, Web of Science, and Google Scholar, among others), a general informative perspective on food-borne diseases and, in particular, the consumption of fish and tilapia. Diseases derived from contamination by are included, and control and prevention actions and sanitary regulations for fishery products established in several countries around the world are discussed to promote the safety of foods of aquatic origin intended for human consumption and to protect public health.
Topics: Animals; Aquaculture; Bacterial Load; Cryopreservation; Disease Reservoirs; Fish Diseases; Fish Products; Food Contamination; Food Handling; Food Microbiology; Food Preservation; Food Safety; Gastroenteritis; Gram-Negative Bacterial Infections; Humans; Plesiomonas; Prevalence; Quality Control; Seafood; Tilapia; Water Pollution
PubMed: 34594160
DOI: 10.1155/2021/3119958 -
Microbiology Spectrum Oct 2022Maintaining the health of seafarers is a difficult task during long-term voyages. Little is known about the corresponding changes in the gut microbiome-host interaction....
Maintaining the health of seafarers is a difficult task during long-term voyages. Little is known about the corresponding changes in the gut microbiome-host interaction. This study recruited 30 seafarers undertaking a 6-month voyage and analyzed their gut microbiota using 16S rRNA gene sequencing. Fecal untargeted metabolomics analysis was performed using liquid chromatography-mass spectrometry. Significant changes in the composition of the gut microbiota and an increased ratio of / at the end (day 180) of the 6-month voyage, relative to the start (day 0), were observed. At the genus level, the abundances of and were significantly increased, while the abundance of was decreased. Predicted microbial functional analysis revealed significant decreases in folate biosynthesis and biotin metabolism. Furthermore, 20 differential metabolites within six differentially enriched human metabolic pathways (including arginine biosynthesis, lysine degradation, phenylalanine metabolism, sphingolipid metabolism, pentose and glucuronate interconversions, and glycine, serine, and threonine metabolism) were identified by comparing the fecal metabolites at day 0 and day 180. Spearman correlation analysis revealed close relationships between the 14 differential microbiota members and the six differential fecal metabolites that might affect specific human metabolic pathways. This study adopted a multi-omics approach and provides potential targets for maintaining the health of seafarers during long-term voyages. These findings are worthy of more in-depth exploration in future studies. Maintaining the health of seafarers undertaking long-term voyages is a difficult task. Apart from the alterations in the gut microbiome and fecal metabolites after a long-term voyage, our study also revealed that 20 differential metabolites within six differentially enriched human metabolic pathways are worthy of attention. Moreover, we found close relationships between the 14 differential microbiota members and the six differential fecal metabolites that might impact specific human metabolic pathways. Accordingly, preventative measures, such as adjusting the gut microbiota by decreasing potential pathobionts or increasing potential probiotics as well as offsetting the decrease in B vitamins and beneficial metabolites (e.g., d-glucuronic acid and citrulline) via dietary adjustment or nutritional supplements, might improve the health of seafarers during long-term sea voyages. These findings provide valuable clues about gut microbiome-host interactions and propose potential targets for maintaining the health of seafarers engaged in long-term sea voyages.
Topics: Humans; Gastrointestinal Microbiome; RNA, Ribosomal, 16S; Vitamin B Complex; Citrulline; Biotin; Lysine; Metabolomics; Feces; Pentoses; Glucuronates; Glycine; Glucuronic Acid; Serine; Phenylalanine; Sphingolipids; Threonine; Arginine; Folic Acid
PubMed: 36197290
DOI: 10.1128/spectrum.01899-22 -
FEMS Microbiology Reviews Jul 2008This review covers the O antigens of the 46 serotypes of Shigella, but those of most Shigella flexneri are variants of one basic structure, leaving 34 Shigella distinct... (Comparative Study)
Comparative Study Review
This review covers the O antigens of the 46 serotypes of Shigella, but those of most Shigella flexneri are variants of one basic structure, leaving 34 Shigella distinct O antigens to review, together with their gene clusters. Several of the structures and gene clusters are reported for the first time and this is the first such group for which structures and DNA sequences have been determined for all O antigens. Shigella strains are in effect Escherichia coli with a specific mode of pathogenicity, and 18 of the 34 O antigens are also found in traditional E. coli. Three are very similar to E. coli O antigens and 13 are unique to Shigella strains. The O antigen of Shigella sonnei is quite atypical for E. coli and is thought to have transferred from Plesiomonas. The other 12 O antigens unique to Shigella strains have structures that are typical of E. coli, but there are considerably more anomalies in their gene clusters, probably reflecting recent modification of the structures. Having the complete set of structures and genes opens the way for experimental studies on the role of this diversity in pathogenicity.
