Identification of a conjunctivitis-associated gene locus from the virulence plasmid of Yersinia enterocolitica.

PubMed

Miliotis, M D; Morris, J G; Cianciosi, S; Wright, A C; Wood, P K; Robins-Browne, R M

1990-08-01

The virulence plasmid (pYV) of Yersinia enterocolitica is necessary for production of conjunctivitis in guinea pigs and for mouse lethality. To identify the genes responsible for production of conjunctivitis in guinea pigs, we subcloned the BamHI and SalI restriction fragments of the virulence plasmid of Y. enterocolitica A2635 (serotype O:8) into derivatives of the broad-host-range plasmid pRK290 and introduced the constructions into plasmid-negative Y. enterocolitica strains. A mild, transient conjunctivitis was evident 24 h after inoculation with strains containing a 2.8-kilobase (kb) BamHI fragment of pYV. These strains were cytotoxic to HEp-2 cells but did not cause death in iron-loaded adult mice. When the 2.8- and adjacent 0.5-kb BamHI fragments were deleted from the virulence plasmid of a fully virulent Y. enterocolitica isolate, the resultant strain did not cause conjunctivitis in guinea pigs and was not cytotoxic to HEp-2 cells. However, the strain with the deletion appeared to be more virulent for mice, with more rapid dissemination after orogastric inoculation, compared with that of the parent strain. When the deletion was complemented by introduction of a plasmid containing the 2.8-kb BamHI fragment, the strain again caused conjunctivitis but had decreased virulence for mice.

An Outbreak of Yersinia enterocolitica in a Captive Colony of African Green Monkeys (Chlorocebus aethiops sabaeus) in the Caribbean

PubMed Central

Soto, Esteban; Griffin, Matt; Verma, Ashutosh; Castillo-Alcala, Fernanda; Beierschmitt, Amy; Beeler-Marfisi, Janet; Arauz, Maziel; Illanes, Oscar

2013-01-01

Yersinia enterocolitica is a zoonotic gram-negative pathogen that causes mesenteric lymphadenitis, terminal ileitis, acute gastroenteritis, and septicemia in domestic animals and primates. In 2012, 46 captive African green monkeys (Chlorocebus aethiops sabaeus) died during an outbreak of acutely fatal enteric disease over a period of 1 mo on the island of St Kitts. The affected monkeys presented with a history of mucohemorrhagic diarrhea, marked dehydration, and depression. Fifteen bacterial isolates were recovered from the spleen, liver, and lungs of affected monkeys. All isolates were identified as Y. enterocolitica by biochemical analysis and sequence comparison of the 16S rRNA gene. Phenotypic and genotypic analysis of the recovered isolates revealed homogeneity among the recovered bacteria, and all isolates gave a random amplified polymorphic DNA pattern resembling that given by genotype D under serotypes O:7,8. This outbreak represents the first isolation and characterization of Y. enterocolitica as the causative agent of fatal enteric disease in primates in the Caribbean. PMID:24210021

Yersinia enterocolitica-Induced Interleukin-8 Secretion by Human Intestinal Epithelial Cells Depends on Cell Differentiation

PubMed Central

Schulte, Ralf; Autenrieth, Ingo B.

1998-01-01

In response to bacterial entry epithelial cells up-regulate expression and secretion of various proinflammatory cytokines, including interleukin-8 (IL-8). We studied Yersinia enterocolitica O:8-induced IL-8 secretion by intestinal epithelial cells as a function of cell differentiation. For this purpose, human T84 intestinal epithelial cells were grown on permeable supports, which led to the formation of tight monolayers of polarized intestinal epithelial cells. To analyze IL-8 secretion as a function of cell differentiation, T84 monolayers were infected from the apical or basolateral side at different stages of differentiation. Both virulent (plasmid-carrying) and nonvirulent (plasmid-cured) Y. enterocolitica strains invaded nondifferentiated T84 cells from the apical side. Yersinia invasion into T84 cells was followed by secretion of IL-8. After polarized differentiation of T84 cells Y. enterocolitica was no longer able to invade from the apical side or to induce IL-8 secretion by T84 cells. However, Y. enterocolitica invaded and induced IL-8 secretion by polarized T84 cells after infection from the basolateral side. Basolateral invasion required the presence of the Yersinia invasion locus, inv, suggesting β1 integrin-mediated cell invasion. After basolateral infection, Yersinia-induced IL-8 secretion was not strictly dependent on cell invasion. Thus, although the plasmid-carrying Y. enterocolitica strain did not significantly invade T84 cells, it induced significant IL-8 secretion. Taken together, these data show that Yersinia-triggered IL-8 secretion by intestinal epithelial cells depends on cell differentiation and might be induced by invasion as well as by basolateral adhesion, suggesting that invasion is not essential for triggering IL-8 production. Whether IL-8 secretion is involved in the pathogenesis of Yersinia-induced abscess formation in Peyer’s patch tissue remains to be shown. PMID:9488416

Detection of Yersinia enterocolitica serotype O:9 in the faeces of cattle with false positive reactions in serological tests for brucellosis in Ireland.

PubMed

O'Grady, Don; Kenny, Kevin; Power, Seamus; Egan, John; Ryan, Fergus

2016-10-01

Intestinal infection by Yersinia enterocolitica serotype O:9 (YeO9) in cattle has been linked to false positive serological reactivity (FPSR) in diagnostic tests for brucellosis. Although eradicated in Ireland, brucellosis monitoring still identifies seropositive animals, usually one or two (termed singletons) per herd, which are classed as FPSR. To investigate a link between FPSR and YeO9, faeces and blood were collected from singleton FPSR cattle, and from companion animals, in eight selected herds with more than one FPSR animal, for YeO9 culture and Brucella serology. YeO9 was isolated from 76/474 (16%) FPSR singletons in 309 herds, but not from any of 621 animals in 122 control non-FPSR herds. In the FPSR herds 52/187 (27.8%) animals were culture positive, and 17% of the isolates were from seronegative animals. Seropositive animals were more likely to have a rising antibody titre when culture positive. Copyright © 2016 Elsevier Ltd. All rights reserved.

Prevalence, characterization, and antimicrobial resistance of Yersinia species and Yersinia enterocolitica isolated from raw milk in farm bulk tanks.

PubMed

Jamali, Hossein; Paydar, Mohammadjavad; Radmehr, Behrad; Ismail, Salmah

2015-02-01

The aims of this study were to investigate the prevalence and to characterize and determine the antibiotic resistance of Yersinia spp. isolates from raw milk. From September 2008 to August 2010, 446 raw milk samples were obtained from farm bulk milk tanks in Varamin, Iran. Yersinia spp. were detected in 29 (6.5%) samples, out of which 23 (79.3%), 5 (17.2%), and 1 (3.4%) were isolated from cow, sheep, and goat raw milk, respectively. The most common species isolated was Yersinia enterocolitica (65.5%), followed by Yersinia frederiksenii (31%), and Yersinia kristensenii (3.4%). Of the 19 Y. enterocolitica isolates, 14 (73.7%) were grouped into bioserotype 1A/O:9, 4 (21.1%) belonged to bioserotype 1B:O8, 1 (5.3%) belonged to bioserotype 4/O:3, and 1 isolate (biotype 1A) was not typable. All the isolates of biotypes 1B and 4harbored both the ystA and ail genes. However, all the isolates of biotype 1A were only positive for the ystB gene. The tested Yersinia spp. showed the highest percentages of resistance to tetracycline (48.3%), followed by ciprofloxacin and cephalothin (each 17.2%), ampicillin (13.8%), streptomycin (6.9%), and amoxicillin and nalidixic acid (each 3.4%). All of the tested isolates demonstrated significant sensitivity to gentamicin and chloramphenicol. Recovery of potentially pathogenic Y. enterocolitica from raw milk indicates high risks of yersiniosis associated with consumption of raw milk. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Isolation and characterization of Yersinia-specific bacteriophages from pig stools in Finland.

PubMed

Salem, M; Virtanen, S; Korkeala, H; Skurnik, M

2015-03-01

Bacteriophages infect bacteria, and they are present everywhere in the world including the intestinal tracts of animals. Yersiniosis is a common foodborne infection caused by Yersinia enterocolitica and Yersinia pseudotuberculosis. As these bacteria are frequently isolated from pigs, we wanted to know whether Yersinia-specific bacteriophages are also present in the pig stools and, if so, whether there is a positive or negative association between the prevalence of the Yersinia phages and the pathogenic Yersinia in the stool samples. Altogether 793 pig stool samples collected between November 2010 and March 2012 from 14 Finnish pig farms were screened for the presence of bacteriophages able to infect Y. enterocolitica serotype O:3, O:5,27 or O:9 strains, or Y. pseudotuberculosis serotype O:1a, O:1b or O:3 strains. Yersinia phages were isolated from 90 samples from eight farms. Yersinia enterocolitica O:3 was infected by 59 phages, 28 phages infected serotypes O:3 and O:5,27, and eight phages infected serotypes O:3, O:5,27 and O:9, and Y. pseudotuberculosis O:1a by eight phages. Many phages originating from pigs in the same farm were identical based on their restriction enzyme digestion patterns; 20 clearly different phages were selected for further characterization. Host ranges of these phages were tested with 94 Yersinia strains. Six of the phages infected eight strains, 13 phages infected three strains, and one phage infected only one strain, indicating that the phages had a relatively narrow host range. There was a clear association between the presence of the host bacteria and specific phages in the stools. The isolated bacteriophages may have potential as biocontrol agents for yersiniosis in both humans and pigs in future, and as alternatives or in addition to antibiotics. To our knowledge, this is the first reported isolation of Yersinia-specific phages from pig stool samples. © 2014 The Society for Applied Microbiology.

Low prevalence of human enteropathogenic Yersinia spp. in brown rats (Rattus norvegicus) in Flanders.

PubMed

Rouffaer, Lieze Oscar; Baert, Kristof; Van den Abeele, Anne-Marie; Cox, Ivo; Vanantwerpen, Gerty; De Zutter, Lieven; Strubbe, Diederik; Vranckx, Katleen; Lens, Luc; Haesebrouck, Freddy; Delmée, Michel; Pasmans, Frank; Martel, An

2017-01-01

Brown rats (Rattus norvegicus) have been identified as potential carriers of Yersinia enterocolitica and Y. pseudotuberculosis, the etiological agents of yersiniosis, the third most reported bacterial zoonosis in Europe. Enteropathogenic Yersinia spp. are most often isolated from rats during yersiniosis cases in animals and humans, and from rats inhabiting farms and slaughterhouses. Information is however lacking regarding the extent to which rats act as carriers of these Yersinia spp.. In 2013, 1088 brown rats across Flanders, Belgium, were tested for the presence of Yersinia species by isolation method. Identification was performed using MALDI-TOF MS, PCR on chromosomal- and plasmid-borne virulence genes, biotyping and serotyping. Yersinia spp. were isolated from 38.4% of the rats. Of these, 53.4% were designated Y. enterocolitica, 0.7% Y. pseudotuberculosis and 49.0% other Yersinia species. Two Y. enterocolitica possessing the virF-, ail- and ystA-gene were isolated. Additionally, the ystB-gene was identified in 94.1% of the other Y. enterocolitica isolates, suggestive for biotype 1A. Three of these latter isolates simultaneously possessed the ail-virulence gene. Significantly more Y. enterocolitica were isolated during winter and spring compared to summer. Based on our findings we can conclude that brown rats are frequent carriers for various Yersinia spp., including Y. pseudotuberculosis and (human pathogenic) Y. enterocolitica which are more often isolated during winter and spring.

Low prevalence of human enteropathogenic Yersinia spp. in brown rats (Rattus norvegicus) in Flanders

PubMed Central

Rouffaer, Lieze Oscar; Baert, Kristof; Van den Abeele, Anne-Marie; Cox, Ivo; Vanantwerpen, Gerty; De Zutter, Lieven; Strubbe, Diederik; Vranckx, Katleen; Lens, Luc; Haesebrouck, Freddy; Delmée, Michel; Pasmans, Frank; Martel, An

2017-01-01

Brown rats (Rattus norvegicus) have been identified as potential carriers of Yersinia enterocolitica and Y. pseudotuberculosis, the etiological agents of yersiniosis, the third most reported bacterial zoonosis in Europe. Enteropathogenic Yersinia spp. are most often isolated from rats during yersiniosis cases in animals and humans, and from rats inhabiting farms and slaughterhouses. Information is however lacking regarding the extent to which rats act as carriers of these Yersinia spp.. In 2013, 1088 brown rats across Flanders, Belgium, were tested for the presence of Yersinia species by isolation method. Identification was performed using MALDI-TOF MS, PCR on chromosomal- and plasmid-borne virulence genes, biotyping and serotyping. Yersinia spp. were isolated from 38.4% of the rats. Of these, 53.4% were designated Y. enterocolitica, 0.7% Y. pseudotuberculosis and 49.0% other Yersinia species. Two Y. enterocolitica possessing the virF-, ail- and ystA-gene were isolated. Additionally, the ystB-gene was identified in 94.1% of the other Y. enterocolitica isolates, suggestive for biotype 1A. Three of these latter isolates simultaneously possessed the ail-virulence gene. Significantly more Y. enterocolitica were isolated during winter and spring compared to summer. Based on our findings we can conclude that brown rats are frequent carriers for various Yersinia spp., including Y. pseudotuberculosis and (human pathogenic) Y. enterocolitica which are more often isolated during winter and spring. PMID:28403184

Fast and Sensitive Detection of Enteropathogenic Yersinia by Immunoassays

PubMed Central

Laporte, Jérôme; Savin, Cyril; Lamourette, Patricia; Devilliers, Karine; Volland, Hervé; Carniel, Elisabeth; Créminon, Christophe

2014-01-01

Yersinia enterocolitica and Yersinia pseudotuberculosis, the two Yersinia species that are enteropathogenic for humans, are distributed worldwide and frequently cause diarrhea in inhabitants of temperate and cold countries. Y. enterocolitica is a major cause of foodborne disease resulting from consumption of contaminated pork meat and is further associated with substantial economic cost. However, investigation of enteropathogenic Yersinia species is infrequently performed routinely in clinical laboratories because of their specific growth characteristics, which make difficult their isolation from stool samples. Moreover, current isolation procedures are time-consuming and expensive, thus leading to underestimates of the incidence of enteric yersiniosis, inappropriate prescriptions of antibiotic treatments, and unnecessary appendectomies. The main objective of the study was to develop fast, sensitive, specific, and easy-to-use immunoassays, useful for both human and veterinary diagnosis. Monoclonal antibodies (MAbs) directed against Y. enterocolitica bioserotypes 2/O:9 and 4/O:3 and Y. pseudotuberculosis serotypes I and III were produced. Pairs of MAbs were selected by testing their specificity and affinity for enteropathogenic Yersinia and other commonly found enterobacteria. Pairs of MAbs were selected to develop highly sensitive enzyme immunoassays (EIAs) and lateral flow immunoassays (LFIs or dipsticks) convenient for the purpose of rapid diagnosis. The limit of detection of the EIAs ranged from 3.2 × 103 CFU/ml to 8.8 × 104 CFU/ml for pathogenic serotypes I and III of Y. pseudotuberculosis and pathogenic bioserotypes 2/O:9 and 4/O:3 of Y. enterocolitica and for the LFIs ranged from 105 CFU/ml to 106 CFU/ml. A similar limit of detection was observed for artificially contaminated human feces. PMID:25355759

In situ structural analysis of the Yersinia enterocolitica injectisome

PubMed Central

Kudryashev, Mikhail; Stenta, Marco; Schmelz, Stefan; Amstutz, Marlise; Wiesand, Ulrich; Castaño-Díez, Daniel; Degiacomi, Matteo T; Münnich, Stefan; Bleck, Christopher KE; Kowal, Julia; Diepold, Andreas; Heinz, Dirk W; Dal Peraro, Matteo; Cornelis, Guy R; Stahlberg, Henning

2013-01-01

Injectisomes are multi-protein transmembrane machines allowing pathogenic bacteria to inject effector proteins into eukaryotic host cells, a process called type III secretion. Here we present the first three-dimensional structure of Yersinia enterocolitica and Shigella flexneri injectisomes in situ and the first structural analysis of the Yersinia injectisome. Unexpectedly, basal bodies of injectisomes inside the bacterial cells showed length variations of 20%. The in situ structures of the Y. enterocolitica and S. flexneri injectisomes had similar dimensions and were significantly longer than the isolated structures of related injectisomes. The crystal structure of the inner membrane injectisome component YscD appeared elongated compared to a homologous protein, and molecular dynamics simulations documented its elongation elasticity. The ring-shaped secretin YscC at the outer membrane was stretched by 30–40% in situ, compared to its isolated liposome-embedded conformation. We suggest that elasticity is critical for some two-membrane spanning protein complexes to cope with variations in the intermembrane distance. DOI: http://dx.doi.org/10.7554/eLife.00792.001 PMID:23908767

Yersinia enterocolitica YopH-Deficient Strain Activates Neutrophil Recruitment to Peyer's Patches and Promotes Clearance of the Virulent Strain.

PubMed

Dave, Mabel N; Silva, Juan E; Eliçabe, Ricardo J; Jeréz, María B; Filippa, Verónica P; Gorlino, Carolina V; Autenrieth, Stella; Autenrieth, Ingo B; Di Genaro, María S

2016-11-01

Yersinia enterocolitica evades the immune response by injecting Yersinia outer proteins (Yops) into the cytosol of host cells. YopH is a tyrosine phosphatase critical for Yersinia virulence. However, the mucosal immune mechanisms subverted by YopH during in vivo orogastric infection with Y. enterocolitica remain elusive. The results of this study revealed neutrophil recruitment to Peyer's patches (PP) after infection with a YopH-deficient mutant strain (Y. enterocolitica ΔyopH). While the Y. enterocolitica wild-type (WT) strain in PP induced the major neutrophil chemoattractant CXCL1 mRNA and protein levels, infection with the Y. enterocolitica ΔyopH mutant strain exhibited a higher expression of the CXCL1 receptor, CXCR2, in blood neutrophils, leading to efficient neutrophil recruitment to the PP. In contrast, migration of neutrophils into PP was impaired upon infection with Y. enterocolitica WT strain. In vitro infection of blood neutrophils revealed the involvement of YopH in CXCR2 expression. Depletion of neutrophils during Y. enterocolitica ΔyopH infection raised the bacterial load in PP. Moreover, the clearance of WT Y. enterocolitica was improved when an equal mixture of Y. enterocolitica WT and Y. enterocolitica ΔyopH strains was used in infecting the mice. This study indicates that Y. enterocolitica prevents early neutrophil recruitment in the intestine and that the effector protein YopH plays an important role in the immune evasion mechanism. The findings highlight the potential use of the Y. enterocolitica YopH-deficient strain as an oral vaccine carrier. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Averting Behavior Framework for Perceived Risk of Yersinia enterocolitica Infections.

PubMed

Aziz, Sonia N; Aziz, Khwaja M S

2012-01-01

The focus of this research is to present a theoretical model of averting actions that households take to avoid exposure to Yersinia enterocolitica in contaminated food. The cost of illness approach only takes into account the value of a cure, while the averting behavior approach can estimate the value of preventing the illness. The household, rather than the individual, is the unit of analysis in this model, where one household member is primarily responsible for procuring uncontaminated food for their family. Since children are particularly susceptible and live with parents who are primary decision makers for sustenance, the designated household head makes the choices that are investigated in this paper. This model uses constrained optimization to characterize activities that may offer protection from exposure to Yersinia enterocolitica contaminated food. A representative household decision maker is assumed to allocate family resources to maximize utility of an altruistic parent, an assumption used in most research involving economics of the family.

Yersinia enterocolitica and related species isolated from wildlife in New York State.

PubMed Central

Shayegani, M; Stone, W B; DeForge, I; Root, T; Parsons, L M; Maupin, P

1986-01-01

Fecal specimens for Yersinia screening were obtained from a variety of wild mammals, birds, reptiles, fish, and invertebrates throughout New York State. One specimen from each of 1,426 animals was examined. A total of 148 isolates of Yersinia enterocolitica and related species were obtained from 133 (9.3%) of the animals. Y. enterocolitica was isolated from 100 (7%) of the animals tested, including 81 (10%) of 812 mammals and 19 (3.3%) of 573 birds. Y. intermedia, Y. frederiksenii, and Y. kristensenii were isolated from 39 (2.7%), 5 (0.35%), and 4 (0.28%) animals, respectively. The 81 Y. enterocolitica isolates from mammals belonged to 15 serogroups and included three pathogens: two isolates of typical serogroup 0:8, the "American strain," one from a gray fox (Urocyon cinereoargenteus) and one from a porcupine (Erethizon dorsatum); and one isolate of serogroup 0:3, bacteriophage type IXb, the "Canadian strain," from a gray fox. The most prevalent serogroups recovered from mammals were 0:6,31 (16 isolates) and 0:5,27 (6 isolates). The 19 isolates of Y. enterocolitica from birds belonged to nine serogroups and included one serogroup 0:6,31 isolate from a common grackle (Quiscalus quiscula) and two serogroup 0:5,27 isolates from great horned owls (Bubo virginianus). PMID:3767355

The detection of Yersinia enterocolitica in surface water by quantitative PCR amplification of the ail and yadA genes.

PubMed

Cheyne, Bo M; Van Dyke, Michele I; Anderson, William B; Huck, Peter M

2010-09-01

Yersinia enterocolitica has been detected in surface water, and drinking untreated water is a risk factor for infection. PCR-based methods have been used to detect Y. enterocolitica in various sample types, but quantitative studies have not been conducted in water. In this study, quantitative PCR (qPCR)-based methods targeting the Yersinia virulence genes ail and yadA were used to survey the Grand River watershed in southern Ontario, Canada. Initial testing of reference strains showed that ail and yadA PCR assays were specific for pathogenic biotypes of Y. enterocolitica; however the genes were also detected in one clinical Yersinia intermedia isolate. A survey of surface water from the Grand River watershed showed that both genes were detected at five sampling locations, with the ail and yadA genes detected in 38 and 21% of samples, respectively. Both genes were detected more frequently at colder water temperatures. A screening of Yersinia strains isolated from the watershed showed that the ail gene was detected in three Y. enterocolitica 1A/O:5 isolates. Results of this study show that Yersinia virulence genes were commonly detected in a watershed used as a source of drinking water, and that the occurrence of these genes was seasonal.

Structure of a pectin methylesterase from Yersinia enterocolitica.

PubMed

Boraston, Alisdair B; Abbott, D Wade

2012-02-01

Pectin methylesterases (PMEs) are family 8 carbohydrate esterases (CE8s) which remove the methyl group from methylesterified galacturonic acid (GalA) residues within pectin. Although the role of pectinases such as PMEs within dedicated phytopathogens has been well established, the significance of homologous enzymes found within the genomes of human enteropathogens remains to be determined. Presented here is the low-resolution (3.5 Å) structure of the CE8 from Yersinia enterocolitica (YeCE8). The high degree of structural conservation in the topology of the active-site cleft and catalytic apparatus that is shared with a characterized PME from a bacterial phytopathogen (i) indicates that YeCE8 is active on methylated pectin and (ii) highlights a more prominent role for pectin utilization in Yersinia than in other enteropathogenic species.

Waterborne Yersinia enterocolitica in the midwest United States.

PubMed

Saari, T N; Jansen, G P

1979-01-01

One hundred forty strains of waterborne Y. enterocolitica were isolated from Wisconsin and Colorado rivers, lakes and wells between October 1974 and March 1976- Direct-plating of unconcentrated water specimens on deoxycholate-citrate-mannitol (Y-M) agar resulted in 89 isolates. Prolonged incubation of specimens in cooked meat broth produced 51 additional strains. Most organisms were indole-positive, Niléln biotype 1 with 24% belonging to the rhamnophilum subgroup. Twenty-three serotypes were represented with 13% reacting as 0:4,32/33, 43% of the isolates could not be serotyped. Twelve organisms were phagetyped as either XO or XZ.

Pathogenic strains of Yersinia enterocolitica isolated from domestic dogs (Canis familiaris) belonging to farmers are of the same subtype as pathogenic Y. enterocolitica strains isolated from humans and may be a source of human infection in Jiangsu Province, China.

PubMed

Wang, Xin; Cui, Zhigang; Wang, Hua; Tang, Liuying; Yang, Jinchuan; Gu, Ling; Jin, Dong; Luo, Longze; Qiu, Haiyan; Xiao, Yuchun; Xiong, Haiping; Kan, Biao; Xu, Jianguo; Jing, Huaiqi

2010-05-01

We isolated 326 Yersinia enterocolitica strains from 5,919 specimens from patients with diarrhea at outpatient clinics, livestock, poultry, wild animals, insect vectors, food, and the environment in the cities of Nantong and Xuzhou in Jiangsu Province, China, from 2004 to 2008. The results showed that the 12 pathogenic strains were of the O:3 serotype. Six strains were isolated from domestic dogs (Canis familiaris) belonging to farmers and were found to be the primary carriers of pathogenic Y. enterocolitica strains, especially in Xuzhou. Pulsed-field gel electrophoresis analysis of the pathogenic strains from dogs belonging to farmers showed that they shared the same patterns as strains from diarrhea patients isolated in 1994. This indicates that the strains from domestic dogs have a close correlation with the strains causing human infections.

Stress responses in pathogenic Yersinia enterocolitica with reference to the stability of the virulence plasmid in food

USDA-ARS?s Scientific Manuscript database

Yersinia enterocolitica has been associated with food-borne illness, most often due the ingestion of pork products. The pathogenic effects induced by a Y. enterocolitica infection are caused by the interplay of chromosomal genes and a virulence plasmid, pYV. Generally, the plasmid is lost during g...

Structure of a pectin methylesterase from Yersinia enterocolitica

PubMed Central

Boraston, Alisdair B.; Abbott, D. Wade

2012-01-01

Pectin methylesterases (PMEs) are family 8 carbohydrate esterases (CE8s) which remove the methyl group from methylesterified galacturonic acid (GalA) residues within pectin. Although the role of pectinases such as PMEs within dedicated phytopathogens has been well established, the significance of homologous enzymes found within the genomes of human enteropathogens remains to be determined. Presented here is the low-resolution (3.5 Å) structure of the CE8 from Yersinia enterocolitica (YeCE8). The high degree of structural conservation in the topology of the active-site cleft and catalytic apparatus that is shared with a characterized PME from a bacterial phytopathogen (i) indicates that YeCE8 is active on methylated pectin and (ii) highlights a more prominent role for pectin utilization in Yersinia than in other enteropathogenic species. PMID:22297983

Evaluation of isolation methods for pathogenic Yersinia enterocolitica from pig intestinal content.

PubMed

Laukkanen, R; Hakkinen, M; Lundén, J; Fredriksson-Ahomaa, M; Johansson, T; Korkeala, H

2010-03-01

The aim of this study was to evaluate the efficiency of four isolation methods for the detection of pathogenic Yersinia enterocolitica from pig intestinal content. The four methods comprised of 15 isolation steps using selective enrichments (irgasan-ticarcillin-potassium chlorate and modified Rappaport broth) and mildly selective enrichments at 4 or 25 degrees C. Salmonella-Shigella-desoxycholate-calcium chloride agar, cefsulodin-irgasan-novobiocin agar were used as plating media. The most sensitive method detected 78% (53/68) of the positive samples. Individual isolation steps using cold enrichment as the only enrichment or as a pre-enrichment step with further selective enrichment showed the highest sensitivities (55-66%). All isolation methods resulted in high numbers of suspected colonies not confirmed as pathogenic Y. enterocolitica. Cold enrichment should be used in the detection of pathogenic Y. enterocolitica from pig intestinal contents. In addition, more than one parallel isolation step is needed. The study shows that depending on the isolation method used for Y. enterocolitica, the detected prevalence of Y. enterocolitica in pig intestinal contents varies greatly. More selective and sensitive isolation methods need to be developed for pathogenic Y. enterocolitica.

Pathogenic Strains of Yersinia enterocolitica Isolated from Domestic Dogs (Canis familiaris) Belonging to Farmers Are of the Same Subtype as Pathogenic Y. enterocolitica Strains Isolated from Humans and May Be a Source of Human Infection in Jiangsu Province, China ▿ ‡

PubMed Central

Wang, Xin; Cui, Zhigang; Wang, Hua; Tang, Liuying; Yang, Jinchuan; Gu, Ling; Jin, Dong; Luo, Longze; Qiu, Haiyan; Xiao, Yuchun; Xiong, Haiping; Kan, Biao; Xu, Jianguo; Jing, Huaiqi

2010-01-01

We isolated 326 Yersinia enterocolitica strains from 5,919 specimens from patients with diarrhea at outpatient clinics, livestock, poultry, wild animals, insect vectors, food, and the environment in the cities of Nantong and Xuzhou in Jiangsu Province, China, from 2004 to 2008. The results showed that the 12 pathogenic strains were of the O:3 serotype. Six strains were isolated from domestic dogs (Canis familiaris) belonging to farmers and were found to be the primary carriers of pathogenic Y. enterocolitica strains, especially in Xuzhou. Pulsed-field gel electrophoresis analysis of the pathogenic strains from dogs belonging to farmers showed that they shared the same patterns as strains from diarrhea patients isolated in 1994. This indicates that the strains from domestic dogs have a close correlation with the strains causing human infections. PMID:20181899

Transcriptional activation of the tad type IVb pilus operon by PypB in Yersinia enterocolitica.

PubMed

Schilling, Jennifer; Wagner, Karin; Seekircher, Stephanie; Greune, Lilo; Humberg, Verena; Schmidt, M Alexander; Heusipp, Gerhard

2010-07-01

Type IV pili are virulence factors in various bacteria and mediate, among other functions, the colonization of diverse surfaces. Various subclasses of type IV pili have been identified, but information on pilus expression, biogenesis, and the associated phenotypes is sparse for the genus Yersinia. We recently described the identification of PypB as a transcriptional regulator in Yersinia enterocolitica. Here we show that the pypB gene is associated with the tad locus, a genomic island that is widespread among bacterial and archaeal species. The genetic linkage of pypB with the tad locus is conserved throughout the yersiniae but is not found among other bacteria carrying the tad locus. We show that the genes of the tad locus form an operon in Y. enterocolitica that is controlled by PypB and that pypB is part of this operon. The tad genes encode functions necessary for the biogenesis of the Flp subfamily of type IVb pili initially described for Aggregatibacter actinomycetemcomitans to mediate a tight-adherence phenotype. In Y. enterocolitica, the Flp pilin protein shows some peculiarities in its amino acid sequence that imply similarities as well as differences compared to typical motifs found in the Flp subtype of type IVb pili. Flp is expressed and processed after PypB overproduction, resulting in microcolony formation but not in increased adherence to biotic or abiotic surfaces. Our data describe the transcriptional regulation of the tad type IVb pilus operon by PypB in Y. enterocolitica but fail to show most previously described phenotypes associated with this type of pilus in other bacteria.

Yersinia enterocolitica Outbreak Associated with Ready-to-Eat Salad Mix, Norway, 2011

PubMed Central

Heier, Berit Tafjord; Nygård, Karin; Stalheim, Torunn; Cudjoe, Kofitsyo S.; Skjerdal, Taran; Wester, Astrid Louise; Lindstedt, Bjørn-Arne; Stavnes, Trine-Lise; Vold, Line

2012-01-01

In 2011, an outbreak of illness caused by Yersinia enterocolitica O:9 in Norway was linked to ready-to-eat salad mix, an unusual vehicle for this pathogen. The outbreak illustrates the need to characterize isolates of this organism, and reinforces the need for international traceback mechanisms for fresh produce. PMID:22932318

A Lactobacillus plantarum strain isolated from kefir protects against intestinal infection with Yersinia enterocolitica O9 and modulates immunity in mice.

PubMed

De Montijo-Prieto, Soumi; Moreno, Encarnación; Bergillos-Meca, Triana; Lasserrot, Agustín; Ruiz-López, María-Dolores; Ruiz-Bravo, Alfonso; Jiménez-Valera, María

2015-10-01

Lactobacillus plantarum C4, previously isolated from kefir and characterized as a potential probiotic strain, was tested for its protective and immunomodulatory capacity in a murine model of yersiniosis. The inoculation of BALB/c mice with a low pathogenicity serotype O9 strain of Yersinia enterocolitica results in a prolonged intestinal infection with colonization of Peyer's patches. Pretreatment with C4 was without effect on fecal excretion of yersiniae, but shortened the colonization of Peyer's patches. This protective effect was associated with pro-inflammatory status in the intestinal mucosa (TNF-α production in infected mice was increased by C4) and an increase in total IgA secretion. At a systemic level, C4 did not promote a pro-inflammatory response, although production of the immunoregulatory cytokine IFN-γ was enhanced. These findings suggest that L. plantarum C4 can increase resistance to intestinal infections through its immunomodulatory activity. Copyright © 2015 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

Effect of sampling and short isolation methodologies on the recovery of human pathogenic Yersinia enterocolitica from pig tonsils.

