-
Journal of Microbiology (Seoul, Korea) Apr 2005Shigellosis is a global human health problem. Four species of Shigella i.e. S. dysenteriae, S. flexneri, S. boydii and S. sonnei are able to cause the disease. These... (Review)
Review
Shigellosis is a global human health problem. Four species of Shigella i.e. S. dysenteriae, S. flexneri, S. boydii and S. sonnei are able to cause the disease. These species are subdivided into serotypes on the basis of O-specific polysaccharide of the LPS. Shigella dysenteriae type 1 produces severe disease and may be associated with life-threatening complications. The symptoms of shigellosis include diarrhoea and/or dysentery with frequent mucoid bloody stools, abdominal cramps and tenesmus. Shigella spp. cause dysentery by invading the colonic mucosa. Shigella bacteria multiply within colonic epithelial cells, cause cell death and spread laterally to infect and kill adjacent epithelial cells, causing mucosal ulceration, inflammation and bleeding. Transmission usually occurs via contaminated food and water or through person-to-person contact. Laboratory diagnosis is made by culturing the stool samples using selective/differential agar media. Shigella spp. are highly fragile organism and considerable care must be exercised in collecting faecal specimens, transporting them to the laboratories and in using appropriate media for isolation. Antimicrobial agents are the mainstay of therapy of all cases of shigellosis. Due to the global emergence of drug resistance, the choice of antimicrobial agents for treating shigellosis is limited. Although single dose of norfloxacin and ciprofloxacin has been shown to be effective, they are currently less effective against S. dysenteriae type 1 infection. Newer quinolones, cephalosporin derivatives, and azithromycin are the drug of choice. However, fluoroquinolone-resistant S. dysenteriae type 1 infection have been reported. Currently, no vaccines against Shigella infection exist. Both live and subunit parenteral vaccine candidates are under development. Because immunity to Shigella is serotype-specific, the priority is to develop vaccine against S. dysenteriae type 1 and S. flexneri type 2a. Shigella species are important pathogens responsible for diarrhoeal diseases and dysentery occurring all over the world. The morbidity and mortality due to shigellosis are especially high among children in developing countries. A recent review of literature (Kotloff et al.,1999) concluded that, of the estimated 165 million cases of Shigella diarrhoea that occur annually, 99% occur in developing countries, and in developing countries 69% of episodes occur in children under five years of age. Moreover, of the ca.1.1 million deaths attributed to Shigella infections in developing countries, 60% of deaths occur in the under-five age group. Travellers from developed to developing regions and soldiers serving under field conditions are also at an increased risk to develop shigellosis.
Topics: Drug Resistance, Bacterial; Dysentery, Bacillary; Humans; Shigella; Shigella Vaccines; Virulence Factors
PubMed: 15880088
DOI: No ID Found -
Journal of Bacteriology Oct 1963Kohn, J. (Queen Mary's Hospital, London, England) and J. L. Reis. Bacterial nucleotidases. J. Bacteriol. 86:713-716. 1963.-The 3- and 5- nucleotidase activity in various...
Kohn, J. (Queen Mary's Hospital, London, England) and J. L. Reis. Bacterial nucleotidases. J. Bacteriol. 86:713-716. 1963.-The 3- and 5- nucleotidase activity in various bacterial species was investigated. Both enzymes were found in bacterial extracts in varying proportions. The nucleotidases were found to be very active in Proteus vulgaris, in which organism they were studied in detail. The relative activities, the pH optima, and the effect of metal ions were investigated. It was concluded that bacterial 3- and 5-nucleotidases are distinct and separate enzymes.
Topics: Bacillus cereus; Clostridium; Clostridium perfringens; Escherichia coli; Haemophilus influenzae; Magnesium; Manganese; Nickel; Nucleotidases; Proteus; Pseudomonas aeruginosa; Research; Salmonella; Salmonella typhimurium; Serratia marcescens; Shigella dysenteriae; Staphylococcus; Streptococcus pneumoniae; Zinc
PubMed: 14066466
DOI: 10.1128/jb.86.4.713-716.1963 -
Toxins Feb 2017Shiga toxins consist of an A-moiety and five B-moieties able to bind the neutral glycosphingolipid globotriaosylceramide (Gb3) on the cell surface. To intoxicate cells... (Review)
Review
Shiga toxins consist of an A-moiety and five B-moieties able to bind the neutral glycosphingolipid globotriaosylceramide (Gb3) on the cell surface. To intoxicate cells efficiently, the toxin A-moiety has to be cleaved by furin and transported retrogradely to the Golgi apparatus and to the endoplasmic reticulum. The enzymatically active part of the A-moiety is then translocated to the cytosol, where it inhibits protein synthesis and in some cell types induces apoptosis. Protection of cells can be provided either by inhibiting binding of the toxin to cells or by interfering with any of the subsequent steps required for its toxic effect. In this article we provide a brief overview of the interaction of Shiga toxins with cells, describe some compounds and conditions found to protect cells against Shiga toxins, and discuss whether they might also provide protection in animals and humans.