Topics: Bacterial Proteins; Biosynthetic Pathways; Carbohydrate Sequence; Dysentery, Bacillary; Escherichia coli; Escherichia coli Infections; Humans; Molecular Sequence Data; Multigene Family; Mutation; O Antigens; Shigella
PubMed: 18422615
DOI: 10.1111/j.1574-6976.2008.00114.x -
BMC Microbiology Dec 2022RpoN, also known as σ, first reported in Escherichia coli, is a subunit of RNA polymerase that strictly controls the expression of different genes by identifying...
BACKGROUND
RpoN, also known as σ, first reported in Escherichia coli, is a subunit of RNA polymerase that strictly controls the expression of different genes by identifying specific promoter elements. RpoN has an important regulatory function in carbon and nitrogen metabolism and participates in the regulation of flagellar synthesis, bacterial motility and virulence. However, little is known about the effect of RpoN in Plesiomonas shigelloides.
RESULTS
To identify pathways controlled by RpoN, RNA sequencing (RNA-Seq) of the WT and the rpoN deletion strain was carried out for comparison. The RNA-seq results showed that RpoN regulates ~ 13.2% of the P. shigelloides transcriptome, involves amino acid transport and metabolism, glycerophospholipid metabolism, pantothenate and CoA biosynthesis, ribosome biosynthesis, flagellar assembly and bacterial secretion system. Furthermore, we verified the results of RNA-seq using quantitative real-time reverse transcription PCR, which indicated that the absence of rpoN caused downregulation of more than half of the polar and lateral flagella genes in P. shigelloides, and the ΔrpoN mutant was also non-motile and lacked flagella. In the present study, the ability of the ΔrpoN mutant to kill E. coli MG1655 was reduced by 54.6% compared with that of the WT, which was consistent with results in RNA-seq, which showed that the type II secretion system (T2SS-2) genes and the type VI secretion system (T6SS) genes were repressed. By contrast, the expression of type III secretion system genes was largely unchanged in the ΔrpoN mutant transcriptome and the ability of the ΔrpoN mutant to infect Caco-2 cells was also not significantly different compared with the WT.
CONCLUSIONS
We showed that RpoN is required for the motility and contributes to the killing ability of P. shigelloides and positively regulates the T6SS and T2SS-2 genes.
Topics: Humans; RNA Polymerase Sigma 54; Gene Expression Regulation, Bacterial; Plesiomonas; Bacterial Proteins; Escherichia coli; Caco-2 Cells
PubMed: 36510135
DOI: 10.1186/s12866-022-02722-8 -
BMC Genomics Mar 2022The ability of animals and their microbiomes to adapt to starvation and then restore homeostasis after refeeding is fundamental to their continued survival and...
BACKGROUND
The ability of animals and their microbiomes to adapt to starvation and then restore homeostasis after refeeding is fundamental to their continued survival and symbiosis. The intestine is the primary site of nutrient absorption and microbiome interaction, however our understanding of intestinal adaptations to starvation and refeeding remains limited. Here we used RNA sequencing and 16S rRNA gene sequencing to uncover changes in the intestinal transcriptome and microbiome of zebrafish subjected to long-term starvation and refeeding compared to continuously fed controls.
RESULTS
Starvation over 21 days led to increased diversity and altered composition in the intestinal microbiome compared to fed controls, including relative increases in Vibrio and reductions in Plesiomonas bacteria. Starvation also led to significant alterations in host gene expression in the intestine, with distinct pathways affected at early and late stages of starvation. This included increases in the expression of ribosome biogenesis genes early in starvation, followed by decreased expression of genes involved in antiviral immunity and lipid transport at later stages. These effects of starvation on the host transcriptome and microbiome were almost completely restored within 3 days after refeeding. Comparison with published datasets identified host genes responsive to starvation as well as high-fat feeding or microbiome colonization, and predicted host transcription factors that may be involved in starvation response.
CONCLUSIONS
Long-term starvation induces progressive changes in microbiome composition and host gene expression in the zebrafish intestine, and these changes are rapidly reversed after refeeding. Our identification of bacterial taxa, host genes and host pathways involved in this response provides a framework for future investigation of the physiological and ecological mechanisms underlying intestinal adaptations to food restriction.