PubMed

Van Damme, Inge; Berkvens, Dirk; De Zutter, Lieven

2012-07-01

The objective of this study was to determine the effect of sampling (swab samples compared to destructive samples) on isolation rates of human pathogenic Yersinia enterocolitica from pig tonsils. Moreover, the relative efficiency of different rapid, routinely applicable isolation methods was evaluated. Therefore, swab and destructive samples from tonsils of 120 pigs at slaughter were analyzed in parallel using direct plating and different enrichment methods. Salmonella-Shigella-desoxycholate-calcium chloride (SSDC) agar, cefsulodin-irgasan-novobiocin (CIN) agar, and Yersinia enterocolitica chromogenic medium (YeCM) were used as selective agar media. For enrichment, irgasan-ticarcillin-potassium chlorate (ITC) broth and peptone-sorbitol-bile (PSB) broth were incubated at 25°C for 48 h. Overall, 55 tonsils (45.8%) were positive for Y. enterocolitica bioserotype 4/O:3. Recovery was significantly higher using the destructive method compared to the swabbing method. Direct plating resulted in 47 and 28 Y. enterocolitica-positive destructive and swab samples, respectively. Alkali treatment of PSB and ITC enrichment broths significantly increased recovery of pathogenic Y. enterocolitica from destructive tonsil samples. The performance of YeCM for qualitative and quantitative isolation of pathogenic Y. enterocolitica from pig tonsils was equal to SSDC and CIN. In conclusion, direct plating and ISO 10273: 2003 with minor modifications are suitable and rapid methods for isolation of pathogenic Y. enterocolitica from destructive tonsil samples.

Spondylodiscitis of the lumbar spine in a non-immunocompromised host caused by Yersinia enterocolitica O:9.

PubMed

Ellenrieder, Martin; Zautner, Andreas E; Podbielski, Andreas; Bader, Rainer; Mittelmeier, Wolfram

2010-04-01

Here presented is an extremely rare case of a spinal osteomyelitis (L5-S1) with epidural empyema in a non-immunocompromised 62-year-old man caused by Yersinia enterocolitica O:9. The infection occurred acutely and required immediate surgical treatment. Y. enterocolitica was cultured from the empyema fluid, wound swabs of the intervertebral disc L5-S1 and stool cultures. Following the surgical decompression and antibiotic treatment, the patient recovered completely, without neurological deficits. A review of the literature revealed only sparse cases of spondylodiscitis due to other Y. enterocolitica serogroups. To our knowledge, we report here the first case of a spondylodiscitis of the lumbar spine caused by Y. enterocolitica serovar O:9 in a non-immunocompromised patient.

Combined detection and strain typing of Yersinia enterocolitica directly from pork and poultry enrichments

USDA-ARS?s Scientific Manuscript database

Introduction: Yersinia enterocolitica is responsible for an estimated 98,000 cases of foodborne illness per year in the U.S. causing both intestinal and extraintestinal diseases. Its prevalence in retail pork and poultry, believed to the primary sources of these infections, ranges widely from 0 to 6...

A recombinant bivalent fusion protein rVE confers active and passive protection against Yersinia enterocolitica infection in mice.

PubMed

Singh, Amit Kumar; Kingston, Joseph Jeyabalaji; Murali, Harishchandra Sripathy; Batra, Harsh Vardhan

2014-03-05

In the present study, a bivalent chimeric protein rVE comprising immunologically active domains of Yersinia pestis LcrV and YopE was assessed for its prophylactic abilities against Yersinia enterocolitica O:8 infection in murine model. Mice immunized with rVE elicited significantly higher antibody titers with substantial contribution from the rV component (3:1 ratio). Robust and significant resistance to Y. enterocolitica infection with 100% survival (P<0.001) was seen in rVE vaccinated mice when intra peritoneal (I.P.) challenged with 10(8)CFU of Y. enterocolitica O:8 against the 75%, 60% and 75% survival seen in mice immunized with rV, rE, rV+rE, respectively. Macrophage monolayer supplemented with anti-rVE polysera illustrated efficient protection (89.41% survival) against challenge of Y. enterocolitica O:8. In contrast to sera from sham-immunized mice, immunization with anti-rVE polysera provided complete protection to BALB/c mice against I.P. challenge with 10(8)CFU of Y. enterocolitica O:8 and developed no conspicuous signs of infection in necropsy. The histopathological analysis of microtome sections confirmed significantly reduced lesion size or no lesion in liver and intestine upon infection in anti-rVE immunized mice. The findings from this study demonstrated the fusion protein rVE as a potential candidate subunit vaccine and showed the functional role of antibodies in protection against Y. enterocolitica infections. Copyright © 2014 Elsevier Ltd. All rights reserved.

Differentiation of the serological response to Yersinia enterocolitica and Brucella abortus in cattle

PubMed Central

Corbel, M. J.; Cullen, G. A.

1970-01-01

The serological responses of cattle to inoculation with Brucella abortus and Yersinia enterocolitica type IX were compared. Complete cross-reactions were found in serum agglutination, antiglobulin, complement fixation and Rose Bengal plate tests. The cross-reaction between Br. abortus and Y. enterocolitica IX was confirmed by immunodiffusion tests. Although antibodies specific for each organism could also be detected by immunodiffusion tests with high titre rabbit or bovine sera, these tests were insufficiently sensitive for routine diagnostic use. A quantitative Rose Bengal plate test, using Rose Bengal stained Br. abortus and Y. enterocolitica IX, was developed which enabled the antibody responses to the two organisms to be differentiated. The specificity of this test was confirmed by cross-absorption experiments and its sensitivity was sufficient to permit evaluation of all bovine sera giving positive reactions to the serum agglutination test. ImagesFig. 1Fig. 2 PMID:4992575

Analysis of Yersinia enterocolitica Effector Translocation into Host Cells Using Beta-lactamase Effector Fusions.

PubMed

Wolters, Manuel; Zobiak, Bernd; Nauth, Theresa; Aepfelbacher, Martin

2015-10-13

Many gram-negative bacteria including pathogenic Yersinia spp. employ type III secretion systems to translocate effector proteins into eukaryotic target cells. Inside the host cell the effector proteins manipulate cellular functions to the benefit of the bacteria. To better understand the control of type III secretion during host cell interaction, sensitive and accurate assays to measure translocation are required. We here describe the application of an assay based on the fusion of a Yersinia enterocolitica effector protein fragment (Yersinia outer protein; YopE) with TEM-1 beta-lactamase for quantitative analysis of translocation. The assay relies on cleavage of a cell permeant FRET dye (CCF4/AM) by translocated beta-lactamase fusion. After cleavage of the cephalosporin core of CCF4 by the beta-lactamase, FRET from coumarin to fluorescein is disrupted and excitation of the coumarin moiety leads to blue fluorescence emission. Different applications of this method have been described in the literature highlighting its versatility. The method allows for analysis of translocation in vitro and also in in vivo, e.g., in a mouse model. Detection of the fluorescence signals can be performed using plate readers, FACS analysis or fluorescence microscopy. In the setup described here, in vitro translocation of effector fusions into HeLa cells by different Yersinia mutants is monitored by laser scanning microscopy. Recording intracellular conversion of the FRET reporter by the beta-lactamase effector fusion in real-time provides robust quantitative results. We here show exemplary data, demonstrating increased translocation by a Y. enterocolitica YopE mutant compared to the wild type strain.

Yersinia enterocolitica : a review of its role in food hygiene.

PubMed

Morris, G K; Feeley, J C

1976-01-01

Since Yersinia enterocolitica, now classified as a member of the Enterobacteriaceae, was recognized as a distinct species in 1964 it has been isolated with increasing frequency from man and animals (including dogs and pigs) and from some human foods. Y. enterocolitica infections are now seen as a cause for some concern in both human and veterinary medicine. The organism is commonly found in specimens from swine slaughterhouses and has been isolated from samples of market meat, vacuum-packed beef, mussels, oysters, and ice-cream. It has also been found in nonchlorinated well water used for drinking purposes. Infections in man therefore probably have an alimentary origin. Only 23 human infections were recorded in 1966 but the number increased to over 4000 in 1974. However, reported incidence is affected by growing awareness about the role of the organism in human and animal disease and by intensive laboratory analyses. While knowledge about the geographical distribution of Y. enterocolitica is still fragmentary it is clear that infections are very frequent in some parts of the world and probably common but unrecognized in many countries. The most common symptoms of Y. enterocolitica infections in man are fever, abdominal pain, and diarrhoea. In the USA most isolations in human infections were made from blood and mesenteric lymph node samples. The pathogenic mechanism is not known. In one experiment involving a human volunteer subject a dose of 3.5 x 10(9) organisms was required to produce an infection. Only recently has some success been obtained in establishing experimental infections in mice, guinea-pigs, rats, and rabbits. Laboratory cultivation techniques for Y. enterocolitica are described together with a table of minimal tests for characterizing the organism and two biotyping schema. Little is known about methods for controlling this disease, but environmental hygiene and sanitation with regard to food and water should apply.

Prevalence of Yersinia enterocolitica Bioserotype 3/O:3 among Children with Diarrhea, China, 2010-2015.

PubMed

Duan, Ran; Liang, Junrong; Zhang, Jing; Chen, Yuhuang; Wang, Jing; Tong, Jing; Guo, Bangcheng; Hu, Wanfu; Wang, Mingliu; Zhao, Jiayong; Liu, Chang; Hao, Huijing; Wang, Xin; Jing, Huaiqi

2017-09-01

Yersinia enterocolitica is thought to not significantly contribute to diarrheal disease in China, but evidence substantiating this claim is limited. We determined the prevalence of Y. enterocolitica infection and strain types present among children <5 years of age with diarrhea in China. The overall prevalence of pathogenic isolates was 0.59%. Prevalence of pathogenic bioserotype 3/O:3 varied geographically. In this population, the presence of fecal leukocytes was a characteristic of Y. enterocolitica infection and should be used as an indication for microbiological diagnostic testing, rather than for the diagnosis of bacillary dysentery. In contrast with Y. enterocolitica isolates from adults, which were primarily biotype 1A, isolates from children were primarily bioserotype 3/O:3. Most pathogenic isolates from children shared pulsed-field gel electrophoresis patterns with isolates from pigs and dogs, suggesting a possible link between isolates from animals and infections in children. Our findings underscore the need for improved diagnostics for this underestimated pathogen.

Functional characterization of Gne (UDP-N-acetylglucosamine-4-epimerase), Wzz (chain length determinant), and Wzy (O-antigen polymerase) of Yersinia enterocolitica serotype O:8.

PubMed

Bengoechea, José Antonio; Pinta, Elise; Salminen, Tiina; Oertelt, Clemens; Holst, Otto; Radziejewska-Lebrecht, Joanna; Piotrowska-Seget, Zofia; Venho, Reija; Skurnik, Mikael

2002-08-01

The lipopolysaccharide (LPS) O-antigen of Yersinia enterocolitica serotype O:8 is formed by branched pentasaccharide repeat units that contain N-acetylgalactosamine (GalNAc), L-fucose (Fuc), D-galactose (Gal), D-mannose (Man), and 6-deoxy-D-gulose (6d-Gul). Its biosynthesis requires at least enzymes for the synthesis of each nucleoside diphosphate-activated sugar precursor; five glycosyltransferases, one for each sugar residue; a flippase (Wzx); and an O-antigen polymerase (Wzy). As this LPS shows a characteristic preferred O-antigen chain length, the presence of a chain length determinant protein (Wzz) is also expected. By targeted mutagenesis, we identify within the O-antigen gene cluster the genes encoding Wzy and Wzz. We also present genetic and biochemical evidence showing that the gene previously called galE encodes a UDP-N-acetylglucosamine-4-epimerase (EC 5.1.3.7) required for the biosynthesis of the first sugar of the O-unit. Accordingly, the gene was renamed gne. Gne also has some UDP-glucose-4-epimerase (EC 5.1.3.2) activity, as it restores the core production of an Escherichia coli K-12 galE mutant. The three-dimensional structure of Gne was modeled based on the crystal structure of E. coli GalE. Detailed structural comparison of the active sites of Gne and GalE revealed that additional space is required to accommodate the N-acetyl group in Gne and that this space is occupied by two Tyr residues in GalE whereas the corresponding residues present in Gne are Leu136 and Cys297. The Gne Leu136Tyr and Cys297Tyr variants completely lost the UDP-N-acetylglucosamine-4-epimerase activity while retaining the ability to complement the LPS phenotype of the E. coli galE mutant. Finally, we report that Yersinia Wzx has relaxed specificity for the translocated oligosaccharide, contrary to Wzy, which is strictly specific for the O-unit to be polymerized.

Prevalence of Yersinia enterocolitica Bioserotype 3/O:3 among Children with Diarrhea, China, 2010–2015

PubMed Central

Duan, Ran; Liang, Junrong; Zhang, Jing; Chen, Yuhuang; Tong, Jing; Guo, Bangcheng; Hu, Wanfu; Wang, Mingliu; Zhao, Jiayong; Liu, Chang; Hao, Huijing

2017-01-01

Yersinia enterocolitica is thought to not significantly contribute to diarrheal disease in China, but evidence substantiating this claim is limited. We determined the prevalence of Y. enterocolitica infection and strain types present among children <5 years of age with diarrhea in China. The overall prevalence of pathogenic isolates was 0.59%. Prevalence of pathogenic bioserotype 3/O:3 varied geographically. In this population, the presence of fecal leukocytes was a characteristic of Y. enterocolitica infection and should be used as an indication for microbiological diagnostic testing, rather than for the diagnosis of bacillary dysentery. In contrast with Y. enterocolitica isolates from adults, which were primarily biotype 1A, isolates from children were primarily bioserotype 3/O:3. Most pathogenic isolates from children shared pulsed-field gel electrophoresis patterns with isolates from pigs and dogs, suggesting a possible link between isolates from animals and infections in children. Our findings underscore the need for improved diagnostics for this underestimated pathogen. PMID:28820132

Evaluation of rapid SYS system as screen for Yersinia enterocolitica in the United States.

PubMed Central

Mele, L; Nadler, H; Gomez, S

1987-01-01

Clinical isolates (n = 150) from stool specimens were selected for evaluation of the Rapid SYS system (Analytab Products, Plainview, N.Y.) as a screening test for Shigella spp., Yersinia enterocolitica, and Salmonella spp. The Gram-Negative Identification Card (Vitek Systems, Inc., Hazelwood, Mo.) was used for identification. Although acceptable performance of the Rapid SYS system was described, the interpretative criteria provided by the vendor for previous studies led to inappropriate screening for Y. enterocolitica, particularly biotype 1. When corrected screening criteria were used for the present study, the sensitivity for the detection of 76 enteric pathogens was 98.7%. Of the 76 pathogens, 1 of 21 Shigella spp. was not detected. However, specificity was only 16.6% when 72 selected nonpathogens frequently encountered in stools were eliminated. Although the Rapid SYS system can identify Shigella spp., Y. enterocolitica, and Salmonella spp., only phenylalanine deaminase-producing and cytochrome oxidase-producing organisms can be eliminated from additional testing. Therefore, the Rapid SYS system cannot be used as a three-pathogen screen in the United States or in other geographic locales where Y. enterocolitica biotype 1 may be encountered. PMID:3323232

YersiniaBase: a genomic resource and analysis platform for comparative analysis of Yersinia.

PubMed

Tan, Shi Yang; Dutta, Avirup; Jakubovics, Nicholas S; Ang, Mia Yang; Siow, Cheuk Chuen; Mutha, Naresh Vr; Heydari, Hamed; Wee, Wei Yee; Wong, Guat Jah; Choo, Siew Woh

2015-01-16

Yersinia is a Gram-negative bacteria that includes serious pathogens such as the Yersinia pestis, which causes plague, Yersinia pseudotuberculosis, Yersinia enterocolitica. The remaining species are generally considered non-pathogenic to humans, although there is evidence that at least some of these species can cause occasional infections using distinct mechanisms from the more pathogenic species. With the advances in sequencing technologies, many genomes of Yersinia have been sequenced. However, there is currently no specialized platform to hold the rapidly-growing Yersinia genomic data and to provide analysis tools particularly for comparative analyses, which are required to provide improved insights into their biology, evolution and pathogenicity. To facilitate the ongoing and future research of Yersinia, especially those generally considered non-pathogenic species, a well-defined repository and analysis platform is needed to hold the Yersinia genomic data and analysis tools for the Yersinia research community. Hence, we have developed the YersiniaBase, a robust and user-friendly Yersinia resource and analysis platform for the analysis of Yersinia genomic data. YersiniaBase has a total of twelve species and 232 genome sequences, of which the majority are Yersinia pestis. In order to smooth the process of searching genomic data in a large database, we implemented an Asynchronous JavaScript and XML (AJAX)-based real-time searching system in YersiniaBase. Besides incorporating existing tools, which include JavaScript-based genome browser (JBrowse) and Basic Local Alignment Search Tool (BLAST), YersiniaBase also has in-house developed tools: (1) Pairwise Genome Comparison tool (PGC) for comparing two user-selected genomes; (2) Pathogenomics Profiling Tool (PathoProT) for comparative pathogenomics analysis of Yersinia genomes; (3) YersiniaTree for constructing phylogenetic tree of Yersinia. We ran analyses based on the tools and genomic data in YersiniaBase and the

Detection and characterisation of Yersinia enterocolitica strains in cold-stored carcasses of large game animals in Poland.

PubMed

Bancerz-Kisiel, Agata; Socha, Piotr; Szweda, Wojciech

2016-02-01

Yersinia enterocolitica is an important foodborne pathogen. The aim of the present study was to identify the bioserotypes and virulence markers of Y.enterocolitica strains isolated from three different anatomical regions of cold-stored carcasses of large game animals intended for human consumption. Y.enterocolitica strains were found in 12/20 (60%) of the roe deer carcasses examined, 7/16 (43.8%) of red deer carcasses and 11/20 (55%) of wild boar carcasses. Of the 52 Y.enterocolitica strains, 19 were isolated from the perineum, followed by 17 strains from the peritoneum of the longissimus dorsi muscle and 16 from the tonsils. Only one strain was isolated from warm culture. Bioserotype 1A/NI was the most commonly found and was detected in 29/52 isolates. All isolates contained amplicons corresponding to ystB gene fragments. The relatively high degree of carcass contamination with Y.enterocolitica is of concern due to the growing popularity of game meat with consumers. Copyright © 2015 Elsevier Ltd. All rights reserved.

Bacteriophages reduce Yersinia enterocolitica contamination of food and kitchenware.

PubMed

Jun, Jin Woo; Park, Se Chang; Wicklund, Anu; Skurnik, Mikael

2018-04-20

Yersinia enterocolitica, the primary cause of yersiniosis, is one of the most important foodborne pathogens globally and is associated with the consumption of raw contaminated pork. In the current study, four virulent bacteriophages (phages), one of Podoviridae (fHe-Yen3-01) and three of Myoviridae (fHe-Yen9-01, fHe-Yen9-02, and fHe-Yen9-03), capable of infecting Y. enterocolitica were isolated and characterized. fHe-Yen9-01 had the broadest host range (61.3% of strains, 65/106). It demonstrated a latent period of 35 min and a burst size of 33 plaque-forming units/cell, and was found to have a genome of 167,773 bp with 34.79% GC content. To evaluate the effectiveness of phage fHe-Yen9-01 against Y. enterocolitica O:9 strain Ruokola/71, we designed an experimental model of the food market environment. Phage treatment after bacterial inoculation of food samples, including raw pork (4 °C, 72 h), ready-to-eat pork (26 °C, 12 h), and milk (4 °C, 72 h), prevented bacterial growth throughout the experiments, with counts decreasing by 1-3 logs from the original levels of 2-4 × 10 3  CFU/g or ml. Similarly, when artificially contaminated kitchen utensils, such as wooden and plastic cutting boards and knives, and artificial hands, were treated with phages for 2 h, bacterial growth was effectively inhibited, with counts decreasing by 1-2 logs from the original levels of ca 10 4  CFU/cm 2 or ml. To the best of our knowledge, this is the first report of the successful application of phages for the control of Y. enterocolitica growth in food and on kitchen utensils. Copyright © 2018 Elsevier B.V. All rights reserved.

An outbreak of Yersinia enterocolitica in a captive colony of African green monkeys (Chlorocebus aethiops sabaeus) in the Caribbean

USDA-ARS?s Scientific Manuscript database

Yersinia enterocolitica is a zoonotic gram-negative pathogen that causes mesenteric lymphadenitis, terminal ileitis, acute gastroenteritis, and septicemia in domestic animals and primates. In 2012, 46 captive African green monkeys (Chlorocebus aethiops sabaeus) died during an outbreak of acutely fat...

Bioserotypes and virulence markers of Y. enterocolitica strains isolated from roe deer (Capreolus capreolus) and red deer (Cervus elaphus).

PubMed

Bancerz-Kisiel, A; Szczerba-Turek, A; Platt-Samoraj, A; Socha, P; Szweda, W

2014-01-01

Free-living animals are an important environmental reservoir of pathogens dangerous for other animal species and humans. One of those is Yersinia (Y.) enterocolitica, the causative agent of yersiniosis--foodborne, enzootic disease, significant for public health. The purpose of the study was to identify bioserotypes and virulence markers of Y enterocolitica strains isolated from roe deer (Capreolus capreolus) and red deer (Cervus elaphus) obtained during the 2010/2011 hunting season in north-eastern Poland. From among 48 rectal swabs obtained from 24 roe deer, two strains of Y enterocolitica from one animal were isolated. Although both belonged to biotype 1A they were identified as different serotypes. The strain obtained from cold culture (PSB) belonged to serotype 0:5, while the strain isolated from warm culture (ITC) was regarded as nonidentified (NI), what may suggest mixed infection in that animal. The presence of ystB gene, coding for YstB enterotoxin, directly related to Y enterocolitica pathogenicity was detected in both strains using triplex PCR. The effect of the examination of 32 swabs obtained from 16 red deer was the isolation of two Y enterocolitica strains from two different animals. Both belonged to biotype 1A with NI serotype, but were originated from different types of culture. They gave positive results in case of products of a size corresponding to the ystB gene. No amplicons corresponding to ail and ystA genes were found. Roe deer and red deer may carry and shed Y. enterocolitica, what seems to be important in aspect of an environmental reservoir of this pathogen. The Y enterocolitica strains isolated from wild ruminants had the amplicons of the ystB gene, what suggest they can be potential source of Y enterocolitica infection for humans.

[Two Outbreaks of Yersinia enterocolitica O:8 Infections in Tokyo and the Characterization of Isolates].

PubMed

Konishi, Noriko; Ishitsuka, Rie; Yokoyama, Keiko; Saiki, Dai; Akase, Satoru; Monma, Chie; Hirai, Akihiko; Sadamasu, Kenji; Kai, Akemi

2016-01-01

Although the number of outbreaks caused by Yersinia enterocolitica has been very small in Japan, 4 outbreaks were occurred during the 2 years between 2012 and 2013. We describe herein 2 outbreaks which were examined in Tokyo in the present study. Outbreak 1: A total of 39 people (37 high school students and 2 staff) stayed at a hotel in mountain area in Japan had experienced abdominal pain, diarrhea and fever in August, 2012. The Y. enterocolitica serogroup O:8 was isolated from 18 (64.3%) out of 28 fecal specimens of 28 patients. The infection roots could not be revealed because Y. enterocolitica was not detected from any meals at the hotel or its environment. Outbreak 2: A total of 52 students at a dormitory had diarrhea and fever in April, 2013. The results of the bacteriological and virological examinations of fecal specimens of patients showed that the Y. enterocolitica serogroup O:8 was isolated from 24 fecal specimens of 21 patients and 3 kitchen staff. We performed bacteriological and virological examination of the stored and preserved foods at the kitchen of the dormitory to reveal the suspect food. For the detection of Y. enterocolitica, food samples. together with phosphate buffered saline (PBS) were incubated at 4 degrees C for 21 days. Then, a screening test for Y. enterocolitica using realtime-PCR targeting the ail gene was performed against the PBS culture. One sample (fresh vegetable salad) tested was positive on realtime-PCR. No Y. enterocolitica was isolated on CIN agar from the PBS culture because many bacteria colonies other than Y. enterocolitica appeared on the CIN agar. After the alkaline-treatments of the culture broth or the immunomagnetic beads concentration method using anti-Y. enterocolitica O:8 antibodies, Y. enterocolitica O:8 which was the same serogroup as the patients' isolates was successfully isolated from the PBS culture. The fresh vegetable salad was confirmed as the incrimination food of this outbreak.

Polymorphisms in the lcrV gene of Yersinia enterocolitica and their effect on plague protective immunity.

PubMed

Miller, Nathan C; Quenee, Lauriane E; Elli, Derek; Ciletti, Nancy A; Schneewind, Olaf

2012-04-01

Current efforts to develop plague vaccines focus on LcrV, a polypeptide that resides at the tip of type III secretion needles. LcrV-specific antibodies block Yersinia pestis type III injection of Yop effectors into host immune cells, thereby enabling phagocytes to kill the invading pathogen. Earlier work reported that antibodies against Y. pestis LcrV cannot block type III injection by Yersinia enterocolitica strains and suggested that lcrV polymorphisms may provide for escape from LcrV-mediated plague immunity. We show here that polyclonal or monoclonal antibodies raised against Y. pestis KIM D27 LcrV (LcrV(D27)) bind LcrV from Y. enterocolitica O:9 strain W22703 (LcrV(W22703)) or O:8 strain WA-314 (LcrV(WA-314)) but are otherwise unable to block type III injection by Y. enterocolitica strains. Replacing the lcrV gene on the pCD1 virulence plasmid of Y. pestis KIM D27 with either lcrV(W22703) or lcrV(WA-314) does not affect the ability of plague bacteria to secrete proteins via the type III pathway, to inject Yops into macrophages, or to cause lethal plague infections in mice. LcrV(D27)-specific antibodies blocked type III injection by Y. pestis expressing lcrV(W22703) or lcrV(WA-314) and protected mice against intravenous lethal plague challenge with these strains. Thus, although antibodies raised against LcrV(D27) are unable to block the type III injection of Y. enterocolitica strains, expression of lcrV(W22703) or lcrV(WA-314) in Y. pestis did not allow these strains to escape LcrV-mediated plague protective immunity in the intravenous challenge model.

Evaluation of Chromogenic Medium for Selective Isolation of Yersinia.

PubMed

Thuan, Nguyen Khanh; Naher, Kamrun; Kubo, Ryoichi; Taniguchi, Takahide; Hayashidani, Hideki

2016-01-01

Cefsulodin-irgasan-novobiocin agar (CIN) has been used as a selective agar to detect Yersinia in food or human patients; however, its components can inhibit the growth of some strains of Yersinia enterocolitica serovar O3 and Y. pseudotuberculosis. Recently, a new Yersinia selective agar, CHROMagar Yersinia enterocolitica (CAYe), was developed and evaluated as a novel selective agar for pathogenic Y. enterocolitica. In this research, a total of 251Yersinia strains (176 pathogenic Y. enterocolitica, 59 Y. pseudotuberculosis, and 16 non-pathogenic Yersinia) were cultured on both CIN and CAYe for comparison. Except for 10 of 104 pathogenic Y. enterocolitica O3 strains and 59 Y. pseudotuberculosis strains, 198 Yersinia isolates grew on both media after 48 hr of incubation at 32℃. Of the 10 pathogenic Y. enterocolitica O3 which could not grow on CIN or CAYe, 9 strains could not grow on CIN with supplements and 1 strain could not grow CAYe with supplements. Of 9 strains which did not grow on CIN with supplements, 3 strains could not grow on CIN without supplements. However, 1 strain which did not grow on CAYe with supplements could grow on CAYe without supplements. All of the Y. pseudotuberculosis strains could grow on CIN with/without supplements and on CAYe without supplements. The results indicate that the inhibition of the growth of Y. enterocolitica O3 on CIN is related to the components of CIN; however, the inhibition on CAYe appears to be related to the supplements in CAYe. Therefore, CAYe may be a more useful selective medium than CIN for pathogenic Y. enterocolitica .

Detection of Yersinia Enterocolitica Species in Pig Tonsils and Raw Pork Meat by the Real-Time Pcr and Culture Methods.

PubMed

Stachelska, M A

2017-09-26

The aim of the present study was to establish a rapid and accurate real-time PCR method to detect pathogenic Yersinia enterocolitica in pork. Yersinia enterocolitica is considered to be a crucial zoonosis, which can provoke diseases both in humans and animals. The classical culture methods designated to detect Y. enterocolitica species in food matrices are often very time-consuming. The chromosomal locus _tag CH49_3099 gene, that appears in pathogenic Y. enterocolitica strains, was applied as DNA target for the 5' nuclease PCR protocol. The probe was labelled at the 5' end with the fluorescent reporter dye (FAM) and at the 3' end with the quencher dye (TAMRA). The real-time PCR cycling parameters included 41 cycles. A Ct value which reached a value higher than 40 constituted a negative result. The developed for the needs of this study qualitative real-time PCR method appeared to give very specific and reliable results. The detection rate of locus _tag CH49_3099 - positive Y. enterocolitica in 150 pig tonsils was 85 % and 32 % with PCR and culture methods, respectively. Both the Real-time PCR results and culture method results were obtained from material that was enriched during overnight incubation. The subject of the study were also raw pork meat samples. Among 80 samples examined, 7 ones were positive when real-time PCR was applied, and 6 ones were positive when classical culture method was applied. The application of molecular techniques based on the analysis of DNA sequences such as the Real-time PCR enables to detect this pathogenic bacteria very rapidly and with higher specificity, sensitivity and reliability in comparison to classical culture methods.

Prevalence of virulent Yersinia enterocolitica in bulk raw milk and retail cheese in northern-west of Iran.

PubMed

Hanifian, Shahram; Khani, Sajjad

2012-04-02

To determine the prevalence of virulent Yersinia enterocolitica, 554 samples consisting of 354 bulk raw milks and 200 traditional cheeses were collected from different parts of Eastern-Azerbaijan province, during a 23-month period from 2008 to 2010. The occurrence of virulent strains of Y. enterocolitica in samples enriched in peptone sorbitol bile broth (PSBB) was evaluated via the detection of attachment invasion locus (ail) gene by PCR. The viability of virulent Y. enterocolitica in the PCR-positive samples was tested using conventional culture method and the isolates were confirmed by the second-phase ail-PCR. According to the results, 8.66% of total samples including 7.62% of bulk raw milks and 10.5% of raw milk cheeses were found ail-positive by PCR method; subsequently Y. enterocolitica was isolated by the culture method and confirmed by the second phase ail-PCR in 2.88% of total samples including 2.26% of raw milks and 4% of cheese samples. It was concluded that, a sample enrichment followed by ail-PCR was more sensitive and robust to detect and distinguish the virulent strains of Y. enterocolitica compared to the conventional culture method. Copyright © 2012 Elsevier B.V. All rights reserved.

PspG, a New Member of the Yersinia enterocolitica Phage Shock Protein Regulon

PubMed Central

Green, Rebecca C.; Darwin, Andrew J.

2004-01-01

The Yersinia enterocolitica phage shock protein (Psp) system is induced when the Ysc type III secretion system is produced or when only the YscC secretin component is synthesized. Some psp null mutants have a growth defect when YscC is produced and a severe virulence defect in animals. The Y. enterocolitica psp locus is made up of two divergently transcribed cistrons, pspF and pspABCDycjXF. pspA operon expression is dependent on RpoN (σ54) and the enhancer-binding protein PspF. Previous data indicated that PspF also controls at least one gene that is not part of the psp locus. In this study we describe the identification of pspG, a new member of the PspF regulon. Predicted RpoN-binding sites upstream of the pspA genes from different bacteria have a common divergence from the consensus sequence, which may be a signature of PspF-dependent promoters. The Y. enterocolitica pspG gene was identified because its promoter also has this signature. Like the pspA operon, pspG is positively regulated by PspF, negatively regulated by PspA, and induced in response to the production of secretins. Purified His6-PspF protein specifically interacts with the pspA and pspG control regions. A pspA operon deletion mutant has a growth defect when the YscC secretin is produced and a virulence defect in a mouse model of infection. These phenotypes were exacerbated by a pspG null mutation. Therefore, PspG is the missing component of the Y. enterocolitica Psp regulon that was previously predicted to exist. PMID:15262928

Absence of Toll-like receptor 4 signaling results in delayed Yersinia enterocolitica YopP-induced cell death of dendritic cells.

