Tyrosine-modifying glycosylation by Yersinia effectors.

Mono-O-glycosylation of target proteins by bacterial toxins or effector proteins is a well-known mechanism by which bacteria interfere with essential functions of host cells. The respective glycosyltransferases are important virulence factors such as the Clostridioides difficile toxins A and B. Here, we describe two glycosyltransferases of Yersinia species that have a high sequence identity: YeGT from the zoonotic pathogen Yersinia enterocolitica and YkGT from the murine pathogen Yersinia kristensenii. We show that both modify Rho family proteins by attachment of GlcNAc at tyrosine residues (Tyr-34 in RhoA). Notably, the enzymes differed in their target protein specificity. While YeGT modified RhoA, B, and C, YkGT possessed a broader substrate spectrum and glycosylated not only Rho but also Rac and Cdc42 subfamily proteins. Mutagenesis studies indicated that residue 177 is important for this broader target spectrum. We determined the crystal structure of YeGT shortened by 16 residues N terminally (sYeGT) in the ligand-free state and bound to UDP, the product of substrate hydrolysis. The structure assigns sYeGT to the GT-A family. It shares high structural similarity to glycosyltransferase domains from toxins. We also demonstrated that the 16 most N-terminal residues of YeGT and YkGT are important for the mediated translocation into the host cell using the pore-forming protective antigen of anthrax toxin. Mediated introduction into HeLa cells or ectopic expression of YeGT and YkGT caused morphological changes and redistribution of the actin cytoskeleton. The data suggest that YeGT and YkGT are likely bacterial effectors belonging to the family of tyrosine glycosylating bacterial glycosyltransferases.

Development and implementation of a core genome multilocus sequence typing scheme for Yersinia enterocolitica: a tool for surveillance and outbreak detection.

Yersinia enterocolitica (Y. enterocolitica) is the most frequent etiological agent of yersiniosis and has been responsible for several national outbreaks in Norway and elsewhere. A standardized high-resolution method, such as core genome Multilocus Sequence Typing (cgMLST), is needed for pathogen traceability at the national and international levels. In this study, we developed and implemented a cgMLST scheme for Y. enterocolitica. We designed a cgMLST scheme in SeqSphere + using high-quality genomes from different Y. enterocolitica biotype sublineages. The scheme was validated if more than 95% of targets were found across all tested Y. enterocolitica: 563 Norwegian genomes collected between 2012 and 2022 and 327 genomes from public data sets. We applied the scheme to known outbreaks to establish a threshold for identifying major complex types (CTs) based on the number of allelic differences. The final cgMLST scheme included 2,582 genes with a median of 97.9% (interquartile range 97.6%-98.8%) targets found across all tested genomes. Analysis of outbreaks identified all outbreak strains using single linkage clustering at four allelic differences. This threshold identified 311 unique CTs in Norway, of which CT18, CT12, and CT5 were identified as the most frequently associated with outbreaks. The cgMLST scheme showed a very good performance in typing Y. enterocolitica using diverse data sources and was able to identify outbreak clusters. We recommend the implementation of this scheme nationally and internationally to facilitate Y. enterocolitica surveillance and improve outbreak response in national and cross-border outbreaks.

Cold-tolerance mechanisms in foodborne pathogens: Escherichia coli and Listeria monocytogenes as examples.

The cold chain is an integral part of the modern food industry. Low temperatures can effectively alleviate food loss and the transmission of foodborne diseases caused by microbial reproduction. However, recent reports have highlighted shortcomings in the current cold chain technology's ability to prevent and control cold-tolerant foodborne pathogens. Furthermore, it has been observed that certain cold-chain foods have emerged as new sources of infection for foodborne disease outbreaks. Consequently, there is a pressing need to enhance control measures targeting cold-tolerant pathogens within the existing cold chain system. This paper aims to review the recent advancements in understanding the cold tolerance mechanisms of key model organisms, identify key issues in current research, and explore the potential of utilizing big data and omics technology in future studies.

Thyroid abscess associated with thyrotoxicosis caused by Yersinia enterocolitica subsp. palearctica in a patient with follicular adenoma of the thyroid gland.

BACKGROUND: Yersinia enterocolitica is a gram-negative zoonotic bacterial pathogen that is typically transmitted via the fecal-oral route. The most common clinical manifestation of a Y. enterocolitica infection is self-limited gastroenteritis. Although various extraintestinal manifestations of Y. enterocolitica infection have been reported, there are no reports of thyroid abscesses. CASE PRESENTATION: An 89-year-old Japanese man with follicular adenoma of the left thyroid gland was admitted to our hospital with a 2-day history of fever and left neck pain. Laboratory tests revealed low levels of thyroid stimulating hormone and elevated levels of free thyroxine 4. Contrast-enhanced computed tomography showed low-attenuation areas with peripheral enhancement in the left thyroid gland. He was diagnosed with thyroid abscess and thyrotoxicosis, and treatment with intravenous piperacillin-tazobactam was initiated after collecting blood, drainage fluid, and stool samples. The isolated Gram-negative rod bacteria from blood and drainage fluid cultures was confirmed to be Y. enterocolitica. He was diagnosed with thyroid abscess and thyrotoxicosis due to be Y. enterocolitica subsp. palearctica. The piperacillin-tazobactam was replaced with levofloxacin. CONCLUSION: We report a novel case of a thyroid abscess associated with thyrotoxicosis caused by Y. enterocolitica subsp. palearctica in a patient with a follicular thyroid adenoma.

Proteome profiling, biochemical and histological analysis of diclofenac-induced liver toxicity in Yersinia enterocolitica and Lactobacillus fermentum fed rat model: a comparative analysis.

Diclofenac is a hepatotoxic non-steroidal anti-inflammatory drug (NSAID) that affects liver histology and its protein expression levels. Here, we studied the effect of diclofenac on rat liver when co-administrated with either Yersinia enterocolitica strain 8081 serotype O:8 biovar 1B (D*Y) or Lactobacillus fermentum strain 9338 (D*L). Spectroscopic analysis of stool samples showed biotransformation of diclofenac. When compared with each other, D*Y rats lack peaks at 1709 and 1198 cm-1, while D*L rats lack peaks at 1411 cm-1. However, when compared to control, both groups lack peaks at 1379 and 1170 cm-1. Assessment of serum biomarkers of hepatotoxicity indicated significantly altered activities of AST (D*Y: 185.65 ± 8.575 vs Control: 61.9 ± 2.607, D*L: 247.5 ± 5.717 vs Control: 61.9 ± 2.607), ALT (D*Y: 229.8 ± 6.920 vs Control: 70.7 ± 3.109, D*L: 123.75 ± 6.068 vs Control: 70.7 ± 3.109), and ALP (D*Y: 276.4 ± 18.154 vs Control: 320.6 ± 9.829, D*L: 298.5 ± 12.336 vs Control: 320.6 ± 9.829) in IU/L. The analysis of histological alterations showed hepatic sinusoidal dilation with vein congestion and cell infiltration exclusively in D*Y rats along with other histological changes that are common to both test groups, thereby suggesting more pronounced alterations in D*Y rats. Further, LC-MS/MS based label-free quantitation of proteins from liver tissues revealed 74.75% up-regulated, 25.25% down-regulated in D*Y rats and 51.16% up-regulated, 48.84% down-regulated in D*L experiments. The proteomics-identified proteins majorly belonged to metabolism, apoptosis, stress response and redox homeostasis, and detoxification and antioxidant defence that demonstrated the potential damage of rat liver, more pronounced in D*Y rats. Altogether the results are in favor that the administration of lactobacilli somewhat protected the rat hepatic cells against the diclofenac-induced toxicity.

Design and Optimization of a yst-PCR to Detect Yersinia enterocolitica in Meat Food.

In this study, a polymerase chain reaction (PCR) directed to the yst chromosomal gene (yst-PCR) was used as a rapid, sensitive, and specific method to detect Yersinia enterocolitica strains belonging to different biotypes in foods; a competitive Internal Amplification Control (cIAC) is also developed. The cIAC had a molecular weight of 417 bp and was detected until a concentration of 0.85 ng/µL. No other strains of other Yersinia species, nor Enterobacteriales order were detected by this PCR. In pure culture, the detection limit (DL) of the yst-PCR was lower for ystA+ strain (10 colony-forming unit [CFU]/mL) than for ystB+ strain (1 × 102 CFU/mL); which was the concentration detected in Y. enterocolitica inoculated minced meat. The proposed protocol included an enrichment step in peptone sorbitol bile (PSB) broth at 25°C for 24 h followed by isolation on Mac Conkey agar and chromogenic medium. An aliquot of the PSB broth homogenate and a loopful from the confluent zone of solid media were collected to perform DNA extraction for yst-PCR, and typical colonies were characterized by biochemical assays. Among 30 non-contaminated food samples, 4 samples were yst-positive and no Y. enterocolitica isolates were obtained. It is suggested that this yst-PCR could be used in the investigation of Y. enterocolitica in foods.

Controlled Experimental Infection in Pigs with a Strain of Yersinia enterocolitica Harboring Genetic Markers for Human Pathogenicity: Colonization and Stability.

Yersinia enterocolitica (Ye) is one of the major causes of foodborne zoonosis. The BT4/O:3 bioserotype is most commonly isolated in human infections. Pigs are considered the main reservoir of Ye, and hence, understanding the dynamics of infection by this pathogen at the individual and group levels is crucial. In the present study, an experimental model was validated in Large White pigs infected with a BT4/O:3 strain. This study showed that Ye contamination in pigs may occur via the introduction of the bacteria not only by mouth but also by snout, with a colonization process consisting of three periods corresponding to three contamination statuses of pigs: P1, corresponding to the 24 h following ingestion or inhalation of Ye with the appearance of bacteria in tonsils or in feces; P2, from 2 days postinoculation (dpi), corresponding to expansion of Ye and colonization of the digestive system and extraintestinal organs associated with an IgG serological response; and P3, after 21 dpi, corresponding to regression of colonization with intermittent Ye detection in tonsils and feces. Although the inoculated strain persisted up to 56 dpi in all pigs, genetic variations with the loss of the gene yadA (a gene involved in human infection) and the emergence of two new multilocus variable-number tandem-repeat analysis (MLVA) profiles were observed in 33% of the 30 isolates studied. This experimental infection model of pigs by Ye provides new insights into the colonization steps in pigs in terms of bacterial distribution over time and bacterial genetic stability.

Regulation and Functionality of a Holin/Endolysin Pair Involved in Killing of Galleria mellonella and Caenorhabditis elegans by Yersinia enterocolitica.

The insecticidal toxin complex (Tc) proteins are produced by several insect-associated bacteria, including Yersinia enterocolitica strain W22703, which oscillates between two distinct pathogenicity phases in invertebrates and humans. The mechanism by which this high-molecular-weight toxin is released into the extracellular surrounding, however, has not been deciphered. In this study, we investigated the regulation and functionality of a phage-related holin/endolysin (HE) cassette located within the insecticidal pathogenicity island Tc-PAIYe of W22703. Using the Galleria mellonella infection model and luciferase reporter fusions, we revealed that quorum sensing contributes to the insecticidal activity of W22703 upon influencing the transcription of tcaR2, which encodes an activator of the tc and HE genes. In contrast, a lack of the Yersinia modulator, YmoA, stimulated HE gene transcription, and mutant W22703 ΔymoA exhibited a stronger toxicity toward insect larvae than did W22703. A luciferase reporter fusion demonstrated transcriptional activation of the HE cassette in vivo, and a significantly larger extracellular amount of subunit TcaA was found in W22703 ΔymoA relative to its ΔHE mutant. Using competitive growth assays, we demonstrated that at least in vitro, the TcaA release upon HE activity is not mediated by cell lysis of a significant part of the population. Oral infection of Caenorhabditis elegans with a HE deletion mutant attenuated the nematocidal activity of the wild type, similar to the case with a mutant lacking a Tc subunit. We conclude that the dual holin/endolysin cassette of yersiniae is a novel example of a phage-related function adapted for the release of a bacterial toxin. IMPORTANCE Members of the genus Yersinia cause gastroenteritis in humans but also exhibit toxicity toward invertebrates. A virulence factor required for this environmental life cycle stage is the multisubunit toxin complex (Tc), which is distinct from the insecticidal toxin of Bacillus thuringiensis and has the potential to be used in pest control. The mechanism by which this high-molecular-weight Tc is secreted from bacterial cells has not been uncovered. Here, we show that a highly conserved phage-related holin/endolysin pair, which is encoded by the genes holY and elyY located between the Tc subunit genes, is essential for the insecticidal activity of Y. enterocolitica and that its activation increases the amount of Tc subunits in the supernatant. Thus, the dual holY-elyY cassette of Y. enterocolitica constitutes a new example for a type 10 secretion system to release bacterial toxins.

Characterization of phenyl propiolic acid from Proteus mirabilis DMTMMR-11 and Evaluation of its mode of action against Yersinia enterocolitica (MTCC-840) an in-Vitro and in-Vivo based approach.

Foodborne illnesses are pervasive in raising public health concerns in both developed and developing nations. Yersinia enterocolitica a zoonotic bacterial species that causes food-transmitted infections, and gastroenteritis, is its most prevalent clinical manifestation. This study aims to investigate the differences, dependencies, and inhibitory mechanisms between the host and the microbiome. Proteus mirabilis DMTMMR-11, the bacterium found in the human gastrointestinal tract was used for the extraction of intracellular metabolite, because of its beneficial effects on the normal flora of the human gut. Phenyl propiolic acid was identified as the dominant compound in the metabolite after characterization using FT-IR, NMR, and LC-MS-MS. To assess its inhibitory mechanism against Yersinia enterocolitica, the pathogen was subjected to biological characterization by MBC and MIC, resulting in the rate of inhibition at 50 µg/ml. Anti-bacterial curve supports the inhibited growth of Y. enterocolitica. Mechanism of inhibition at its cellular level was indicated by the increase in alkaline phosphate content, which drastically reduced the cell membrane and cell wall potential expanding its permeability by intruding the membrane proteins, which was observed in SEM Imaging. Phenyl propiolic acid efficiently disrupts the biofilm formation by reducing the adherence and increasing the eradication property of the pathogen by exhibiting 65% of inhibition at the minimal duration of 12h. In-vivo study was carried out through host-pathogen interaction in C. elegans, an efficient model organism assessed for its life-span, physiological, and behavioral assays.

The implication of viability and pathogenicity by truncated lipopolysaccharide in Yersinia enterocolitica.

The fast envelope stress responses play a key role in the transmission and pathogenesis of Yersinia enterocolitica, one of the most common foodborne pathogens. Our previous study showed that deletion of the waaF gene, essential for the biosynthesis of lipopolysaccharide (LPS) core polysaccharides, led to the formation of a truncated LPS structure and induced cell envelope stress. This envelope stress may disturb the intracellular signal transduction, thereby affecting the physiological functions of Y. enterocolitica. In this study, truncated LPS caused by waaF deletion was used as a model of envelope stress in Y. enterocolitica. We investigated the mechanisms of envelope stress responses and the cellular functions affected by truncated LPS. Transcriptome analysis and phenotypic validation showed that LPS truncation reduced flagellar assembly, bacterial chemotaxis, and inositol phosphate metabolism, presenting lower pathogenicity and viability both in vivo and in vitro environments. Further 4D label-free phosphorylation analysis confirmed that truncated LPS perturbed multiple intracellular signal transduction pathways. Specifically, a comprehensive discussion was conducted on the mechanisms by which chemotactic signal transduction and Rcs system contribute to the inhibition of chemotaxis. Finally, the pathogenicity of Y. enterocolitica with truncated LPS was evaluated in vitro using IPEC-J2 cells as models, and it was found that truncated LPS exhibited reduced adhesion, invasion, and toxicity of Y. enterocolitica to IPEC-J2 cells. Our research provides an understanding of LPS in the regulation of Y. enterocolitica viability and pathogenicity and, thus, opening new avenues to develop novel food safety strategies or drugs to prevent and control Y. enterocolitica infections. KEY POINTS: • Truncated LPS reduces flagellar assembly, chemotaxis, and inositol phosphate metabolism in Y. enterocolitica. • Truncated LPS reduces adhesion, invasion, and toxicity of Y. enterocolitica to IPEC-J2 cells. • Truncated LPS regulates intracellular signal transduction of Y. enterocolitica.

Isolation, characterization and antimicrobial resistance of Yersinia enterocolitica from Polish cattle and their carcasses.

BACKGROUND: Yersinia enterocolitica is a heterogeneous bacterial species that has been divided into six biotypes and more than 70 serotypes. Each year, the European Food Safety Authority classifies yersiniosis caused by Y. enterocolitica as one of the most important zoonotic diseases. The prevalence of Y. enterocolitica in cattle has not been thoroughly analyzed in Poland, and beef and bovine carcasses contaminated with antimicrobial resistant Y. enterocolitica pose a health risk for both, farm workers and consumers. Therefore, the aim of this study was to evaluate the prevalence of Y. enterocolitica in cattle and to determine the antimicrobial susceptibility of the isolated strains. RESULTS: A total of 1020 samples were analyzed, including 660 rectal swabs collected from live cattle and 360 swabs from cold-stored beef carcasses. The results of this study indicate that Y. enterocolitica was isolated from three of the 15 examined cattle herds and the prevalence within these herds ranged from 0% to nearly 32%. Y. enterocolitica was isolated from 14.7% of the examined heifers, 7.4% of calves and 5.5% of adult cows. More than 65% of the strains were isolated from cold enrichment. The strains isolated from live cattle tested positive for the ystB gene, while ail and ystA genes were not found. Most of the isolated strains belonged to bioserotype 1A/NT. The majority of the isolated strains were resistant to ampicillin, cefalexin and amoxicillin with clavulanic acid, however these are expected phenotypes for Y. enterocolitica. CONCLUSIONS: The results of this study indicate that Y. enterocolitica is present in cattle herds in Poland. The strains isolated from live cattle were ystB-positive, most of them belonged to bioserotype 1A/NT. The prevalence of Y. enterocolitica strains was generally low in cold-stored beef carcasses.

Forgotten but not gone: Yersinia infections in England, 1975 to 2020.

BackgroundYersiniosis is one of the most common food-borne zoonoses in Europe, but there are large variations in the reported incidence between different countries.AimWe aimed to describe the trends and epidemiology of laboratory-confirmed Yersinia infections in England and estimate the average annual number of undiagnosed Yersinia enterocolitica cases, accounting for under-ascertainment.MethodsWe analysed national surveillance data on Yersinia cases reported by laboratories in England between 1975 and 2020 and enhanced surveillance questionnaires from patients diagnosed in a laboratory that has implemented routine Yersinia testing of diarrhoeic samples since 2016.ResultsThe highest incidence of Yersinia infections in England (1.4 cases per 100,000 population) was recorded in 1988 and 1989, with Y. enterocolitica being the predominant species. The reported incidence of Yersinia infections declined during the 1990s and remained low until 2016. Following introduction of commercial PCR at a single laboratory in the South East, the annual incidence increased markedly (13.6 cases per 100,000 population in the catchment area between 2017 and 2020). There were notable changes in age and seasonal distribution of cases over time. The majority of infections were not linked to foreign travel and one in five patients was admitted to hospital. We estimate that around 7,500 Y. enterocolitica infections may be undiagnosed in England annually.ConclusionsFindings suggest a considerable number of undiagnosed yersiniosis cases in England, with possibly important changes in the epidemiology. The apparently low incidence of yersiniosis in England is probably due to limited laboratory testing.

An ultrasensitive aptamer-based fluorescent on/off system for trace amount evaluation of Yersinia enterocolitica in food samples.

An innovative aptamer labeled with 5-FAM has been developed with a high affinity for Yersinia enterocolitica (Y. enterocolitica) using graphene oxide (GO) as a quenching platform. The selectivity of the prepared system was evaluated in the presence of common coexisted bacteria like Yersinia pseudotuberculosis, Staphylococcus aureus, Listeria monocytogenes, Escherichia coli, and Salmonella typhimurium. Some experimental factors like pH and stability were investigated. The results showed that in the absence of Y. enterocolitica, aptamer labeled with 5-FAM was bonded with GO, causing fluorescence to be relatively weak. After the addition of Y. enterocolitica, the aptamer is released from the GO surface and binds to the target bacteria, and significantly increases the fluorescence intensity with an excitation wavelength of 410 nm and an emission wavelength of 530 nm. After optimizing all conditions, the system exhibited a wide linear response for Y. enterocolitica in the concentration range 10 to 1.0 × 109 CFU•mL-1 and the limit of detection (LOD) was 3 CFU•mL-1. This system demonstrated that GO-designed aptamers can be successful in detecting Y. enterocolitica in whole-cell forms, making them potentially useful for screening and rapid detection.

Transcriptomic Analysis Reveals Key Roles of (p)ppGpp and DksA in Regulating Metabolism and Chemotaxis in Yersinia enterocolitica.

The stringent response is a rapid response system that is ubiquitous in bacteria, allowing them to sense changes in the external environment and undergo extensive physiological transformations. However, the regulators (p)ppGpp and DksA have extensive and complex regulatory patterns. Our previous studies demonstrated that (p)ppGpp and DksA in Yersinia enterocolitica positively co-regulated motility, antibiotic resistance, and environmental tolerance but had opposite roles in biofilm formation. To reveal the cellular functions regulated by (p)ppGpp and DksA comprehensively, the gene expression profiles of wild-type, ΔrelA, ΔrelAΔspoT, and ΔdksAΔrelAΔspoT strains were compared using RNA-Seq. Results showed that (p)ppGpp and DksA repressed the expression of ribosomal synthesis genes and enhanced the expression of genes involved in intracellular energy and material metabolism, amino acid transport and synthesis, flagella formation, and the phosphate transfer system. Additionally, (p)ppGpp and DksA inhibited amino acid utilization (such as arginine and cystine) and chemotaxis in Y. enterocolitica. Overall, the results of this study unraveled the link between (p)ppGpp and DksA in the metabolic networks, amino acid utilization, and chemotaxis in Y. enterocolitica and enhanced the understanding of stringent responses in Enterobacteriaceae.

Stringent Response Factor DksA Contributes to Fatty Acid Degradation Function to Influence Cell Membrane Stability and Polymyxin B Resistance of Yersinia enterocolitica.

DksA is a proteobacterial regulator that binds directly to the secondary channel of RNA polymerase with (p)ppGpp and is responsible for various bacterial physiological activities. While (p)ppGpp is known to be involved in the regulation and response of fatty acid metabolism pathways in many foodborne pathogens, the role of DksA in this process has yet to be clarified. This study aimed to characterize the function of DksA on fatty acid metabolism and cell membrane structure in Yersinia enterocolitica. Therefore, comparison analysis of gene expression, growth conditions, and membrane permeabilization among the wide-type (WT), DksA-deficient mutant (YEND), and the complemented strain was carried out. It confirmed that deletion of DksA led to a more than four-fold decrease in the expression of fatty acid degradation genes, including fadADEIJ. Additionally, YEND exhibited a smaller growth gap compared to the WT strain at low temperatures, indicating that DksA is not required for the growth of Y. enterocolitica in cold environments. Given that polymyxin B is a cationic antimicrobial peptide that targets the cell membrane, the roles of DksA under polymyxin B exposure were also characterized. It was found that DksA positively regulates the integrity of the inner and outer membranes of Y. enterocolitica under polymyxin B, preventing the leakage of intracellular nucleic acids and proteins and ultimately reducing the sensitivity of Y. enterocolitica to polymyxin B. Taken together, this study provides insights into the functions of DksA and paves the way for novel fungicide development.

Interplay between the RNA Chaperone Hfq, Small RNAs and Transcriptional Regulator OmpR Modulates Iron Homeostasis in the Enteropathogen Yersinia enterocolitica.

Iron is both essential for and potentially toxic to bacteria, so the precise maintenance of iron homeostasis is necessary for their survival. Our previous study indicated that in the human enteropathogen Yersinia enterocolitica, the regulator OmpR directly controls the transcription of the fur, fecA and fepA genes, encoding the ferric uptake repressor and two transporters of ferric siderophores, respectively. This study was undertaken to determine the significance of the RNA chaperone Hfq and the small RNAs OmrA and RyhB1 in the post-transcriptional control of the expression of these OmpR targets. We show that Hfq silences fur, fecA and fepA expression post-transcriptionally and negatively affects the production of FLAG-tagged Fur, FecA and FepA proteins. In addition, we found that the fur gene is under the negative control of the sRNA RyhB1, while fecA and fepA are negatively regulated by the sRNA OmrA. Finally, our data revealed that the role of OmrA results from a complex interplay of transcriptional and post-transcriptional effects in the feedback circuit between the regulator OmpR and the sRNA OmrA. Thus, the expression of fur, fecA and fepA is subject to complex transcriptional and post-transcriptional regulation in order to maintain iron homeostasis in Y. enterocolitica.

Simple and practical sialoglycan encoding system reveals vast diversity in nature and identifies a universal sialoglycan-recognizing probe derived from AB5 toxin B subunits.

Vertebrate sialic acids (Sias) display much diversity in modifications, linkages, and underlying glycans. Slide microarrays allow high-throughput explorations of sialoglycan-protein interactions. A microarray presenting ~150 structurally defined sialyltrisaccharides with various Sias linkages and modifications still poses challenges in planning, data sorting, visualization, and analysis. To address these issues, we devised a simple 9-digit code for sialyltrisaccharides with terminal Sias and underlying two monosaccharides assigned from the nonreducing end, with 3 digits assigning a monosaccharide, its modifications, and linkage. Calculations based on the encoding system reveal >113,000 likely linear sialyltrisaccharides in nature. Notably, a biantennary N-glycan with 2 terminal sialyltrisaccharides could thus have >1010 potential combinations and a triantennary N-glycan with 3 terminal sequences, >1015 potential combinations. While all possibilities likely do not exist in nature, sialoglycans encode enormous diversity. While glycomic approaches are used to probe such diverse sialomes, naturally occurring bacterial AB5 toxin B subunits are simpler tools to track the dynamic sialome in biological systems. Sialoglycan microarray was utilized to compare sialoglycan-recognizing bacterial toxin B subunits. Unlike the poor correlation between B subunits and species phylogeny, there is stronger correlation with Sia-epitope preferences. Further supporting this pattern, we report a B subunit (YenB) from Yersinia enterocolitica (broad host range) recognizing almost all sialoglycans in the microarray, including 4-O-acetylated-Sias not recognized by a Yersinia pestis orthologue (YpeB). Differential Sia-binding patterns were also observed with phylogenetically related B subunits from Escherichia coli (SubB), Salmonella Typhi (PltB), Salmonella Typhimurium (ArtB), extra-intestinal E.coli (EcPltB), Vibrio cholera (CtxB), and cholera family homologue of E. coli (EcxB).

Inhibitory effect of protocatechualdehyde on Yersinia enterocolitica and its critical virulence factors.

Yersinia enterocolitica (Y. enterocolitica) is a gastrointestinal pathogen that is distributed worldwide, involved in systemic, extraintestinal and invasive infections in immunocompromised patients. Establishment of antibiotic resistance in the pathogen has produced a need for new antibacterial agents. The purpose of this study was to elucidate antibacterial mechanism of protocatechualdehyde (PCA) extracted from the roots of Salvia miltiorrhiza towards Y. enterocolitica, and to investigate effects of PCA on key virulence factors associated with human infection. Present results indicated that PCA exerted its antibacterial activity against Y. enterocolitica mainly by the rapid rise of intracellular reactive oxygen species, leading to change in permeability and integrity of cell membrane, and ultimately decline of membrane potential and intracellular ATP. Furthermore, scanning electron microscopic analysis revealed that Y. enterocolitica presented gradually shrinkage in length and partial wrinkles upon PCA treatment. PCA also effectively decreased motility, biofilm formation, quorum sensing in a dose-dependent manner without affecting bacterial growth. Further, at SICs, PCA substantially suppressed the adhesion and invasion of Y. enterocolitica to HT-29 cells and the downregulation of essential virulence factor-encoding genes unveiled impaired virulence. Overall, the findings revealed the potential of PCA as an alternative antibacterial agent to combat Y. enterocolitica contamination and infections.

Proteomic, biochemical, histopathological, and elevated plus maze analysis reveals the gut damaging role of ketoprofen with Yersinia enterocolitica and altered behavior in Wistar rats.

The long-term use of non-steroidal anti-inflammatory drugs (NSAIDs) is known to damage the intestinal epithelial cells (IECs) that play numerous important roles, including nutrient absorption and barrier protection. In the current study, we determined the effect of ketoprofen on the rat gut when administered with Yersinia enterocolitica. On performing the label-free quantitation of the rat gut proteins, the expression of 494 proteins out of 1628 proteins was altered, which has a profound effect on NF-kB signaling pathway, immune system, dysbiosis, and gut injury. Further, the biochemical [enhanced malondialdehyde (MDA) & hepatic enzyme activities and reduced serotonin & antioxidants levels i.e., catalase (CAT) and superoxide dismutase (SOD)] and histopathological analysis suggested the significant damage in treated rats, compared to control rats. Lastly, the elevated plus maze (EPM) study confirmed high levels of anxiety in treated rats in comparison to the control group. Altogether, results suggest that the co-administration of ketoprofen with Y. enterocolitica damages gut, alters hepatic enzyme activities, and affects behavioral responses in the treated rats.

Mesenteric Lymphadenitis and Terminal Ileitis is Associated With Yersinia Infection: A Meta-analysis.

BACKGROUND: Yersinia infection affects terminal ileum and lymph nodes and could therefore mimic the symptoms of appendicitis. We aimed to systematically characterise the suspected or confirmed abdominal diseases and/or surgeries associated with Yersinia infection. MATERIALS AND METHODS: This systematic review and meta-analysis was reported following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. A protocol (CRD42016053252) was uploaded to PROSPERO. The searches were conducted in PubMed and EMBASE on October 2, 2020. Original reports on patients with abdominal surgical diseases were included. The primary outcome was to characterise suspected or confirmed abdominal surgical diseases and/or surgeries associated with Yersinia infection, while the secondary outcomes were the positive rate of Yersinia species for each disease and surgery, and to investigate the rate of Yersinia spp. in different geographic regions. We calculated the weighted mean prevalence of positive tests for Yersinia spp. for the different diseases and surgeries according to the detection method and for subgroups based on geographic region. RESULTS: From the search, 33 studies were included in the systematic review and 18 in the meta-analysis. Across geographic regions, the weighted mean prevalence for Yersinia spp. was 51% (95% CI 34%-69%) in mesenteric lymphadenitis, 65% (95% CI 45%-85%) in terminal ileitis, and 8% (95% CI 2%-15%) in normal appendices. CONCLUSIONS: Around half of the patients with mesenteric lymphadenitis and terminal ileitis were serologically positive for infections with Yersinia spp. Yersinia infection may cause unnecessary surgery for suspected appendicitis due to symptoms from mesenteric lymphadenitis or terminal ileitis.