Topics: Animals; Intestines; Microbiota; RNA, Ribosomal, 16S; Transcriptome; Zebrafish
PubMed: 35317738
DOI: 10.1186/s12864-022-08447-2 -
Marine Drugs 2011Marine microorganisms have evolved for millions of years to survive in the environments characterized by one or more extreme physical or chemical parameters, e.g., high... (Review)
Review
Marine microorganisms have evolved for millions of years to survive in the environments characterized by one or more extreme physical or chemical parameters, e.g., high pressure, low temperature or high salinity. Marine bacteria have the ability to produce a range of biologically active molecules, such as antibiotics, toxins and antitoxins, antitumor and antimicrobial agents, and as a result, they have been a topic of research interest for many years. Among these biologically active molecules, the carbohydrate antigens, lipopolysaccharides (LPSs, O-antigens) found in cell walls of gram-negative marine bacteria, show great potential as candidates in the development of drugs to prevent septic shock due to their low virulence. The structural diversity of LPSs is thought to be a reflection of the ability for these bacteria to adapt to an array of habitats, protecting the cell from being compromised by exposure to harsh environmental stress factors. Over the last few years, the variety of structures of core oligosaccharides and O-specific polysaccharides from LPSs of marine microrganisms has been discovered. In this review, we discuss the most recently encountered structures that have been identified from bacteria belonging to the genera Aeromonas, Alteromonas, Idiomarina, Microbulbifer, Pseudoalteromonas, Plesiomonas and Shewanella of the Gammaproteobacteria phylum; Sulfitobacter and Loktanella of the Alphaproteobactera phylum and to the genera Arenibacter, Cellulophaga, Chryseobacterium, Flavobacterium, Flexibacter of the Cytophaga-Flavobacterium-Bacteroides phylum. Particular attention is paid to the particular chemical features of the LPSs, such as the monosaccharide type, non-sugar substituents and phosphate groups, together with some of the typifying traits of LPSs obtained from marine bacteria. A possible correlation is then made between such features and the environmental adaptations undertaken by marine bacteria.
Topics: Alphaproteobacteria; Antigens, Bacterial; Aquatic Organisms; Biological Products; Flavobacterium; Gammaproteobacteria; Gram-Negative Bacteria; Lipopolysaccharides; Plesiomonas
PubMed: 22073003
DOI: 10.3390/md9101914 -
PloS One 2023Diarrheal diseases are a leading cause of mortality and morbidity, disproportionally affecting persons residing in low and middle-income countries. Accessing...
Diarrheal diseases are a leading cause of mortality and morbidity, disproportionally affecting persons residing in low and middle-income countries. Accessing high-resolution surveillance data to understand community-level etiology and risk remains challenging, particularly in remote and resource limited populations. A multi-year prospective cohort study was conducted in two rural and two peri-urban villages in Cambodia from 2012 to 2018 to describe the epidemiology and etiology of acute diarrheal diseases within the population. Suspected diarrheal episodes among participants were self-reported or detected via routine weekly household visits. Fresh stool and fecal swabs were tested, and acute-illness and follow-up participant questionnaires collected. Of 5027 enrolled participants, 1450 (28.8%) reported at least one diarrheal incident. A total of 4266 individual diarrhea case events were recorded. Diarrhea incidence rate was calculated to be 281.5 persons per 1000 population per year, with an event rate of 664.3 individual diarrhea events occurring per 1000 population per year. Pathogenic Escherichia coli, Aeromonas spp., and Plesiomonas shigelloides were the most prevalent bacterial infections identified. Hookworm and Strongyloides stercoralis were the predominant helminth species, while Blastocystis hominis and Giardia lamblia were the predominant protozoan species found. Norovirus genotype 2 was the predominant virus identified. Mixed infections of two or more pathogens were detected in 36.2% of positive cases. Risk analyses identified unemployed status increased diarrhea risk by 63% (HR = 1.63 [95% CI 1.46, 1.83]). Individuals without access to protected water sources or sanitation facilities were 59% (HR = 1.59 [95% CI 1.49, 1.69]) and 19% (HR = 1.19 [95% CI 1.12, 1.28]) greater risk of contracting diarrhea, respectively. Patient-level surveillance data captured in this long-term study has generated a unique spatiotemporal profile of diarrheal disease in Cambodia. Understanding etiologies, together with associated epidemiological and community-level risk, provides valuable public health insight to support effective planning and delivery of appropriate local population-targeted interventions.
Topics: Humans; Infant; Urban Population; Cambodia; Prospective Studies; Diarrhea; Risk Factors; Escherichia coli
PubMed: 37000848
DOI: 10.1371/journal.pone.0283871