Topics: Animals; Antidotes; Apoptosis; Bacterial Proteins; Dysentery, Bacillary; Hemolytic-Uremic Syndrome; Host-Pathogen Interactions; Humans; Protein Biosynthesis; Protein Conformation; Protein Transport; Shiga Toxins; Shiga-Toxigenic Escherichia coli; Shigella dysenteriae; Structure-Activity Relationship; Trihexosylceramides
PubMed: 28165371
DOI: 10.3390/toxins9020044 -
International Journal of Molecular... Jan 2023species are the main cause of bacillary diarrhoea or shigellosis in humans. These organisms are the inhabitants of the human intestinal tract; however, they are one of... (Review)
Review
species are the main cause of bacillary diarrhoea or shigellosis in humans. These organisms are the inhabitants of the human intestinal tract; however, they are one of the main concerns in public health in both developed and developing countries. In this study, we reviewed and summarised the previous studies and recent advances in molecular mechanisms of pathogenesis of Dysenteriae and non-Dysenteriae species. Regarding the molecular mechanisms of pathogenesis and the presence of virulence factor encoding genes in strains, species of this bacteria are categorised into Dysenteriae and non-Dysenteriae clinical groups. species uses attachment, invasion, intracellular motility, toxin secretion and host cell interruption mechanisms, causing mild diarrhoea, haemorrhagic colitis and haemolytic uremic syndrome diseases in humans through the expression of effector delivery systems, protein effectors, toxins, host cell immune system evasion and iron uptake genes. The investigation of these genes and molecular mechanisms can help us to develop and design new methods to detect and differentiate these organisms in food and clinical samples and determine appropriate strategies to prevent and treat the intestinal and extraintestinal infections caused by these enteric pathogens.
Topics: Humans; Shigella; Shigella dysenteriae; Dysentery, Bacillary; Virulence Factors; Colitis
PubMed: 36768771
DOI: 10.3390/ijms24032448 -
Scientific Reports Jan 2022Shigellosis is characterized as diarrheal disease that causes a high mortality rate especially in children, elderly and immunocompromised patients. More recently, the...
Shigellosis is characterized as diarrheal disease that causes a high mortality rate especially in children, elderly and immunocompromised patients. More recently, the World Health Organization advised safe vaccine designing against shigellosis due to the emergence of Shigella dysenteriae resistant strains. Therefore, the aim of this study is to identify novel drug targets as well as the design of the potential vaccine candidates and chimeric vaccine models against Shigella dysenteriae. A computational based Reverse Vaccinology along with subtractive genomics analysis is one of the robust approaches used for the prioritization of drug targets and vaccine candidates through direct screening of genome sequence assemblies. Herein, a successfully designed peptide-based novel highly antigenic chimeric vaccine candidate against Shigella dysenteriae sd197 strain is proposed. The study resulted in six epitopes from outer membrane WP_000188255.1 (Fe (3+) dicitrate transport protein FecA) that ultimately leads to the construction of twelve vaccine models. Moreover, V9 construct was found to be highly immunogenic, non-toxic, non-allergenic, highly antigenic, and most stable in terms of molecular docking and simulation studies against six HLAs and TLRS/MD complex. So far, this protein and multiepitope have never been characterized as vaccine targets against Shigella dysenteriae. The current study proposed that V9 could be a significant vaccine candidate against shigellosis and to ascertain that further experiments may be applied by the scientific community focused on shigellosis.
