RESUMEN

Shigella flexneri is a gram-negative bacterium responsible for shigellosis and bacterial dysentery. Despite using various synthetic antimicrobial agents and antibiotics, their efficacy is limited, prompting concerns over antibiotic resistance and associated health risks. This study investigated eugenol, a polyphenol with inherent antioxidant and antibacterial properties, as a potential alternative treatment. We aimed to evaluate eugenol's antibacterial effects and mechanisms of action against S. flexneri and its impact on biofilm formation. We observed significant growth suppression of S. flexneri with eugenol concentrations of 8-10 mM (98.29%). Quantitative analysis using the Crystal Violet assay demonstrated a marked reduction in biofilm formation at 10 mM (97.01 %). Assessment of Cell Viability and morphology via Fluorescence-Activated Cell Sorting and Scanning Electron Microscopy confirmed these findings. Additionally, qPCR analysis revealed the downregulation of key genes responsible for adhesion (yebL), quorum sensing (rcsC, sdiA), and EPS production (s0482) associated with bacterial growth and biofilm formation. The present study suggests eugenol could offer a promising alternative to conventional antibiotics for treating shigellosis caused by S. flexneri.

Asunto(s)

Antibacterianos , Biopelículas , Eugenol , Shigella flexneri , Biopelículas/efectos de los fármacos , Biopelículas/crecimiento & desarrollo , Shigella flexneri/efectos de los fármacos , Shigella flexneri/genética , Shigella flexneri/crecimiento & desarrollo , Shigella flexneri/fisiología , Eugenol/farmacología , Antibacterianos/farmacología , Percepción de Quorum/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Disentería Bacilar/tratamiento farmacológico , Disentería Bacilar/microbiología , Terpenos/farmacología

RESUMEN

BackgroundShigella is a leading cause of moderate-to-severe diarrhoea worldwide and diarrhoeal deaths in children in low- and-middle-income countries.AimWe investigated trends and characteristics of shigellosis and antimicrobial resistance of Shigella sonnei in Israel.MethodsWe analysed data generated by the Sentinel Laboratory-Based Surveillance Network for Enteric Pathogens that systematically collects data on detection of Shigella at sentinel laboratories, along with the characterisation of the isolates at the Shigella National Reference Laboratory. Trends in the shigellosis incidence were assessed using Joinpoint regression and interrupted time-series analyses.ResultsThe average incidence of culture-confirmed shigellosis in Israel declined from 114 per 100,000 population (95% confidence interval (CI): 112-115) 1998-2004 to 80 per 100,000 population (95% CI: 79-82) 2005-2011. This rate remained stable 2012-2019, being 18-32 times higher than that reported from the United States or European high-income countries. After decreasing to its lowest values during the COVID-19 pandemic years (19/100,000 in 2020 and 5/100,000 in 2021), the incidence of culture-confirmed shigellosis increased to 39 per 100,000 population in 2022. Shigella sonnei is the most common serogroup, responsible for a cyclic occurrence of propagated epidemics, and the proportion of Shigella flexneri has decreased. Simultaneous resistance of S. sonnei to ceftriaxone, ampicillin and sulphamethoxazole-trimethoprim increased from 8.5% (34/402) in 2020 to 92.0% (801/876) in 2022.ConclusionsThese findings reinforce the need for continuous laboratory-based surveillance and inform the primary and secondary prevention strategies for shigellosis in Israel and other endemic high-income countries or communities.

Asunto(s)

Antibacterianos , Disentería Bacilar , Vigilancia de Guardia , Shigella sonnei , Humanos , Disentería Bacilar/epidemiología , Disentería Bacilar/microbiología , Disentería Bacilar/diagnóstico , Israel/epidemiología , Niño , Preescolar , Incidencia , Adolescente , Lactante , Masculino , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Femenino , Shigella sonnei/aislamiento & purificación , Shigella sonnei/efectos de los fármacos , Adulto , Persona de Mediana Edad , Adulto Joven , COVID-19/epidemiología , SARS-CoV-2 , Pruebas de Sensibilidad Microbiana , Anciano , Diarrea/epidemiología , Diarrea/microbiología , Recién Nacido , Farmacorresistencia Bacteriana