PubMed

Gröbner, Sabine; Schulz, Sebastian; Soldanova, Irena; Gunst, Dani S J; Waibel, Michaela; Wesselborg, Sebastian; Borgmann, Stefan; Autenrieth, Ingo B

2007-01-01

In an initial period (< or =4 h) Toll-like receptor 4 (TLR4) signaling is required for Yersinia enterocolitica YopP-induced dendritic cell (DC) death. Later (>4 h), DC die independent of TLR4 signaling. In TLR4-deficient DC caspase 8 cleavage is delayed, indicating that TLR4 signaling accelerates caspase 8 activation, leading to DC death.

Yersinia enterocolitica in slaughter pig tonsils: enumeration and detection by enrichment versus direct plating culture.

PubMed

Van Damme, Inge; Habib, Ihab; De Zutter, Lieven

2010-02-01

Tonsil samples from 139 slaughter pigs were examined for the presence of pathogenic Yersinia enterocolitica by enrichment procedures based on the standard method ISO 10273:2003. In addition, samples were tested by direct plating method to evaluate its efficiency compared to the enrichment culture methods and to quantify the level of contamination in porcine tonsils. In total, 52 samples (37.4%) were positive for pathogenic Y. enterocolitica, all belonging to bioserotype 4/O:3. Fifty out of the 52 positive samples (96.2%) were detected by direct plating. Enumeration showed an average concentration of 4.5 log(10) CFU g(-1) and 4.4 log(10) CFU g(-1) tonsil on Salmonella-Shigella-desoxycholate-calcium chloride (SSDC) and cefsulodin-irgasan-novobiocin (CIN) agar plates, respectively. The enrichment procedures recommended by the ISO 10273:2003 method were not optimal for the isolation of pathogenic Y. enterocolitica from pig tonsils: two days enrichment in irgasan-ticarcillin-potassium chlorate (ITC) broth resulted in an isolation rate of 84.6%, while 5 days enrichment in peptone-sorbitol-bile (PSB) broth recovered only 59.6% of positive samples. Reducing the enrichment time in PSB from 5 to 2 days resulted in a significantly higher recovery rate (94.2%) and might serve as an appropriate enrichment protocol for the isolation of pathogenic Y. enterocolitica from pig tonsils. Compared to enrichment culture methods, results based on direct plating can be obtained in a shorter time course and provide quantitative data that might be needed for further risk assessment studies.

[Evaluation of the usefulness of the agglutination test with Mangifera indica extract for the identification of pathogenic Yersinia enterocolitica strains].

PubMed

Kałuzewski, S; Gierczyński, R; Szych, J; Jagielski, M

1997-01-01

The study was performed on 137 Y. enterocolitica strains belonging to various serological groups, including 75 03 group strains isolated form human clinical material. The agglutination test on slides was carried out on this strains using Mangifera indica extract of own production. Agglutinating preparation obtained from the seeds of M. indica agglutinated Y. enterocolitica organisms possessing the pVY plasmid and CRMOX+ phenotype in dilutions to 1.56 micrograms/ml. In identification tests conducted parallelly agglutination solution was used in concentrations of 100 and 10 micrograms/ml. All clones of Y. enterocolitica from O3 group from cultures at 37 degrees C and with CRMOX+ phenotype possessing the pVY plasmid were agglutinated by the extract. Agglutination failed to develop in the cultures of these clones incubated at 25 degrees C. Yersinia clones not containing the pVY plasmid with CRMOX- phenotype were resistant to agglutination. The virulence plasmid was found in 44 out of 75 strains of Y. enterocolitica O3 and was identified by restriction analysis after plasmid DNA digestion with Eco RI enzyme. The obtained results agreed with those of Wauters et al. in 1995 and confirmed the opinion of these authors on the usefulness of the test with M. indica agglutinin for the identification of virulent Y. enterocolitica strains.

Genotypic and phenotypic virulence characteristics and antimicrobial resistance of Yersinia spp. isolated from meat and milk products.

PubMed

Özdemir, Fatma; Arslan, Seza

2015-06-01

A total of 300 food samples including 180 milk and 120 meat products have been examined for the presence of Yersinia spp. using the ISO 10273 and the cold enrichment method. The overall prevalence of Yersinia spp. was 84 (28%). Yersinia enterocolitica was isolated from 18 (6%) of the 300 samples. The other Yersinia species were detected in the samples Yersinia rohdei 15 (5%), Yersinia intermedia 14 (4.7%), Yersinia pseudotuberculosis 12 (4%), Yersinia ruckeri 12 (4%), Yersinia mollaretii 5 (1.7%), Yersinia bercovieri 4 (1.3%), and atypical Yersinia spp. 4 (1.3%). The conventionally identified Y. enterocolitica strains were also confirmed by the 16S rRNA gene sequencing. All Y. enterocolitica strains biotyped as 1A had negative results in the phenotypic virulence tests. The 84 Yersinia strains were also examined genotypically for the presence of virulence genes. None of the Y. enterocolitica and other Yersinia strains contained the ail, ystA, yadA, and virF except only 1 Y. intermedia and 2 Y. enterocolitica strains that were found to be positive for ystB. Antimicrobial resistance of 84 Yersinia to 16 antimicrobial agents was determined by the disk diffusion method. All strains were sensitive to tobramycine and imipenem while resistant to clindamycin. Although 84.5% of the strains were resistant to at least 3 or more antimicrobial agents, 64.3% of them were resistant to 4 or more antimicrobial agents. © 2015 Institute of Food Technologists®

Antagonistic effect of chosen lactic acid bacteria strains on Yersinia enterocolitica species in model set-ups, meat and fermented sausages.

PubMed

Gomółka-Pawlicka, M; Uradziński, J

2003-01-01

The present study was aimed at determining the influence of 15 strains of lactic acid bacteria on the growth of 8 Yersinia enterocolitica strains in model set-ups, and in meat and ageing fermented sausages. The investigations were performed within the framework of three alternate stages which differed in respect to the products studied, the number of Lactobacillus sp. strains and, partly, methodological approach. The ratio between lactic acid bacteria and Yersinia enterocolitica strains studied was, depending on the variant of experiment, 1:1, 1:2 and 2:1, respectively. The study also considered water activity (aw) and pH of the products investigated. The results suggest that all the lactic acid bacteria strains used within the framework of the model set-ups had antagonistic effect on all the Salmonella sp. strains. However, this ability was not observed with respect to of tested lactic acid bacteria strains in meat and fermented sausage. This ability was possessed by one of the strains investigated--Lactobacillus helveticus T 78. The temperature and time of the incubation of sausages, but not aw and pH, were found to have a distinct influence on the antagonistic interaction between the bacteria tested.

Purification and characterization of Yersinia enterocolitica and Yersinia pestis LcrV-cholera toxin A(2)/B chimeras.

PubMed

Tinker, Juliette K; Davis, Chadwick T; Arlian, Britni M

2010-11-01

Yersinia pestis is a virulent human pathogen and potential biological weapon. Despite a long history of research on this organism, there is no licensed vaccine to protect against pneumonic forms of Y. pestis disease. In the present study, plasmids were constructed to express cholera toxin A(2)/B chimeric molecules containing the LcrV protective antigen from Yersinia enterocolitica and Y. pestis. These chimeras were expressed and purified to high yields from the supernatant of transformed Escherichia coli. Western and GM(1) ELISA assays were used to characterize the composition, receptor-binding and relative stability of the LcrV-CTA(2)/B chimera in comparison to cholera toxin. In addition, we investigated the ability of the Y. pestis LcrV-CTA(2)/B chimera to bind to and internalize into cultured epithelial cells and macrophages by confocal microscopy. These studies indicate that the uptake and trafficking of the LcrV antigen from the chimera is comparable to the trafficking of native toxin. Together these findings report that stable, receptor-binding, non-toxic LcrV-cholera toxin A(2)/B chimeras can be expressed at high levels in E. coli and purified from the supernatant. In addition, the internalization of antigen in vitro reported here supports the development of these molecules as novel mucosal vaccine candidates. Copyright 2010 Elsevier Inc. All rights reserved.

Biochemical studies on WbcA, a sugar epimerase from Yersinia enterocolitica.

PubMed

Salinger, Ari J; Brown, Haley A; Thoden, James B; Holden, Hazel M

2015-10-01

Yersinia enterocolitica is a Gram-negative bacterium that causes yersiniosis, a zoonotic disease affecting the gastrointestinal tract of humans, cattle, and pigs, among others. The lipopolysaccharide of Y. enterocolitica O:8 contains an unusual sugar, 6-deoxy-d-gulose, which requires four enzymes for its biosynthesis. Here, we describe a combined structural and functional investigation of WbcA, which catalyzes the third step in the pathway, namely an epimerization about the C-3' carbon of a CDP-linked sugar. The structure of WbcA was determined to 1.75-Å resolution, and the model was refined to an overall R-factor of 19.5%. The fold of WbcA places it into the well-defined cupin superfamily of sugar epimerases. Typically, these enzymes contain both a conserved histidine and a tyrosine residue that play key roles in catalysis. On the basis of amino acid sequence alignments, it was anticipated that the "conserved" tyrosine had been replaced with a cysteine residue in WbcA (Cys 133), and indeed this was the case. However, what was not anticipated was the fact that another tyrosine residue (Tyr 50) situated on a neighboring β-strand moved into the active site. Site-directed mutant proteins were subsequently constructed and their kinetic properties analyzed to address the roles of Cys 133 and Tyr 50 in WbcA catalysis. This study emphasizes the continuing need to experimentally verify assumptions that are based solely on bioinformatics approaches. © 2015 The Protein Society.

Genomic Characterization of Sixteen Yersinia enterocolitica-Infecting Podoviruses of Pig Origin

PubMed Central

Salem, Mabruka

2018-01-01

Yersinia enterocolitica causes enteric infections in humans and animals. Human infections are often caused by contaminated pork meat. Y. enterocolitica colonizes pig tonsils and pigs secrete both the human pathogen and its specific bacteriophages into the stools. In this work, sixteen Y. enterocolitica—infecting lytic bacteriophages isolated from pig stools originating from several pig farms were characterized. All phages belong to the Podoviridae family and their genomes range between 38,391–40,451 bp in size. The overall genome organization of all the phages resembled that of T7-like phages, having 3–6 host RNA polymerase (RNAP)-specific promoters at the beginning of the genomes and 11–13 phage RNAP-specific promoters as well as 3–5 rho-independent terminators, scattered throughout the genomes. Using a ligation-based approach, the physical termini of the genomes containing direct terminal repeats of 190–224 bp were established. No genes associated with lysogeny nor any toxin, virulence factor or antibiotic resistance genes were present in the genomes. Even though the phages had been isolated from different pig farms the nucleotide sequences of their genomes were 90–97% identical suggesting that the phages were undergoing microevolution within and between the farms. Lipopolysaccharide was found to be the surface receptor of all but one of the phages. The phages are classified as new species within the T7virus genus of Autographivirinae subfamily. PMID:29614052

Enrichment, isolation, and virulence of freeze-stressed plasmid-bearing virulent strains of Yersinia enterocolitica on pork.

PubMed

Bhaduri, Saumya

2006-08-01

The influence of freeze stress at -20 degrees C on the enrichment, isolation, detection, presence of virulence plasmid, and expression of virulence of plasmid-bearing Yersinia enterocolitica (YEP+) inoculated on pork chop medallions was assessed. Pork chop medallions (10 cm2) artificially contaminated with 10, 1, and 0.5 CFU/cm2 of YEP+ strains (serotype O:3) were placed in sterile petri dishes at -20 degrees C for 24 h. The medallions were swabbed when frozen, after thawing at room temperature for 1.5 h and after thawing at 4 degrees C for 18 h. Swabs were enriched and YEP+ were detected and isolated using the Congo red-binding and low-calcium-response assays. The YEP+ were isolated under all conditions on pork chop medallions inoculated with 10 CFU/cm2 and at a level of 1 CFU/cm2 when thawed at room temperature and at 4 degrees C but not from frozen pork chop medallions. The YEP+ were not isolated from pork chop medallions inoculated with 0.5 CFU/cm2 and then frozen, whereas YEP+ were recovered when inoculated at this level from pork chop medallions not subjected to freezing. Virulence of the strains isolated from frozen pork chop medallions was confirmed by PCR and the expression of plasmid-associated phenotypes. These results indicate that YEP+ subjected to freezing on pork are potentially capable of causing foodborne illness and that freezing is not a substitute for safe handling and proper cooking of pork.

Evaluation of DNA colony hybridization and other techniques for detection of virulence in Yersinia species.

PubMed Central

Robins-Browne, R M; Miliotis, M D; Cianciosi, S; Miller, V L; Falkow, S; Morris, J G

1989-01-01

The virulence of yersiniae varies according to (i) species and biotype and (ii) possession of a 67- to 72-kilobase virulence plasmid. Y. pestis, Y. pseudotuberculosis, and biotypes 1B, 2, 3, 4, and 5 of Y. enterocolitica are inherently virulent but express full virulence only when in possession of a virulence plasmid. Other Yersinia species and biotypes 1A and 3B of Y. enterocolitica are seldom implicated in disease. In this study, we prepared DNA probes from eight nonoverlapping regions of the virulence plasmid of a strain of Y. enterocolitica and from the inv and ail chromosomal loci responsible for the invasive capacity of Y. enterocolitica and Y. pseudotuberculosis. The probes were used in colony hybridization experiments to investigate 156 yersiniae of various species and biotypes and of differing virulence. Probes prepared from the inv gene of Y. pseudotuberculosis hybridized with Y. pseudotuberculosis and Y. pestis only, whereas an analogous probe prepared from Y. enterocolitica hybridized with all species and biotypes of yersiniae (but not with other bacteria) regardless of virulence or potential virulence. Probes prepared from the ail region of Y. enterocolitica reacted almost exclusively with Y. enterocolitica strains of pathogenic biotypes. Probes prepared from the virulence plasmid of a serogroup O:8, biotype 1B isolate of Y. enterocolitica identified virulent yersiniae in all species with a high degree of sensitivity and specificity. These probes did not react with yersiniae of avirulent biotypes or species. Of the other assays of virulence evaluated (calcium dependence, binding of crystal violet, and pyrazinamidase activity), binding of crystal violet provided a simple means for identifying plasmid-bearing strains. Images PMID:2723033

Yersinia enterocolitica-Specific Infection by Bacteriophages TG1 and ϕR1-RT Is Dependent on Temperature-Regulated Expression of the Phage Host Receptor OmpF.

PubMed

Leon-Velarde, Carlos G; Happonen, Lotta; Pajunen, Maria; Leskinen, Katarzyna; Kropinski, Andrew M; Mattinen, Laura; Rajtor, Monika; Zur, Joanna; Smith, Darren; Chen, Shu; Nawaz, Ayesha; Johnson, Roger P; Odumeru, Joseph A; Griffiths, Mansel W; Skurnik, Mikael

2016-09-01

Bacteriophages present huge potential both as a resource for developing novel tools for bacterial diagnostics and for use in phage therapy. This potential is also valid for bacteriophages specific for Yersinia enterocolitica To increase our knowledge of Y. enterocolitica-specific phages, we characterized two novel yersiniophages. The genomes of the bacteriophages vB_YenM_TG1 (TG1) and vB_YenM_ϕR1-RT (ϕR1-RT), isolated from pig manure in Canada and from sewage in Finland, consist of linear double-stranded DNA of 162,101 and 168,809 bp, respectively. Their genomes comprise 262 putative coding sequences and 4 tRNA genes and share 91% overall nucleotide identity. Based on phylogenetic analyses of their whole-genome sequences and large terminase subunit protein sequences, a genus named Tg1virus within the family Myoviridae is proposed, with TG1 and ϕR1-RT (R1RT in the ICTV database) as member species. These bacteriophages exhibit a host range restricted to Y. enterocolitica and display lytic activity against the epidemiologically significant serotypes O:3, O:5,27, and O:9 at and below 25°C. Adsorption analyses of lipopolysaccharide (LPS) and OmpF mutants demonstrate that these phages use both the LPS inner core heptosyl residues and the outer membrane protein OmpF as phage receptors. Based on RNA sequencing and quantitative proteomics, we also demonstrate that temperature-dependent infection is due to strong repression of OmpF at 37°C. In addition, ϕR1-RT was shown to be able to enter into a pseudolysogenic state. Together, this work provides further insight into phage-host cell interactions by highlighting the importance of understanding underlying factors which may affect the abundance of phage host receptors on the cell surface. Only a small number of bacteriophages infecting Y. enterocolitica, the predominant causative agent of yersiniosis, have been previously described. Here, two newly isolated Y. enterocolitica phages were studied in detail, with the aim of

Yersinia enterocolitica-Specific Infection by Bacteriophages TG1 and ϕR1-RT Is Dependent on Temperature-Regulated Expression of the Phage Host Receptor OmpF

PubMed Central

Happonen, Lotta; Pajunen, Maria; Leskinen, Katarzyna; Kropinski, Andrew M.; Mattinen, Laura; Rajtor, Monika; Zur, Joanna; Smith, Darren; Chen, Shu; Nawaz, Ayesha; Johnson, Roger P.; Odumeru, Joseph A.; Griffiths, Mansel W.

2016-01-01

ABSTRACT Bacteriophages present huge potential both as a resource for developing novel tools for bacterial diagnostics and for use in phage therapy. This potential is also valid for bacteriophages specific for Yersinia enterocolitica. To increase our knowledge of Y. enterocolitica-specific phages, we characterized two novel yersiniophages. The genomes of the bacteriophages vB_YenM_TG1 (TG1) and vB_YenM_ϕR1-RT (ϕR1-RT), isolated from pig manure in Canada and from sewage in Finland, consist of linear double-stranded DNA of 162,101 and 168,809 bp, respectively. Their genomes comprise 262 putative coding sequences and 4 tRNA genes and share 91% overall nucleotide identity. Based on phylogenetic analyses of their whole-genome sequences and large terminase subunit protein sequences, a genus named Tg1virus within the family Myoviridae is proposed, with TG1 and ϕR1-RT (R1RT in the ICTV database) as member species. These bacteriophages exhibit a host range restricted to Y. enterocolitica and display lytic activity against the epidemiologically significant serotypes O:3, O:5,27, and O:9 at and below 25°C. Adsorption analyses of lipopolysaccharide (LPS) and OmpF mutants demonstrate that these phages use both the LPS inner core heptosyl residues and the outer membrane protein OmpF as phage receptors. Based on RNA sequencing and quantitative proteomics, we also demonstrate that temperature-dependent infection is due to strong repression of OmpF at 37°C. In addition, ϕR1-RT was shown to be able to enter into a pseudolysogenic state. Together, this work provides further insight into phage-host cell interactions by highlighting the importance of understanding underlying factors which may affect the abundance of phage host receptors on the cell surface. IMPORTANCE Only a small number of bacteriophages infecting Y. enterocolitica, the predominant causative agent of yersiniosis, have been previously described. Here, two newly isolated Y. enterocolitica phages were studied in

Comparative analysis of the Photorhabdus luminescens and the Yersinia enterocolitica genomes: uncovering candidate genes involved in insect pathogenicity

PubMed Central

Heermann, Ralf; Fuchs, Thilo M

2008-01-01

Background Photorhabdus luminescens and Yersinia enterocolitica are both enteric bacteria which are associated with insects. P. luminescens lives in symbiosis with soil nematodes and is highly pathogenic towards insects but not to humans. In contrast, Y. enterocolitica is widely found in the environment and mainly known to cause gastroenteritis in men, but has only recently been shown to be also toxic for insects. It is expected that both pathogens share an overlap of genetic determinants that play a role within the insect host. Results A selective genome comparison was applied. Proteins belonging to the class of two-component regulatory systems, quorum sensing, universal stress proteins, and c-di-GMP signalling have been analysed. The interorganismic synopsis of selected regulatory systems uncovered common and distinct signalling mechanisms of both pathogens used for perception of signals within the insect host. Particularly, a new class of LuxR-like regulators was identified, which might be involved in detecting insect-specific molecules. In addition, the genetic overlap unravelled a two-component system that is unique for the genera Photorhabdus and Yersinia and is therefore suggested to play a major role in the pathogen-insect relationship. Our analysis also highlights factors of both pathogens that are expressed at low temperatures as encountered in insects in contrast to higher (body) temperature, providing evidence that temperature is a yet under-investigated environmental signal for bacterial adaptation to various hosts. Common degradative metabolic pathways are described that might be used to explore nutrients within the insect gut or hemolymph, thus enabling the proliferation of P. luminescens and Y. enterocolitica in their invertebrate hosts. A strikingly higher number of genes encoding insecticidal toxins and other virulence factors in P. luminescens compared to Y. enterocolitica correlates with the higher virulence of P. luminescens towards insects

Structure of the metal-dependent deacetylase LpxC from Yersinia enterocolitica complexed with the potent inhibitor CHIR-090 .

PubMed

Cole, Kathryn E; Gattis, Samuel G; Angell, Heather D; Fierke, Carol A; Christianson, David W

2011-01-18

The first committed step of lipid A biosynthesis is catalyzed by UDP-(3-O-((R)-3-hydroxymyristoyl))-N-acetylglucosamine deacetylase, a metal-dependent deacetylase also known as LpxC. Because lipid A is essential for bacterial viability, the inhibition of LpxC is an appealing therapeutic strategy for the treatment of Gram-negative bacterial infections. Here we report the 1.79 Å resolution X-ray crystal structure of LpxC from Yersinia enterocolitica (YeLpxC) complexed with the potent hydroxamate inhibitor CHIR-090. This enzyme is a nearly identical orthologue of LpxC from Yersinia pestis (99.7% sequence identity), the pathogen that causes bubonic plague. Similar to the inhibition of LpxC from Escherichia coli, CHIR-090 inhibits YeLpxC via a two-step slow, tight-binding mechanism with an apparent K(i) of 0.54 ± 0.14 nM followed by conversion of the E·I to E·I* species with a rate constant of 0.11 ± 0.01 min(-1). The structure of the LpxC complex with CHIR-090 shows that the inhibitor hydroxamate group chelates the active site zinc ion, and the "tail" of the inhibitor binds in the hydrophobic tunnel in the active site. This hydrophobic tunnel is framed by a βαβ subdomain that exhibits significant conformational flexibility as it accommodates inhibitor binding. CHIR-090 displays a 27 mm zone of inhibition against Y. enterocolitica in a Kirby-Bauer antibiotic assay, which is comparable to its reported activity against other Gram-negative species including E. coli and Pseudomonas aeruginosa. This study demonstrates that the inhibition of LpxC should be explored as a potential therapeutic and/or prophylatic response to infection by weaponized Yersinia species.

Evaluation of a modified Cefsulodin-Irgasan-Novobiocin agar for isolation of Yersinia spp.

PubMed

Tan, Lai Kuan; Ooi, Peck Toung; Carniel, Elisabeth; Thong, Kwai Lin

2014-01-01

Y. enterocolitica and Y. pseudotuberculosis are important food borne pathogens. However, the presence of competitive microbiota makes the isolation of Y. enterocolitica and Y. pseudotuberculosis from naturally contaminated foods difficult. We attempted to evaluate the performance of a modified Cefsulodin-Irgasan-Novobiocin (CIN) agar in the differentiation of Y. enterocolitica from non-Yersinia species, particularly the natural intestinal microbiota. The modified CIN enabled the growth of Y. enterocolitica colonies with the same efficiency as CIN and Luria-Bertani agar. The detection limits of the modified CIN for Y. enterocolitica in culture medium (10 cfu/ml) and in artificially contaminated pork (10(4) cfu/ml) were also comparable to those of CIN. However, the modified CIN provided a better discrimination of Yersinia colonies from other bacteria exhibiting Yersinia-like colonies on CIN (H2S-producing Citrobacter freundii, C. braakii, Enterobacter cloacae, Aeromonas hydrophila, Providencia rettgeri, and Morganella morganii). The modified CIN exhibited a higher recovery rate of Y. enterocolitica from artificially prepared bacterial cultures and naturally contaminated samples compared with CIN. Our results thus demonstrated that the use of modified CIN may be a valuable means to increase the recovery rate of food borne Yersinia from natural samples, which are usually contaminated by multiple types of bacteria.

Resistance of chemokine receptor 6-deficient mice to Yersinia enterocolitica infection: evidence of defective M-cell formation in vivo.

PubMed

Westphal, Sabine; Lügering, Andreas; von Wedel, Julia; von Eiff, Christof; Maaser, Christian; Spahn, Thomas; Heusipp, Gerhard; Schmidt, M Alexander; Herbst, Hermann; Williams, Ifor R; Domschke, Wolfram; Kucharzik, Torsten

2008-03-01

M cells, specialized cells within Peyer's patches (PPs), are reduced in number in chemokine receptor 6 (CCR6)-deficient mice. The pathogenic microorganism Yersinia enterocolitica exploits M cells for the purpose of mucosal tissue invasion exclusively through PPs. The aim of this study was to evaluate the course of yersiniosis in CCR6-deficient mice and to investigate whether these mice might be used as an in vivo model to determine M-cell function. After oral challenge with Y. enterocolitica, control mice suffered from lethal septic infection whereas CCR6-deficient mice showed very limited symptoms of infection. Immunohistochemical analysis demonstrated PP invasion by Y. enterocolitica in control mice whereas no bacteria could be found in CCR6-deficient mice. In addition, a significant induction of proinflammatory cytokines could be found in control mice whereas proinflammatory cytokine levels in CCR6-deficient mice remained unchanged. In contrast, intraperitoneal infection resulted in severe systemic yersiniosis in both mouse groups. Abrogated oral Y. enterocolitica infection in CCR6-deficient mice demonstrates the importance of CCR6 expression in the physiological and pathological immune responses generated within PPs by influencing M-cell differentiation, underscoring the important role of M cells in the process of microbial uptake. CCR6-deficient mice may therefore represent a suitable model for the study of M-cell function in vivo.

Multiple-Locus Variable-Number Tandem-Repeat Analysis in Genotyping Yersinia enterocolitica Strains from Human and Porcine Origins

PubMed Central

Laukkanen-Ninios, R.; Ortiz Martínez, P.; Siitonen, A.; Fredriksson-Ahomaa, M.; Korkeala, H.

2013-01-01

Sporadic and epidemiologically linked Yersinia enterocolitica strains (n = 379) isolated from fecal samples from human patients, tonsil or fecal samples from pigs collected at slaughterhouses, and pork samples collected at meat stores were genotyped using multiple-locus variable-number tandem-repeat analysis (MLVA) with six loci, i.e., V2A, V4, V5, V6, V7, and V9. In total, 312 different MLVA types were found. Similar types were detected (i) in fecal samples collected from human patients over 2 to 3 consecutive years, (ii) in samples from humans and pigs, and (iii) in samples from pigs that originated from the same farms. Among porcine strains, we found farm-specific MLVA profiles. Variations in the numbers of tandem repeats from one to four for variable-number tandem-repeat (VNTR) loci V2A, V5, V6, and V7 were observed within a farm. MLVA was applicable for serotypes O:3, O:5,27, and O:9 and appeared to be a highly discriminating tool for distinguishing sporadic and outbreak-related strains. With long-term use, interpretation of the results became more challenging due to variations in more-discriminating loci, as was observed for strains originating from pig farms. Additionally, we encountered unexpectedly short V2A VNTR fragments and sequenced them. According to the sequencing results, updated guidelines for interpreting V2A VNTR results were prepared. PMID:23637293

[Biological properties of bacteriophages, active to Yersinia enterocolitica].

PubMed

Darsavelidze, M A; Kapanadze, Zh S; Chanishvili, T G

2004-01-01

The biological properties of 16 clones of Y. enterolitica bacteriophages were tested to select the most active for subsequent use. For the first time Y. enterocolitica virulent phages belonging to the family of Podoviridae were described and 7 serological groups of phages with no cross reactions were registered. The technology for the production of new therapeutic and prophylactic Y. enterocolitica polyvalent bacteriophage under laboratory conditions was developed. The effective multiplicity of contamination ensuring the maximum release of phages from bacterial cells, the optimum incubation temperature and the time of exposure were established. The experimental batches of therapeutic and prophylactic Y. enterocolitica polyvalent bacteriophage thus obtained met the requirements for antibacterial preparations.

Yersinia species in the dunnock (Prunella modularis) in sub-alpine habitats of the Western Carpathians.

PubMed

Kisková, Jana; Hrehová, Zuzana; Janiga, Marián; Lukán, Martin; Haas, Martina; Jurcovicová, Martina

2011-01-01

The study presents the prevalence of Yersinia species in dunnok Prunella modularis from the sub-alpine zone of the Western Carpathians. Bacteria were detected from cloacal and pharyngeal swabs from 97 specimens using PCR assay. Yersinia enterocolitica showed the highest prevalence (47.4%) from among the determined Yersinia species. Yersinia species (except Y frederiksenii) were detected more frequently in pharyngeal than cloacal samples. The highest prevalence of yersiniosis was detected in April (Yersinia spp. - 80%, Y. enterocolitica - 70%). No statistically differences were observed in the prevalence of Yersinia spp. between males and females and between juveniles and adult birds. Bacterial contamination did not affect body weight or tarsus length.

Prevalence of Listeria monocytogenes, Yersinia enterocolitica, Staphylococcus aureus, and Salmonella enterica Typhimurium in meat and meat products using multiplex polymerase chain reaction

PubMed Central

Latha, C.; Anu, C. J.; Ajaykumar, V. J.; Sunil, B.

2017-01-01

Aim: The objective of the study was to investigate the occurrence of Listeria monocytogenes, Yersinia enterocolitica, Staphylococcus aureus, and Salmonella enterica Typhimurium in meat and meat products using the multiplex polymerase chain reaction (PCR) method. Materials and Methods: The assay combined an enrichment step in tryptic soy broth with yeast extract formulated for the simultaneous growth of target pathogens, DNA isolation and multiplex PCR. A total of 1134 samples including beef (n=349), chicken (n=325), pork (n=310), chevon (n=50), and meat products (n=100) were collected from different parts of Kerala, India. All the samples were subjected to multiplex PCR analysis and culture-based detection for the four pathogens in parallel. Results: Overall occurrence of L. monocytogenes was 0.08 % by cultural method. However, no L. monocytogenes was obtained by multiplex PCR method. Yersinia enterocolitica was obtained from beef and pork samples. A high prevalence of S. aureus (46.7%) was found in all types of meat samples tested. None of the samples was positive for S. Typhimurium. Conclusion: Multiplex PCR assay used in this study can detect more than one pathogen simultaneously by amplifying more than one target gene in a single reaction, which can save time and labor cost. PMID:28919685

Detection of pathogenic Yersinia enterocolitica in foods and water by immunomagnetic separation, nested polymerase chain reactions, and colorimetric detection of amplified DNA.

PubMed Central

Kapperud, G; Vardund, T; Skjerve, E; Hornes, E; Michaelsen, T E

1993-01-01

A two-step polymerase chain reaction (PCR) procedure with two nested pairs of primers specific for the yadA gene of Yersinia enterocolitica was developed. The PCR assay identified all common pathogenic serogroups (O:3, O:5,27, O:8, O:9, O:13, and O:21) from three continents and differentiated pathogenic Y. enterocolitica from Y. pseudotuberculosis and from a variety of nonpathogenic yersiniae representing 25 serogroups and four species. The performance of the method was evaluated with seeded food and water samples. We compared two procedures for sample preparation prior to PCR: one was based on immunomagnetic separation of the target bacteria from the sample, using magnetic particles coated with immunoglobulin antibodies to Y. enterocolitica serogroup O:3, and the other method consisted of a series of centrifugation steps combined with proteinase treatment. Regardless of the method used, the PCR assay was capable of detecting 10 to 30 CFU/g of meat in 10(6)-fold excess of indigenous bacteria. When the samples were enriched overnight in a nonselective medium, the sensitivity was increased to approximately 2 CFU/g, except for samples with an extremely high background flora (> 10(7) CFU/g). We compared gel electrophoretic detection of PCR products with a colorimetric detection method designated DIANA (detection of immobilized amplified nucleic acids), which enabled easy visualization of amplified fragments in a microtiter plate format with an optical density reader. DIANA and gel electrophoresis showed complete concordance in their discrimination between positive and negative samples. The combination of immunomagnetic separation, nested PCR, and DIANA makes possible the development of a fully automated analytic process which requires a minimum of laboratory manipulations. Images PMID:8215366

Effects of essential oils of oregano and nutmeg on growth and survival of Yersinia enterocolitica and Listeria monocytogenes in barbecued chicken.