Topics: Animals; Anti-Bacterial Agents; Antigens, Bacterial; B-Lymphocytes; Bacterial Proteins; Bacterial Vaccines; Computer-Aided Design; Drug Design; Dysentery, Bacillary; Epitopes; Host-Pathogen Interactions; Humans; Molecular Docking Simulation; Molecular Dynamics Simulation; Network Pharmacology; Shigella dysenteriae; T-Lymphocytes; Vaccine Development; Vaccinology
PubMed: 34997046
DOI: 10.1038/s41598-021-03988-0 -
Frontiers in Cellular and Infection... 2016Shigella is a pathovar of Escherichia coli comprising four groups, Shigella flexneri, Shigella sonnei, Shigella dysenteriae, and Shigella boydii, each of them, with the... (Review)
Review
Shigella is a pathovar of Escherichia coli comprising four groups, Shigella flexneri, Shigella sonnei, Shigella dysenteriae, and Shigella boydii, each of them, with the exception of S.sonnei, comprising several serotypes. Shigella accounts for the majority of dysentery causing infections occurring world-wide each year. Recent advancements in the Shigella field have led to a better understanding of the molecular mechanisms underlying host epithelial cell invasion and immune cell function manipulation, mainly using S. flexneri as a model. Host-cell invasion is the final step of the infection process, as Shigella's virulence strategy relies also on its ability to survive hostile conditions during its journey through the gastro-intestinal tract, to compete with the host microbiota and to cross the intestinal mucus layer. Hence, the diversity of the virulence strategies among the different Shigella species has not yet been deeply investigated, which might be an important step to understand the epidemiological spreading of Shigella species worldwide and a key aspect for the validation of novel vaccine candidates. The recent development of high-throughput screening and sequencing methods will facilitate these complex comparison studies. In this review we discuss several of the major avenues that the Shigella research field has taken over the past few years and hopefully gain some insights into the questions that remain surrounding this important human pathogen.
Topics: Dysentery, Bacillary; Epithelial Cells; Geography; Host-Pathogen Interactions; Humans; Shigella boydii; Shigella dysenteriae; Shigella flexneri; Shigella sonnei
PubMed: 27148494
DOI: 10.3389/fcimb.2016.00045 -
Journal of Microbiology and... May 2023Shiga toxin (Stxs)-producing enterohaemorrhagic (EHEC) and serotype 1 are major causative agents of severe bloody diarrhea (known as hemorrhagic colitis) and hemolytic... (Review)
Review
Shiga toxin (Stxs)-producing enterohaemorrhagic (EHEC) and serotype 1 are major causative agents of severe bloody diarrhea (known as hemorrhagic colitis) and hemolytic uremic syndrome (HUS) associated with extraintestinal complications such as acute renal failure and neurologic impairment in infected patients under 9 years of age. Extreme nephrotoxicity of Stxs in HUS patients is associated with severe outcomes, highlighting the need to develop technologies to detect low levels of the toxin in environmental or food samples. Currently, the conventional polymerase chain reaction (PCR) or immunoassay is the most broadly used assay to detect the toxin. However, these assays are laborious, time-consuming, and costly. More recently, numerous studies have described novel, highly sensitive, and portable methods for detecting Stxs from EHEC. To contextualize newly emerging Stxs detection methods, we briefly explain the basic principles of these methods, including lateral flow assays, optical detection, and electrical detection. We subsequently describe existing and newly emerging rapid detection technologies to identify and measure Stxs.
Topics: Humans; Shiga Toxins; Shiga Toxin; Hemolytic-Uremic Syndrome; Enterohemorrhagic Escherichia coli; Shigella dysenteriae
PubMed: 36859335
DOI: 10.4014/jmb.2212.12025 -
BMC Microbiology Jan 2021The widespread distribution of antimicrobial-resistant Shigella has become a recurrent challenge in many parts of the developing world. Previous studies indicate that...
BACKGROUND
The widespread distribution of antimicrobial-resistant Shigella has become a recurrent challenge in many parts of the developing world. Previous studies indicate that the host of Shigella has expanded from humans to animals. This study aimed to investigate the prevalence of fluoroquinolone resistance and associated molecular characterization of S. dysenteriae 1 isolated from calves.
RESULTS
All 38 unduplicated S. dysenteriae 1 isolates were collected from calves in Gansu Province from October 2014 to December 2016. According to MLST and PFGE analysis, these isolates were separated into 4 and 28 genotypes, respectively. The most common STs identified were ST228 (34.21%, 13/38) and ST229 (39.47%, 15/38), which were first found in the present study. All isolates harbored virulence genes, and the incidence of the seven virulence genes were ipaH (100%), ipaBCD (92.11%), stx (73.68%), ial (57.89%), sen (28.95%), set1A and set1B (0%). According to the results of antimicrobial susceptibilities, 76.32% (29/38) were resistant to fluoroquinolone and showed multidrug resistance. In a study on the polymorphism of quinolone resistance-determining region (QRDR) of gyrA/B and parC/E genes, we identified two mutations in gyrA (Ser83 → Leu and Asp87 → Asn) and parC (Ser80 → Ile and Ser83 → Leu), respectively. Among them, 55.17% (16/29) of resistant strains had the gyrA point mutations (Ser83 → Leu) and parC point mutation (Ser83 → Leu). Moreover, 41.38% (12/29) of isolates had all five point mutations of gyrA and parC. In addition, the prevalence of the plasmid-mediated quinolone resistance (PMQR) determinant genes was also investigated. All 29 fluoroquinolone-resistant isolates were positive for the aac (6')-Ib-cr gene but negative for qepA, except for SD001. In addition, only 6 (20.69%, 6/29) isolates harbored the qnr gene, including two with qnrB (6.90%, 2/29) and four with qnrS (13.79%, 4/29).
CONCLUSION
Given the increased common emergence of multidrug resistant isolates, uninterrupted surveillance will be necessary to understand the actual epidemic burden and control this infection.
Topics: Animals; Bacterial Proteins; Cattle; Cattle Diseases; Drug Resistance, Bacterial; Dysentery, Bacillary; Electrophoresis, Gel, Pulsed-Field; Fluoroquinolones; Gene Expression Regulation, Bacterial; Genotype; Multilocus Sequence Typing; Mutation; Plasmids; Prevalence; Shigella dysenteriae; Virulence Factors
PubMed: 33407134
DOI: 10.1186/s12866-020-02050-9 -
PloS One 2017Shigella dysenteriae (S.dysenteriae) the causative agent of bacillary dysentery invades the human colonic epithelium resulting in severe intestinal inflammatory response...
Shigella dysenteriae (S.dysenteriae) the causative agent of bacillary dysentery invades the human colonic epithelium resulting in severe intestinal inflammatory response and epithelial destruction. However, the mechanism by which S.dysenteriae infection regulates proinflammatory cytokines during intestinal inflammation is still obscure. In this study, we evaluated whether the interaction of β-catenin and NF-κB regulates proinflammatory cytokines TNF-α and IL-8 by modulating GSK-3β activity during S.dysenteriae infection in rat ileal loop model. Here we demonstrated that S.dysenteriae infection stimulate β-catenin degradation which in turn decreased the association between NF-κB and β-catenin. Also, we showed that S.dysenteriae infection increased GSK-3β kinase activity which in turn phosphorylates β-catenin for its degradation by ubiquitination and upregulates IL-8 through NF-κB activation thereby leading to inflammation. Thus these findings revealed the role of β-catenin/ NF-κB and GSK-3β in modulating the inflammatory response during bacterial infection and also showed that β-catenin acts as a critical regulator of inflammation.
Topics: Animals; Cytokines; Dysentery, Bacillary; Humans; Inflammation; Inflammation Mediators; NF-kappa B; Rats; Shigella dysenteriae; Signal Transduction; beta Catenin
PubMed: 28430783
DOI: 10.1371/journal.pone.0174943 -
Travel Medicine and Infectious Disease 2023Southeast Asia is attractive for tourism. Unfortunately, travelers to this region are at risk of becoming infected with Shigella. We conducted a meta-analysis to provide... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Southeast Asia is attractive for tourism. Unfortunately, travelers to this region are at risk of becoming infected with Shigella. We conducted a meta-analysis to provide updates on Shigella prevalence in Southeast Asia, along with their serogroups and serotypes.
METHODS
We conducted a systematic search using PubMed, EMBASE, and Web of Science for peer-reviewed studies from 2000 to November 2022. We selected studies that detected Shigella in stools by culture or polymerase chain reaction (PCR). Two reviewers extracted the data using a standardized form and performed quality assessments using the Joanna Briggs Institute checklist. The random effects model was used to estimate the pooled prevalence of Shigella.
RESULTS
During our search, we identified 4376 studies. 29 studies (from six Southeast Asian countries) were included in the systematic review, 21 each in the meta-analysis of the prevalence of Shigella (Sample size: 109545) and the prevalence of Shigella serogroups. The pooled prevalence of Shigella was 4% (95% CI: 4-5%) among diarrhea cases. Shigella sonnei was the most abundant serogroup in Thailand (74%) and Vietnam (57%), whereas Shigella flexneri was dominant in Indonesia (72%) and Cambodia (71%). Shigella dysenteriae and Shigella boydii were uncommon (pooled prevalence of 1% each). The pooled prevalence of Shigella was 5% (95% CI: 4-6%) in children aged <5 years. The pooled prevalence showed a decreasing trend comparing data collected between 2000-2013 (5%; 95% CI: 4-6%) and between 2014-2022 (3%; 95% CI: 2-4%). Shigella prevalence was 6% in studies that included participants with mixed pathogens versus 3% in those without. Shigella flexneri serotype 2a was the most frequently isolated (33%), followed by 3a (21%), 1b (10%), 2b (3%), and 6 (3%).
CONCLUSIONS
This study provides compelling evidence for the development of effective Shigella vaccines for residents of endemic regions and travellers to these areas.
Topics: Child; Humans; Dysentery, Bacillary; Shigella; Shigella dysenteriae; Shigella flexneri; Indonesia
PubMed: 36792021
DOI: 10.1016/j.tmaid.2023.102554