RESUMEN

BACKGROUND: The purpose of this study was to look into the presence of plasmid-mediated quinolone resistance (PMQR) genes and biofilm formation in several species of clinical Shigella isolates that were resistant to quinolones. METHODS: The stool samples of 150 patients (younger than 10 years) with diarrhea were collected in this cross-sectional study (November 2020 to December 2021). After cultivation of samples on Hektoen Enteric agar and xylose lysine deoxycholate agar, standard microbiology tests, VITEK 2 system, and polymerase chain reaction (PCR) were utilized to identify Shigella isolates. The broth microdilution method was used to determine antibiotic susceptibility. PMQR genes including qnrA, qnrB, qnrC, qnrD, qnrE, qnrS, qnrVC, qepA, oqxAB, aac(6')-Ib-cr, and crpP and biofilm formation were investigated in quinolone-resistant isolates by PCR and microtiter plate method, respectively. An enterobacterial repetitive intergenic consensus polymerase chain reaction (ERIC-PCR) technique was used to determine the clonal relatedness of quinolone-resistant isolates. RESULTS: A total of 95 Shigella isolates including S. sonnei (53, 55.8%), S. flexneri (39, 41.1%), and S. boydii (3, 3.2%) were identified. The highest resistance rates of the isolates were against ampicillin (92.6%, n = 88/95). Overall, 42 of 95 (44.2%) isolates were simultaneously resistant against two or more quinolones including 26 (61.9%) S. sonnei and 16 (38.1%) S. flexneri. All isolates were multidrug-resistant (resistance to more than 3 antibiotics). The occurrence of PMQR genes was as follows: qnrS (52.4%), qnrA and aac(6')-Ib-cr (33.3%), and qnrB (19.0%). The prevalence in species was as follows: 61.5% and 37.5% (qnrS), 19.2% and 56.3% (qnrA), 38.5% and 25.0 (aac(6')-Ib-cr), and 19.2% and 18.8% (qnrB) for S. sonnei and S. flexneri, respectively. The other PMQR genes were not detected. In total, 52.8% (28/53) of quinolone-susceptible and 64.3% (27/42) of quinolone-resistant isolates were biofilm producers. Biofilm formation was not significantly different between quinolone-resistant and quinolone-susceptible isolates (P-value = 0.299). Quinolone-resistant isolates showed a high genetic diversity according to the ERIC-PCR. CONCLUSION: It seems that qnrS, qnrA, and aac(6')-Ib-cr play a significant role in the quinolone resistance among Shigella isolates in our region. Also the quinolone-resistant S. flexneri and S. sonnei isolates had a high genetic diversity. Hence, antibiotic therapy needs to be routinely revised based on the surveillance findings.

Asunto(s)

Antibacterianos , Biopelículas , Pruebas de Sensibilidad Microbiana , Plásmidos , Quinolonas , Shigella , Humanos , Biopelículas/efectos de los fármacos , Biopelículas/crecimiento & desarrollo , Estudios Transversales , Quinolonas/farmacología , Shigella/genética , Shigella/efectos de los fármacos , Shigella/aislamiento & purificación , Plásmidos/genética , Antibacterianos/farmacología , Farmacorresistencia Bacteriana/genética , Prevalencia , Disentería Bacilar/microbiología , Disentería Bacilar/epidemiología , Disentería Bacilar/tratamiento farmacológico , Femenino

RESUMEN

Shigella bacteria utilize the type III secretion system (T3SS) to invade host cells and establish local infection. Invasion plasmid antigen D (IpaD), a component of Shigella T3SS, has garnered extensive interest as a vaccine target, primarily due to its pivotal role in the Shigella invasion, immunogenic property, and a high degree of conservation across Shigella species and serotypes. Currently, we are developing an epitope- and structure-based multivalent vaccine against shigellosis and require functional epitope antigens of key Shigella virulence determinants including IpaD. However, individual IpaD B-cell epitopes, their contributions to the overall immunogenicity, and functional activities attributing to bacteria invasion have not been fully characterized. In this study, we predicted continuous B-cell epitopes in silico and fused each epitope to a carrier protein. Then, we immunized mice intramuscularly with each epitope fusion protein, examined the IpaD-specific antibody responses, and measured antibodies from each epitope fusion for the activity against Shigella invasion in vitro. Data showed that all epitope fusion proteins induced similar levels of anti-IpaD IgG antibodies in mice, and differences were noted for antibody inhibition activity against Shigella invasion. IpaD epitope 1 (SPGGNDGNSV), IpaD epitope 2 (LGGNGEVVLDNA), and IpaD epitope 5 (SPNNTNGSSTET) induced antibodies significantly better in inhibiting invasion from Shigella flexneri 2a, and epitopes 1 and 5 elicited antibodies more effectively at preventing invasion of Shigella sonnei. These results suggest that IpaD epitopes 1 and 5 can be the IpaD representative antigens for epitope-based polyvalent protein construction and protein-based cross-protective Shigella vaccine development.IMPORTANCEShigella is a leading cause of diarrhea in children younger than 5 years in developing countries (children's diarrhea) and continues to be a major threat to public health. No licensed vaccines are currently available against the heterogeneous Shigella species and serotype strains. Aiming to develop a cross-protective multivalent vaccine against shigellosis and dysentery, we applied novel multiepitope fusion antigen (MEFA) technology to construct a broadly immunogenic polyvalent protein antigen, by presenting functional epitopes of multiple Shigella virulence determinants on a backbone protein. The functional IpaD epitopes identified from this study will essentially allow us to construct an optimal polyvalent Shigella immunogen, leading to the development of a cross-protective vaccine against shigellosis (and dysentery) and the improvement of global health. In addition, identifying functional epitopes from heterogeneous virulence determinants and using them as antigenic representatives for the development of cross-protective multivalent vaccines can be applied generally in vaccine development.