PubMed

Firouzi, R; Shekarforoush, S S; Nazer, A H K; Borumand, Z; Jooyandeh, A R

2007-11-01

The in vitro effects of plant essential oils (EOs) against pathogenic bacteria are well known, yet few studies have addressed the effects of these compounds against pathogens associated with ready-to-cook foods. Experiments were conducted to determine the effectiveness of oregano and nutmeg EOs on the growth and survival of Yersinia enterocolitica and Listeria monocytogenes in broth culture and in Iranian barbecued chicken. Ready-to-cook Iranian barbecued chicken was prepared according to the common practice with 1, 2, and 3 microl/g of oregano and nutmeg EOs. The test and control (without EOs) samples were inoculated with Y. enterocolitica and L. monocytogenes to a final concentration of 6 to 7 log CFU/g and stored at 3, 8, and 20 degrees C. Microorganisms were counted just before and at 24, 48, and 72 h after storage based on growth on Yersinia selective agar supplemented with cefsulodine, igrasan, and novobiocin and on Listeria selective agar supplemented with nalidixic acid and acriflavin. In the broth culture system, the nutmeg EO had a greater effect on L. monocytogenes (MIC = 0.20 nicrol/ml) than did the oregano EO (MIC = 0.26 microl/ml). However, the oregano EO had a greater effect on Y. enterocolitica (MIC = 0.16 microl/ml) than did the nutmeg EO (MIC = 0.25 microl/ml). In ready-to-cook Iranian barbecued chicken, the log CFU per gram of both bacteria after up to 72 h of incubation was not decreased significantly by various combinations of oregano and nutmeg EOs (1, 2, and 3 microl/g) and storage temperatures (3, 8, and 20 degrees C) when compared with control samples (without EOs). Although examination of spices in culture media can yield accurate microbiological data, without complementary tests in foods these data are of limited value for assessing food safety.

Canis lupus familiaris involved in the transmission of pathogenic Yersinia spp. in China.

PubMed

Wang, Xin; Liang, Junrong; Xi, Jinxiao; Yang, Jinchuan; Wang, Mingliu; Tian, Kecheng; Li, Jicheng; Qiu, Haiyan; Xiao, Yuchun; Duan, Ran; Yang, Haoshu; Li, Kewei; Cui, Zhigang; Qi, Meiying; Jing, Huaiqi

2014-08-06

To investigate canines carrying pathogens associated with human illness, we studied their roles in transmitting and maintaining pathogenic Yersinia spp. We examined different ecological landscapes in China for the distribution of pathogenic Yersinia spp. in Canis lupus familiaris, the domestic dog. The highest number of pathogenic Yersinia enterocolitica was shown from the tonsils (6.30%), followed by rectal swabs (3.63%) and feces (1.23%). Strains isolated from plague free areas for C. lupus familiaris, local pig and diarrhea patients shared the same pulsed-field gel electrophoresis (PFGE) pattern, indicating they may be from the same clone and the close transmission source of pathogenic Y. enterocolitica infections in these areas. Among 226 dogs serum samples collected from natural plague areas of Yersinia pestis in Gansu and Qinghai Provinces, 49 were positive for F1 antibody, while the serum samples collected from plague free areas were all negative, suggested a potential public health risk following exposure to dogs. No Y. enterocolitica or Yersinia pseudotuberculosis was isolated from canine rectal swabs in natural plague areas. Therefore, pathogenic Yersinia spp. may be regionally distributed in China. Copyright © 2014 Elsevier B.V. All rights reserved.

Sheep carrying pathogenic Yersinia enterocolitica bioserotypes 2/O:9 and 5/O:3 in the feces at slaughter.

PubMed

Joutsen, Suvi; Eklund, Kirsi-Maria; Laukkanen-Ninios, Riikka; Stephan, Roger; Fredriksson-Ahomaa, Maria

2016-12-25

Yersinia enterocolitica is a heterogeneous species including non-pathogenic strains belonging to biotype 1A and pathogenic strains belonging to biotypes 1B and 2-5. Pathogenic strains of biotypes 2-4 carrying the ail virulence gene have frequently been isolated from domestic pigs at slaughter. In sheep, mostly non-pathogenic biotype 1A strains have been reported. In our study, the prevalence of ail-positive Y. enterocolitica was studied by PCR and culturing in 406 young sheep (<1year of age) and 139 older sheep at slaughter in Finland. When using PCR, the detection rate was 11% (45/406) in young sheep originating from 11 (18%) farms. Surprisingly, Y. enterocolitica belonging to bioserotypes 2/O:9 and 5/O:3, carrying both chromosomal and plasmid-borne virulence genes, were isolated from the fecal samples of 10 (2%) and 23 (4%) sheep, respectively. All isolates of bioserotypes 2/O:9 (19 isolates) and 5/O:3 (53 isolates) carried the chromosomal virulence genes ail, inv, ystA, and myfA, and almost all isolates (71/72) also carried the virulence genes virF and yadA located on the virulence plasmid. The isolates showed high susceptibility to tested antimicrobials and low genetic diversity by PFGE. Y. enterocolitica bioserotype 5/O:3 is a very rare bioserotype, and has earlier only sporadically been reported in European wildlife and in sheep in Australia and New Zealand. Bioserotype 2/O:9 is a common bioserotype found in humans with yersiniosis, and has sporadically been isolated in wild and domestic animals. Copyright © 2016 Elsevier B.V. All rights reserved.

Genotyping of Yersinia enterocolitica biotype 1A strains from clinical and nonclinical origins by pulsed-field gel electrophoresis.

PubMed

Campioni, Fábio; Falcão, Juliana P

2014-06-01

Yersinia enterocolitica biotype 1A (B1A) strains are considered mainly nonpathogenic. However, some studies considered strains of this biotype to be the causal agents of infections in humans and animals. In South America, there are no studies that have compared clinical and nonclinical strains of B1A typed by pulsed-field gel electrophoresis (PFGE) and none that have compared the capability of different enzymes on typing these strains. This study typed 51 Y. enterocolitica B1A strains isolated in Brazil and Chile by PFGE, testing the enzymes XbaI, NotI, and XhoI. The resulting dendrograms discriminated the strains in 47, 40, and 49 pulsotypes generated by the cleavage with the enzymes XbaI, NotI, and XhoI, respectively. The majority of the strains were grouped independently of their clinical or nonclinical origins. The high discriminatory power of PFGE confirmed the heterogeneity of B1A strains but could not divide the strains studied into clusters that differed in the frequency of some virulence genes as observed in studies using other methodologies.

Murine Neonates Infected with Yersinia enterocolitica Develop Rapid and Robust Proinflammatory Responses in Intestinal Lymphoid Tissues

PubMed Central

Siefker, David T.; Echeverry, Andrea; Brambilla, Roberta; Fukata, Masayuki; Schesser, Kurt

2014-01-01

Neonatal animals are generally very susceptible to infection with bacterial pathogens. However, we recently reported that neonatal mice are highly resistant to orogastric infection with Yersinia enterocolitica. Here, we show that proinflammatory responses greatly exceeding those in adults arise very rapidly in the mesenteric lymph nodes (MLN) of neonates. High-level induction of proinflammatory gene expression occurred in the neonatal MLN as early as 18 h postinfection. Marked innate phagocyte recruitment was subsequently detected at 24 h postinfection. Enzyme-linked immunosorbent spot assay (ELISPOT) analyses indicated that enhanced inflammation in neonatal MLN is contributed to, in part, by an increased frequency of proinflammatory cytokine-secreting cells. Moreover, both CD11b+ and CD11b− cell populations appeared to play a role in proinflammatory gene expression. The level of inflammation in neonatal MLN was also dependent on key bacterial components. Y. enterocolitica lacking the virulence plasmid failed to induce innate phagocyte recruitment. In contrast, tumor necrosis factor alpha (TNF-α) protein expression and neutrophil recruitment were strikingly higher in neonatal MLN after infection with a yopP-deficient strain than with wild-type Y. enterocolitica, whereas only modest increases occurred in adults. This hyperinflammatory response was associated with greater colonization of the spleen and higher mortality in neonates, while there was no difference in mortality among adults. This model highlights the dynamic levels of inflammation in the intestinal lymphoid tissues and reveals the protective (wild-type strain) versus harmful (yopP-deficient strain) consequences of inflammation in neonates. Moreover, these results reveal that the neonatal intestinal lymphoid tissues have great potential to rapidly mobilize innate components in response to infection with bacterial enteropathogens. PMID:24478090

Role of Host Type IA Phosphoinositide 3-Kinase Pathway Components in Invasin-Mediated Internalization of Yersinia enterocolitica.

PubMed

Dowd, Georgina C; Bhalla, Manmeet; Kean, Bernard; Thomas, Rowan; Ireton, Keith

2016-06-01

Many bacterial pathogens subvert mammalian type IA phosphoinositide 3-kinase (PI3K) in order to induce their internalization into host cells. How PI3K promotes internalization is not well understood. Also unclear is whether type IA PI3K affects different pathogens through similar or distinct mechanisms. Here, we performed an RNA interference (RNAi)-based screen to identify components of the type IA PI3K pathway involved in invasin-mediated entry of Yersinia enterocolitica, an enteropathogen that causes enteritis and lymphadenitis. The 69 genes targeted encode known upstream regulators or downstream effectors of PI3K. A similar RNAi screen was previously performed with the food-borne bacterium Listeria monocytogenes The results of the screen with Y. enterocolitica indicate that at least nine members of the PI3K pathway are needed for invasin-mediated entry. Several of these proteins, including centaurin-α1, Dock180, focal adhesion kinase (FAK), Grp1, LL5α, LL5β, and PLD2 (phospholipase D2), were recruited to sites of entry. In addition, centaurin-α1, FAK, PLD2, and mTOR were required for remodeling of the actin cytoskeleton during entry. Six of the human proteins affecting invasin-dependent internalization also promote InlB-mediated entry of L. monocytogenes Our results identify several host proteins that mediate invasin-induced effects on the actin cytoskeleton and indicate that a subset of PI3K pathway components promote internalization of both Y. enterocolitica and L. monocytogenes. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Rapid identification and typing of Yersinia pestis and other Yersinia species by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry

PubMed Central

2010-01-01

Background Accurate identification is necessary to discriminate harmless environmental Yersinia species from the food-borne pathogens Yersinia enterocolitica and Yersinia pseudotuberculosis and from the group A bioterrorism plague agent Yersinia pestis. In order to circumvent the limitations of current phenotypic and PCR-based identification methods, we aimed to assess the usefulness of matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) protein profiling for accurate and rapid identification of Yersinia species. As a first step, we built a database of 39 different Yersinia strains representing 12 different Yersinia species, including 13 Y. pestis isolates representative of the Antiqua, Medievalis and Orientalis biotypes. The organisms were deposited on the MALDI-TOF plate after appropriate ethanol-based inactivation, and a protein profile was obtained within 6 minutes for each of the Yersinia species. Results When compared with a 3,025-profile database, every Yersinia species yielded a unique protein profile and was unambiguously identified. In the second step of analysis, environmental and clinical isolates of Y. pestis (n = 2) and Y. enterocolitica (n = 11) were compared to the database and correctly identified. In particular, Y. pestis was unambiguously identified at the species level, and MALDI-TOF was able to successfully differentiate the three biotypes. Conclusion These data indicate that MALDI-TOF can be used as a rapid and accurate first-line method for the identification of Yersinia isolates. PMID:21073689

Rapid identification and typing of Yersinia pestis and other Yersinia species by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry.

PubMed

Ayyadurai, Saravanan; Flaudrops, Christophe; Raoult, Didier; Drancourt, Michel

2010-11-12

Accurate identification is necessary to discriminate harmless environmental Yersinia species from the food-borne pathogens Yersinia enterocolitica and Yersinia pseudotuberculosis and from the group A bioterrorism plague agent Yersinia pestis. In order to circumvent the limitations of current phenotypic and PCR-based identification methods, we aimed to assess the usefulness of matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) protein profiling for accurate and rapid identification of Yersinia species. As a first step, we built a database of 39 different Yersinia strains representing 12 different Yersinia species, including 13 Y. pestis isolates representative of the Antiqua, Medievalis and Orientalis biotypes. The organisms were deposited on the MALDI-TOF plate after appropriate ethanol-based inactivation, and a protein profile was obtained within 6 minutes for each of the Yersinia species. When compared with a 3,025-profile database, every Yersinia species yielded a unique protein profile and was unambiguously identified. In the second step of analysis, environmental and clinical isolates of Y. pestis (n = 2) and Y. enterocolitica (n = 11) were compared to the database and correctly identified. In particular, Y. pestis was unambiguously identified at the species level, and MALDI-TOF was able to successfully differentiate the three biotypes. These data indicate that MALDI-TOF can be used as a rapid and accurate first-line method for the identification of Yersinia isolates.

Sensitive in situ monitoring of a recombinant bioluminescent Yersinia enterocolitica reporter mutant in real time on Camembert cheese.

PubMed

Maoz, Ariel; Mayr, Ralf; Bresolin, Geraldine; Neuhaus, Klaus; Francis, Kevin P; Scherer, Siegfried

2002-11-01

Bioluminescent mutants of Yersinia enterocolitica were generated by transposon mutagenesis using a promoterless, complete lux operon (luxCDABE) derived from Photorhabdus luminescens, and their production of light in the cheese environment was monitored. Mutant B94, which had the lux cassette inserted into an open reading frame of unknown function was used for direct monitoring of Y. enterocolitica cells on cheeses stored at 10 degrees C by quantifying bioluminescence using a photon-counting, intensified charge-coupled device camera. The detection limit on cheese was 200 CFU/cm(2). Bioluminescence of the reporter mutant was significantly regulated by its environment (NaCl, temperature, and cheese), as well as by growth phase, via the promoter the lux operon had acquired upon transposition. At low temperatures, mutant B94 did not exhibit the often-reported decrease of photon emission in older cells. It was not necessary to include either antibiotics or aldehyde in the food matrix in order to gain quantitative, reproducible bioluminescence data. As far as we know, this is the first time a pathogen has been monitored in situ, in real time, in a "real-product" status, and at a low temperature.

Sensitive In Situ Monitoring of a Recombinant Bioluminescent Yersinia enterocolitica Reporter Mutant in Real Time on Camembert Cheese

PubMed Central

Maoz, Ariel; Mayr, Ralf; Bresolin, Geraldine; Neuhaus, Klaus; Francis, Kevin P.; Scherer, Siegfried

2002-01-01

Bioluminescent mutants of Yersinia enterocolitica were generated by transposon mutagenesis using a promoterless, complete lux operon (luxCDABE) derived from Photorhabdus luminescens, and their production of light in the cheese environment was monitored. Mutant B94, which had the lux cassette inserted into an open reading frame of unknown function was used for direct monitoring of Y. enterocolitica cells on cheeses stored at 10°C by quantifying bioluminescence using a photon-counting, intensified charge-coupled device camera. The detection limit on cheese was 200 CFU/cm2. Bioluminescence of the reporter mutant was significantly regulated by its environment (NaCl, temperature, and cheese), as well as by growth phase, via the promoter the lux operon had acquired upon transposition. At low temperatures, mutant B94 did not exhibit the often-reported decrease of photon emission in older cells. It was not necessary to include either antibiotics or aldehyde in the food matrix in order to gain quantitative, reproducible bioluminescence data. As far as we know, this is the first time a pathogen has been monitored in situ, in real time, in a “real-product” status, and at a low temperature. PMID:12406772

Psp Stress Response Proteins Form a Complex with Mislocalized Secretins in the Yersinia enterocolitica Cytoplasmic Membrane.

PubMed

Srivastava, Disha; Moumene, Amal; Flores-Kim, Josué; Darwin, Andrew J

2017-09-12

The bacterial phage shock protein system (Psp) is a conserved extracytoplasmic stress response that is essential for the virulence of some pathogens, including Yersinia enterocolitica It is induced by events that can compromise inner membrane (IM) integrity, including the mislocalization of outer membrane pore-forming proteins called secretins. In the absence of the Psp system, secretin mislocalization permeabilizes the IM and causes rapid cell death. The Psp proteins PspB and PspC form an integral IM complex with two independent roles. First, the PspBC complex is required to activate the Psp response in response to some inducing triggers, including a mislocalized secretin. Second, PspBC are sufficient to counteract mislocalized secretin toxicity. Remarkably, secretin mislocalization into the IM induces psp gene expression without significantly affecting the expression of any other genes. Furthermore, psp null strains are killed by mislocalized secretins, whereas no other null mutants have been found to share this specific secretin sensitivity. This suggests an exquisitely specific relationship between secretins and the Psp system, but there has been no mechanism described to explain this. In this study, we addressed this deficiency by using a coimmunoprecipitation approach to show that the Psp proteins form a specific complex with mislocalized secretins in the Y. enterocolitica IM. Importantly, analysis of different secretin mutant proteins also revealed that this interaction is absolutely dependent on a secretin adopting a multimeric state. Therefore, the Psp system has evolved with the ability to detect and detoxify dangerous secretin multimers while ignoring the presence of innocuous monomers. IMPORTANCE The phage shock protein (Psp) response has been linked to important phenotypes in diverse bacteria, including those related to antibiotic resistance, biofilm formation, and virulence. This has generated widespread interest in understanding various aspects of

The isolation of Yersinia sp. from feral and farmed deer faeces.

PubMed

Henderson, T G

1984-06-01

Faecal samples from clinically normal farmed red deer, wapiti, fallow deer; and feral red deer and white tail deer were examined for members of the genus Yersinia. From 922 samples 176 strains of Y.enterocolitica, 56 strains of Y.frederiksenii, 29 strains of Y.kristensenii, eight strains of Y.intermedia, and seven strains of Y.pseudotuberculosis were isolated. High isolation rates of Yersinia sp. were recorded from some farms. Two herds had isolation rates of 33.3% and 36.8%. Sixteen strains of Yersinia sp. in addition to strains of Y.psuedotuberculosis were found to be Hela cell invasive. The majority of these strains were confined to a single herd and represented Y.enterocolitica biotypes I, II and III, Y.intermedia, Y. fredericksenii, and Y.kristensenii.

Fate of Yersinia enterocolitica during manufacture, ripening and storage of Lighvan cheese.

PubMed

Hanifian, Shahram; Khani, Sajjad

2012-05-15

This study aimed to evaluate the behavior of virulent Yersinia enterocolitica (YE) during the manufacture, ripening and storage of Lighvan cheese with particular reference to strains of YE, initial inoculation level, and storage time. Three strains of YE with low (1 log cfu/ml) and high (3 log cfu/ml) inoculation levels were inoculated to raw whole ewe's milk which was then used for manufacturing of Lighvan cheese. Throughout the manufacturing, ripening and storage periods the number of YE was counted on selective media. Enumerated colonies were then confirmed by duplex PCR using ail and virF genes. Moreover, some microbial and physiochemical characteristics of the cheese samples were examined. According to the results, initial inoculation level and storage time had statistically significant (P<0.01) effects on persistency of YE, while strain type exhibited no statistically significant (P>0.01) impact on survival of the pathogen. Results showed a rapid increase in the number of YE during manufacturing, however, in the ripening and storage periods the number of YE was decreased and eventually it was eliminated in all cheese batches after 4 months of storage. Copyright © 2012 Elsevier B.V. All rights reserved.

Yersinia adhesin A (YadA)--beauty & beast.

PubMed

Mühlenkamp, Melanie; Oberhettinger, Philipp; Leo, Jack C; Linke, Dirk; Schütz, Monika S

2015-02-01

The trimeric autotransporter adhesin Yersinia adhesin A is the prototype of the type Vc secretion systems. It is expressed by enteropathogenic Yersinia enterocolitica and Yersinia pseudotuberculosis strains, but not by Yersinia pestis. A characteristic trait of YadA is its modular composition and trimeric nature. YadA consists of an N-terminal passenger domain which is exposed on the bacterial cell surface. The translocation of this passenger onto the surface is facilitated by a C-terminal β-barrel domain which concomitantly anchors YadA into the outer membrane with three YadA monomers contributing to the formation of a single β-barrel. In Y. enterocolitica, but not Y. pseudotuberculosis, YadA is a decisive virulence factor and its deletion renders the bacteria virtually avirulent in mouse models of infection. This striking importance of YadA in infection may derive from its manifold functions in host cell interaction. Presumably the most important function of YadA is that it mediates adhesion to extracellular matrix components of eukaryotic host cells. Only tight adhesion allows for the injection of "anti-host" effector proteins via a type III secretion system into the host cell cytosol. These effector proteins enable Yersinia to subvert the host immune system in order to replicate and establish infection. YadA is also essential for the survival of Y. enterocolitica upon contact with serum, an important immune-evasion mechanism called serum resistance. To this end, YadA interacts with several components of the host complement system, the first line of immune defense. This review will summarize recent findings about the structure and biogenesis of YadA and its interactions with the host complement system. Copyright © 2015 Elsevier GmbH. All rights reserved.

[Evaluation of the usefulness of selected virulence markers for the identification of virulent Yersinia enterocolitica strains. I. Phenotypic markders associated with Plasmid pYV].

PubMed

Gierczyński, R

2000-01-01

The species Yersinia enterocolitica includes either pathogenic or non-pathogenic strains. Therefore it is necessary to differentiate virulent bacilli from other. It is well known that pathogenic strains of Y. enterocolitica bearing virulence associated plasmid called pYV, which could be demonstrated by its isolation or detected by the presence of specific, phenotypic properties directly related with this plasmid. The aim of the presented paper was to check the ability of some phenotypic virulence markers associated with pYV, to detection of pathogenic Y. enterocolitica strains. In the presented work 152 (130 carrying pYV) clinical strains of Y. enterocolitica O3 isolated mainly from stool were examined for the presence of phenotypic virulence markers such as: calcium dependency, Congo-red binding, autoagglutination and agglutination with Mangifera indica extract. Both first features were detected parallel, on the same plate, using CRMOX (Congo-red, Magnesium Oxalate) agar. The detection of the tested markers in the examined strains was compared with the presence of virulence plasmid. The obtained results confirmed the observations done by other authors that Y. enterocolitica strains, in which bacilli bearing the virulence plasmid predominate, exhibit all tested phenotypic properties whereas the plasmid-cured isogenic strains show no one of these features. Therefore all the tested markers could be useful for detection of virulent Y. enterocolitica strains directly isolated from patients. The most useful virulence markers in bacteriological study seems to be calcium dependency and Congo-red binding, examined together by the use of CRMOX agar, because they confirm the presence of the virulence plasmid by parallel detection of two physiologically different features associated with this plasmid. In addition CRMOX agar allows for the examination rough strains while agglutination tests do not.

The effect of urea and ammonia treatments on the survival of Salmonella spp. and Yersinia enterocolitica in pig slurry.

PubMed

Bolton, D J; Ivory, C; McDowell, D A

2013-01-01

The objective of this study was to investigate the survival of Salmonella and Yersinia enterocolitica strains in pig slurry and evaluate urea and ammonia as disinfection strategies. Salmonella Anatum, Salmonella Derby, Salmonella Typhimurium DT19 and Y. enterocolitica bioserotypes 4, O:3, 2, O:5,27 and 1A, O:6,30 were selectively marked by insertion of the plasmid, pGLO encoding for green fluorescent protein and for ampicillin resistance. Strain cocktails were inoculated into fresh pig slurry (control), slurry treated with urea [final concentration 2% w/w, (0.33 mol l(-1) )] and slurry treated with ammonia [final concentration 0.5% w/w, (0.3 mol l(-1) )] and stored at 4, 14 and 25°C. Bacterial counts were determined at regular intervals on xylose lysine deoxycholate agar (XLD), and XLD supplemented with ampicillin (0.1 mg ml(-1) ) and arabinose (0.6 mg ml(-1) ) for Salmonella and cefsulodin-irgasan-novobiocin agar (CIN) and CIN supplemented with ampicillin and arabinose for Y. enterocolitica. The pH of the control-, urea- and ammonia-treated samples ranged from 7.1 to 7.7, 8.8 to 8.9 and 8.0 to 8.3, respectively. Salmonella D(4) values ranged from 2.71 to 21.29 days, D(14) values from 2.72 to 11.62 days and D(25) values from 1.76 to 6.85 days. The equivalent D values ranges for the Y. enterocolitica strains were 3.7-19.23, 1.8-16.67 and 1.63-7.09 days, respectively. Treatment significantly (P < 0.01) affected D values with control > ammonia > urea, as did incubation temperature; 4 > 14 > 25°C. Urea and to a lesser extent ammonia may be used to disinfect Salmonella- and/or Y. enterocolitica-contaminated pig slurry, decreasing the storage time required while increasing its fertilizer value. This study presents data supporting the treatment of pig slurry to kill important zoonotic agents, thereby reducing environmental contamination, cross-infection of other animals and decreasing zoonotic disease in the food chain. © 2012 The Society for Applied Microbiology.

Purification and characterization of Yersinia enterocolitica and Yersinia pestis LcrV–cholera toxin A2/B chimeras

PubMed Central

Davis, Chadwick T.; Arlian, Britni M.

2010-01-01

Yersinia pestis is a virulent human pathogen and potential biological weapon. Despite a long history of research on this organism, there is no licensed vaccine to protect against pneumonic forms of Y. pestis disease. In the present study, plasmids were constructed to express cholera toxin A2/B chimeric molecules containing the LcrV protective antigen from Y. enterocolitica and Y. pestis. These chimeras were expressed and purified to high yields from the supernatant of transformed E. coli. Western and GM1 ELISA assays were used to characterize the composition, receptor-binding and relative stability of the LcrV-CTA2/B chimera in comparison to cholera toxin. In addition, we investigated the ability of the Y. pestis LcrV-CTA2/B chimera to bind to and internalize into cultured epithelial cells and macrophages by confocal microscopy. These studies indicate that the uptake and trafficking of the LcrV antigen from the chimera is comparable to the trafficking of native toxin. Together these findings report that stable, receptor-binding, non-toxic LcrV-cholera toxin A2/B chimeras can be expressed at high levels in E. coli and purified from the supernatant. In addition, the internalization of antigen in vitro reported here supports the development of these molecules as novel mucosal vaccine candidates. PMID:20438844

Effectiveness of chlorine, organic acids and UV treatments in reducing Escherichia coli O157:H7 and Yersinia enterocolitica on apples.

PubMed

Escudero, M E; Velázquez, L; Favier, G; de Guzmán, A M

2003-06-01

This study assessed the effectiveness of 200 and 500 ppm of chlorine and organic acids (0.5% lactic acid and 0.5% citric acid) in wash solutions, and UV radiation for reducing Escherichia coli O157:H7 and Yersinia enterocolitica on apples contaminated by two different methods. Residual levels of these pathogens after different treatments were compared. On dip inoculated apples, Y. enterocolitica reductions of 2.66 and 2.77 logs were obtained with 200 and 500 ppm chlorine combined with 0.5% lactic acid, respectively. The E. coli O157:H7 population decreased 3.35 log with 0.5% lactic acid wash solution, and 2.72 and 2.62 logs after 500 ppm chlorine and 500 ppm chlorine plus 0.5% lactic acid treatments, respectively. Similar reductions were obtained with UV radiation. On spot inoculated apples, significant (p < 0.05) decreases of 4.67 and 4.58 logs were observed in E. coli O157:H7 and Y. enterocolitica levels, respectively, after 500 ppm chlorine plus 0.5% lactic acid treatment as compared with the control. In sectioned apples, microorganisms infiltrated in inner core region and pulp were not significantly (p < 0.05) affected by disinfection treatments. No pathogens were detected in the natural microflora on apples. Reductions such as those obtained with 500 ppm chlorine plus 0.5% lactic acid solution were very proximal to the 5-log score required by FDA for apple disinfection.

Simultaneous Detection of Yersinia Enterocolitica and Listeria Monocytogenes in Foodstuffs by Capillary Electrophoresis and Microchip Capillary Electrophoresis Laser-Induced Fluorescence Detector.

PubMed

Li, Yongru; Su, Hongwei; Lan, Yajia

2018-05-29

Background: Food safety is one of the most important public health problems in the world,and pathogenic bacterium is a major factor causing serious foodborne diseases. Objective: Two methods of duplex PCR combined with capillary electrophoresis laser-induced fluorescence detector (CE-LIF) and microchip capillary electrophoresis laser-induced fluorescence detector (MCE-LIF) have been developed for the simultaneous detection of Yersinia enterocolitica and Listeria monocytogenes in various foods. The specific conservative sequences of these two bacteria were amplified. Methods: After labelled with nucleic acid dye SYBR Gold and SYBR Orange, the PCR products were analyzed by CE-LIF and MCE-LIF, respectively. Under the optimal conditions, the detection of PCR products of the target bacteria was achieved in less than 15 min by CE-LIF and within 6 min by MCE-LIF. Results: The alignment analysis demonstrated that the PCR products had good agreement with the sequences published in GenBank. The CE-LIF method could detect 10 CFU/mL Y. enterocolitica and L. monocytogenes , and the MCE-LIF method could detect 100 CFU/mL Y. enterocolitica and L. monocytogenes . The intraday precisions of migration time and peak area of DNA markers and PCR products were in the range of 1.13 to 1.18% and 1.60 to 6.29%, respectively, for CE-LIF and 1.18 to 1.48% and 2.85 to 4.06%, respectively, for MCE-LIF. Conclusions : The proposed methods could be applied to target bacterial detection infood samples rapidly, sensitively, and specifically. Highlights : Two new methods based on CE and MCE have been developed for the simultaneous detection of Y. enterocolitica and L. monocytogenes in foodstuffs, and they can detect the bacteria directly without any enrichment because of their high sensitivity.

Effects of lactic acid and commercial chilling processes on survival of Salmonella, Yersinia enterocolitica, and Campylobacter coli in pork variety meats.

PubMed

King, Amanda M; Miller, Rhonda K; Castillo, Alejandro; Griffin, Davey B; Hardin, Margaret D

2012-09-01

Current industry chilling practices with and without the application of 2% L-lactic acid were compared for their effectiveness at reducing levels of Salmonella, Yersinia enterocolitica, and Campylobacter coli on pork variety meats. Pork variety meats (livers, intestines, hearts, and stomachs) were inoculated individually with one of the three pathogens and subjected to five different treatment combinations that included one or more of the following: water wash (25°C), lactic acid spray (2%, 40 to 50°C), chilling (4°C), and freezing (-15°C). Samples were analyzed before treatment, after each treatment step, and after 2, 4, and 6 months of frozen storage. Results showed that when a lactic acid spray was used in combination with water spray, immediate reductions were approximately 0.5 log CFU per sample of Salmonella, 0.8 log CFU per sample of Y. enterocolitica, and 1.1 log CFU per sample of C. coli. Chilling, both alone and in combination with spray treatments, had little effect on pathogens, while freezing resulted in additional 0.5-log CFU per sample reductions in levels of Salmonella and Y. enterocolitica, and an additional 1.0-log CFU per sample reduction in levels of C. coli. While reductions of at least 1 log CFU per sample were observed on variety meats treated with only a water wash and subsequently frozen, samples treated with lactic acid had greater additional reductions than those treated with only a water spray throughout frozen storage. The results of this study suggest that the use of lactic acid as a decontamination intervention, when used in combination with good manufacturing practices during processing, causes significant reductions in levels of Salmonella, Y. enterocolitica, and C. coli on pork variety meats.

Radiation resistance and loss of crystal violet binding activity in Yersinia enterocolitica suspended in raw ground pork exposed to gamma radiation and modified atmosphere.

PubMed

Bhaduri, Saumya; Sheen, Shiowshuh; Sommers, Christopher H

2014-05-01

Virulence of many foodborne pathogens is directly linked to genes carried on self-replicating extra-chromosomal elements, which can transfer genetic material, both vertically and horizontally, between bacteria of the same and different species. Pathogenic Yersinia enterocolitica harbors a 70-kb virulence plasmid (pYV) that encodes genes for low calcium response, crystal violet (CV) binding, Congo red uptake, autoagglutination (AA), hydrophobicity (HP), type III secretion channels, host immune suppression factors, and biofilm formation. Ionizing radiation and modified atmosphere packaging (MAP) are used to control foodborne pathogens and meat spoilage. In this study, the effect of gamma radiation and modified atmosphere (air, 100% N2 , 75% N2 : 25% CO2 , 50% N2 : 50% CO2 , 25% N2 : 75% CO2 , 100% CO2 ) were examined by using the CV binding phenotype, for the presence or absence of pYV in Y. enterocolitica, suspended in raw ground pork. All Y. enterocolitica serovars used (O:3, O:8, and O5,27) were more sensitive to radiation as the CO2 concentration increased above 50%. Crystal violet binding following a radiation dose of 1.0 kGy, which reduced the Y. enterocolitica serovars >5 log, was greatest in the presence of air (ca. 8%), but was not affected by N2 or CO2 concentration (ca. 5%). Following release from modified atmosphere after irradiation, the loss of CV binding rose from 5% to 8% immediately following irradiation to >30% after outgrowth at 25 °C for 24 h. These results, using Y. enterocolitica as a model system, indicate that the risk of foodborne illness could be affected by the loss of virulence factors when postprocess intervention technologies are used. Provides gamma radiation D10 data for inactivation data for Y. enterocolitica irradiated under modified atmosphere and information to risk assessors regarding the difference between pathogen presence versus actual virulence. Published 2014. This article is a U.S. Government work and is in the public

[Detection of Salmonella, Listeria spp., Vibrio spp., and Yersinia enterocolitica in frozen seafood and comparison with enumeration for faecal indicators: implication for public health].

PubMed

Ripabelli, G; Sammarco, M L; Fanelli, I; Grasso, G M

2004-01-01

Infections transmitted through consumption of contaminated seafood is a significant source of human morbidity. The aim of this study was to compare the detection of Salmonella, Listeria, Vibrio, and Yersinia enterocolitica in frozen seafood with results from enumeration of conventional faecal indicators. A total of 213 crustaceans or molluscs were purchased from local vendors in Italy: 74% were harvested in Italy, 25% from other European countries and 1% from outside Europe. Listeria spp. was isolated from 20% of samples, Vibrio spp. from 11%, Salmonella from 3% and Y. enterocolitica from 1%. Listeria species isolated were L. monocytogenes, L. innocua, L. welshimeri, L. ivanovii and L. seeligeri. Vibrio species isolated were V. alginolyticus and V. fluvialis. The most contaminated shellfish for both faecal indicator microrganism and pathogens were hen clams (6% contained Salmonella, 27% Listeria spp. and 3% Y. enterocolitica), while from 27% of shrimps Vibrio spp. was recovered. Higher levels of faecal indicators were recovered from samples harvested outside Europe, and 66% of samples harvested in Thailand were contaminated from Salmonella. Significant differences were found in the levels of contamination of seafoods depending upon the freezing regime, but there was a limited association between presence of potential pathogens (particularly Vibrio spp.) and conventional faecal indicators. Hence, we suggest reconsideration of current legal parameters to evaluate microbiological quality of seafood.

A case-control study of Yersinia enterocolitica infections in Auckland.

PubMed

Satterthwaite, P; Pritchard, K; Floyd, D; Law, B

1999-10-01

To identify major risk factors for Yersinia enterocolitica (YE) and identify measures to reduce YE infections. A prospective case control study, group age matched, using 186 cases of YE identified by community pathology laboratories and 379 randomly selected controls. Conducted between April 1995 and June 1996 in Auckland, New Zealand. Face-to-face interviews used a standardised questionnaire examining exposures to factors potentially associated with YE infections including untreated water, unreticulated sewerage, consumption of selected foods, selected food handling practices and socio-demographic factors. Multivariate logistic regression was used to calculate adjusted odds ratios for the potential risk factors. Population attributable risk (PAR) was calculated for significant exposures. Having more than two people living in the home was more common among cases than controls (OR = 2.2). Town supply water (OR = 0.2), reticulated sewerage (OR = 0.34) and looking after a young child (OR = 0.51) were significantly less common. Of the meats, only pork (OR = 1.34) had a higher consumption rate, while bacon (OR = 0.75) and smallgoods (OR = 0.73) were consumed less frequently by cases than controls. Eating food from a sandwich bar was more frequent among cases (OR = 1.18). Fruit and vegetable consumption was marginally less (OR = 0.98). The population attributable risk of these factors was 0.89, implying that 89% of YE would be eliminated if adverse exposures were removed. The risk of YE illness is increased by contact with untreated water, unreticulated sewerage and consumption of pork. Investigation of non-town water supply, informal sewerage systems and methods of preparation and consumption of pork are recommended to determine how YE enters the human food chain.

Yersinia enterocolitica YopT and Clostridium difficile Toxin B Induce Expression of GILZ in Epithelial Cells

PubMed Central

Köberle, Martin; Göppel, David; Grandl, Tanja; Gaentzsch, Peer; Manncke, Birgit; Berchtold, Susanne; Müller, Steffen; Lüscher, Bernhard; Asselin-Labat, Marie-Liesse; Pallardy, Marc; Sorg, Isabel; Langer, Simon; Barth, Holger; Zumbihl, Robert; Autenrieth, Ingo B.; Bohn, Erwin

2012-01-01

Glucocorticoid induced-leucine zipper (GILZ) has been shown to be induced in cells by different stimuli such as glucocorticoids, IL-10 or deprivation of IL-2. GILZ has anti-inflammatory properties and may be involved in signalling modulating apoptosis. Herein we demonstrate that wildtype Yersinia enterocolitica which carry the pYV plasmid upregulated GILZ mRNA levels and protein expression in epithelial cells. Infection of HeLa cells with different Yersinia mutant strains revealed that the protease activity of YopT, which cleaves the membrane-bound form of Rho GTPases was sufficient to induce GILZ expression. Similarly, Clostridium difficile toxin B, another bacterial inhibitor of Rho GTPases induced GILZ expression. YopT and toxin B both increased transcriptional activity of the GILZ promoter in HeLa cells. GILZ expression could not be linked to the inactivation of an individual Rho GTPase by these toxins. However, forced expression of RhoA and RhoB decreased basal GILZ promoter activity. Furthermore, MAPK activation proved necessary for profound GILZ induction by toxin B. Promoter studies and gel shift analyses defined binding of upstream stimulatory factor (USF) 1 and 2 to a canonical c-Myc binding site (E-box) in the GILZ promoter as a crucial step of its trans-activation. In addition we could show that USF-1 and USF-2 are essential for basal as well as toxin B induced GILZ expression. These findings define a novel way of GILZ promoter trans-activation mediated by bacterial toxins and differentiate it from those mediated by dexamethasone or deprivation of IL-2. PMID:22792400

A miniaturised semiautomated system for the identification of Yersinia species within the genus Yersinia.

PubMed

Neubauer, H; Molitor, M; Rahalison, L; Aleksic, S; Backes, H; Chanteau, S; Meyer, H

2000-01-01

Commercially available identification systems based on biochemical reactions of bacteria are not suited for typing the species of the genus Yersinia (Y.) or the biovars (BV) of the species Y. enterocolitica. This failure is caused by the limited number of biochemical reactions applied, resulting in the absence of important discriminatory key reactions. The MICRONAUT identification system (Merlin, Bornheim-Hersel) makes use of dried substrates/enzymes reactions in the wells of a 96-well microtitration plate, reading of the results by a scanner device and typing of the isolate by the calculation of probabilities according to a data base. For this study a special identification panel was designed on which 38 substrates and enzyme reactions were configurated including 20 reactions for the identification of the species of the genus and the Y. enterocolitica biovars. The database was calculated using the results obtained from a total of 250 Yersinia strains of the eleven species of the genus. Reevaluation of the results of these strains revealed an overall sensitivity of 98%, as only four strains were not identified satisfactorily. Considering also questionable results the sensitivity was still 85%. The system was also used to identify Y. pestis isolates, but in this case reading was done visually. The printouts usually cite species designation, identification quality and probabilities. The sealing of the plates in an aluminium bag guarantees long life and long lasting quality. However, an evaluation of the system with a considerable number of strains has to be done in a next step. The 'Yersinia identification set' can replace time-consuming tube testing in the future and is a big step forward towards a sensitive identification of Yersinia isolates in the routine laboratory.

Molecular modeling and simulation studies of recombinant laccase from Yersinia enterocolitica suggests significant role in the biotransformation of non-steroidal anti-inflammatory drugs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Singh, Deepti; Rawat, Surender; Waseem, Mohd

The YacK gene from Yersinia enterocolitica strain 7, cloned in pET28a vector and expressed in Escherichia coli BL21 (DE3), showed laccase activity when oxidized with 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) and guaiacol. The recombinant laccase protein was purified and characterized biochemically with a molecular mass of ≈58 KDa on SDS-PAGE and showed positive zymogram with ABTS. The protein was highly robust with optimum pH 9.0 and stable at 70 °C upto 12 h with residual activity of 70%. Kinetic constants, K{sub m} values, for ABTS and guaiacol were 675 μM and 2070 μM, respectively, with corresponding Vmax values of 0.125 μmol/ml/min and 6500 μmol/ml/min. It also possess antioxidative propertymore » against BSA and Cu{sup 2+}/H{sub 2}O{sub 2} model system. Constant pH MD simulation studies at different protonation states of the system showed ABTS to be most stable at acidic pH, whereas, diclofenac at neutral pH. Interestingly, aspirin drifted out of the binding pocket at acidic and neutral pH, but showed stable binding at alkaline pH. The biotransformation of diclofenac and aspirin by laccase also corroborated the in silico results. This is the first report on biotransformation of non-steroidal anti-inflammatory drugs (NSAIDs) using recombinant laccase from gut bacteria, supported by in silico simulation studies. - Highlights: • Laccase from Yersinia enterocolitica strain 7 was expressed in Escherichia coli BL21 (DE3). • Recombinant laccase was found to be thermostable and alkali tolerant. • The in silico and experimental studied proves the biotransformation of NSAIDs. • Laccase binds to ligands differentially under different protonation state. • Laccase also possesses free radical scavenging property.« less

A transcriptomic analysis of Yersinia enterocolitica biovar 1B infecting murine macrophages reveals new mechanisms of intracellular survival

DOE PAGES

Bent, Zachary W.; Poorey, Kunal; Brazel, David M.; ...

2015-04-20

Yersinia enterocolitica is typically considered an extracellular pathogen; however, during the course of an infection, a significant number of bacteria are stably maintained within host cell vacuoles. Little is known about this population and the role it plays during an infection. To address this question and to elucidate the spatially and temporally dynamic gene expression patterns of Y. enterocoliticabiovar 1B through the course of an in vitro infection, transcriptome sequencing and differential gene expression analysis of bacteria infecting murine macrophage cells were performed under four distinct conditions. Bacteria were first grown in a nutrient-rich medium at 26°C to establish amore » baseline of gene expression that is unrelated to infection. The transcriptomes of these bacteria were then compared to bacteria grown in a conditioned cell culture medium at 37°C to identify genes that were differentially expressed in response to the increased temperature and medium but not in response to host cells. Infections were then performed, and the transcriptomes of bacteria found on the extracellular surface and intracellular compartments were analyzed individually. The upregulated genes revealed potential roles for a variety of systems in promoting intracellular virulence, including the Ysa type III secretion system, the Yts2 type II secretion system, and the Tad pilus. It was further determined that mutants of each of these systems had decreased virulence while infecting macrophages. Overall, these results reveal the complete set of genes expressed by Y. enterocolitica in response to infection and provide the groundwork for future virulence studies.« less

Complete Genome Sequence of a Yersinia enterocolitica “Old World” (3/O:9) Strain and Comparison with the “New World” (1B/O:8) Strain▿†

PubMed Central

Wang, Xin; Li, Yang; Jing, Huaiqi; Ren, Yan; Zhou, Zhemin; Wang, Shaojing; Kan, Biao; Xu, Jianguo; Wang, Lei

2011-01-01

Yersinia enterocolitica is a heterogeneous bacterial species with a wide range of animal reservoirs through which human intestinal illness can be facilitated. In contrast to the epidemiological pattern observed in the United States, infections in China present a pattern similar to those in European countries and Japan, wherein “Old World” strains (biotypes 2 to 5) are prevalent. To gain insights into the evolution of Y. enterocolitica and pathogenic properties toward human hosts, we sequenced the genome of a biotype 3 strain, 105.5R(r) (O:9), obtained from a Chinese patient. Comparative genome sequence analysis with strain 8081 (1B/O:8) revealed new insights into Y. enterocolitica. Both strains have more than 14% specific genes. In strain 105.5R(r), putative virulence factors were found in strain-specific genomic pathogenicity islands that comprised a novel type III secretion system and rtx-like genes. Many of the loci representing ancestral clusters, which are believed to contribute to enteric survival and pathogenesis, are present in strain 105.5R(r) but lost in strain 8081. Insertion elements in 105.5R(r) have a pattern distinct from those in strain 8081 and were exclusively located in a strain-specific region. In summary, our comparative genome analysis indicates that these two strains may have attained their pathogenicity by completely separate evolutionary events, and the 105.5R(r) strain, a representative of the Old World biogroup, lies in a branch of Y. enterocolitica that is distinct from the “New World” 8081 strain. PMID:21325549

Acting on Actin: Rac and Rho Played by Yersinia.

PubMed

Aepfelbacher, Martin; Wolters, Manuel

2017-01-01

Pathogenic bacteria of the genus Yersinia include Y. pestis-the agent of plaque-and two enteropathogens, Y. enterocolitica, and Y. pseudotuberculosis. These pathogens have developed an array of virulence factors aimed at manipulating Rho GTP-binding proteins and the actin cytoskeleton in host cells to cross the intestinal barrier and suppress the immune system. Yersinia virulence factors include outer membrane proteins triggering cell invasion by binding to integrins, effector proteins injected into host cells to manipulate Rho protein functions and a Rho protein-activating exotoxin. Here, we present an overview of how Yersinia and host factors are integrated in a regulatory network that orchestrates the subversion of host defense.

Epidemiologic investigation of a Yersinia camp outbreak linked to a food handler.

PubMed

Morse, D L; Shayegani, M; Gallo, R J

1984-06-01

In July 1981, an outbreak of gastroenteritis occurred at a summer diet camp. Of the 455 campers and staff, 35 per cent developed an illness characterized by abdominal pain, fever, diarrhea, and/or nausea and vomiting. A total of 53 per cent experienced abdominal pain. Seven persons were hospitalized, five of whom had appendectomies. Yersinia enterocolitica serogroup 0:8 was isolated from 37 (54 per cent) of 69 persons examined, including the camp cook and three assistants. An epidemiologic investigation demonstrated that illness was associated with consumption of reconstituted powdered milk and/or chow mein . Y. enterocolitica serogroup 0:8 was subsequently isolated from milk, the milk dispenser, and leftover chow mein . Information obtained during the investigation suggested that the Yersinia had been introduced by a food handler during food-processing procedures.

Usefulness of in-house obtained recombinant proteins Yop of Yersinia enterocolitica as highly specific antigens in ELISA and recom-dot performed in the serodiagnosis of yersiniosis.

PubMed

Rastawicki, Waldemar; Smietafiska, Karolina; Chrost, Anna; Wolkowicz, Tomasz; Rokosz-Chudziak, Natalia

Proper analysis of the human immune response is crucial in the laboratory diagnosis of many bacterial infections-The current serological diagnosis of yersiniosis often is carried out using ELISA with native antigens. However, recombinant proteins increase the specificity of the serological assays, particularly in patients with chronic, non- specific infections. The aim of the present study was to evaluate the usefulness of in-house obtained recombinant proteins Yop of Yersinia enterocolitica as highly specific antigens in ELISA and recom-dot performed in the serodiagnosis of yersiniosis. Recombinant YopD, YopB, YopE and V-Ag proteins of Y enterocolitica were expressing in E. coli BL21 (DE3) using the pET-30 Ek/LIC expression vector (Novagen). Purification was accomplished by immobilized metal (Ni2) affinity column chromatography (His-trap). The proteins were used as antigens in standard ELISA and recom-dot assay, which was performed on nitrocellulose strips. The study population, used for characterization of the humoral immune response to the recombinant proteins, consisted of 74 patients suspected for Y enterocolitica infection and 41 clinically healthy blood donors. Some of the results obtained by ELISA and recom-dot were compared with results obtained by commercial western-blot Yersinia (Virotech). In the group of patients suspected for yersiniosis in clinical investigation the most positive results were obtained in ELISA with the recombinant protein YopD (IgA respectively 25 (42.4%), IgG 41 (69.5%), IgM 24 (40.7%). The percentage ofpositive results in the group of blood donors did not exceed 10.0% in IgG and 5.0% in IgA/IgM classes of immunoglobulin. The results obtained in the recom-dot assay showed that among 74 tested serum samples obtained from individuals suspected of yersiniosis the most common IgA, IgG and IgM antibodies were found for recombinant protein YopD (respectively IgG in 60.8%, IgA in 37.8% and IgM in 33.8% of serum samples). IgG antibodies to

Immunization with a DNA adenine methylase over-producing Yersinia pseudotuberculosis vaccine confers robust cross-protection against heterologous pathogenic serotypes.

PubMed

Kubicek-Sutherland, Jessica Z; Heithoff, Douglas M; Ersoy, Selvi C; Shimp, William R; Mahan, Michael J

2014-03-14

Yersinia pseudotuberculosis is a foodborne pathogen that can cause serious human illness. Although the source and route of transmission often remain obscure, livestock have been implicated in some cases. The diversity of yersiniae present on farms and their widespread distribution in animal and environmental reservoirs necessitates the use of broad prophylactic strategies that are efficacious against many serotypes simultaneously. Herein, immunization of mice with a modified, live attenuated Y. pseudotuberculosis vaccine that overproduces the DNA adenine methylase (Dam(OP)) conferred robust protection against virulent challenge (150-fold LD50) with homologous and heterologous serotypes that have been associated with human disease (O:1, O:1a, O:3). Further, the dam gene was shown to be essential for cell viability in all (7 of 7) Y. pseudotuberculosis strains tested. Direct selection for the inheritance of dam mutant alleles in Y. pseudotuberculosis resulted in dam strain variants that contained compensatory (second-site suppressor) mutations in genes encoding methyl-directed mismatch repair proteins (mutHLS) that are involved in suppression of the non-viable cell phenotype in all (19/19) strains tested. Such dam mutH variants exhibited a significant increase in virulence and spontaneous mutation frequency relative to that of a Dam(OP) vaccine strain. These studies indicate that Y. pseudotuberculosis Dam(OP) strains conferred potent cross-protective efficacy as well as decreased virulence and spontaneous mutation frequency relative to those that lack Dam, which have compensatory mutations in mutHLS loci. These data suggest that development of yersiniae livestock vaccines based on Dam overproduction is a viable mitigation strategy to reduce these potential foodborne contaminants. Copyright © 2014 Elsevier Ltd. All rights reserved.

'Add, stir and reduce': Yersinia spp. as model bacteria for pathogen evolution.

PubMed

McNally, Alan; Thomson, Nicholas R; Reuter, Sandra; Wren, Brendan W

2016-03-01

Pathogenic species in the Yersinia genus have historically been targets for research aimed at understanding how bacteria evolve into mammalian pathogens. The advent of large-scale population genomic studies has greatly accelerated the progress in this field, and Yersinia pestis, Yersinia pseudotuberculosis and Yersinia enterocolitica have once again acted as model organisms to help shape our understanding of the evolutionary processes involved in pathogenesis. In this Review, we highlight the gene gain, gene loss and genome rearrangement events that have been identified by genomic studies in pathogenic Yersinia species, and we discuss how these findings are changing our understanding of pathogen evolution. Finally, as these traits are also found in the genomes of other species in the Enterobacteriaceae, we suggest that they provide a blueprint for the evolution of enteropathogenic bacteria.

Yersinia adhesins: An arsenal for infection.

PubMed

Chauhan, Nandini; Wrobel, Agnieszka; Skurnik, Mikael; Leo, Jack C

2016-10-01

The Yersiniae are a group of Gram-negative coccobacilli inhabiting a wide range of habitats. The genus harbors three recognized human pathogens: Y. enterocolitica and Y. pseudotuberculosis, which both cause gastrointestinal disease, and Y. pestis, the causative agent of plague. These three organisms have served as models for a number of aspects of infection biology, including adhesion, immune evasion, evolution of pathogenic traits, and retracing the course of ancient pandemics. The virulence of the pathogenic Yersiniae is heavily dependent on a number of adhesin molecules. Some of these, such as the Yersinia adhesin A and invasin of the enteropathogenic species, and the pH 6 antigen of Y. pestis, have been extensively studied. However, genomic sequencing has uncovered a host of other adhesins present in these organisms, the functions of which are only starting to be investigated. Here, we review the current state of knowledge on the adhesin molecules present in the Yersiniae, and their functions and putative roles in the infection process. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Yersinia pestis Ail: multiple roles of a single protein

PubMed Central

Kolodziejek, Anna M.; Hovde, Carolyn J.; Minnich, Scott A.

2012-01-01

Yersinia pestis is one of the most virulent bacteria identified. It is the causative agent of plague—a systemic disease that has claimed millions of human lives throughout history. Y. pestis survival in insect and mammalian host species requires fine-tuning to sense and respond to varying environmental cues. Multiple Y. pestis attributes participate in this process and contribute to its pathogenicity and highly efficient transmission between hosts. These include factors inherited from its enteric predecessors; Y. enterocolitica and Y. pseudotuberculosis, as well as phenotypes acquired or lost during Y. pestis speciation. Representatives of a large Enterobacteriaceae Ail/OmpX/PagC/Lom family of outer membrane proteins (OMPs) are found in the genomes of all pathogenic Yersiniae. This review describes the current knowledge regarding the role of Ail in Y. pestis pathogenesis and virulence. The pronounced role of Ail in the following areas are discussed (1) inhibition of the bactericidal properties of complement, (2) attachment and Yersinia outer proteins (Yop) delivery to host tissue, (3) prevention of PMNL recruitment to the lymph nodes, and (4) inhibition of the inflammatory response. Finally, Ail homologs in Y. enterocolitica and Y. pseudotuberculosis are compared to illustrate differences that may have contributed to the drastic bacterial lifestyle change that shifted Y. pestis from an enteric to a vector-born systemic pathogen. PMID:22919692

Contribution of trimeric autotransporter C-terminal domains of oligomeric coiled-coil adhesin (Oca) family members YadA, UspA1, EibA, and Hia to translocation of the YadA passenger domain and virulence of Yersinia enterocolitica.

PubMed

Ackermann, Nikolaus; Tiller, Maximilian; Anding, Gisela; Roggenkamp, Andreas; Heesemann, Jürgen

2008-07-01

The Oca family is a novel class of autotransporter-adhesins with highest structural similarity in their C-terminal transmembrane region, which supposedly builds a beta-barrel pore in the outer membrane (OM). The prototype of the Oca family is YadA, an adhesin of Yersinia enterocolitica and Yersinia pseudotuberculosis. YadA forms a homotrimeric lollipop-like structure on the bacterial surface. The C-terminal regions of three YadA monomers form a barrel in the OM and translocate the trimeric N-terminal passenger domain, consisting of stalk, neck, and head region to the exterior. To elucidate the structural and functional role of the C-terminal translocator domain (TLD) and to assess its promiscuous capability with respect to transport of related passenger domains, we constructed chimeric YadA proteins, which consist of the N-terminal YadA passenger domain and C-terminal TLDs of Oca family members UspA1 (Moraxella catarrhalis), EibA (Escherichia coli), and Hia (Haemophilus influenzae). These constructs were expressed in Y. enterocolitica and compared for OM localization, surface exposure, oligomerization, adhesion properties, serum resistance, and mouse virulence. We demonstrate that all chimeric YadA proteins translocated the YadA passenger domain across the OM. Y. enterocolitica strains producing YadA chimeras or wild-type YadA showed comparable binding to collagen and epithelial cells. However, strains producing YadA chimeras were attenuated in serum resistance and mouse virulence. These results demonstrate for the first time that TLDs of Oca proteins of different origin are efficient translocators of the YadA passenger domain and that the cognate TLD of YadA is essential for bacterial survival in human serum and mouse virulence.

Virulence-related genes, adhesion and invasion of some Yersinia enterocolitica-like strains suggests its pathogenic potential.

PubMed

Imori, Priscilla F M; Passaglia, Jaqueline; Souza, Roberto A; Rocha, Lenaldo B; Falcão, Juliana P

2017-03-01

Yersina enterocolitica-like species have not been extensively studied regarding its pathogenic potential. This work aimed to assess the pathogenic potential of some Y. enterocolitica-like strains by evaluating the presence of virulence-related genes by PCR and their ability to adhere to and invade Caco-2 and HEp-2 cells. A total of 50 Y. frederiksenii, 55 Y. intermedia and 13 Y. kristensenii strains were studied. The strains contained the following genes: Y. frederiksenii, fepA(44%), fes(44%) and ystB(18%); Y. intermedia, ail(53%), fepA (35%), fepD(2%), fes(97%), hreP(2%), ystB(2%) and tccC(35%); Y. kristensenii, ail(62%), ystB(23%), fepA(77%), fepD(54%), fes(54%) and hreP(77%). Generally, the Y. enterocolitica-like strains had a reduced ability to adhere to and invade mammalian cells compared to the highly pathogenic Y. enterocolitica 8081. However, Y. kristensenii FCF410 and Y. frederiksenii FCF461 presented high invasion potentials in Caco-2 cells after five days of pre-incubation increased by 45- and 7.2-fold compared to Y. enterocolitica 8081, respectively; but, the ail gene was not detected in these strains. The presence of virulence-related genes in some of the Y. enterocolitica-like strains indicated their possible pathogenic potential. Moreover, the results suggest the existence of alternative virulence mechanisms and that the pathogenicity of Y. kristensenii and Y. frederiksenii may be strain-dependent. Copyright © 2017 Elsevier Ltd. All rights reserved.

Predicting the kinetics of Listeria monocytogenes and Yersinia enterocolitica under dynamic growth/death-inducing conditions, in Italian style fresh sausage.

PubMed

Iannetti, Luigi; Salini, Romolo; Sperandii, Anna Franca; Santarelli, Gino Angelo; Neri, Diana; Di Marzio, Violeta; Romantini, Romina; Migliorati, Giacomo; Baranyi, József

2017-01-02

Traditional Italian pork products can be consumed after variable drying periods, where the temporal decrease of water activity spans from optimal to inactivating values. This makes it necessary to A) consider the bias factor when applying culture-medium-based predictive models to sausage; B) apply the dynamic version (described by differential equations) of those models; C) combine growth and death models in a continuous way, including the highly uncertain growth/no growth range separating the two regions. This paper tests the applicability of published predictive models on the responses of Listeria monocytogenes and Yersinia enterocolitica to dynamic conditions in traditional Italian pork sausage, where the environment changes from growth-supporting to inhibitory conditions, so the growth and death models need to be combined. The effect of indigenous lactic acid bacteria was also taken into account in the predictions. Challenge tests were carried out using such sausages, inoculated separately with L. monocytogenes and Y. enterocolitica, stored for 480h at 8, 12, 18 and 20°C. The pH was fairly constant, while the water activity changed dynamically. The effects of the environment on the specific growth and death rate of the studied organisms were predicted using previously published predictive models and parameters. Microbial kinetics in many products with a long shelf-life and dynamic internal environment, could result in both growth and inactivation, making it difficult to estimate the bacterial concentration at the time of consumption by means of commonly available predictive software tools. Our prediction of the effect of the storage environment, where the water activity gradually decreases during a drying period, is designed to overcome these difficulties. The methodology can be used generally to predict and visualise bacterial kinetics under temporal variation of environments, which is vital when assessing the safety of many similar products. Copyright �

The Virulence Plasmid of Yersinia, an Antihost Genome

PubMed Central

Cornelis, Guy R.; Boland, Anne; Boyd, Aoife P.; Geuijen, Cecile; Iriarte, Maite; Neyt, Cécile; Sory, Marie-Paule; Stainier, Isabelle

1998-01-01

The 70-kb virulence plasmid enables Yersinia spp. (Yersinia pestis, Y. pseudotuberculosis, and Y. enterocolitica) to survive and multiply in the lymphoid tissues of their host. It encodes the Yop virulon, an integrated system allowing extracellular bacteria to disarm the cells involved in the immune response, to disrupt their communications, or even to induce their apoptosis by the injection of bacterial effector proteins. This system consists of the Yop proteins and their dedicated type III secretion apparatus, called Ysc. The Ysc apparatus is composed of some 25 proteins including a secretin. Most of the Yops fall into two groups. Some of them are the intracellular effectors (YopE, YopH, YpkA/YopO, YopP/YopJ, YopM, and YopT), while the others (YopB, YopD, and LcrV) form the translocation apparatus that is deployed at the bacterial surface to deliver the effectors into the eukaryotic cells, across their plasma membrane. Yop secretion is triggered by contact with eukaryotic cells and controlled by proteins of the virulon including YopN, TyeA, and LcrG, which are thought to form a plug complex closing the bacterial secretion channel. The proper operation of the system also requires small individual chaperones, called the Syc proteins, in the bacterial cytosol. Transcription of the genes is controlled both by temperature and by the activity of the secretion apparatus. The virulence plasmid of Y. enterocolitica and Y. pseudotuberculosis also encodes the adhesin YadA. The virulence plasmid contains some evolutionary remnants including, in Y. enterocolitica, an operon encoding resistance to arsenic compounds. PMID:9841674

Survival of Escherichia coli O157:H7, Listeria monocytogenes 4b and Yersinia enterocolitica O3 in different yogurt and kefir combinations as prefermentation contaminant.

PubMed

Gulmez, M; Guven, A

2003-01-01

To compare microbiological safety of yogurt, kefir and different combinations of yogurt and kefir samples by using three foodborne pathogenic strains (Escherichia coli O157:H7, Listeria monocytogenes 4b and Yersinia enterocolitica O3) as indicators. Fresh yogurt and kefir drinks were added to pasteurized milk at a 5% rate either separately or together, and then incubated at different temperatures (43 degrees C for yogurt and 30 degrees C for kefir), depending on appropriate growth temperature of their starter microflora. While traditional yogurt was found to be the least suppressive on the three pathogenic micro-organisms, samples obtained from two subsequent fermentation process (samples fermented at 43 degrees C for 3 h and at 30 degrees C for 21 h) were more suppressive than that of traditional kefir. There was no significant survival difference between E. coli O157:H7 and L. monocytogenes 4b in samples tested (P > 0.05), but Y. enterocolitica O3 was more susceptible than other two test strains (P < 0.05). The microbiological safety of the dairy product fermented at two consecutive periods was superior than that of traditional yogurt or kefir alone. These experiments may mimic what happens when yogurt and kefir starter micro-organisms are combined in a milk fermentation process with different time and temperature periods.

Use of Whole-Genus Genome Sequence Data To Develop a Multilocus Sequence Typing Tool That Accurately Identifies Yersinia Isolates to the Species and Subspecies Levels

PubMed Central

Hall, Miquette; Chattaway, Marie A.; Reuter, Sandra; Savin, Cyril; Strauch, Eckhard; Carniel, Elisabeth; Connor, Thomas; Van Damme, Inge; Rajakaruna, Lakshani; Rajendram, Dunstan; Jenkins, Claire; Thomson, Nicholas R.

2014-01-01

The genus Yersinia is a large and diverse bacterial genus consisting of human-pathogenic species, a fish-pathogenic species, and a large number of environmental species. Recently, the phylogenetic and population structure of the entire genus was elucidated through the genome sequence data of 241 strains encompassing every known species in the genus. Here we report the mining of this enormous data set to create a multilocus sequence typing-based scheme that can identify Yersinia strains to the species level to a level of resolution equal to that for whole-genome sequencing. Our assay is designed to be able to accurately subtype the important human-pathogenic species Yersinia enterocolitica to whole-genome resolution levels. We also report the validation of the scheme on 386 strains from reference laboratory collections across Europe. We propose that the scheme is an important molecular typing system to allow accurate and reproducible identification of Yersinia isolates to the species level, a process often inconsistent in nonspecialist laboratories. Additionally, our assay is the most phylogenetically informative typing scheme available for Y. enterocolitica. PMID:25339391

Resistance to amoxicillin-clavulanate and its relation to virulence-related factors in Yersinia enterocolitica biovar 1A.

PubMed

Singhal, N; Kumar, M; Virdi, J S

2016-01-01

Recent studies have reported that the virulence factors (VFs) were detected more frequently in amoxicillin-clavulanate (AMC) susceptible clinical isolates of Escherichia coli. Here, we have evaluated the relationship between VFs and AMC-resistance phenotype in clinical isolates of Y. enterocolitica biovar 1A. The presence/absence of VFs was compared with their minimum inhibitory concentrations for AMC in strains of two serovars. We observed that the strains of the serovar O: 6, 30-6, 31 showed a similar relationship between the number of VFs and resistance to clavulanic acid as in E. coli but not of serovar O: 6, 30. Variations in the promoters/complete coding sequences (CCDSs) of β-lactamase gene (bla A) or the serological characteristics could not account for unusual susceptibility to AMC displayed by the strains of the serovar O: 6, 30. Therefore, we speculate that since the clinical strains of serovar O: 6, 30-6, 31 originated from the environment they were less exposed to antibiotics compared to clinical strains of serovar O: 6, 30. Thus, AMC susceptibility seems to be influenced by factors other than serotypes or promoters/CCDS of β-lactamase genes.

Coregulation of host-adapted metabolism and virulence by pathogenic yersiniae

PubMed Central

Heroven, Ann Kathrin; Dersch, Petra

2014-01-01

Deciphering the principles how pathogenic bacteria adapt their metabolism to a specific host microenvironment is critical for understanding bacterial pathogenesis. The enteric pathogenic Yersinia species Yersinia pseudotuberculosis and Yersinia enterocolitica and the causative agent of plague, Yersinia pestis, are able to survive in a large variety of environmental reservoirs (e.g., soil, plants, insects) as well as warm-blooded animals (e.g., rodents, pigs, humans) with a particular preference for lymphatic tissues. In order to manage rapidly changing environmental conditions and interbacterial competition, Yersinia senses the nutritional composition during the course of an infection by special molecular devices, integrates this information and adapts its metabolism accordingly. In addition, nutrient availability has an impact on expression of virulence genes in response to C-sources, demonstrating a tight link between the pathogenicity of yersiniae and utilization of nutrients. Recent studies revealed that global regulatory factors such as the cAMP receptor protein (Crp) and the carbon storage regulator (Csr) system are part of a large network of transcriptional and posttranscriptional control strategies adjusting metabolic changes and virulence in response to temperature, ion and nutrient availability. Gained knowledge about the specific metabolic requirements and the correlation between metabolic and virulence gene expression that enable efficient host colonization led to the identification of new potential antimicrobial targets. PMID:25368845

Yersinia Type III Secretion System Master Regulator LcrF

PubMed Central

Schwiesow, Leah; Lam, Hanh

2015-01-01

Many Gram-negative pathogens express a type III secretion (T3SS) system to enable growth and survival within a host. The three human-pathogenic Yersinia species, Y. pestis, Y. pseudotuberculosis, and Y. enterocolitica, encode the Ysc T3SS, whose expression is controlled by an AraC-like master regulator called LcrF. In this review, we discuss LcrF structure and function as well as the environmental cues and pathways known to regulate LcrF expression. Similarities and differences in binding motifs and modes of action between LcrF and the Pseudomonas aeruginosa homolog ExsA are summarized. In addition, we present a new bioinformatics analysis that identifies putative LcrF binding sites within Yersinia target gene promoters. PMID:26644429

Prevalence and antimicrobial resistance of Listeria, Salmonella, and Yersinia species isolates in ducks and geese.

PubMed

Jamali, Hossein; Radmehr, Behrad; Ismail, Salmah

2014-04-01

The aims of this study were to determine the prevalence and antimicrobial resistance of Listeria, Salmonella, and Yersinia spp. isolated from duck and goose intestinal contents. A total of 471 samples, including 291 duck and 180 goose intestinal contents, were purchased from wet markets between November 2008 and July 2010. Listeria, Salmonella, and Yersinia spp. were isolated from 58 (12.3%), 107 (22.7%), and 80 (17%) of the samples, respectively. It was concluded that Listeria ivanovii, Salmonella Thompson, and Yersinia enterocolitica were the predominant serovars among Listeria, Salmonella, and Yersinia spp., respectively. Moreover, resistance to tetracycline was common in Listeria (48.3%) and Salmonella spp. (63.6%), whereas 51.3% of the Yersinia spp. isolates were resistant to cephalothin. Therefore, continued surveillance of the prevalence of the pathogens and also of emerging antibiotic resistance is needed to render possible the recognition of foods that may represent risks and also ensure the effective treatment of listeriosis, salmonellosis, and yersiniosis.

Yersinia virulence factors - a sophisticated arsenal for combating host defences

PubMed Central

Atkinson, Steve; Williams, Paul

2016-01-01

The human pathogens Yersinia pseudotuberculosis and Yersinia enterocolitica cause enterocolitis, while Yersinia pestis is responsible for pneumonic, bubonic, and septicaemic plague. All three share an infection strategy that relies on a virulence factor arsenal to enable them to enter, adhere to, and colonise the host while evading host defences to avoid untimely clearance. Their arsenal includes a number of adhesins that allow the invading pathogens to establish a foothold in the host and to adhere to specific tissues later during infection. When the host innate immune system has been activated, all three pathogens produce a structure analogous to a hypodermic needle. In conjunction with the translocon, which forms a pore in the host membrane, the channel that is formed enables the transfer of six ‘effector’ proteins into the host cell cytoplasm. These proteins mimic host cell proteins but are more efficient than their native counterparts at modifying the host cell cytoskeleton, triggering the host cell suicide response. Such a sophisticated arsenal ensures that yersiniae maintain the upper hand despite the best efforts of the host to counteract the infecting pathogen. PMID:27347390

Growth of Listeria monocytogenes and Yersinia enterocolitica colonies under modified atmospheres at 4 and 8 degrees C using a model food system.

PubMed

Harrison, W A; Peters, A C; Fielding, L M

2000-01-01

The growth of Listeria monocytogenes and Yersinia enterocolitica colonies was studied on solid media at 4 and 8 degrees C under modified atmospheres (MAs) of 5% O2: 10% CO2: 85% N2 (MA1), 30% CO2: 70% N2 (MA2) and air (control). Colony radius, determined using computer image analysis, allowed specific growth rates (mu) and the time taken to detect bacterial colonies to be estimated, after colonies became visible. At 4 degrees C both MAs decreased the growth rates of L. monocytogenes by 1.5- and 3.0-fold under MA1 (mu = 0.02 h(-1)) and MA2 (mu = 0.01 h(-1)), respectively, as compared with the control (mu = 0.03 h(-1)). The time to detection of bacterial colonies was increased from 15 d (control) to 24 (MA1) and 29 d (MA2). At 8 degrees C MA2 decreased the growth rate by 1.5-fold (mu = 0.04 h(-1)) as compared with the control (mu = 0.06 h(-1)) and detection of colonies increased from 7 (control) to 9 d (MA2). At 4 degrees C both MAs decreased the growth rates of Y. enterocolitica by 1.5- and 2.5-fold under MA1 (mu = 0.03 h(-1)) and MA2 (mu = 0.02 h(-1)), respectively, as compared with the control (mu = 0.05 h(-1)). At 8 degrees C identical growth rates were obtained under MA1 and the control (mu = 0.07 h(-1)) whilst a decrease in the growth rate was obtained under MA2 (mu = 0.04 h(-1)). The detection of colonies varied from 6 (8 degrees C, aerobic) to 19 d (4 degrees C, MA2). Refrigerated modified atmosphere packaged foods should be maintained at 4 degrees C and below to ensure product safety.

RovA, a global regulator of Yersinia pestis, specifically required for bubonic plague.

PubMed

Cathelyn, Jason S; Crosby, Seth D; Lathem, Wyndham W; Goldman, William E; Miller, Virginia L

2006-09-05

The pathogenic species of Yersinia contain the transcriptional regulator RovA. In Yersinia pseudotuberculosis and Yersinia enterocolitica, RovA regulates expression of the invasion factor invasin (inv), which mediates translocation across the intestinal epithelium. A Y. enterocolitica rovA mutant has a significant decrease in virulence by LD(50) analysis and an altered rate of dissemination compared with either wild type or an inv mutant, suggesting that RovA regulates multiple virulence factors. Here, we show the involvement of RovA in the virulence of Yersinia pestis, which naturally lacks a functional inv gene. A Y. pestis DeltarovA mutant is attenuated approximately 80-fold by LD(50) and is defective in dissemination/colonization of spleens and lungs after s.c. inoculation. However, the DeltarovA mutant is only slightly attenuated when given via an intranasal or i.p. route, indicating a more important role for RovA in bubonic plague than pneumonic plague or systemic infection. Microarray analysis was used to define the RovA regulon. The psa locus was among the most highly down-regulated loci in the DeltarovA mutant. A DeltapsaA mutant had a significant dissemination defect after s.c. infection but only slight attenuation by the pneumonic-disease model, closely mimicking the virulence defect seen with the DeltarovA mutant. DNA-binding studies revealed that RovA specifically interacts with the psaE and psaA promoter regions, indicating a direct role for RovA in regulating this locus. Thus, RovA appears to be a global transcription factor in Y. pestis and, through its regulatory influence on genes such as psaEFABC, contributes to the virulence of Y. pestis.

Proteomic Characterization of Host Response to Yersinia pestis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chromy, B; Perkins, J; Heidbrink, J

Host-pathogen interactions result in protein expression changes within both the host and the pathogen. Here, results from proteomic characterization of host response following exposure to Yersinia pestis, the causative agent of plague, and to two near neighbors, Y. pseudotuberculosis and Y. enterocolitica, are reported. Human monocyte-like cells were chosen as a model for macrophage immune response to pathogen exposure. Two-dimensional electrophoresis followed by mass spectrometry was used to identify host proteins with differential expression following exposure to these three closely related Yersinia species. This comparative proteomic characterization of host response clearly shows that host protein expression patterns are distinct formore » the different pathogen exposures, and contributes to further understanding of Y. pestis virulence and host defense mechanisms. This work also lays the foundation for future studies aimed at defining biomarkers for presymptomatic detection of plague.« less

Isolation of Yersinia from raw meat (pork and chicken) and precooked meat (porcine tongues and sausages) collected from commercial establishments in Mexico City.

PubMed

Ramírez, E I; Vázquez-Salinas, C; Rodas-Suárez, O R; Pedroche, F F

2000-04-01

A total of 160 meat product samples were collected from commercial outlets in Mexico City to investigate the presence of different species of Yersinia by the 4 degrees C enrichment method after 1, 3, 5, and 7 days of incubation using alkaline treatment and isolating in cefsulodin-Irgasan-novobiocin and MacConkey agars with Tween 80. Overall, Yersinia spp. were isolated from 27% of the samples analyzed, whereas 40% of the raw and only 13% of the precooked samples were contaminated. Although 2,970 colonies showed Yersinia characteristics, only 706 (24%) actually corresponded to this genus: 49% were Yersinia enterocolitica, 25% Yersinia kristensenii, 15% Yersinia intermedia, 9% Yersinia frederiksenii, and 2% Yersinia aldovae; 10% corresponded to biotype 2, 2% to biotype 3, and 4% to biotype 4. The presence of Yersinia in raw and cooked meat products represents a health risk for consumers in Mexico, where further clinical studies are needed to assess the epidemiological importance of this pathogen.

Control of human pathogenic Yersinia enterocolitica in minced meat: Comparative analysis of different interventions using a risk assessment approach.

PubMed

Van Damme, I; De Zutter, L; Jacxsens, L; Nauta, M J

2017-06-01

This study aimed to evaluate the effect of different processing scenarios along the farm-to-fork chain on the contamination of minced pork with human pathogenic Y. enterocolitica. A modular process risk model (MPRM) was used to perform the assessment of the concentrations of pathogenic Y. enterocolitica in minced meat produced in industrial meat processing plants. The model described the production of minced pork starting from the contamination of pig carcasses with pathogenic Y. enterocolitica just before chilling. The endpoints of the assessment were (i) the proportion of 0.5 kg minced meat packages that contained pathogenic Y. enterocolitica and (ii) the proportion of 0.5 kg minced meat packages that contained more than 10³ pathogenic Y. enterocolitica at the end of storage, just before consumption of raw pork or preparation. Comparing alternative scenarios to the baseline model showed that the initial contamination and different decontamination procedures of carcasses have an important effect on the proportion of highly contaminated minced meat packages at the end of storage. The addition of pork cheeks and minimal quantities of tonsillar tissue into minced meat also had a large effect on the endpoint estimate. Finally, storage time and temperature at consumer level strongly influenced the number of highly contaminated packages. Copyright © 2016 Elsevier Ltd. All rights reserved.

The Yersinia pseudotuberculosis and Yersinia pestis toxin complex is active against cultured mammalian cells.

PubMed

Hares, Michelle C; Hinchliffe, Stewart J; Strong, Philippa C R; Eleftherianos, Ioannis; Dowling, Andrea J; ffrench-Constant, Richard H; Waterfield, Nick

2008-11-01

The toxin complex (Tc) genes were first identified in the insect pathogen Photorhabdus luminescens and encode approximately 1 MDa protein complexes which are toxic to insect pests. Subsequent genome sequencing projects have revealed the presence of tc orthologues in a range of bacterial pathogens known to be associated with insects. Interestingly, members of the mammalian-pathogenic yersiniae have also been shown to encode Tc orthologues. Studies in Yersinia enterocolitica have shown that divergent tc loci either encode insect-active toxins or play a role in colonization of the gut in gastroenteritis models of rats. So far little is known about the activity of the Tc proteins in the other mammalian-pathogenic yersiniae. Here we present work to suggest that Tc proteins in Yersinia pseudotuberculosis and Yersinia pestis are not insecticidal toxins but have evolved for mammalian pathogenicity. We show that Tc is secreted by Y. pseudotuberculosis strain IP32953 during growth in media at 28 degrees C and 37 degrees C. We also demonstrate that oral toxicity of strain IP32953 to Manduca sexta larvae is not due to Tc expression and that lysates of Escherichia coli BL21 expressing the Yersinia Tc proteins are not toxic to Sf9 insect cells but are toxic to cultured mammalian cell lines. Cell lysates of E. coli BL21 expressing the Y. pseudotuberculosis Tc proteins caused actin ruffles, vacuoles and multi-nucleation in cultured human gut cells (Caco-2); similar morphology was observed after application of a lysate of E. coli BL21 expressing the Y. pestis Tc proteins to mouse fibroblast NIH3T3 cells, but not Caco-2 cells. Finally, transient expression of the individual Tc proteins in Caco-2 and NIH3T3 cell lines reproduced the actin and nuclear rearrangement observed with the topical applications. Together these results add weight to the growing hypothesis that the Tc proteins in Y. pseudotuberculosis and Y. pestis have been adapted for mammalian pathogenicity. We further

Immunosuppressive Yersinia Effector YopM Binds DEAD Box Helicase DDX3 to Control Ribosomal S6 Kinase in the Nucleus of Host Cells.

PubMed

Berneking, Laura; Schnapp, Marie; Rumm, Andreas; Trasak, Claudia; Ruckdeschel, Klaus; Alawi, Malik; Grundhoff, Adam; Kikhney, Alexey G; Koch-Nolte, Friedrich; Buck, Friedrich; Perbandt, Markus; Betzel, Christian; Svergun, Dmitri I; Hentschke, Moritz; Aepfelbacher, Martin

2016-06-01

Yersinia outer protein M (YopM) is a crucial immunosuppressive effector of the plaque agent Yersinia pestis and other pathogenic Yersinia species. YopM enters the nucleus of host cells but neither the mechanisms governing its nucleocytoplasmic shuttling nor its intranuclear activities are known. Here we identify the DEAD-box helicase 3 (DDX3) as a novel interaction partner of Y. enterocolitica YopM and present the three-dimensional structure of a YopM:DDX3 complex. Knockdown of DDX3 or inhibition of the exportin chromosomal maintenance 1 (CRM1) increased the nuclear level of YopM suggesting that YopM exploits DDX3 to exit the nucleus via the CRM1 export pathway. Increased nuclear YopM levels caused enhanced phosphorylation of Ribosomal S6 Kinase 1 (RSK1) in the nucleus. In Y. enterocolitica infected primary human macrophages YopM increased the level of Interleukin-10 (IL-10) mRNA and this effect required interaction of YopM with RSK and was enhanced by blocking YopM's nuclear export. We propose that the DDX3/CRM1 mediated nucleocytoplasmic shuttling of YopM determines the extent of phosphorylation of RSK in the nucleus to control transcription of immunosuppressive cytokines.

Genome Wide Search for Biomarkers to Diagnose Yersinia Infections.

PubMed

Kalia, Vipin Chandra; Kumar, Prasun

2015-12-01

Bacterial identification on the basis of the highly conserved 16S rRNA (rrs) gene is limited by its presence in multiple copies and a very high level of similarity among them. The need is to look for other genes with unique characteristics to be used as biomarkers. Fifty-one sequenced genomes belonging to 10 different Yersinia species were used for searching genes common to all the genomes. Out of 304 common genes, 34 genes of sizes varying from 0.11 to 4.42 kb, were selected and subjected to in silico digestion with 10 different Restriction endonucleases (RE) (4-6 base cutters). Yersinia species have 6-7 copies of rrs per genome, which are difficult to distinguish by multiple sequence alignments or their RE digestion patterns. However, certain unique combinations of other common gene sequences-carB, fadJ, gluM, gltX, ileS, malE, nusA, ribD, and rlmL and their RE digestion patterns can be used as markers for identifying 21 strains belonging to 10 Yersinia species: Y. aldovae, Y. enterocolitica, Y. frederiksenii, Y. intermedia, Y. kristensenii, Y. pestis, Y. pseudotuberculosis, Y. rohdei, Y. ruckeri, and Y. similis. This approach can be applied for rapid diagnostic applications.

Yersinia type III effectors perturb host innate immune responses

PubMed Central

Pha, Khavong; Navarro, Lorena

2016-01-01

The innate immune system is the first line of defense against invading pathogens. Innate immune cells recognize molecular patterns from the pathogen and mount a response to resolve the infection. The production of proinflammatory cytokines and reactive oxygen species, phagocytosis, and induced programmed cell death are processes initiated by innate immune cells in order to combat invading pathogens. However, pathogens have evolved various virulence mechanisms to subvert these responses. One strategy utilized by Gram-negative bacterial pathogens is the deployment of a complex machine termed the type III secretion system (T3SS). The T3SS is composed of a syringe-like needle structure and the effector proteins that are injected directly into a target host cell to disrupt a cellular response. The three human pathogenic Yersinia spp. (Y. pestis, Y. enterocolitica, and Y. pseudotuberculosis) are Gram-negative bacteria that share in common a 70 kb virulence plasmid which encodes the T3SS. Translocation of the Yersinia effector proteins (YopE, YopH, YopT, YopM, YpkA/YopO, and YopP/J) into the target host cell results in disruption of the actin cytoskeleton to inhibit phagocytosis, downregulation of proinflammatory cytokine/chemokine production, and induction of cellular apoptosis of the target cell. Over the past 25 years, studies on the Yersinia effector proteins have unveiled tremendous knowledge of how the effectors enhance Yersinia virulence. Recently, the long awaited crystal structure of YpkA has been solved providing further insights into the activation of the YpkA kinase domain. Multisite autophosphorylation by YpkA to activate its kinase domain was also shown and postulated to serve as a mechanism to bypass regulation by host phosphatases. In addition, novel Yersinia effector protein targets, such as caspase-1, and signaling pathways including activation of the inflammasome were identified. In this review, we summarize the recent discoveries made on Yersinia

Trends of the Major Porin Gene (ompF) Evolution: Insight from the Genus Yersinia

PubMed Central

Stenkova, Anna M.; Isaeva, Marina P.; Shubin, Felix N.; Rasskazov, Valeri A.; Rakin, Alexander V.

2011-01-01

OmpF is one of the major general porins of Enterobacteriaceae that belongs to the first line of bacterial defense and interactions with the biotic as well as abiotic environments. Porins are surface exposed and their structures strongly reflect the history of multiple interactions with the environmental challenges. Unfortunately, little is known on diversity of porin genes of Enterobacteriaceae and the genus Yersinia especially. We analyzed the sequences of the ompF gene from 73 Yersinia strains covering 14 known species. The phylogenetic analysis placed most of the Yersinia strains in the same line assigned by 16S rDNA-gyrB tree. Very high congruence in the tree topologies was observed for Y. enterocolitica, Y. kristensenii, Y. ruckeri, indicating that intragenic recombination in these species had no effect on the ompF gene. A significant level of intra- and interspecies recombination was found for Y. aleksiciae, Y. intermedia and Y. mollaretii. Our analysis shows that the ompF gene of Yersinia has evolved with nonrandom mutational rate under purifying selection. However, several surface loops in the OmpF porin contain positively selected sites, which very likely reflect adaptive diversification Yersinia to their ecological niches. To our knowledge, this is a first investigation of diversity of the porin gene covering the whole genus of the family Enterobacteriaceae. This study demonstrates that recombination and positive selection both contribute to evolution of ompF, but the relative contribution of these evolutionary forces are different among Yersinia species. PMID:21655186

Phylogeographic separation and formation of sexually discrete lineages in a global population of Yersinia pseudotuberculosis

PubMed Central

Seecharran, Tristan; Kalin-Manttari, Laura; Koskela, Katja; Nikkari, Simo; Dickins, Benjamin; Corander, Jukka; Skurnik, Mikael

2017-01-01

Yersinia pseudotuberculosis is a Gram-negative intestinal pathogen of humans and has been responsible for several nationwide gastrointestinal outbreaks. Large-scale population genomic studies have been performed on the other human pathogenic species of the genus Yersinia, Yersinia pestis and Yersinia enterocolitica allowing a high-resolution understanding of the ecology, evolution and dissemination of these pathogens. However, to date no purpose-designed large-scale global population genomic analysis of Y. pseudotuberculosis has been performed. Here we present analyses of the genomes of 134 strains of Y. pseudotuberculosis isolated from around the world, from multiple ecosystems since the 1960s. Our data display a phylogeographic split within the population, with an Asian ancestry and subsequent dispersal of successful clonal lineages into Europe and the rest of the world. These lineages can be differentiated by CRISPR cluster arrays, and we show that the lineages are limited with respect to inter-lineage genetic exchange. This restriction of genetic exchange maintains the discrete lineage structure in the population despite co-existence of lineages for thousands of years in multiple countries. Our data highlights how CRISPR can be informative of the evolutionary trajectory of bacterial lineages, and merits further study across bacteria. PMID:29177091

Catalytically active Yersinia outer protein P induces cleavage of RIP and caspase-8 at the level of the DISC independently of death receptors in dendritic cells.

PubMed

Gröbner, Sabine; Adkins, Irena; Schulz, Sebastian; Richter, Kathleen; Borgmann, Stefan; Wesselborg, Sebastian; Ruckdeschel, Klaus; Micheau, Olivier; Autenrieth, Ingo B

2007-10-01

Yersinia outer protein P (YopP) is injected by Y. enterocolitica into host cells thereby inducing apoptotic and necrosis-like cell death in dendritic cells (DC). Here we show the pathways involved in DC death caused by the catalytic activity of YopP. Infection with Yersinia enterocolitica, translocating catalytically active YopP into DC, triggered procaspase-8 cleavage and c-FLIPL degradation. YopP-dependent caspase-8 activation was, however, not mediated by tumor necrosis factor (TNF) receptor family members since the expression of both CD95/Fas/APO-1 and TRAIL-R2 on DC was low, and DC were resistant to apoptosis induced by agonistic anti-CD95 antibodies or TNF-related apoptosis-inducing ligand (TRAIL). Moreover, DC from TNF-Rp55-/- mice were not protected against YopP-induced cell death demonstrating that TNF-R1 is also not involved in this process. Activation of caspase-8 was further investigated by coimmunoprecitation of FADD from Yersinia-infected DC. We found that both cleaved caspase-8 and receptor interacting protein 1 (RIP1) were associated with the Fas-associated death domain (FADD) indicating the formation of an atypical death-inducing signaling complex (DISC). Furthermore, degradation of RIP mediated by the Hsp90 inhibitor geldanamycin significantly impaired YopP-induced cell death. Altogether our findings indicate that Yersinia-induced DC death is independent of death domain containing receptors, but mediated by RIP and caspase-8 at the level of DISC.

Thirty-Two Complete Genome Assemblies of Nine Yersinia Species, Including Y. pestis, Y. pseudotuberculosis, and Y. enterocolitica

DOE PAGES

Johnson, Shannon L.; Daligault, Hajnalka E.; Davenport, Karen W.; ...

2015-04-30

The genus Yersinia includes three human pathogens, of which Yersinia pestis is responsible for >2,000 illnesses each year. To aid in the development of detection assays as well as aid further phylogenetic elucidation, we sequenced and assembled the complete genomes of 32 strains (across 9 Yersinia species).

National outbreak of Yersinia enterocolitica infections in military and civilian populations associated with consumption of mixed salad, Norway, 2014

PubMed Central

MacDonald, Emily; Einöder-Moreno, Margot; Borgen, Katrine; Thorstensen Brandal, Lin; Diab, Lore; Fossli, Øivind; Guzman Herrador, Bernardo; Hassan, Ammar Ali; Johannessen, Gro S; Johansen, Eva Jeanette; Jørgensen Kimo, Roger; Lier, Tore; Paulsen, Bjørn Leif; Popescu, Rodica; Tokle Schytte, Charlotte; Sæbø Pettersen, Kristin; Vold, Line; Ørmen, Øyvind; Wester, Astrid Louise; Wiklund, Marit; Nygård, Karin

2016-01-01

In May 2014, a cluster of Yersinia enterocolitica (YE) O9 infections was reported from a military base in northern Norway. Concurrently, an increase in YE infections in civilians was observed in the Norwegian Surveillance System for Communicable Diseases. We investigated to ascertain the extent of the outbreak and identify the source in order to implement control measures. A case was defined as a person with laboratory-confirmed YE O9 infection with the outbreak multilocus variable-number tandem repeat analysis (MLVA)-profile (5-6-9-8-9-9). We conducted a case–control study in the military setting and calculated odds ratios (OR) using logistic regression. Traceback investigations were conducted to identify common suppliers and products in commercial kitchens frequented by cases. By 28 May, we identified 133 cases, of which 117 were linked to four military bases and 16 were civilians from geographically dispersed counties. Among foods consumed by cases, multivariable analysis pointed to mixed salad as a potential source of illness (OR 10.26; 95% confidence interval (CI): 0.85–123.57). The four military bases and cafeterias visited by 14/16 civilian cases received iceberg lettuce or radicchio rosso from the same supplier. Secondary transmission cannot be eliminated as a source of infection in the military camps. The most likely source of the outbreak was salad mix containing imported radicchio rosso, due to its long shelf life. This outbreak is a reminder that fresh produce should not be discounted as a vehicle in prolonged outbreaks and that improvements are still required in the production and processing of fresh salad products. PMID:27588690

National outbreak of Yersinia enterocolitica infections in military and civilian populations associated with consumption of mixed salad, Norway, 2014.

PubMed

MacDonald, Emily; Einöder-Moreno, Margot; Borgen, Katrine; Thorstensen Brandal, Lin; Diab, Lore; Fossli, Øivind; Guzman Herrador, Bernardo; Hassan, Ammar Ali; Johannessen, Gro S; Johansen, Eva Jeanette; Jørgensen Kimo, Roger; Lier, Tore; Paulsen, Bjørn Leif; Popescu, Rodica; Tokle Schytte, Charlotte; Sæbø Pettersen, Kristin; Vold, Line; Ørmen, Øyvind; Wester, Astrid Louise; Wiklund, Marit; Nygård, Karin

2016-08-25

In May 2014, a cluster of Yersinia enterocolitica (YE) O9 infections was reported from a military base in northern Norway. Concurrently, an increase in YE infections in civilians was observed in the Norwegian Surveillance System for Communicable Diseases. We investigated to ascertain the extent of the outbreak and identify the source in order to implement control measures. A case was defined as a person with laboratory-confirmed YE O9 infection with the outbreak multilocus variable-number tandem repeat analysis (MLVA)-profile (5-6-9-8-9-9). We conducted a case-control study in the military setting and calculated odds ratios (OR) using logistic regression. Traceback investigations were conducted to identify common suppliers and products in commercial kitchens frequented by cases. By 28 May, we identified 133 cases, of which 117 were linked to four military bases and 16 were civilians from geographically dispersed counties. Among foods consumed by cases, multivariable analysis pointed to mixed salad as a potential source of illness (OR 10.26; 95% confidence interval (CI): 0.85-123.57). The four military bases and cafeterias visited by 14/16 civilian cases received iceberg lettuce or radicchio rosso from the same supplier. Secondary transmission cannot be eliminated as a source of infection in the military camps. The most likely source of the outbreak was salad mix containing imported radicchio rosso, due to its long shelf life. This outbreak is a reminder that fresh produce should not be discounted as a vehicle in prolonged outbreaks and that improvements are still required in the production and processing of fresh salad products. This article is copyright of The Authors, 2016.

Virulence plasmid (pYV)-associated expression of phenotypic virulent determinants in pathogenic Yersinia species: a convenient method for monitoring the presence of pYV under culture conditions and its application for...food

USDA-ARS?s Scientific Manuscript database

In Yersinia pestis, Y. pseudotuberculosis, and Y, enterocolitica, phenotypic expression of virulence plasmid (pYV: 70-kb)-associated genetic determinants may include low calcium response (Lcr, pin point colony, size = 0.36 mm), colony morphology (size = 1.13 mm), crystal violet (CV) binding (dark-v...

Virulence plasmid (pYV)-associated expression of phenotypic virulent determinants in pathogenic Yersinia species: a convenient method for monitoring the presence of pYV under culture conditions and its application for....food

USDA-ARS?s Scientific Manuscript database

In Yersinia pestis, Y. pseudotuberculosis, and Y, enterocolitica, phenotypic expression of several virulence plasmid (pYV: 70-kb)-associated genetic determinants may include low calcium response (Lcr, pin point colony, size = 0.36 mm), colony morphology (size = 1.13 mm), crystal violet (CV) binding...

Effects of urbanization on host-pathogen interactions, using Yersinia in house sparrows as a model

PubMed Central

Strubbe, Diederik; Teyssier, Aimeric; Salleh Hudin, Noraine; Van den Abeele, Anne-Marie; Cox, Ivo; Haesendonck, Roel; Delmée, Michel; Haesebrouck, Freddy; Pasmans, Frank; Lens, Luc; Martel, An

2017-01-01

Urbanization strongly affects biodiversity, altering natural communities and often leading to a reduced species richness. Yet, despite its increasingly recognized importance, how urbanization impacts on the health of individual animals, wildlife populations and on disease ecology remains poorly understood. To test whether, and how, urbanization-driven ecosystem alterations influence pathogen dynamics and avian health, we use house sparrows (Passer domesticus) and Yersinia spp. (pathogenic for passerines) as a case study. Sparrows are granivorous urban exploiters, whose western European populations have declined over the past decades, especially in highly urbanized areas. We sampled 329 house sparrows originating from 36 populations along an urbanization gradient across Flanders (Belgium), and used isolation combined with ‘matrix-assisted laser desorption ionization- time of flight mass spectrometry’ (MALDI-TOF MS) and PCR methods for detecting the presence of different Yersinia species. Yersinia spp. were recovered from 57.43% of the sampled house sparrows, of which 4.06%, 53.30% and 69.54% were identified as Y. pseudotuberculosis, Y. enterocolitica and other Yersinia species, respectively. Presence of Yersinia was related to the degree of urbanization, average daily temperatures and the community of granivorous birds present at sparrow capture locations. Body condition of suburban house sparrows was found to be higher compared to urban and rural house sparrows, but no relationships between sparrows’ body condition and presence of Yersinia spp. were found. We conclude that two determinants of pathogen infection dynamics, body condition and pathogen occurrence, vary along an urbanization gradient, potentially mediating the impact of urbanization on avian health. PMID:29281672

Effects of urbanization on host-pathogen interactions, using Yersinia in house sparrows as a model.

PubMed

Rouffaer, Lieze Oscar; Strubbe, Diederik; Teyssier, Aimeric; Salleh Hudin, Noraine; Van den Abeele, Anne-Marie; Cox, Ivo; Haesendonck, Roel; Delmée, Michel; Haesebrouck, Freddy; Pasmans, Frank; Lens, Luc; Martel, An

2017-01-01

Urbanization strongly affects biodiversity, altering natural communities and often leading to a reduced species richness. Yet, despite its increasingly recognized importance, how urbanization impacts on the health of individual animals, wildlife populations and on disease ecology remains poorly understood. To test whether, and how, urbanization-driven ecosystem alterations influence pathogen dynamics and avian health, we use house sparrows (Passer domesticus) and Yersinia spp. (pathogenic for passerines) as a case study. Sparrows are granivorous urban exploiters, whose western European populations have declined over the past decades, especially in highly urbanized areas. We sampled 329 house sparrows originating from 36 populations along an urbanization gradient across Flanders (Belgium), and used isolation combined with 'matrix-assisted laser desorption ionization- time of flight mass spectrometry' (MALDI-TOF MS) and PCR methods for detecting the presence of different Yersinia species. Yersinia spp. were recovered from 57.43% of the sampled house sparrows, of which 4.06%, 53.30% and 69.54% were identified as Y. pseudotuberculosis, Y. enterocolitica and other Yersinia species, respectively. Presence of Yersinia was related to the degree of urbanization, average daily temperatures and the community of granivorous birds present at sparrow capture locations. Body condition of suburban house sparrows was found to be higher compared to urban and rural house sparrows, but no relationships between sparrows' body condition and presence of Yersinia spp. were found. We conclude that two determinants of pathogen infection dynamics, body condition and pathogen occurrence, vary along an urbanization gradient, potentially mediating the impact of urbanization on avian health.

Adhesins of human pathogens from the genus Yersinia.

PubMed

Leo, Jack C; Skurnik, Mikael

2011-01-01

Bacteria of the Gram-negative genus Yersinia are environmentally ubiquitous. Three species are of medical importance: the intestinal pathogens Y. enterocolitica and Y. pseudotuberculosis, and the plague bacillus Y. pestis. The two former species, spread by contaminated food or water, cause a range of gastrointestinal symptoms and, rarely, sepsis. On occasion, the primary infection is followed by autoimmune sequelae such as reactive arthritis. Plague is a systemic disease with high mortality. It is a zoonosis spread by fleas, or more rarely by droplets from individuals suffering from pneumonic plague. Y. pestis is one of the most virulent of bacteria, and recent findings of antibiotic-resistant strains together with its potential use as a bioweapon have increased interest in the species. In addition to being significant pathogens in their own right, the yersiniae have been used as model systems for a number of aspects of pathogenicity. This chapter reviews the molecular mechanisms of adhesion in yersiniae. The enteropathogenic species share three adhesins: invasin, YadA and Ail. Invasin is the first adhesin required for enteric infection; it binds to β(1) integrins on microfold cells in the distal ileum, leading to the ingestion of the bacteria and allows them to cross the intestinal epithelium. YadA is the major adhesin in host tissues. It is a multifunctional protein, conferring adherence to cells and extracellular matrix components, serum and phagocytosis resistance, and the ability to autoagglutinate. Ail has a minor role in adhesion and serum resistance. Y. pestis lacks both invasin and YadA, but expresses several other adhesins. These include the pH 6 antigen and autotransporter adhesins. Also the plasminogen activator of Y. pestis can mediate adherence to host cells. Although the adhesins of the pathogenic yersiniae have been studied extensively, their exact roles in the biology of infection remain elusive.

YopJ-Induced Caspase-1 Activation in Yersinia-Infected Macrophages: Independent of Apoptosis, Linked to Necrosis, Dispensable for Innate Host Defense

PubMed Central

Zheng, Ying; Lilo, Sarit; Mena, Patricio; Bliska, James B.

2012-01-01

Yersinia outer protein J (YopJ) is a type III secretion system (T3SS) effector of pathogenic Yersinia (Yersinia pestis, Yersinia enterocolitica and Yersinia pseudotuberculosis) that is secreted into host cells. YopJ inhibits survival response pathways in macrophages, causing cell death. Allelic variation of YopJ is responsible for differential cytotoxicity in Yersinia strains. YopJ isoforms in Y. enterocolitica O:8 (YopP) and Y. pestis KIM (YopJKIM) strains have high cytotoxic activity. In addition, YopJKIM-induced macrophage death is associated with caspase-1 activation and interleukin-1β (IL-1β secretion. Here, the mechanism of YopJKIM-induced cell death, caspase-1 activation, and IL-1β secretion in primary murine macrophages was examined. Caspase-3/7 activity was low and the caspase-3 substrate poly (ADP-ribose) polymerase (PARP) was not cleaved in Y. pestis KIM5-infected macrophages. In addition, cytotoxicity and IL-1β secretion were not reduced in the presence of a caspase-8 inhibitor, or in B-cell lymphoma 2 (Bcl-2)-associated X protein (Bax)/Bcl-2 homologous antagonist/killer (Bak) knockout macrophages, showing that YopJKIM-mediated cell death and caspase-1 activation occur independent of mitochondrial-directed apoptosis. KIM5-infected macrophages released high mobility group protein B1 (HMGB1), a marker of necrosis, and microscopic analysis revealed that necrotic cells contained active caspase-1, indicating that caspase-1 activation is associated with necrosis. Inhibitor studies showed that receptor interacting protein 1 (RIP1) kinase and reactive oxygen species (ROS) were not required for cytotoxicity or IL-β release in KIM5-infected macrophages. IL-1β secretion was reduced in the presence of cathepsin B inhibitors, suggesting that activation of caspase-1 requires cathepsin B activity. Ectopically-expressed YopP caused higher cytotoxicity and secretion of IL-1β in Y. pseudotuberculosis-infected macrophages than YopJKIM. Wild-type and congenic

YopJ-induced caspase-1 activation in Yersinia-infected macrophages: independent of apoptosis, linked to necrosis, dispensable for innate host defense.

PubMed

Zheng, Ying; Lilo, Sarit; Mena, Patricio; Bliska, James B

2012-01-01

Yersinia outer protein J (YopJ) is a type III secretion system (T3SS) effector of pathogenic Yersinia (Yersinia pestis, Yersinia enterocolitica and Yersinia pseudotuberculosis) that is secreted into host cells. YopJ inhibits survival response pathways in macrophages, causing cell death. Allelic variation of YopJ is responsible for differential cytotoxicity in Yersinia strains. YopJ isoforms in Y. enterocolitica O:8 (YopP) and Y. pestis KIM (YopJ(KIM)) strains have high cytotoxic activity. In addition, YopJ(KIM)-induced macrophage death is associated with caspase-1 activation and interleukin-1β (IL-1β secretion. Here, the mechanism of YopJ(KIM)-induced cell death, caspase-1 activation, and IL-1β secretion in primary murine macrophages was examined. Caspase-3/7 activity was low and the caspase-3 substrate poly (ADP-ribose) polymerase (PARP) was not cleaved in Y. pestis KIM5-infected macrophages. In addition, cytotoxicity and IL-1β secretion were not reduced in the presence of a caspase-8 inhibitor, or in B-cell lymphoma 2 (Bcl-2)-associated X protein (Bax)/Bcl-2 homologous antagonist/killer (Bak) knockout macrophages, showing that YopJ(KIM)-mediated cell death and caspase-1 activation occur independent of mitochondrial-directed apoptosis. KIM5-infected macrophages released high mobility group protein B1 (HMGB1), a marker of necrosis, and microscopic analysis revealed that necrotic cells contained active caspase-1, indicating that caspase-1 activation is associated with necrosis. Inhibitor studies showed that receptor interacting protein 1 (RIP1) kinase and reactive oxygen species (ROS) were not required for cytotoxicity or IL-β release in KIM5-infected macrophages. IL-1β secretion was reduced in the presence of cathepsin B inhibitors, suggesting that activation of caspase-1 requires cathepsin B activity. Ectopically-expressed YopP caused higher cytotoxicity and secretion of IL-1β in Y. pseudotuberculosis-infected macrophages than YopJ(KIM). Wild-type and

Association between microbiological and serological prevalence of human pathogenic Yersinia spp. in pigs and pig batches.

PubMed

Vanantwerpen, Gerty; Berkvens, Dirk; De Zutter, Lieven; Houf, Kurt

2015-07-09

Pigs are the main reservoir of human pathogenic Y. enterocolitica, and the microbiological and serological prevalence of this pathogen differs between pig farms. The infection status of pig batches at moment of slaughter is unknown while it is a possibility to classify batches. A relation between the presence of human pathogenic Yersinia spp. and the presence of antibodies could help to predict the infection of the pigs prior to slaughter. Pigs from 100 different batches were sampled. Tonsils and pieces of diaphragm were collected from 7047 pigs (on average 70 pigs per batch). The tonsils were analyzed using a direct plating method and the meat juice collected from the pieces of diaphragm was analyzed by Enzyme Linked ImmunoSorbent Assay. The microbiological and serological results were compared using a mixed-effects logistic regression at pig and batch level. Yersinia spp. were found in 2031 (28.8%) pigs, antibodies were present in 4692 (66.6%) pigs. According to the logistic regression, there was no relation at pig level between the presence of Yersinia spp. in tonsils and the presence of antibodies. Contrarily, at batch level, a mean activity value of 37 Optical Density (OD)% indicated a Yersinia spp. positive farm and the microbiological prevalence in pig batches could be estimated before shipment to the slaughterhouse. This offers the opportunity to classify batches based on their potential risk to contaminate carcasses with human pathogenic Yersinia spp. Copyright © 2015 Elsevier B.V. All rights reserved.

Faecal bacteria of wild ruminants and the alpine marmot.

PubMed

Pagano, A; Nardi, G; Bonaccorso, C; Falbo, V; Passi, C; Sanguinetti, V; Mantovani, A

1985-07-01

Faecal samples from 60 red deer (Cervus elaphus), 13 roe deer (Capreolus capreolus), 7 chamois (Rupicapra rupicapra), 41 alpine marmot (Marmota marmota) and soils mixed with deer faeces from the Stelvio National Park were examined for Campylobacter sp. and Salmonella sp. with negative results. The same material, especially deer faeces, was a habitat highly suitable for Yersinia sp.: Y. enterocolitica (two biotypes) was isolated twice, Y. kristensenii (two serotypes) was isolated 19 times, Y. frederiksenii and Y. intermedia were isolated once. Antibiotic-resistant Escherichia coli were isolated from 16 specimens from wild ruminants, one from marmot and two from feeding places.

Acquisition of omptin reveals cryptic virulence function of autotransporter YapE in Yersinia pestis

PubMed Central

Pennington, Jarrod; Miller, Virginia L.

2013-01-01

SUMMARY Autotransporters, the largest family of secreted proteins in Gram negative bacteria, perform a variety of functions, including adherence, cytotoxicity, and immune evasion. In Yersinia pestis the autotransporter YapE has adhesive properties and contributes to bubonic infection of the mouse model. Here, we demonstrate that omptin cleavage of Y. pestis YapE is required to mediate bacterial aggregation and adherence to eukaryotic cells. We demonstrate that omptin cleavage is specific for the Y. pestis and Y. pseudotuberculosis YapE orthologs but is not conserved in the Y. enterocolitica protein. We also show that cleavage of YapE occurs in Y. pestis but not in the enteric Yersinia species, and requires the omptin Pla (plasminogen activator protease), which is encoded on the Y. pestis-specific plasmid pPCP1. Together, these data show that post-translation modification of YapE appears to be specific to Y. pestis, was acquired along with the acquisition of pPCP1 during the divergence of Y. pestis from Y. pseudotuberculosis, and are the first evidence of a novel mechanism to regulate bacterial adherence. PMID:23701256

Plague and other human infections caused by Yersinia species.

PubMed

Putzker, M; Sauer, H; Sobe, D

2001-01-01

With an estimated 100 million victims, pandemically and epidemically occurring plague has been looked upon as a classical scourge of mankind during the last two millenia. Without treatment at least 50% of the affected individuals die from infection with Yersinia pestis, a bacterium belonging to the family of Enterobacteriaceae. The disease takes a fulminant course. After an incubation period of 2-6 days, bubonic plague primarily attacks one group of lymph nodes. The onset of pulmonic plague, transmitted by droplet infection, takes place within several hours and causes bronchopneumonia. Early recognition facilitates a promising antibiotic therapy with tetracycline, streptomycin or chloramphenicol. Human beings acquire the bacteria through bites of fleas from domestic rats in densely populated cities of countries with low hygienic standards, or sporadically in the open country from infected wild rodents. Laboratory procedure includes microscopy supplemented by immunofluorescence and cultivation of the bacterium from clinical material. Direct serology and PCR result in a fast detection of specific antigens or nucleotide sequences. Determination of serum antibodies is principally used for epidemiological investigation. Today, physicians in the civilized western world lack experience for the recognition of plague, and analytical techniques for diagnosis are only available in some specialized laboratories. Yersiniosis becomes primarily manifest as gastroenteritis caused by Yersinia enterocolitica or as pseudoappendicitis caused by Yersinia pseudotuberculosis and requires antibiotics only in severe septic cases. Different extraintestinal symptoms may be observed in dependence on the patient's HLA type and gender. The ubiquitous germ is mainly transmitted by the fecal-oral route via infected domestic or farm animals and contaminated food. The relevant virulence factors are encoded on a 70 kB plasmid common to all Yersinia species and strains that are human pathogens. The

Potential wildlife sources of Yersinia pseudotuberculosis for farmed deer (Cervus elaphus).

PubMed

Mackintosh, C G; Henderson, T

1984-12-01

During 1982 and 1983 15 serotype I, 6 serotype II, 1 serotype III and 3 untyped strains of Yersinia pseudotuberculosis were isolated from 675 apparently normal small mammals and birds from the Invermay farm and nearby rubbish tip with the following prevalence rates: feral cats 27.8%, Norway rats 8.6%, mice 5.5%, hares 3.8% rabbits 1.9% ducks 5.3%, sparrows 2.3%, seagulls 2.3% and starlings 1.7%. For rabbits a significantly higher prevalence of infection was found in the autumn/winter period (4.8%) than the spring/summer period (0%). Insufficient numbers of other mammals were obtained to demonstrate any seasonal difference in prevalence. All bird isolations were obtained between March and July (8/158) compared with none from August to October (0/144). It appears that a number of free-living species of small mammal and birds may be reservoir hosts for Y. pseudotuberculosis and potential sources of infection for red deer on the Invermay farm.

Definition of a Standard Protocol to Determine the Growth Potential of Listeria Monotgenes and Yersinia Enterocolitica in Pork Sausage Produced in Abruzzo Region, Italy

PubMed Central

Neri, Diana; Romantini, Romina; Santarelli, Gino Angelo; Prencipe, Vincenza

2014-01-01

Pork meat products consumed raw or after a short period of fermentation can be considered at risk for food safety. Sausages (fresh sausage made from pork meat) are produced in several Italian regions, with variation in ingredients. In some Italian Regions, including Abruzzo, these products are frequently consumed raw or undercooked, after a variable period of fermentation. The European Community food regulation promotes the use of challenge tests to determine safety levels. This study is aimed to ensure safety of Abruzzo’s sausages, compared with growth potential (δ) of Listeria monocytogenes and Yersinia enterocolitica, and also aims to define an experimental standard protocol document to carry out challenge tests. Guidelines classify ready-to-eat foods in categories that are able to support (δ>0.5 log10 ufc/g) and not support (δ≤0.5 log10 ufc/g) the growth of Listeria monocytogenes. The products were manufactured according to traditional recipes and were contaminated in laboratory. Results from the experiment yielded information useful to assess the ability of these products to support the growth of pathogenic microorganisms. The batches of sausages were stored at 8, 12, 18 and 20°C to get statistical evaluation. The results showed that, despite the conditioning of the storage temperature and the level of water activity, both organisms remain in the product in concentrations similar to those leading or being able to increase its charge. In particular, the period of greatest consumption of this product (7/8 days of preparation) corresponds to the period of greatest growth of pathogenic microorganisms studied, except for those stored at a temperature of 8°C, which are safer for the consumer. PMID:27800415

Virulence characteristics of Yersinia pseudotuberculosis isolated from breeding monkeys in Japan.

PubMed

Iwata, Taketoshi; Une, Yumi; Okatani, Alexandre Tomomitsu; Kato, Yukio; Nakadai, Aya; Lee, Ken-Ichi; Watanabe, Maiko; Taniguchi, Takahide; Elhelaly, AbdelAzim Elsayed; Hirota, Yoshikazu; Hayashidani, Hideki

2008-06-22

Between April 2001 and 2007, 18 Yersinia pseudotuberculosis outbreaks occurred in breeding monkeys at 12 zoological gardens in Japan, and 28 monkeys of 8 species died. A total of 18 Y. pseudotuberculosis strains from the dead monkeys, comprising one strain per outbreak, were examined for serotype and the presence of the virulence genes virF, inv, ypm (ypmA, ypmB and ypmC) and irp2. Of the 18 Y. pseudotuberculosis strains, 7 (38.9%) were serotype 4b, 7 (38.9%) were serotype 1b, and there was one each of serotypes 2b, 3, 6 and 7. All the 18 strains examined harbored virF and inv. Sixteen (88.9%) strains, including the strain of serotype 7, harbored ypmA. However, no strain harbored ypmB, ypmC and irp2. This study demonstrated that among other pathogenic factors, almost all the Y. pseudotuberculosis isolated from the outbreaks had the ypm gene encoding the superantigenic toxin, YPM. As most of the monkeys who died in those outbreaks originated from South America and other regions, where the presence of the ypm gene have not been reported, YPM might be the cause, or at least the most important factor for, the high mortality of the breeding monkeys infected by Y. pseudotuberculosis in Japan. This is also the first report of a fatal case due to Y. pseudotuberculosis serotype 7 infection in the world.

X-ray crystal structures of the pheromone-binding domains of two quorum-hindered transcription factors, YenR of Yersinia enterocolitica and CepR2 of Burkholderia cenocepacia: KIM et al.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Youngchang; Chhor, Gekleng; Tsai, Ching-Sung

The ability of LuxR-type proteins to regulate transcription is controlled by bacterial pheromones, N-acylhomoserine lactones (AHLs). Most LuxR-family proteins require their cognate AHLs for activity, and some of them require AHLs for folding and stability, and for protease-resistance. However, a few members of this family are able to fold, dimerize, bind DNA, and regulate transcription in the absence of AHLs; moreover, these proteins are antagonized by their cognate AHLs. One such protein is YenR of Yersinia enterocolitica, which is antagonized by N-3-oxohexanoyl-l-homoserine lactone (OHHL). This pheromone is produced by the OHHL synthase, a product of the adjacent yenI gene. Anothermore » example is CepR2 of Burkholderia cenocepacia, which is antagonized by N-octanoyl-l-homoserine lactone (OHL), whose synthesis is directed by the cepI gene of the same bacterium. Here, we describe the high-resolution crystal structures of the AHL binding domains of YenR and CepR2. YenR was crystallized in the presence and absence of OHHL. While this ligand does not cause large scale changes in the YenR structure, it does alter the orientation of several highly conserved YenR residues within and near the pheromone-binding pocket, which in turn caused a significant movement of a surface-exposed loop.« less

Molecular characterization of the Salmonella typhi StpA protein that is related to both Yersinia YopE cytotoxin and YopH tyrosine phosphatase.

PubMed

Arricau, N; Hermant, D; Waxin, H; Popoff, M Y

1997-01-01

Analysis of the nucleotide sequence of a 4-kb DNA fragment located between the sip and iag loci on Salmonella typhi chromosome revealed three open reading frames, termed sipF, ctpA and stpA. The 82-amino-acid (aa) sipF product showed extensive similarity to the lacP protein from S. typhimurium. The StpA protein (535 aa) exhibited significant similarity to both Yersinia enterocolitica YopE cytotoxin and YopH tyrosine phosphatase. The CtpA polypeptide (130 aa) might be the molecular chaperone of the StpA protein.

Detection and Characterization of Shiga Toxin Producing Escherichia coli, Salmonella spp., and Yersinia Strains from Human, Animal, and Food Samples in San Luis, Argentina

PubMed Central

Favier, Gabriela Isabel; Lucero Estrada, Cecilia; Cortiñas, Teresa Inés; Escudero, María Esther

2014-01-01

Shiga toxin producing Escherichia coli (STEC), Salmonella spp., and Yersinia species was investigated in humans, animals, and foods in San Luis, Argentina. A total of 453 samples were analyzed by culture and PCR. The antimicrobial susceptibility of all the strains was studied, the genomic relationships among isolates of the same species were determined by PFGE, and the potencial virulence of Y. enterocolitica strains was analyzed. Yersinia species showed higher prevalence (9/453, 2.0%, 95% CI, 0.7–3.3%) than STEC (4/453, 0.9%, 95% CI, 0–1.8%) and Salmonella spp. (3/453, 0.7%, 95% CI, 0–1.5%). Y. enterocolitica and Y. intermedia were isolated from chicken carcasses (6/80, 7.5%, 95% CI, 1.5–13.5%) and porcine skin and bones (3/10, 30%, 95% CI, 0–65%). One STEC strain was recovered from human feces (1/70, 1.4%, 95% CI, 0–4.2%) and STEC stx1/stx2 genes were detected in bovine stools (3/129, 2.3%, 95% CI, 0–5.0%). S. Typhimurium was isolated from human feces (1/70, 1.4%, 95% CI, 0–4.2%) while one S. Newport and two S. Gaminara strains were recovered from one wild boar (1/3, 33%, 95% CI, 0–99%). The knowledge of prevalence and characteristics of these enteropathogens in our region would allow public health services to take adequate preventive measures. PMID:25177351

Yersinia ruckeri Isolates Recovered from Diseased Atlantic Salmon (Salmo salar) in Scotland Are More Diverse than Those from Rainbow Trout (Oncorhynchus mykiss) and Represent Distinct Subpopulations

PubMed Central

Ormsby, Michael J.; Caws, Thomas; Burchmore, Richard; Wallis, Tim; Verner-Jeffreys, David W.

2016-01-01

ABSTRACT Yersinia ruckeri is the etiological agent of enteric redmouth (ERM) disease of farmed salmonids. Enteric redmouth disease is traditionally associated with rainbow trout (Oncorhynchus mykiss, Walbaum), but its incidence in Atlantic salmon (Salmo salar) is increasing. Yersinia ruckeri isolates recovered from diseased Atlantic salmon have been poorly characterized, and very little is known about the relationship of the isolates associated with these two species. Phenotypic approaches were used to characterize 109 Y. ruckeri isolates recovered over a 14-year period from infected Atlantic salmon in Scotland; 26 isolates from infected rainbow trout were also characterized. Biotyping, serotyping, and comparison of outer membrane protein profiles identified 19 Y. ruckeri clones associated with Atlantic salmon but only five associated with rainbow trout; none of the Atlantic salmon clones occurred in rainbow trout and vice versa. These findings suggest that distinct subpopulations of Y. ruckeri are associated with each species. A new O serotype (designated O8) was identified in 56 biotype 1 Atlantic salmon isolates and was the most common serotype identified from 2006 to 2011 and in 2014, suggesting an increased prevalence during the time period sampled. Rainbow trout isolates were represented almost exclusively by the same biotype 2, serotype O1 clone that has been responsible for the majority of ERM outbreaks in this species within the United Kingdom since the 1980s. However, the identification of two biotype 2, serotype O8 isolates in rainbow trout suggests that vaccines containing serotypes O1 and O8 should be evaluated in both rainbow trout and Atlantic salmon for application in Scotland. IMPORTANCE Vaccination plays an important role in protecting Atlantic salmon against the bacterial pathogen Yersinia ruckeri, but, in recent years, there has been an increasing incidence of vaccine breakdown in salmon. This is largely because current vaccines are aimed at

Yersinia ruckeri Isolates Recovered from Diseased Atlantic Salmon (Salmo salar) in Scotland Are More Diverse than Those from Rainbow Trout (Oncorhynchus mykiss) and Represent Distinct Subpopulations.

PubMed

Ormsby, Michael J; Caws, Thomas; Burchmore, Richard; Wallis, Tim; Verner-Jeffreys, David W; Davies, Robert L

2016-10-01

Yersinia ruckeri is the etiological agent of enteric redmouth (ERM) disease of farmed salmonids. Enteric redmouth disease is traditionally associated with rainbow trout (Oncorhynchus mykiss, Walbaum), but its incidence in Atlantic salmon (Salmo salar) is increasing. Yersinia ruckeri isolates recovered from diseased Atlantic salmon have been poorly characterized, and very little is known about the relationship of the isolates associated with these two species. Phenotypic approaches were used to characterize 109 Y. ruckeri isolates recovered over a 14-year period from infected Atlantic salmon in Scotland; 26 isolates from infected rainbow trout were also characterized. Biotyping, serotyping, and comparison of outer membrane protein profiles identified 19 Y. ruckeri clones associated with Atlantic salmon but only five associated with rainbow trout; none of the Atlantic salmon clones occurred in rainbow trout and vice versa These findings suggest that distinct subpopulations of Y. ruckeri are associated with each species. A new O serotype (designated O8) was identified in 56 biotype 1 Atlantic salmon isolates and was the most common serotype identified from 2006 to 2011 and in 2014, suggesting an increased prevalence during the time period sampled. Rainbow trout isolates were represented almost exclusively by the same biotype 2, serotype O1 clone that has been responsible for the majority of ERM outbreaks in this species within the United Kingdom since the 1980s. However, the identification of two biotype 2, serotype O8 isolates in rainbow trout suggests that vaccines containing serotypes O1 and O8 should be evaluated in both rainbow trout and Atlantic salmon for application in Scotland. Vaccination plays an important role in protecting Atlantic salmon against the bacterial pathogen Yersinia ruckeri, but, in recent years, there has been an increasing incidence of vaccine breakdown in salmon. This is largely because current vaccines are aimed at rainbow trout and are

Yersinia infection tools-characterization of structure and function of adhesins.

PubMed

Mikula, Kornelia M; Kolodziejczyk, Robert; Goldman, Adrian

2012-01-01

Among the seventeen species of the Gram-negative genus Yersinia, three have been shown to be virulent and pathogenic to humans and animals-Y. enterocolitica, Y. pseudotuberculosis, and Y. pestis. In order to be so, they are armoured with various factors that help them adhere to tissues and organelles, cross the cellular barrier and escape the immune system during host invasion. The group of proteins that mediate pathogen-host interactions constitute adhesins. Invasin, Ail, YadA, YadB, YadC, Pla, and pH 6 antigen belong to the most prominent and best-known Yersinia adhesins. They act at different times and stages of infection complementing each other by their ability to bind a variety of host molecules such as collagen, fibronectin, laminin, β1 integrins, and complement regulators. All the proteins are anchored in the bacterial outer membrane (OM), often forming rod-like or fimbrial-like structures that protrude to the extracellular milieu. Structural studies have shown that the anchor region forms a β-barrel composed of 8, 10, or 12 antiparallel β-strands. Depending on the protein, the extracellular part can be composed of several domains belonging to the immunoglobulin fold superfamily, or form a coiled-coil structure with globular head domain at the end, or just constitute several loops connecting individual β-strands in the β-barrel. Those extracellular regions define the activity of each adhesin. This review focuses on the structure and function of these important molecules, and their role in pathogenesis.

Structure and regulation of the Yersinia pestis yscBCDEF operon.

PubMed Central

Haddix, P L; Straley, S C

1992-01-01

We have investigated the physical and genetic structure and regulation of the Yersinia pestis yscBCDEF region, previously called lcrC. DNA sequence analysis showed that this region is homologous to the corresponding part of the ysc locus of Yersinia enterocolitica and suggested that the yscBCDEF cistrons belong to a single operon on the low-calcium response virulence plasmid pCD1. Promoter activity measurements of ysc subclones indicated that yscBCDEF constitutes a suboperon of the larger ysc region by revealing promoter activity in a clone containing the 3' end of yscD, intact yscE and yscF, and part of yscG. These experiments also revealed an additional weak promoter upstream of yscD. Northern (RNA) analysis with a yscD probe showed that operon transcription is thermally induced and downregulated in the presence of Ca2+. Primer extension of operon transcripts suggested that two promoters, a moderate-level constitutive one and a stronger, calcium-downregulated one, control full-length operon transcription at 37 degrees C. Primer extension provided additional support for the proposed designation of a yscBCDEF suboperon by identifying a 5' end within yscF, for which relative abundances in the presence and absence of Ca2+ revealed regulation that is distinct from that for transcripts initiating farther upstream. YscB and YscC were expressed in Escherichia coli by using a high-level transcription system. Attempts to express YscD were only partially successful, but they revealed interesting regulation at the translational level. Images PMID:1624469

Yersinia infection tools—characterization of structure and function of adhesins

PubMed Central

Mikula, Kornelia M.; Kolodziejczyk, Robert; Goldman, Adrian

2013-01-01

Among the seventeen species of the Gram-negative genus Yersinia, three have been shown to be virulent and pathogenic to humans and animals—Y. enterocolitica, Y. pseudotuberculosis, and Y. pestis. In order to be so, they are armoured with various factors that help them adhere to tissues and organelles, cross the cellular barrier and escape the immune system during host invasion. The group of proteins that mediate pathogen–host interactions constitute adhesins. Invasin, Ail, YadA, YadB, YadC, Pla, and pH 6 antigen belong to the most prominent and best-known Yersinia adhesins. They act at different times and stages of infection complementing each other by their ability to bind a variety of host molecules such as collagen, fibronectin, laminin, β1 integrins, and complement regulators. All the proteins are anchored in the bacterial outer membrane (OM), often forming rod-like or fimbrial-like structures that protrude to the extracellular milieu. Structural studies have shown that the anchor region forms a β-barrel composed of 8, 10, or 12 antiparallel β-strands. Depending on the protein, the extracellular part can be composed of several domains belonging to the immunoglobulin fold superfamily, or form a coiled-coil structure with globular head domain at the end, or just constitute several loops connecting individual β-strands in the β-barrel. Those extracellular regions define the activity of each adhesin. This review focuses on the structure and function of these important molecules, and their role in pathogenesis. PMID:23316485

Behavior of Yersinian enteriocolitica in foods

USDA-ARS?s Scientific Manuscript database

Yersinia enterocolitica, a zoonotic pathogen that causes yersiniosis in humans and animals, is discussed. The prevalence in foods and infection of this pathogen to humans and animals was investigated, and most of the biochemical tests used to biogroup Y. enterocolitica stated. In this study, the pos...

[Isolation of pathogenic bacteria in pasteurized type C milk sold in Recife City, Pernambuco, Brazil].

PubMed

Padilha , M R; Fernandes , Z F; Leal, T C; Leal, N C; Almeida, A M

2001-01-01

In order to improve information about the microbiological quality of the milk commercially available in the city of Recife, 250 samples of pasteurized type-C milk and 50 samples of raw milk were analyzed for Yersinia enterocolitica and Listeria monocytogenes and verify the possible occurrence of Yersinia enterocolitica and Listeria monocytogenes. These bacteria can develop in refrigeration temperatures and are responsible for food-born diseases. Neither Y. enterocolitica nor L. monocytogenes were found in the samples analyzed. However, the presence of Y. intermedia and Y. frederiksenii was detected, these environmental species behave as opportunist pathogens. Through the methodology used for Listeria isolation, one isolate of Salmonella Montevideo was obtained from a sample of pasteurized milk and another isolated from one sample of raw milk. Besides these, several other bacteria species were found. It is likely that the large microbiota present in the samples and the procedures employed to destroy it could have hindered the isolation of Y. enterocolitica and L. monocytogenes.

Strategies for On-Line Decontamination of Carcasses

NASA Astrophysics Data System (ADS)

Byelashov, Oleksandr A.; Sofos, John N.

Microbial food safety has been one of the most important challenges for the meat industry during the last two decades due to important foodborne outbreaks traced to contaminated products and associated costly product recalls from the market. Escherichia coli O157:H7 and other non-O157 Shiga toxin-producing (STEC) strains, as well as Salmonella serotypes, Campylobacter jejuni, Clostridium perfringens, Clostridium botulinum, Listeria monocytogenes, Staphylococcus aureus, Yersinia enterocolitica, Aeromonas hydrophila, and Bacillus cereusare important pathogenic contaminants of meat and poultry products (Sofos, 2004a). STEC, especially, have been of major concern for the beef industry for a number of years, since for almost two decades contaminated beef products have been major sources of foodborne E. coli O157:H7 infection (Rangel, Sparling, Crowe, Griffin, & Swerdlow, 2005).

Monitoring of Foodborne Pathogens in Raw Cow Milk in Tuscany

PubMed Central

D’Alonzo, Alessia; Senese, Matteo; Fabbri, Ilaria; Cirri, Cristina; Milioni, Carla; Valenza, Valeria; Tolli, Rita; Campeis, Francesca; Fischetti, Roberto

2014-01-01

Raw milk consumption in Italy has increased over the last few years and although raw milk is characterised by cold chain, short shelf-life and the duty of boiling before domestic consumption, it is still considered a hazard. From 2010 to 2013 a monitoring survey of raw milk sold through vending machines was carried out to investigate the occurrence of several foodborne pathogens stipulated in the national legal requirements, i.e. Listeria monocytogenes, Campylobacter spp., Salmonella spp., Escherichia coli O:157 and coagulase-positive Staphylococci. A total of 127 raw milk samples were collected from 19 dairy herds in Tuscany Region, Italy. In addition, the milk samples were tested for the presence and count of Yersinia genus. Results shown that only one sample was positive for non verocytotoxin-producing E. coli O:157, whereas a total of 38 samples (29.9%) were postive for Yersinia genus; of the total 39 isolated bacteria, 23.6% were Y. enterocolitica, 2.4% Y. kristenseni and 4.7% Y. frederiksenii. None isolate was enteropathogenic; serotypes O:5 and O:8 were found in 16.6 and 13.3% of the isolates respectively, whereas none of the serotypes tested was detected in 70% of the isolates. The most probable number method revealed a count value between 0.03 and 24 MPN/mL. Based on these data a general assurance on health safety of raw milk produced and sold in Tuscany could be assessed. PMID:27800320

Yersinia YopP-induced apoptotic cell death in murine dendritic cells is partially independent from action of caspases and exhibits necrosis-like features.

PubMed

Gröbner, Sabine; Autenrieth, Stella E; Soldanova, Irena; Gunst, Dani S J; Schaller, Martin; Bohn, Erwin; Müller, Steffen; Leverkus, Martin; Wesselborg, Sebastian; Autenrieth, Ingo B; Borgmann, Stefan

2006-11-01

Yersinia outer protein P (YopP) is a virulence factor of Yersinia enterocolitica that is injected into the cytosol of host cells where it targets MAP kinase kinases (MKKs) and inhibitor of kappaB kinase (IKK)-beta resulting in inhibition of cytokine production as well as induction of apoptosis in murine macrophages and dendritic cells (DC). Here we show that DC death was only partially prevented by the broad spectrum caspase inhibitor zVAD-fmk, indicating simultaneous caspase-dependent and caspase-independent mechanisms of cell death induction by YopP. Microscopic analyses and measurement of cell size demonstrated necrosis-like morphology of caspase-independent cell death. Application of zVAD-fmk prevented cleavage of procaspases and Bid, decrease of the inner transmembrane mitochondrial potential DeltaPsi(m) and mitochondrial release of cytochrome c. From these data we conclude that YopP-induced activation of the mitochondrial death pathway is mediated upstream via caspases. In conclusion, our results suggest that YopP simultaneously induces caspase-dependent apoptotic and caspase-independent necrosis-like death in DC. However, it has to be resolved if necrosis-like DC death occurs independently from apoptotic events or as an apoptotic epiphenomenon.

Heat-killed Lactobacillus spp. cells enhance survivals of Caenorhabditis elegans against Salmonella and Yersinia infections.

PubMed

Lee, J; Choe, J; Kim, J; Oh, S; Park, S; Kim, S; Kim, Y

2015-12-01

This study examined the effect of feeding heat-killed Lactobacillus cells on the survival of Caenorhabditis elegans nematodes after Salmonella Typhimurium and Yersinia enterocolitica infection. The feeding of heat-killed Lactobacillus plantarum 133 (LP133) and Lactobacillus fermentum 21 (LP21) cells to nematodes was shown to significantly increase the survival rate as well as stimulate the expression of pmk-1 gene that key factor for C. elegans immunity upon infection compared with control nematodes that were only fed Escherichia coli OP50 (OP50) cells. These results suggest that heat-killed LP133 and LF21 cells exert preventive or protective effects against the Gram-negative bacteria Salm. Typhimurium and Y. enterocolitica. To better understand the mechanisms underlying the LF21-mediated and LP133-mediated protection against bacterial infection in nematodes, transcriptional profiling was performed for each experimental group. These experiments showed that genes related to energy generation and ageing, regulators of insulin/IGF-1-like signalling, DAF genes, oxidation and reduction processes, the defence response and/or the innate immune response, and neurological processes were upregulated in nematodes that had been fed heat-killed Lactobacillus cells compared with nematodes that had been fed E. coli cells. In this study, the feeding of heat-killed Lactobacillus bacteria to Caenorhabditis elegans nematodes was shown to decrease infection by Gram-negative bacteria and increase the host lifespan. C. elegans has a small, well-organized genome and is an excellent in vivo model organism; thus, these results will potentially shed light on important Lactobacillus-host interactions. © 2015 The Society for Applied Microbiology.

[Bilateral vestibular loss as a post-infection complication of yersiniosis?].

PubMed

Bücheler, M; Löwenheim, H

1997-08-01

Yersinia infections other than plaque are caused by Yersinia pseudotuberculosis and Yersinia enterocolitica. Food and water contamination as well as animal-to-person and person-to-person contact are common pathways of transmission. Clinical manifestations include enteritis, enterocolitis, acute appendicitis, inflammation of the terminal ileum, and mesenteric adenitis. Y. enterocolitica may cause bacteremia with subsequent septicemia predominantly in patients with underlying illnesses such as diabetes mellitus or malignancy. More frequently enteritis is followed by immunological post-infectious syndromes such as arthritis and erythema nodosum. The present case report discusses bilateral vestibular loss possibly caused by an infection with Y. enterocolitica. A 27-year-old caucasian woman initially presented with the otologic symptom of spinning vertigo accompanied by nausea and vomiting. Physical exam revealed spontaneous nystagmus to the left. Bithermal caloric responses were absent. Pure tone audiometry showed a bilateral symmetric high-frequency sensorineural hearing loss. Neurologic exams did not reveal involvement of the central vestibular system. Perilymphatic fistula on the left side was excluded by tympanoscopy. Serology for rheumatoid factors and HLA B27 was negative. Lead or mercury intoxication was also excluded. In her medical history the patient reported intermittent watery diarrhea and stress dependent arthralgia that had commenced during a stay in Argentina three years ago. Serology was positive, revealing elevated titers for Y. enterocolitica type 3 (1:200) and type 9 (1:400). Bilateral vestibular loss is rare. The main cause is aminoglycoside ototoxicity or meningitis. Yersina infections have not yet been described as inducing disease of the labyrinth. Present pathophysiologic knowledge of yersinia infections is described as follows: After peroral infection, gastrointestinal permeability is increased. Low-molecular-weight substances may enter the

Characterisation of a serotype O1 Yersinia ruckeri isolate from the Isle of Man: further evidence that O antigen serotype is not a reliable indicator of virulence

USDA-ARS?s Scientific Manuscript database

As part of a routine disease surveillance exercise, a culture of the Gram negative bacterial pathogen Yersinia ruckeri was obtained from one of 150 largely asymptomatic rainbow trout from a farm on the Isle of Man, an island off the North West coast of Great Britain. This is the first reported isol...

Yersinia pekkanenii sp. nov.

PubMed

Murros-Kontiainen, Anna; Johansson, Per; Niskanen, Taina; Fredriksson-Ahomaa, Maria; Korkeala, Hannu; Björkroth, Johanna

2011-10-01

The taxonomic position of three strains from water, soil and lettuce samples was studied by using a polyphasic taxonomic approach. The strains were reported to lack the virulence-encoding genes inv and virF in a previous study. Controversially, API 20 E and some other phenotypic tests suggested that the strains belong to Yersinia pseudotuberculosis, which prompted this polyphasic taxonomic study. In both the phylogenetic analyses of four housekeeping genes (glnA, gyrB, recA and HSP60) and numerical analyses of HindIII and EcoRI ribopatterns, the strains formed a separate group within the genus Yersinia. Analysis of the 16S rRNA gene sequences showed that the strains were related to Yersinia aldovae and Yersinia mollaretii, but DNA-DNA hybridization analysis differentiated them from these species. Based on the results of the phylogenetic and DNA-DNA hybridization analyses, a novel species, Yersinia pekkanenii sp. nov., is proposed. The type strain is ÅYV7.1KOH2(T) ( = DSM 22769(T)  = LMG 25369(T)).

Rare Infections: Yersinia Enterocolitica and Yersinia Pseudotuberculosis

MedlinePlus

... Life Family Life Family Life Medical Home Family Dynamics Media Work & Play Getting Involved in Your Community ... and Urinary Tract Glands & Growth Head Neck & Nervous System Heart Infections Learning Disabilities Obesity Orthopedic Prevention Sexually ...

LcrQ and SycH function together at the Ysc type III secretion system in Yersinia pestis to impose a hierarchy of secretion.

PubMed

Wulff-Strobel, Christine R; Williams, Andrew W; Straley, Susan C

2002-01-01

LcrQ is a regulatory protein unique to Yersinia. Previous study in Yersinia pseudotuberculosis and Yersinia enterocolitica prompted the model in which LcrQ negatively regulates the expression of a set of virulence proteins called Yops, and its secretion upon activation of the Yop secretion (Ysc) type III secretion system permits full induction of Yops expression. In this study, we tested the hypothesis that LcrQ's effects on Yops expression might be indirect. Excess LcrQ was found to exert an inhibitory effect specifically at the level of Yops secretion, independent of production, and a normal inner Ysc gate protein LcrG was required for this activity. However, overexpression of LcrQ did not prevent YopH secretion, suggesting that LcrQ's effects at the Ysc discriminate among the Yops. We tested this idea by determining the effects of deletion or overexpression of LcrQ, YopH and their common chaperone SycH on early Yop secretion through the Ysc. Together, our findings indicated that LcrQ is not a negative regulator directly, but it acts in partnership with SycH at the Ysc gate to control the entry of a set of Ysc secretion substrates. A hierarchy of YopH secretion before YopE appears to be imposed by SycH in conjunction with both LcrQ and YopH. LcrQ and SycH in addition influenced the deployment of LcrV, a component of the Yops delivery mechanism. Accordingly, LcrQ appears to be a central player in determining the substrate specificity of the Ysc.

A Case Control Study of Incident Rheumatological Conditions Following Acute Gastroenteritis During Military Deployment

DTIC Science & Technology

2013-01-01

commonly caused by diarrhoeagenic Escherichia coli, Campylobacter spp., Shigella spp. and non- typhoidal Salmonella spp., although viral and parasitic...and coli, non-typhoidal Salmonella spp, Shigella spp and Yersinia enterocolitica.9–13 Reports of ReA following bacterial gastroenteritis are most...significantly with age. In a prospective study of culture-confirmed Campylobacter, E coli O157, Salmonella, Shigella and Yersinia infections among

Pathogenicity of a strain of Yersinia pseudotuberculosis isolated from a pig with porcine colitis syndrome.

PubMed

Neef, N A; Lysons, R J

1994-07-16

A strain of Yersinia pseudotuberculosis (NCTC 12718), isolated from a seven-week-old pig suffering from an ulcerative typhlocolitis, was inoculated orally into 16 growing pigs in two separate experiments. At necropsy 10 days later, typhlocolitis was present in nine of the pigs, and it was accompanied by diarrhoea in four cases. In both the original case and in the experimental pigs, the typhlocolitis was characterised by microabscesses of the lamina propria, frequently involving ulceration or erosion of the surface epithelium. The organism was of serotype IIa, which has not been isolated previously from pigs in the United Kingdom. Y pseudotuberculosis may be the aetiological agent responsible in some cases of porcine colitis syndrome.

Differential detection of pathogenic Yersinia spp. by fluorescence in situ hybridization.

PubMed

Rohde, Alexander; Hammerl, Jens Andre; Appel, Bernd; Dieckmann, Ralf; Al Dahouk, Sascha

2017-04-01

Yersinia enterocolitica, Y. pseudotuberculosis and Y. pestis are pathogens of major medical importance, which are responsible for a considerable number of infections every year. The detection of these species still relies on cultural methods, which are slow, labour intensive and often hampered by the presence of high amounts of accompanying flora. In this study, fluorescence in situ hybridization (FISH) was used to develop a fast, sensitive and reliable alternative to detect viable bacteria in food. For this purpose, highly specific probes targeting the 16S and 23S ribosomal RNA were employed to differentially detect each of the three species. In order to enable the differentiation of single nucleotide polymorphisms (SNPs), suitable competitor oligonucleotides and locked nucleic acids (LNAs) were used. Starved cells still showed a strong signal and a direct viable count (DVC) approach combined with FISH optimized live/dead discrimination. Sensitivity of the FISH test was high and even a single cell per gram of spiked minced pork meat could be detected within a day, demonstrating the applicability to identify foodborne hazards at an early stage. In conclusion, the established FISH tests proved to be promising tools to compensate existing drawbacks of the conventional cultural detection of these important zoonotic agents. Copyright © 2016 Elsevier Ltd. All rights reserved.

Temperature sensing in Yersinia pestis: regulation of yopE transcription by lcrF.

PubMed Central

Hoe, N P; Minion, F C; Goguen, J D

1992-01-01

In Escherichia coli, a yopE::lacZ fusion was found to be regulated by temperature in the presence of the cloned BamHI G fragment of Yersinia pestis plasmid pCD1, which contains the lcrF locus. Increasing the copy number of lcrF relative to that of the yopE reporter had a negligible effect on the induction ratio (26 versus 37 degrees C) but caused large reductions in the absolute levels of yopE transcription. We localized the lcrF gene by monitoring the induction phenotype of BamHI G deletion derivatives. Sequencing revealed an open reading frame capable of encoding a protein of 30.8 kDa. A protein product of this size was detected in a T7 expression system, and LcrF-dependent yopE-specific DNA binding activity was observed. As expected, LcrF exhibited 98% homology to VirF of Yersinia enterocolitica and significant homology to the carboxy termini of other members of the AraC family of transcriptional regulatory proteins. These proteins could be divided into two classes according to function: those regulating operons involved in catabolism of carbon and energy sources and those involved in regulating virulence genes. lcrF::lacZ transcriptional fusions were constructed and analyzed in Y. pestis and E. coli. The activity of the fusions was not affected by the native pCD1 virulence plasmid, an intact lcrF gene, or temperature. Thus, induction of lcrF transcription is not essential for temperature-dependent activation of yopE transcription. A portion of LcrF was found associated with the membrane fraction in E. coli; however, pulse-chase experiments indicated that this result is an artifact of fractionation. Images PMID:1624422

Plasmid-determined cytotoxicity in Yersinia pestis and Yersinia pseudotuberculosis.

PubMed Central

Goguen, J D; Walker, W S; Hatch, T P; Yother, J

1986-01-01

Yersinia pestis KIM5 was found to be cytotoxic for the IC21 and P388D1 mouse macrophage cell lines, as well as for resident peritoneal macrophages from C57BL/6 mice. Affected cells phagocytosed KIM5 inefficiently, became spherical, detached readily from culture dishes, and retained 51Cr poorly. The cytotoxic effect was dependent on the presence of the 75-kilobase plasmid pCD1. Because this plasmid also encodes the low calcium response (LCR), three Mu d1 insertion mutants previously shown to be LCR- and of reduced virulence in mice were examined for cytotoxicity; all were found to be atoxic. The insertions in these mutants lie within three distinct LCR loci (lcrB, C, and D). Like LCR, cytotoxicity was expressed only at 37 degrees C. Unlike LCR, it was not influenced by Ca2+ concentration, indicating that the V and W antigens are probably not involved. Yersinia pseudotuberculosis was found to have a similar plasmid-dependent cytotoxicity. Thus, biological activity observed as cytotoxicity in vitro may well be a common feature contributing to virulence of the yersiniae. Images PMID:3949380

Immunology of Yersinia pestis Infection.

PubMed

Bi, Yujing

2016-01-01

As a pathogen of plague, Yersinia pestis caused three massive pandemics in history that killed hundreds of millions of people. Yersinia pestis is highly invasive, causing severe septicemia which, if untreated, is usually fatal to its host. To survive in the host and maintain a persistent infection, Yersinia pestis uses several stratagems to evade the innate and the adaptive immune responses. For example, infections with this organism are biphasic, involving an initial "noninflammatory" phase where bacterial replication occurs initially with little inflammation and following by extensive phagocyte influx, inflammatory cytokine production, and considerable tissue destruction, which is called "proinflammatory" phase. In contrast, the host also utilizes its immune system to eliminate the invading bacteria. Neutrophil and macrophage are the first defense against Yersinia pestis invading through phagocytosis and killing. Other innate immune cells also play different roles, such as dendritic cells which help to generate more T helper cells. After several days post infection, the adaptive immune response begins to provide organism-specific protection and has a long-lasting immunological memory. Thus, with the cooperation and collaboration of innate and acquired immunity, the bacterium may be eliminated from the host. The research of Yersinia pestis and host immune systems provides an important topic to understand pathogen-host interaction and consequently develop effective countermeasures.

Enteritis

MedlinePlus

... enteritis E coli enteritis Food poisoning Radiation enteritis Salmonella enteritis Shigella enteritis Staph aureus food poisoning Symptoms ... store food that needs to stay chilled. Images Salmonella typhi organism Yersinia enterocolitica organism Campylobacter jejuni organism ...

Serological and molecular investigation for brucellosis in swine in selected districts of Uganda.

PubMed

Erume, Joseph; Roesel, Kristina; Dione, Michel M; Ejobi, Francis; Mboowa, Gerald; Kungu, Joseph M; Akol, Joyce; Pezo, Danilo; El-Adawy, Hosny; Melzer, Falk; Elschner, Mandy; Neubauer, Heinrich; Grace, Delia

2016-08-01

Brucellosis is a notifiable zoonotic disease affecting livestock, humans, and wildlife in Uganda. Pigs can be infected with human pathogenic Brucella suis biovars 1 and 3 and can be a significant source of brucellosis for humans. Uganda has a rapidly growing pig population, and the pork consumption per capita is the highest in East Africa. The objective of this work was to determine the seroprevalence of brucellosis in Ugandan pigs. A cross-sectional serosurvey of pigs was conducted in three of the major pig-keeping districts in Uganda (Masaka (n = 381 samples), Mukono (n = 398), and Kamuli (n = 414)). In addition, pigs originating from these districts were sampled in the major pig abattoir in Kampala (n = 472). In total, 1665 serum samples were investigated by serological and molecular tests. Only three putative brucellosis-positive samples were detected serologically using indirect ELISA. These sera were found negative for Brucella antibodies by CFT; however, two had antibodies against Yersinia enterocolitica as determined by SAT. Presence of antibodies against Yersiniae was confirmed by Y. enterocolitica antibody-specific ELISA. The two Yersiniae ELISA-positive samples were brucellosis negative using real-time PCR. We tested additional 142 sera from the 1665 samples with real-time PCR. All tested negative. Under this type of production system, we expect a maximum B. suis prevalence of less than 1 % at 95 % confidence level, and therefore, the risk of acquiring brucellosis from the pigs or their products is negligible. However, pigs may harbor the zoonotic Y. enterocolitica. This is the first study to investigate the occurrence of brucellosis in pigs in Uganda and the first study to report Y. enterocolitica antibodies in swine in Uganda.

Free-Living Species of Carnivorous Mammals in Poland: Red Fox, Beech Marten, and Raccoon as a Potential Reservoir of Salmonella, Yersinia, Listeria spp. and Coagulase-Positive Staphylococcus.

PubMed

Nowakiewicz, Aneta; Zięba, Przemysław; Ziółkowska, Grażyna; Gnat, Sebastian; Muszyńska, Marta; Tomczuk, Krzysztof; Majer Dziedzic, Barbara; Ulbrych, Łukasz; Trościańczyk, Aleksandra

2016-01-01

The objective of the study was to examine a population of free-living carnivorous mammals most commonly found in Poland (red fox, beech marten, and raccoon) for the occurrence of bacteria that are potentially pathogenic for humans and other animal species and to determine their virulence potential (the presence of selected virulence genes). From the total pool of isolates obtained (n = 328), we selected 90 belonging to species that pose the greatest potential threat to human health: Salmonella spp. (n = 19; 4.51%), Yersinia enterocolitica (n = 10; 2.37%), Listeria monocytogenes and L. ivanovii (n = 21), and Staphylococcus aureus (n = 40; 9.5%). The Salmonella spp. isolates represented three different subspecies; S. enterica subsp. enterica accounted for a significant proportion (15/19), and most of the serotypes isolated (S. Typhimurium, S. Infantis, S. Newport and S. Enteritidis) were among the 10 non-typhoidal Salmonella serotypes that are most often responsible for infections in Europe, including Poland. Y. enterococlitica was detected in the smallest percentage of animals, but 60% of strains among the isolates tested possessed the ail gene, which is responsible for attachment and invasion. Potentially pathogenic Listeria species were isolated from approx. 5% of the animals. The presence of all tested virulence genes was shown in 35% of L. monocytogenes strains, while in the case of the other strains, the genes occurred in varying numbers and configurations. The presence of the inlA, inlC, hlyA, and iap genes was noted in all strains, whereas the genes encoding PI-PLC, actin, and internalin Imo2821 were present in varying percentages (from 80% to 55%). S. aureus was obtained from 40 individuals. Most isolates possessed the hla, hld (95% for each), and hlb (32.5%) genes encoding hemolysins as well as the gene encoding leukotoxin lukED (70%). In a similar percentage of strains (77.5%), the presence of at least one gene encoding enterotoxin was found, with 12

The importance of the magnesium transporter MgtB for virulence of Yersinia pseudotuberculosis and Yersinia pestis.

PubMed

Ford, Donna C; Joshua, George W P; Wren, Brendan W; Oyston, Petra C F

2014-12-01

Mg(2+) has been shown to be an important signal controlling gene regulation via the PhoPQ two-component regulatory system for a range of Gram-negative bacteria, including Yersinia pestis and Yersinia pseudotuberculosis. The magnesium ion transporter MgtB is part of the complex PhoPQ regulon, being upregulated in response to low Mg(2+). Despite the presence of other Mg(2+) transport systems in Yersinia, inactivation of mgtB had a significant effect on the ability of the bacteria to scavenge this crucial ion. Whereas inactivation of PhoPQ is reported to adversely affect intracellular survival, we show that Y. pestis and Y. pseudotuberculosis ΔmgtB mutants survived equally as well as the respective parent strain within macrophages, although they were more sensitive to killing in the Galleria model of infection. Surprisingly, despite MgtB being only one member of the Mg(2+) stimulon and PhoPQ controlling the expression levels of a range of genes including mgtB, the Yersinia ΔmgtB mutants were more highly attenuated than the equivalent Yersinia ΔphoP mutants in mouse models of infection. MgtB may be a suitable target for development of novel antimicrobials, and investigation of its role may help elucidate the contribution of this component of the PhoPQ regulon to pathogenesis. © 2014 British Crown Copyright 2014/DSTL.

Characterization of Chinese Haemophilus parasuis Isolates by Traditional Serotyping and Molecular Serotyping Methods

PubMed Central

Ma, Lina; Wang, Liyan; Chu, Yuefeng; Li, Xuerui; Cui, Yujun; Chen, Shengli; Zhou, Jianhua; Li, Chunling; Lu, Zhongxin; Liu, Jixing; Liu, Yongsheng

2016-01-01

Haemophilus parasuis is classified mainly through serotyping, but traditional serotyping always yields non-typable (NT) strains and unreliable results via cross-reactions. Here, we surveyed the serotype prevalence of Chinese H. parasuis isolates using traditional serotyping (gel immuno-diffusion test, GID) and molecular serotyping (multiplex PCR, mPCR). We also investigated why discrepant results between these methods were obtained, and investigated mPCR failure through whole-genome sequencing. Of the 100 isolate tested, 73 (73%) and 93 (93%) were serotyped by the GID test and mPCR, respectively, with a concordance rate of 66% (66/100). Additionally, mPCR reduced the number of NT isolates from 27 (27%) for the GID testing, to seven (7%). Eleven isolates were sequenced, including nine serotype-discrepant isolates from mPCR and GID typing (excluding strains that were NT by GID only) and two NT isolates from both methods, and their in silico serotypes were obtained from genome sequencing based on their capsule loci. The mPCR results were supported by the in silico serotyping of the seven serotype-discrepant isolates. The discrepant results and NT isolates determined by mPCR were attributed to deletions and unknown sequences in the serotype-specific region of each capsule locus. Compared with previous investigations, this study found a similar predominant serotype profile, but a different prevalence frequency for H. parasuis, and the five most prevalent serotypes or strain groups were serotypes 5, 4, NT, 7 and 13 for mPCR, and serotypes 5, NT, 4, 7 and 13/10/14 for GID. Additionally, serotype 7 was recognized as a principal serotype in this work. PMID:28005999

Discordance in the effects of Yersinia pestis on the dendritic cell functions manifested by induction of maturation and paralysis of migration.

PubMed

Velan, Baruch; Bar-Haim, Erez; Zauberman, Ayelet; Mamroud, Emanuelle; Shafferman, Avigdor; Cohen, Sara

2006-11-01

The encounter between invading microorganisms and dendritic cells (DC) triggers a series of events which include uptake and degradation of the microorganism, induction of a maturation process, and enhancement of DC migration to the draining lymph nodes. Various pathogens have developed strategies to counteract these events as a measure to evade the host defense. In the present study we found that interaction of the Yersinia pestis EV76 strain with DC has no effect on cell viability and is characterized by compliance with effective maturation, which is manifested by surface display of major histocompatibility complex class II, of costimulatory markers, and of the chemokine receptor CCR7. This is in contrast to maturation inhibition and cell death induction exerted by the related species Yersinia enterocolitica WA O:8. Y. pestis interactions with DC were found, however, to impair functions related to cytoskeleton rearrangement. DC pulsed with Y. pestis failed to adhere to solid surfaces and to migrate toward the chemokine CCL19 in an in vitro transmembrane assay. Both effects were dependent on the presence of the pCD1 virulence plasmid and on a bacterial growth shift to 37 degrees C prior to infection. Moreover, while instillation of a pCD1-cured Y. pestis strain into mouse airways triggered effective transport of alveolar DC to the mediastinal lymph node, instillation of Y. pestis harboring the plasmid failed to do so. Taken together, these results suggest that virulence plasmid-dependent impairment of DC migration is the major mechanism utilized by Y. pestis to subvert DC function.

Novel plasmids and resistance phenotypes in Yersinia pestis: unique plasmid inventory of strain Java 9 mediates high levels of arsenic resistance.

PubMed

Eppinger, Mark; Radnedge, Lyndsay; Andersen, Gary; Vietri, Nicholas; Severson, Grant; Mou, Sherry; Ravel, Jacques; Worsham, Patricia L

2012-01-01

Growing evidence suggests that the plasmid repertoire of Yersinia pestis is not restricted to the three classical virulence plasmids. The Java 9 strain of Y. pestis is a biovar Orientalis isolate obtained from a rat in Indonesia. Although it lacks the Y. pestis-specific plasmid pMT, which encodes the F1 capsule, it retains virulence in mouse and non-human primate animal models. While comparing diverse Y. pestis strains using subtractive hybridization, we identified sequences in Java 9 that were homologous to a Y. enterocolitica strain carrying the transposon Tn2502, which is known to encode arsenic resistance. Here we demonstrate that Java 9 exhibits high levels of arsenic and arsenite resistance mediated by a novel promiscuous class II transposon, named Tn2503. Arsenic resistance was self-transmissible from Java 9 to other Y. pestis strains via conjugation. Genomic analysis of the atypical plasmid inventory of Java 9 identified pCD and pPCP plasmids of atypical size and two previously uncharacterized cryptic plasmids. Unlike the Tn2502-mediated arsenic resistance encoded on the Y. enterocolitica virulence plasmid; the resistance loci in Java 9 are found on all four indigenous plasmids, including the two novel cryptic plasmids. This unique mobilome introduces more than 105 genes into the species gene pool. The majority of these are encoded by the two entirely novel self-transmissible plasmids, which show partial homology and synteny to other enterics. In contrast to the reductive evolution in Y. pestis, this study underlines the major impact of a dynamic mobilome and lateral acquisition in the genome evolution of the plague bacterium.

Novel Plasmids and Resistance Phenotypes in Yersinia pestis: Unique Plasmid Inventory of Strain Java 9 Mediates High Levels of Arsenic Resistance

PubMed Central

Eppinger, Mark; Radnedge, Lyndsay; Andersen, Gary; Vietri, Nicholas; Severson, Grant; Mou, Sherry; Ravel, Jacques; Worsham, Patricia L.

2012-01-01

Growing evidence suggests that the plasmid repertoire of Yersinia pestis is not restricted to the three classical virulence plasmids. The Java 9 strain of Y. pestis is a biovar Orientalis isolate obtained from a rat in Indonesia. Although it lacks the Y. pestis-specific plasmid pMT, which encodes the F1 capsule, it retains virulence in mouse and non-human primate animal models. While comparing diverse Y. pestis strains using subtractive hybridization, we identified sequences in Java 9 that were homologous to a Y. enterocolitica strain carrying the transposon Tn2502, which is known to encode arsenic resistance. Here we demonstrate that Java 9 exhibits high levels of arsenic and arsenite resistance mediated by a novel promiscuous class II transposon, named Tn2503. Arsenic resistance was self-transmissible from Java 9 to other Y. pestis strains via conjugation. Genomic analysis of the atypical plasmid inventory of Java 9 identified pCD and pPCP plasmids of atypical size and two previously uncharacterized cryptic plasmids. Unlike the Tn2502-mediated arsenic resistance encoded on the Y. enterocolitica virulence plasmid; the resistance loci in Java 9 are found on all four indigenous plasmids, including the two novel cryptic plasmids. This unique mobilome introduces more than 105 genes into the species gene pool. The majority of these are encoded by the two entirely novel self-transmissible plasmids, which show partial homology and synteny to other enterics. In contrast to the reductive evolution in Y. pestis, this study underlines the major impact of a dynamic mobilome and lateral acquisition in the genome evolution of the plague bacterium. PMID:22479347

A serotype-specific polymerase chain reaction for identification of Pasteurella multocida serotype 1

USGS Publications Warehouse

Rocke, Tonie E.; Smith, Susan R.; Miyamoto, Amy; Shadduck, Daniel J.

2002-01-01

A serotype-specific polymerase chain reaction (PCR) assay was developed for detection and identification of Pasteurella multocida serotype 1, the causative agent of avian cholera in wild waterfowl. Arbitrarily primed PCR was used to detect DNA fragments that distinguish serotype 1 from the other 15 serotypes of P. multocida (with the exception of serotype 14). Oligonucleotide primers were constructed from these sequences, and a PCR assay was optimized and evaluated. PCR reactions consistently resulted in amplification products with reference strains 1 and 14 and all other serotype 1 strains tested, with cell numbers as low as 2.3 cells/ml. No amplification products were produced with other P. multocida serotypes or any other bacterial species tested. To compare the sensitivity and further test the specificity of this PCR assay with traditional culturing and serotyping techniques, tissue samples from 84 Pekin ducks inoculated with field strains of P. multocida and 54 wild lesser snow geese collected during an avian cholera outbreak were provided by other investigators working on avian cholera. PCR was as sensitive (58/64) as routine isolation (52/64) in detecting and identifying P. multocida serotype 1 from the livers of inoculated Pekins that became sick or died from avian cholera. No product was amplified from tissues of 20 other Pekin ducks that received serotypes other than type 1 (serotype 3, 12 × 3, or 10) or 12 control birds. Of the 54 snow geese necropsied and tested for P. multocida, our PCR detected and identified the bacteria from 44 compared with 45 by direct isolation. The serotype-specific PCR we developed was much faster and less labor intensive than traditional culturing and serotyping procedures and could result in diagnosis of serotype 1 pasteurellosis within 24 hr of specimen submission.

A serotype-specific polymerase chain reaction for identification of Pasteurella multocida serotype 1

USGS Publications Warehouse

Rocke, T.E.; Smith, S.R.; Miyamoto, A.; Shadduck, D.J.

2002-01-01

A serotype-specific polymerase chain reaction (PCR) assay was developed for detection and identification of Pasteurella multocida serotype 1, the causative agent of avian cholera in wild waterfowl. Arbitrarily primed PCR was used to detect DNA fragments that distinguish serotype 1 from the other 15 serotypes of P. multocida (with the exception of serotype 14). Oligonucleotide primers were constructed from these sequences, and a PCR assay was optimized and evaluated. PCR reactions consistently resulted in amplification products with reference strains 1 and 14 and all other serotype 1 strains tested, with cell numbers as low as 2.3 cells/ml. No amplification products were produced with other P. multocida serotypes or any other bacterial species tested. To compare the sensitivity and further test the specificity of this PCR assay with traditional culturing and serotyping techniques, tissue samples from 84 Pekin ducks inoculated with field strains of P. multocida and 54 wild lesser snow geese collected during an avian cholera outbreak were provided by other investigators working on avian cholera. PCR was as sensitive (58/64) as routine isolation (52/64) in detecting and identifying P. multocida serotype 1 from the livers of inoculated Pekins that became sick or died from avian cholera. No product was amplified from tissues of 20 other Pekin ducks that received serotypes other than type 1 (serotype 3, 12 × 3, or 10) or 12 control birds. Of the 54 snow geese necropsied and tested for P. multocida, our PCR detected and identified the bacteria from 44 compared with 45 by direct isolation. The serotype-specific PCR we developed was much faster and less labor intensive than traditional culturing and serotyping procedures and could result in diagnosis of serotype 1 pasteurellosis within 24 hr of specimen submission.

Neutralization of Yersinia pestis-mediated macrophage cytotoxicity by anti-LcrV antibodies and its correlation with protective immunity in a mouse model of bubonic plague.

PubMed

Zauberman, Ayelet; