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Biomolecules Sep 2021Lipopolysaccharide (LPS), localized in the outer leaflet of the outer membrane, serves as the major surface component of the Gram-negative bacterial cell envelope... (Review)
Review
Lipopolysaccharide (LPS), localized in the outer leaflet of the outer membrane, serves as the major surface component of the Gram-negative bacterial cell envelope responsible for the activation of the host's innate immune system. Variations of the LPS structure utilized by Gram-negative bacteria promote survival by providing resistance to components of the innate immune system and preventing recognition by TLR4. This review summarizes studies of the biosynthesis of Yersinia pseudotuberculosis complex LPSs, and the roles of their structural components in molecular mechanisms of yersiniae pathogenesis and immunogenesis.
Topics: Host-Pathogen Interactions; Humans; Immunity, Innate; Lipid A; Lipopolysaccharides; Molecular Structure; Structure-Activity Relationship; Yersinia pseudotuberculosis
PubMed: 34680043
DOI: 10.3390/biom11101410 -
Microbiology Spectrum Jun 2022The life cycle of Yersinia pestis has changed a lot to adapt to flea-borne transmission since it evolved from an enteric pathogen, Yersinia pseudotuberculosis. Small... (Review)
Review
The life cycle of Yersinia pestis has changed a lot to adapt to flea-borne transmission since it evolved from an enteric pathogen, Yersinia pseudotuberculosis. Small insertions and deletions (indels), especially frameshift mutations, can have major effects on phenotypes and contribute to virulence and host adaptation through gene disruption and inactivation. Here, we analyzed 365 Y. pestis genomes and identified 2,092 genome-wide indels on the core genome. As recently reported in Mycobacterium tuberculosis, we also detected "indel pockets" in Y. pestis, with average complexity scores declining around indel positions, which we speculate might also exist in other prokaryotes. Phylogenic analysis showed that indel-based phylogenic tree could basically reflect the phylogenetic relationships of major phylogroups in Y. pestis, except some inconsistency around the Big Bang polytomy. We observed 83 indels arising in the trunk of the phylogeny, which played a role in accumulation of pseudogenes related to key metabolism and putatively pathogenicity. We also discovered 32 homoplasies at the level of phylogroups and 7 frameshift scars (i.e., disrupted reading frame being rescued by a second frameshift). Additionally, our analysis showed evidence of parallel evolution at the level of genes, with , , , and YPO0624, having enriched mutations in Brazilian isolates, which might be advantageous for Y. pestis to cope with fluctuating environments. The diversified selection signals observed here demonstrates that indels are important contributors to the adaptive evolution of Y. pestis. Meanwhile, we provide potential targets for further exploration, as some genes/pseudogenes with indels we focus on remain uncharacterized. Yersinia pestis, the causative agent of plague, is a highly pathogenic clone of Yersinia pseudotuberculosis. Previous genome-wide SNP analysis provided few adaptive signatures during its evolution. Here by investigating 365 public genomes of Y. pestis, we give a comprehensive overview of general features of genome-wide indels on the core genome and their roles in Y. pestis evolution. Detection of "indel pockets," with average complexity scores declining around indel positions, in both Mycobacterium tuberculosis and Y. pestis, gives us a clue that this phenomenon might appear in other bacterial genomes. Importantly, the identification of four different forms of selection signals in indels would improve our understanding on adaptive evolution of Y. pestis, and provide targets for further physiological mechanism researches of this pathogen. As evolutionary research based on genome-wide indels is still rare in bacteria, our study would be a helpful reference in deciphering the role of indels in other species.
Topics: Evolution, Molecular; Genome, Bacterial; Genomics; INDEL Mutation; Phylogeny; Yersinia pestis; Yersinia pseudotuberculosis
PubMed: 35438532
DOI: 10.1128/spectrum.02242-21 -
Frontiers in Cellular and Infection... 2018The genus includes three human pathogenic species, , the causative agent of the bubonic and pneumonic plague, and enteric pathogens and that cause a number of... (Review)
Review
The genus includes three human pathogenic species, , the causative agent of the bubonic and pneumonic plague, and enteric pathogens and that cause a number of gut-associated diseases. Over the past years a large repertoire of RNA-based regulatory systems has been discovered in these pathogens using different RNA-seq based approaches. Among them are several conserved or species-specific RNA-binding proteins, regulatory and sensory RNAs as well as various RNA-degrading enzymes. Many of them were shown to control the expression of important virulence-relevant factors and have a very strong impact on virulence. The precise targets, the molecular mechanism and their role for pathogenicity is only known for a small subset of identified genus- or species-specific RNA-based control elements. However, the ongoing development of new RNA-seq based methods and data analysis methods to investigate the synthesis, composition, translation, decay, and modification of RNAs in the bacterial cell will help us to generate a more comprehensive view of RNA biology in the near future.
Topics: Animals; Gene Expression Profiling; Gene Expression Regulation, Bacterial; Gene Regulatory Networks; Humans; RNA, Bacterial; Sequence Analysis, RNA; Virulence Factors; Yersinia enterocolitica; Yersinia pestis; Yersinia pseudotuberculosis
PubMed: 30460205
DOI: 10.3389/fcimb.2018.00378 -
Applied and Environmental Microbiology Sep 2018In this study, the prevalence of in wild boars in northeast Germany was determined. For that purpose, the tonsils of 503 wild boars were sampled. The presence of was...
In this study, the prevalence of in wild boars in northeast Germany was determined. For that purpose, the tonsils of 503 wild boars were sampled. The presence of was studied by diagnostic PCR. Positive samples were analyzed by cultural detection using a modified cold enrichment protocol. Ten isolates were obtained, which were characterized by biotyping, molecular serotyping, and multilocus sequence typing (MLST). In addition, whole-genome sequences and the antimicrobial susceptibility of the isolates were analyzed. was isolated from male and female animals, most of which were younger than 1 year. A prevalence of 2% (10/503) was determined by cultural detection, while 6.4% (32/503) of the animals were positive by PCR. The isolates belonged to the biotypes 1 and 2 and serotypes O:1a ( = 7), O:1b ( = 2), and O:4a ( = 1). MLST analysis revealed three sequence types, ST9, ST23, and ST42. Except one isolate, all isolates revealed a strong resistance to colistin. The relationship of the isolates was studied by whole-genome sequencing demonstrating that they belonged to four clades, exhibiting five different pulsed-field gel electrophoresis (PFGE) restriction patterns and a diverse composition of virulence genes. Six isolates harbored the virulence plasmid pYV. Besides two isolates, all isolates contained and genes and a complete or incomplete high-pathogenicity island (HPI). None of them possessed a gene for the superantigen YPM. The study shows that various strains exist in wild boars in northeast Germany, which may pose a risk to humans. is a foodborne pathogen whose occurrence is poorly understood. One reason for this situation is the difficulty in isolating the species. The methods developed for the isolation of are not well suited for We therefore designed a protocol which enabled the isolation of from a relatively high proportion of PCR-positive wild boar tonsils. The study indicates that wild boars in northeast Germany may carry a variety of strains, which differ in terms of their pathogenic potential and other properties. Since wild boars are widely distributed in German forests and even populate cities such as Berlin, they may transmit yersiniae to other animals and crop plants and may thus cause human infections through the consumption of contaminated food. Therefore, the prevalence of should be determined also in other animals and regions to learn more about the natural reservoir of this species.
Topics: Animals; Bacteriological Techniques; Electrophoresis, Gel, Pulsed-Field; Female; Germany; Male; Prevalence; Sus scrofa; Swine; Swine Diseases; Yersinia pseudotuberculosis; Yersinia pseudotuberculosis Infections
PubMed: 29980552
DOI: 10.1128/AEM.00675-18 -
Nature Communications Dec 2022Bacteria have evolved multiple secretion systems for delivering effector proteins into the cytosol of neighboring cells, but the roles of many of these effectors remain...
Bacteria have evolved multiple secretion systems for delivering effector proteins into the cytosol of neighboring cells, but the roles of many of these effectors remain unknown. Here, we show that Yersinia pseudotuberculosis secretes an effector, CccR, that can act both as a toxin and as a transcriptional factor. The effector is secreted by a type VI secretion system (T6SS) and can enter nearby cells of the same species and other species (such as Escherichia coli) via cell-cell contact and in a contact-independent manner. CccR contains an N-terminal FIC domain and a C-terminal DNA-binding domain. In Y. pseudotuberculosis cells, CccR inhibits its own expression by binding through its DNA-binding domain to the cccR promoter, and affects the expression of other genes through unclear mechanisms. In E. coli cells, the FIC domain of CccR AMPylates the cell division protein FtsZ, inducing cell filamentation and growth arrest. Thus, our results indicate that CccR has a dual role, modulating gene expression in neighboring cells of the same species, and inhibiting the growth of competitors.
Topics: Escherichia coli; Transcription Factors; Type VI Secretion Systems; Yersinia pseudotuberculosis; DNA; Bacterial Proteins
PubMed: 36522324
DOI: 10.1038/s41467-022-35522-9 -
The Canadian Veterinary Journal = La... Jan 2024A 6-year-old female huacaya alpaca was referred to the clinic for evaluation with a 1-month history of rapid weight loss, inappetence, lethargy, and severe leukocytosis...
A 6-year-old female huacaya alpaca was referred to the clinic for evaluation with a 1-month history of rapid weight loss, inappetence, lethargy, and severe leukocytosis refractory to medical management. Physical examination revealed a body condition score of 1 out of 5 and a large, firm structure palpable in the right caudoventral abdomen. Abdominal ultrasonographic examination revealed 3 masses with hyperechoic, swirling centers. The largest mass measured 15 cm in diameter with a 2-centimeter capsule, and extended from right of midline into the left inguinal region. Transrectal ultrasonography identified a small uterus and clear delineation between the abdominal masses. Complete blood (cell) count findings were consistent with marked systemic inflammation. Based on initial examination and laboratory findings, exploratory laparotomy was elected. Multiple mesenteric masses strongly adhered to the jejunum were observed within the abdomen. Due to the inoperable conditions and the poor long-term prognosis, the alpaca was euthanized under general anesthesia. Bacterial culture of fluid aspirated from the largest mass revealed . Key clinical message: Clinical progression and attempted treatment of in camelids have not been previously described and the bacterium should be considered as a differential diagnosis for abscessation and persistent leukocytosis. is also considered a zoonotic agent and proper precautions should be taken when handling cases of abdominal abscessation.
Topics: Female; Animals; Yersinia pseudotuberculosis; Camelids, New World; Leukocytosis; Laparotomy
PubMed: 38164383
DOI: No ID Found -
FEMS Microbiology Reviews Mar 2017O-antigen polysaccharide is a major immunogenic feature of the lipopolysaccharide of Gram-negative bacteria, and most species produce a large variety of forms that... (Review)
Review
O-antigen polysaccharide is a major immunogenic feature of the lipopolysaccharide of Gram-negative bacteria, and most species produce a large variety of forms that differ substantially from one another. There are 18 known O-antigen forms in the Yersinia pseudotuberculosis complex, which are typical in being composed of multiple copies of a short oligosaccharide called an O unit. The O-antigen gene clusters are located between the hemH and gsk genes, and are atypical as 15 of them are closely related, each having one of five downstream gene modules for alternative main-chain synthesis, and one of seven upstream modules for alternative side-branch sugar synthesis. As a result, many of the genes are in more than one gene cluster. The gene order in each module is such that, in general, the earlier a gene product functions in O-unit synthesis, the closer the gene is to the 5΄ end for side-branch modules or the 3΄ end for main-chain modules. We propose a model whereby natural selection could generate the observed pattern in gene order, a pattern that has also been observed in other species.
Topics: Evolution, Molecular; O Antigens; Polysaccharides, Bacterial; Yersinia pseudotuberculosis
PubMed: 28364730
DOI: 10.1093/femsre/fux002 -
International Journal of Infectious... May 2016The aim of this study was to exploit the extensive database on strains of Yersinia collected over more than 50 years in France in order to gain an overview of... (Review)
Review
OBJECTIVES
The aim of this study was to exploit the extensive database on strains of Yersinia collected over more than 50 years in France in order to gain an overview of yersiniosis and potential sources of contamination in this country.
METHODS
The 19 670 strains of Yersinia of human, animal, environmental, and food origin isolated in France were grouped by species, biotype, and serotype.
RESULTS
Most human strains (59%) were pathogenic, with a marked predominance of Yersinia enterocolitica bioserotype 4/O:3 (66.8%), followed by Y. enterocolitica 2/O:9 (23.8%) and Yersinia pseudotuberculosis (6.1%). Pigs and pork meat were the nearly exclusive sources of Y. enterocolitica 4/O:3. Other pathogenic strains were rarely isolated from food or environmental samples (0.2%). The major source of pathogenic Yersinia was the animal reservoir, with a remarkable association between Y. enterocolitica 4/O:3 and pigs, Y. pseudotuberculosis and wildlife, Y. enterocolitica 2/O:9 and grazing farm animals, Y. enterocolitica 5/O:2,3 and hares, and Y. enterocolitica 3/O:1,2,3 and chinchillas.
CONCLUSIONS
The frequency of human infection caused by certain Yersinia subgroups might be related to the frequency of exposure to specific animal sources. In contrast, non-pathogenic Yersinia were commonly isolated from foodstuffs and the environment, most probably accounting for the abundance of non-pathogenic Yersinia recovered from human stools.
Topics: Animals; Databases, Factual; Environment; Feces; France; Humans; Red Meat; Swine; Yersinia Infections; Yersinia enterocolitica; Yersinia pseudotuberculosis; Yersinia pseudotuberculosis Infections
PubMed: 26987478
DOI: 10.1016/j.ijid.2016.03.008 -
Nature Microbiology Apr 2023Granulomas are organized immune cell aggregates formed in response to chronic infection or antigen persistence. The bacterial pathogen Yersinia pseudotuberculosis (Yp)...
Granulomas are organized immune cell aggregates formed in response to chronic infection or antigen persistence. The bacterial pathogen Yersinia pseudotuberculosis (Yp) blocks innate inflammatory signalling and immune defence, inducing neutrophil-rich pyogranulomas (PGs) within lymphoid tissues. Here we uncover that Yp also triggers PG formation within the murine intestinal mucosa. Mice lacking circulating monocytes fail to form defined PGs, have defects in neutrophil activation and succumb to Yp infection. Yersinia lacking virulence factors that target actin polymerization to block phagocytosis and reactive oxygen burst do not induce PGs, indicating that intestinal PGs form in response to Yp disruption of cytoskeletal dynamics. Notably, mutation of the virulence factor YopH restores PG formation and control of Yp in mice lacking circulating monocytes, demonstrating that monocytes override YopH-dependent blockade of innate immune defence. This work reveals an unappreciated site of Yersinia intestinal invasion and defines host and pathogen drivers of intestinal granuloma formation.
Topics: Animals; Mice; Monocytes; Yersinia Infections; Yersinia pseudotuberculosis Infections; Yersinia pseudotuberculosis; Virulence Factors; Granuloma
PubMed: 36879169
DOI: 10.1038/s41564-023-01338-6 -
EcoSal Plus Dec 2021Yersinia pseudotuberculosis is an family member that is commonly transmitted by the fecal-oral route to cause infections. From the small intestine, Y.... (Review)
Review
Yersinia pseudotuberculosis is an family member that is commonly transmitted by the fecal-oral route to cause infections. From the small intestine, Y. pseudotuberculosis can invade through Peyer's patches and lymph vessels to infect the mesenteric lymph nodes (MLNs). Infection of MLNs by Y. pseudotuberculosis results in the clinical presentation of mesenteric lymphadenitis. MLNs are important for immune responses to intestinal pathogens and microbiota in addition to their clinical relevance to Y. pseudotuberculosis infections. A characteristic of Y. pseudotuberculosis infection in MLNs is the formation of pyogranulomas. Pyogranulomas are composed of neutrophils, inflammatory monocytes, and lymphocytes surrounding extracellular microcolonies of Y. pseudotuberculosis. Key elements of the complex pathogen-host interaction in MLNs have been identified using mouse infection models. Y. pseudotuberculosis requires the virulence plasmid pYV to induce the formation of pyogranulomas in MLNs. The YadA adhesin and the Ysc-Yop type III secretion system (T3SS) are encoded on pYV. YadA mediates bacterial binding to host receptors, which engages the T3SS to preferentially translocate seven Yop effectors into phagocytes. The effectors promote pathogenesis by blocking innate immune defenses such as superoxide production, degranulation, and inflammasome activation, resulting in survival and growth of Y. pseudotuberculosis. On the other hand, certain effectors can trigger immune defenses in phagocytes. For example, YopJ triggers activation of caspase-8 and an apoptotic cell death response in monocytes within pyogranulomas that limits dissemination of Y. pseudotuberculosis from MLNs to the bloodstream. YopE can be processed as an antigen by phagocytes in MLNs, resulting in T and B cell responses to Y. pseudotuberculosis. Immune responses to Y. pseudotuberculosis in MLNs can also be detrimental to the host in the form of chronic lymphadenopathy. This review focuses on interactions between Y. pseudotuberculosis and phagocytes mediated by pYV that concurrently promote pathogenesis and host defense in MLNs. We propose that MLN pyogranulomas are immunological arenas in which opposing pYV-driven forces determine the outcome of infection in favor of the pathogen or host.
Topics: Animals; Lymph Nodes; Mice; Monocytes; Plasmids; Virulence; Yersinia pseudotuberculosis
PubMed: 34910573
DOI: 10.1128/ecosalplus.ESP-0014-2021