Asunto(s)

Antígenos Bacterianos , Epítopos de Linfocito B , Shigella flexneri , Antígenos Bacterianos/inmunología , Antígenos Bacterianos/genética , Animales , Ratones , Shigella flexneri/inmunología , Shigella flexneri/genética , Epítopos de Linfocito B/inmunología , Vacunas contra la Shigella/inmunología , Vacunas contra la Shigella/administración & dosificación , Vacunas contra la Shigella/genética , Disentería Bacilar/prevención & control , Disentería Bacilar/inmunología , Disentería Bacilar/microbiología , Ratones Endogámicos BALB C , Mapeo Epitopo , Femenino , Shigella/inmunología , Shigella/genética , Proteínas Bacterianas/inmunología , Proteínas Bacterianas/genética , Anticuerpos Antibacterianos/inmunología , Anticuerpos Antibacterianos/sangre , Shigella sonnei/inmunología , Shigella sonnei/genética , Sistemas de Secreción Tipo III/inmunología , Sistemas de Secreción Tipo III/genética

RESUMEN

Background: The method currently available to diagnose shigellosis is insensitive and has many limitations. Thus, this study was designed to identify specific antigenic protein(s) among the cell surface associated proteins (SAPs) of Shigella that would be valuable in the development of an alternative diagnostic assay for shigellosis, particularly one that could be run using a stool sample rather than serum. Methods: The SAPs of clinical isolates of S. dysenteriae, S. boydii, Shigella flexneri, and S. sonnei were extracted from an overnight culture grown at 37 °C using acidified-glycine extraction methods. Protein profiles were observed by SDS-PAGE. To determine if antibodies specific to certain Shigella SAPs were present in both sera and stool suspensions, Western blot analysis was used to detect the presence of IgA, IgG, and IgM. Results: Immunoblot analysis revealed that sera from patients infected with S. flexneri recognized 31 proteins. These SAP antigens are recognized by the host humoral response during Shigella infection. Specific antibodies against these antigens were also observed in intestinal secretions of shigellosis patients. Of these 31 S. flexneri proteins, the 35 kDa protein specifically reacted against IgA present in patients' stool suspensions. Further study illustrated the immunoreactivity of this protein in S. dysenteriae, S. boydii, and S. sonnei. This is the first report that demonstrates the presence of immunoreactive Shigella SAPs in stool suspensions. The SAPSs could be very useful in developing a simple and rapid serodiagnostic assay for shigellosis directly from stool specimens.

Asunto(s)

Proteínas Bacterianas , Disentería Bacilar , Heces , Shigella flexneri , Humanos , Heces/microbiología , Heces/química , Disentería Bacilar/diagnóstico , Disentería Bacilar/inmunología , Disentería Bacilar/microbiología , Shigella flexneri/inmunología , Shigella flexneri/aislamiento & purificación , Proteínas Bacterianas/inmunología , Proteínas Bacterianas/análisis , Anticuerpos Antibacterianos/sangre , Anticuerpos Antibacterianos/inmunología , Antígenos Bacterianos/inmunología , Antígenos Bacterianos/análisis , Western Blotting , Electroforesis en Gel de Poliacrilamida , Inmunoglobulina A/inmunología , Inmunoglobulina A/sangre , Inmunoglobulina A/análisis

RESUMEN

Vinculin is a cytoskeletal linker strengthening cell adhesion. The Shigella IpaA invasion effector binds to vinculin to promote vinculin supra-activation associated with head-domain-mediated oligomerization. Our study investigates the impact of mutations of vinculin D1D2 subdomains' residues predicted to interact with IpaA VBS3. These mutations affected the rate of D1D2 trimer formation with distinct effects on monomer disappearance, consistent with structural modeling of a closed and open D1D2 conformer induced by IpaA. Notably, mutations targeting the closed D1D2 conformer significantly reduced Shigella invasion of host cells as opposed to mutations targeting the open D1D2 conformer and later stages of vinculin head-domain oligomerization. In contrast, all mutations affected the formation of focal adhesions (FAs), supporting the involvement of vinculin supra-activation in this process. Our findings suggest that IpaA-induced vinculin supra-activation primarily reinforces matrix adhesion in infected cells, rather than promoting bacterial invasion. Consistently, shear stress studies pointed to a key role for IpaA-induced vinculin supra-activation in accelerating and strengthening cell-matrix adhesion.

Asunto(s)

Adhesión Celular , Adhesiones Focales , Vinculina , Vinculina/metabolismo , Vinculina/genética , Humanos , Adhesiones Focales/metabolismo , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Mutación , Interacciones Huésped-Patógeno , Células HeLa , Unión Proteica , Shigella/metabolismo , Shigella/genética , Antígenos Bacterianos/metabolismo , Antígenos Bacterianos/genética , Disentería Bacilar/microbiología , Disentería Bacilar/metabolismo

RESUMEN

Shigellosis, induced by Shigella flexneri, constitutes a significant health burden in developing nations, particularly impacting socioeconomically disadvantaged communities. Designated as the second most prevalent cause of diarrheal illness by the World Health Organization (WHO), it precipitates an estimated 212,000 fatalities annually. Within the spectrum of S. flexneri strains, serotype X is notably pervasive and resilient, yet its comprehensive characterization remains deficient. The present investigation endeavors to discern potential pharmacological targets and repurpose existing drug compounds against S. flexneri serotype X. Employing the framework of subtractive genomics, the study interrogates the reference genome of S. flexneri Serotype X (strain 2,002,017; UP000001884) to delineate its proteome into categories of non-homologous, non-paralogous, essential, virulent, and resistant constituents, thereby facilitating the identification of therapeutic targets. Subsequently, a screening of approximately 9000 compounds from the FDA library against the identified drug target aims to delineate efficacious agents for combating S. flexneri serotype X infections. The application of subtractive genomics methodology yields prognostic insights, unveiling non-paralogous proteins (n = 4122), non-homologues (n = 1803), essential (n = 1246), drug-like (n = 389), resistant (n = 167), alongside 42 virulent proteins within the reference proteome. This iterative process culminates in the identification of Serine O-acetyltransferase as a viable drug target. Subsequent virtual screening endeavors to unearth FDA-approved medicinal compounds capable of inhibiting Serine O-acetyltransferase. Noteworthy candidates such as DB12983, DB15085, DB16098, DB16185, and DB16262 emerge, exhibiting potential for mitigating S. flexneri Serotype X. Despite the auspicious findings, diligent scrutiny is imperative to ascertain the efficacy and safety profile of the proposed drug candidates vis-à-vis S. flexneri.

Asunto(s)

Antibacterianos , Reposicionamiento de Medicamentos , Disentería Bacilar , Genómica , Serogrupo , Shigella flexneri , Shigella flexneri/efectos de los fármacos , Shigella flexneri/genética , Reposicionamiento de Medicamentos/métodos , Genómica/métodos , Antibacterianos/farmacología , Disentería Bacilar/tratamiento farmacológico , Disentería Bacilar/microbiología , Humanos , Genoma Bacteriano , Simulación por Computador , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo

RESUMEN

Shigella dysenteriae, is a Gram-negative bacterium that emerged as the second most significant cause of bacillary dysentery. Antibiotic treatment is vital in lowering Shigella infection rates, yet the growing global resistance to broad-spectrum antibiotics poses a significant challenge. The persistent multidrug resistance of S. dysenteriae complicates its management and control. Hence, there is an urgent requirement to discover novel therapeutic targets and potent medications to prevent and treat this disease. Therefore, the integration of bioinformatics methods such as subtractive and comparative analysis provides a pathway to compute the pan-genome of S. dysenteriae. In our study, we analysed a dataset comprising 27 whole genomes. The S. dysenteriae strain SD197 was used as the reference for determining the core genome. Initially, our focus was directed towards the identification of the proteome of the core genome. Moreover, several filters were applied to the core genome, including assessments for non-host homology, protein essentiality, and virulence, in order to prioritize potential drug targets. Among these targets were Integration host factor subunit alpha and Tyrosine recombinase XerC. Furthermore, four drug-like compounds showing potential inhibitory effects against both target proteins were identified. Subsequently, molecular docking analysis was conducted involving these targets and the compounds. This initial study provides the list of novel targets against S. dysenteriae. Conclusively, future in vitro investigations could validate our in-silico findings and uncover potential therapeutic drugs for combating bacillary dysentery infection.

Asunto(s)

Antibacterianos , Simulación por Computador , Disentería Bacilar , Simulación del Acoplamiento Molecular , Shigella dysenteriae , Shigella dysenteriae/efectos de los fármacos , Shigella dysenteriae/genética , Shigella dysenteriae/patogenicidad , Humanos , Antibacterianos/farmacología , Disentería Bacilar/microbiología , Disentería Bacilar/tratamiento farmacológico , Genoma Bacteriano , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Biología Computacional/métodos

Asunto(s)

Septinas , Septinas/metabolismo , Septinas/genética , Humanos , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Shigella/patogenicidad , Shigella/metabolismo , Disentería Bacilar/microbiología

RESUMEN

We meta-analyzed the diagnostic accuracy of rapid diagnostic tests (dipsticks) and loop-mediated isothermal amplification (LAMP) method to detect Shigella species. We searched MEDLINE, Embase, Web of Science and Google Scholar from inception to 2023 for studies reporting on the performance of Shigella dipstick and LAMP tests compared with culture or polymerase chain reaction (PCR). Our search identified 2618 studies, of which fourteen met the inclusion criteria for the systematic review. Ten studies covering 4056 tests (from twelve countries) were included in the meta-analysis. The overall pooled sensitivity and specificity were 98% (95% CI: 94-100) and 97% (95% CI: 92-99), respectively. Pooled sensitivity and specificity of dipsticks were 95% and 98%, respectively. In contrast, LAMP showed higher pooled sensitivity (100%) and diagnostic odds ratio (431752), but similar specificity (97%). LAMP and dipstick tests exhibited promising performance, suggesting that they could be useful for assisting in the diagnosis of shigellosis.

Asunto(s)

Disentería Bacilar , Técnicas de Diagnóstico Molecular , Técnicas de Amplificación de Ácido Nucleico , Sensibilidad y Especificidad , Shigella , Humanos , Técnicas de Amplificación de Ácido Nucleico/métodos , Shigella/aislamiento & purificación , Shigella/genética , Disentería Bacilar/diagnóstico , Disentería Bacilar/microbiología , Técnicas de Diagnóstico Molecular/métodos , Pruebas Diagnósticas de Rutina/métodos , Prueba de Diagnóstico Rápido

RESUMEN

Shigella spp. are Gram-negative gastrointestinal bacterial pathogens that cause bacillary dysentery or shigellosis in humans. Isolation of Shigella from outbreak-associated foods is often problematic due to the lack of selectivity of cultural enrichment broths. To facilitate Shigella recovery from foods, we have developed strain-specific enrichment media based on the genomically-predicted antimicrobial resistance (AMR) features of an outbreak-associated Shigella sonnei strain harboring resistance genes for streptomycin (STR) and trimethoprim (TMP). To assess performance of the method, baby carrots were artificially contaminated with the S. sonnei strain at low (2.4 CFU), medium (23.5 CFU), and high levels (235 CFU) along with 10-fold higher levels of a Shigella-inhibiting Escherichia coli strain. The target S. sonnei strain was successfully recovered from artificially-contaminated baby carrots when enriched in modified Tryptone Soya Broth (mTSB) supplemented with TMP, whereas Shigella was not recovered from Shigella broth (SB) or SB supplemented with STR. Quantitative PCR analysis indicated that supplementation of the enrichment broths with TMP or STR increased the relative proportion of S. sonnei in enrichment cultures, except at the lowest inoculation level for STR. Microbiome profiling of the baby carrot enrichment cultures conducted by 16S rRNA gene sequencing indicated that both SB-STR and mTSB-TMP repressed the growth of competing Enterobacteriaceae in the enrichment cultures, relative to SB without supplementation. Overall, improved Shigella recovery was achieved with the addition of the appropriate custom selective agent during cultural enrichments demonstrating that genomically informed custom selective enrichment of Shigella could be a valuable tool for supporting future foodborne shigellosis outbreak investigations.

Asunto(s)

Daucus carota , Microbiología de Alimentos , Shigella sonnei , Humanos , Shigella sonnei/efectos de los fármacos , Shigella sonnei/genética , Daucus carota/microbiología , Antibacterianos/farmacología , Inocuidad de los Alimentos , Shigella/efectos de los fármacos , Shigella/genética , Disentería Bacilar/microbiología , Farmacorresistencia Bacteriana , Farmacorresistencia Microbiana , Contaminación de Alimentos/análisis

RESUMEN

BACKGROUND: Diarrhea caused by Salmonella and Shigella species are the leading cause of illness especially in developing countries. These infections are considered as the main public health problems in children, including Ethiopia. This study aimed to assess the prevalence, associated factors, and antimicrobial susceptibility patterns of Salmonella and Shigella species in Sheik Hassan Yabere Referral Hospital Jigjiga, Eastern Ethiopia from August 05 to November 15, 2022. METHOD: A cross-sectional study was conducted among 239 under-five children with diarrhea selected through a convenient sampling technique. A structured questionnaire was used to collect associated factors. A stool sample was collected and processed for the identification of Salmonella and Shigella species using MacConkey adar, Xylose Lysine Deoxycholate agar (Oxoid Ltd) and Biochemical tests. The antimicrobial susceptibility pattern of isolates was performed using the Kirby-Bauer disc diffusion technique. The data was entered into Epi-data version 4.6 and exported to the statistical package of social science version 22 for analysis. The association between outcome and independent variables was assessed using bivariate, multivariable, and chi-square and P-value < 0.05 was considered as statistical significance. RESULT: Overall prevalence of Salmonella and Shigella species was 6.3% (95% CI, 5.7-6.9%), of which 3.8% (95 CI, 3.2-4.4%) were Salmonella species and 2.5% (95% CI, 1.95-3%) were Shigella species. Unimproved water source (AOR = 5.08, 95% CI = 1.45, 17.25), open field (AOR = 2.3, 95% CI = 1.3, 5.03), rural residence (AOR = 1.8, 95% CI = 1.4, 7.5), Hand-washing practice (p = 0.001), and raw meat consumption (p = 0.002) were associated with occurrence of Salmonella and Shigella species. Salmonella and Shigella isolates were resistant to Ampicilin (100%). However, Salmonella isolates was sensitive to Norfloxacin (100%). About 22.2% and 16.7% of Salmonella and Shigella isolates were multi-drug resistant, respectively. CONCLUSION: Prevalence of Salmonella and Shigella species were lower than most studies done in Ethiopia. Hand-washing habit, water source type, Open field waste disposal habit, raw meat consumption and rural residence were associated with Salmonellosis and shigellosis. All isolated Salmonella were sensitive to norfloxacin. The evidence from this study underscores the need for improved water, sanitation and hygiene (WASH) system and the imperative to implement drug susceptibility tests for the treatment of Salmonella and Shigella infection.

Asunto(s)

Diarrea , Disentería Bacilar , Pruebas de Sensibilidad Microbiana , Salmonella , Shigella , Humanos , Etiopía/epidemiología , Estudios Transversales , Preescolar , Femenino , Salmonella/aislamiento & purificación , Salmonella/efectos de los fármacos , Masculino , Prevalencia , Shigella/efectos de los fármacos , Shigella/aislamiento & purificación , Lactante , Diarrea/microbiología , Diarrea/epidemiología , Disentería Bacilar/epidemiología , Disentería Bacilar/microbiología , Disentería Bacilar/tratamiento farmacológico , Infecciones por Salmonella/epidemiología , Infecciones por Salmonella/microbiología , Infecciones por Salmonella/tratamiento farmacológico , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Factores de Riesgo , Heces/microbiología , Farmacorresistencia Bacteriana

RESUMEN

Shigella flexneri is a Gram-negative bacterium causing severe bloody dysentery. Its pathogenesis is largely dictated by a plasmid-encoded type III secretion system (T3SS) and its associated effectors. Among these, the effector OspG has been shown to bind to the ubiquitin conjugation machinery (E2~Ub) to activate its kinase activity. However, the cellular targets of OspG remain elusive despite years of extensive efforts. Here we show by unbiased phosphoproteomics that a major target of OspG is CAND1, a regulatory protein controlling the assembly of cullin-RING ubiquitin ligases (CRLs). CAND1 phosphorylation weakens its interaction with cullins, which is expected to impact a large panel of CRL E3s. Indeed, global ubiquitome profiling reveals marked changes in the ubiquitination landscape when OspG is introduced. Notably, OspG promotes ubiquitination of a class of cytoskeletal proteins called septins, thereby inhibiting formation of cage-like structures encircling cytosolic bacteria. Overall, we demonstrate that pathogens have evolved an elaborate strategy to modulate host ubiquitin signaling to evade septin-cage entrapment.

Asunto(s)

Proteínas Bacterianas , Septinas , Shigella flexneri , Transducción de Señal , Ubiquitina , Ubiquitinación , Shigella flexneri/metabolismo , Shigella flexneri/patogenicidad , Septinas/metabolismo , Septinas/genética , Humanos , Ubiquitina/metabolismo , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Fosforilación , Interacciones Huésped-Patógeno , Células HeLa , Proteínas Cullin/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitina-Proteína Ligasas/genética , Células HEK293 , Disentería Bacilar/microbiología , Disentería Bacilar/metabolismo

RESUMEN

Introduction: Shigella is the etiologic agent of a bacillary dysentery known as shigellosis, which causes millions of infections and thousands of deaths worldwide each year due to Shigella's unique lifestyle within intestinal epithelial cells. Cell adhesion/invasion assays have been extensively used not only to identify targets mediating host-pathogen interaction, but also to evaluate the ability of Shigella-specific antibodies to reduce virulence. However, these assays are time-consuming and labor-intensive and fail to assess differences at the single-cell level. Objectives and methods: Here, we developed a simple, fast and high-content method named visual Adhesion/Invasion Inhibition Assay (vAIA) to measure the ability of anti-Shigellaantibodies to inhibit bacterial adhesion to and invasion of epithelial cells by using the confocal microscope Opera Phenix. Results: We showed that vAIA performed well with a pooled human serum from subjects challenged with S. sonnei and that a specific anti-IpaD monoclonal antibody effectively reduced bacterial virulence in a dose-dependent manner. Discussion: vAIA can therefore inform on the functionality of polyclonal and monoclonal responses thereby supporting the discovery of pathogenicity mechanisms and the development of candidate vaccines and immunotherapies. Lastly, this assay is very versatile and may be easily applied to other Shigella species or serotypes and to different pathogens.

Asunto(s)

Anticuerpos Antibacterianos , Adhesión Bacteriana , Disentería Bacilar , Humanos , Adhesión Bacteriana/inmunología , Disentería Bacilar/inmunología , Disentería Bacilar/microbiología , Disentería Bacilar/diagnóstico , Anticuerpos Antibacterianos/inmunología , Interacciones Huésped-Patógeno/inmunología , Shigella/inmunología , Shigella/patogenicidad , Células Epiteliales/microbiología , Células Epiteliales/inmunología , Shigella sonnei/inmunología , Anticuerpos Monoclonales/inmunología , Anticuerpos Monoclonales/farmacología , Células HeLa

RESUMEN

The urgent need for comprehensive and systematic analyses of Shigella as the key pathogen led us to meticulously explore the epidemiology and molecular attributes of Shigella isolates. Accordingly, we procured 24 isolates (10 from Xinjiang and 14 from Wuhan, China) and performed serotype identification and antimicrobial susceptibility testing. Resistance gene detection and homology analysis by polymerase chain reaction and pulsed-field gel electrophoresis (PFGE), respectively, were performed for genetic diversity analysis. All isolates were identified as Shigella flexneri, with 70% (35.4-91.9%) and 30% (8.1-64.6%) of the Xinjiang isolates and 85.7% (56.2-97.5%) and 14.3% (2/14, 2.5-43.9%) of the Wuhan isolates belonging to serotype 2a and serotype 2b, respectively. All isolates displayed resistance to at least two antibiotics and complete resistance to ampicillin. Multidrug resistance (MDR) was recorded in 70.8% (48.8-86.6%) of isolates, with Xinjiang isolates exhibiting relatively higher resistance to ampicillin-sulbactam, piperacillin, ceftriaxone, and aztreonam. Conversely, Wuhan isolates displayed higher MDR and resistance to tetracycline, ciprofloxacin, levofloxacin, and cefepime relative to Xinjiang isolates. Molecular scrutiny of antibiotic-resistance determinants revealed that blaTEM was the main mechanism of ampicillin resistance, blaCTX-M was the main gene for resistance to third- and fourth-generation cephalosporins, and tetB was the predominant gene associated with tetracycline resistance. Four Xinjiang and seven Wuhan isolates shared T1-clone types (>85%), and two Xinjiang and one Wuhan isolates were derived from the T6 clone with a high similarity of 87%. Six PFGE patterns (T1, T2, T5, T6-3, T8, and T10) of S. flexneri were associated with MDR. Thus, there is a critical need for robust surveillance and control strategies in managing Shigella infections, along with the development of targeted interventions and antimicrobial stewardship programs tailored to the distinct characteristics of Shigella isolates in different regions of China.

Asunto(s)

Antibacterianos , Farmacorresistencia Bacteriana Múltiple , Disentería Bacilar , Electroforesis en Gel de Campo Pulsado , Variación Genética , Pruebas de Sensibilidad Microbiana , Shigella flexneri , China/epidemiología , Antibacterianos/farmacología , Humanos , Disentería Bacilar/microbiología , Disentería Bacilar/epidemiología , Farmacorresistencia Bacteriana Múltiple/genética , Shigella flexneri/efectos de los fármacos , Shigella flexneri/genética , Shigella flexneri/aislamiento & purificación , Shigella flexneri/clasificación , Shigella/genética , Shigella/efectos de los fármacos , Shigella/aislamiento & purificación , Shigella/clasificación , Serogrupo , Reacción en Cadena de la Polimerasa

RESUMEN

We report the detection of OXA-181 carbapenemase in an azithromycin-resistant Shigella spp. bacteria in an immunocompromised patient. The emergence of OXA-181 in Shigella spp. bacteria raises concerns about the global dissemination of carbapenem resistance in Enterobacterales and its implications for the treatment of infections caused by Shigella bacteria.

Asunto(s)

Antibacterianos , Proteínas Bacterianas , Disentería Bacilar , Pruebas de Sensibilidad Microbiana , Shigella flexneri , beta-Lactamasas , Shigella flexneri/efectos de los fármacos , Shigella flexneri/aislamiento & purificación , Shigella flexneri/enzimología , Shigella flexneri/genética , Humanos , beta-Lactamasas/genética , beta-Lactamasas/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Disentería Bacilar/microbiología , Disentería Bacilar/diagnóstico , Disentería Bacilar/tratamiento farmacológico , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Masculino , Huésped Inmunocomprometido , Farmacorresistencia Bacteriana , Azitromicina/farmacología , Azitromicina/uso terapéutico

RESUMEN

Shigella stands as a major contributor to bacterial dysentery worldwide scale, particularly in developing countries with inadequate sanitation and hygiene. The emergence of multidrug-resistant strains exacerbates the challenge of treating Shigella infections, particularly in regions where access to healthcare and alternative antibiotics is limited. Therefore, investigations on how bacteria evade antibiotics and eventually develop resistance could open new avenues for research to develop novel therapeutics. The aim of this study was to analyze whole genome sequence (WGS) of human pathogenic Shigella spp. to elucidate the antibiotic resistance genes (ARGs) and their mechanism of resistance, gene-drug interactions, protein-protein interactions, and functional pathways to screen potential therapeutic candidate(s). We comprehensively analyzed 45 WGS of Shigella, including S. flexneri (n = 17), S. dysenteriae (n = 14), S. boydii (n = 11), and S. sonnei (n = 13), through different bioinformatics tools. Evolutionary phylogenetic analysis showed three distinct clades among the circulating strains of Shigella worldwide, with less genomic diversity. In this study, 2,146 ARGs were predicted in 45 genomes (average 47.69 ARGs/genome), of which only 91 ARGs were found to be shared across the genomes. Majority of these ARGs conferred their resistance through antibiotic efflux pump (51.0%) followed by antibiotic target alteration (23%) and antibiotic target replacement (18%). We identified 13 hub proteins, of which four proteins (e.g., tolC, acrR, mdtA, and gyrA) were detected as potential hub proteins to be associated with antibiotic efflux pump and target alteration mechanisms. These hub proteins were significantly (p < 0.05) enriched in biological process, molecular function, and cellular components. Therefore, the finding of this study suggests that human pathogenic Shigella strains harbored a wide range of ARGs that confer resistance through antibiotic efflux pumps and antibiotic target modification mechanisms, which must be taken into account to devise and formulate treatment strategy against this pathogen. Moreover, the identified hub proteins could be exploited to design and develop novel therapeutics against MDR pathogens like Shigella.

Asunto(s)

Disentería Bacilar , Shigella , Humanos , Filogenia , Farmacorresistencia Bacteriana/genética , Pruebas de Sensibilidad Microbiana , Shigella/genética , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Disentería Bacilar/tratamiento farmacológico , Disentería Bacilar/genética , Disentería Bacilar/microbiología , Shigella flexneri

RESUMEN

Shigella is an important human-adapted pathogen which contributes to a large global burden of diarrhoeal disease. Together with the increasing threat of antimicrobial resistance and lack of an effective vaccine, there is great urgency to identify novel therapeutics and preventatives to combat Shigella infection. In this review, we discuss the development of innovative technologies and animal models to study mechanisms underlying Shigella infection of humans. We examine recent literature introducing (i) the organ-on-chip model, and its substantial contribution towards understanding the biomechanics of Shigella infection, (ii) the zebrafish infection model, which has delivered transformative insights into the epidemiological success of clinical isolates and the innate immune response to Shigella, (iii) a pioneering oral mouse model of shigellosis, which has helped to discover new inflammasome biology and protective mechanisms against shigellosis, and (iv) the controlled human infection model, which has been effective in translating basic research into human health impact and assessing suitability of novel vaccine candidates. We consider the recent contributions of each model and discuss where the future of modelling Shigella infection lies.

Asunto(s)

Modelos Animales de Enfermedad , Disentería Bacilar , Shigella , Pez Cebra , Disentería Bacilar/microbiología , Disentería Bacilar/inmunología , Animales , Humanos , Shigella/patogenicidad , Shigella/inmunología , Pez Cebra/microbiología , Ratones , Inmunidad Innata , Inflamasomas/inmunología , Vacunas contra la Shigella/inmunología , Vacunas contra la Shigella/administración & dosificación

RESUMEN

Antimicrobial agents are essential in reducing illness and mortality brought on by infectious diseases in both humans and animals. However, the therapeutic effect of antibiotics has diminished due to an increase in antimicrobial drug resistance (AMR). This article provides a retrospective analysis of AMR in Shigella infections in India, showing a rise in resistance that has contributed to a global burden. Shigella spp. are widespread and the second-leading cause of diarrheal death in people of all ages. The frequency and mortality rates of Shigella infections are decreased by antibiotic treatment. However, the growth of broad-spectrum antibiotic resistance is making it more difficult to treat many illnesses. Reduced cell permeability, efflux pumps, and the presence of enzymes that break down antibiotics are the causes of resistance. AMR is a multifaceted and cross-sectoral problem that affects humans, animals, food, and the environment. As a result, there is a growing need for new therapeutic approaches, and ongoing surveillance of Shigella spp. infections which should definitely be improved for disease prevention and management. This review emphasizes on the epidemiological data of India, and antimicrobial resistance in Shigella spp.

Asunto(s)

Antibacterianos , Farmacorresistencia Bacteriana , Disentería Bacilar , Shigella , Humanos , India/epidemiología , Shigella/efectos de los fármacos , Disentería Bacilar/tratamiento farmacológico , Disentería Bacilar/epidemiología , Disentería Bacilar/microbiología , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Farmacorresistencia Bacteriana/efectos de los fármacos , Animales

RESUMEN

Shigellosis is spread through the fecal-oral route, including sexual activity. The Centers for Disease Control and Prevention recommends collecting a sexual history from people diagnosed with shigellosis to enhance the understanding of its epidemiology and outbreak detection and the design of disease prevention messaging, although individual jurisdictions decide if and how this is done. Moreover, enteric disease interviewers typically receive in-depth general interviewing training, but often not sexual history question training. The goal of this project was to inform national practices around sexual history questions asked during shigellosis interviews by collecting information from U.S. state health agencies and evaluating sexual history data from people diagnosed with shigellosis in Colorado. From November 2021 to January 2022, information on sexual history questions asked of persons with reported shigellosis and accompanying training resources were collected from U.S. state health departments. Data completeness and quality of shigellosis sexual history questions from Colorado's notifiable disease database from 2018 to 2022 were also evaluated. Of 48 states, 54% reported routinely asking all adults about their sexual history during shigellosis interviews. Of 44 states, 18% indicated having accompanying training materials for interviewers. In Colorado, the proportion of unknown/missing responses to questions about recent sexual contact with male and female partners was lower for males (3.3% unknown and 3.3% missing) than females (5.4% and 6.2%) and highest among those 66 years and older (6.7% and 10%). Among those reporting new sexual partners, 93.5% indicated how they met. The evaluation of Colorado data demonstrates that routine collection of complete, high-quality, actionable sexual history data from all adults with reported shigellosis is feasible. Nearly half of the responding states indicated not doing so, and few had training resources. We recommend training enteric disease interviewers to routinely ask all adults with reported shigellosis about their sexual history, including new partner meeting location.

Asunto(s)

Disentería Bacilar , Humanos , Disentería Bacilar/epidemiología , Disentería Bacilar/microbiología , Femenino , Masculino , Adulto , Colorado/epidemiología , Estados Unidos/epidemiología , Persona de Mediana Edad , Conducta Sexual , Exactitud de los Datos , Adulto Joven , Anciano , Adolescente , Brotes de Enfermedades , Centers for Disease Control and Prevention, U.S.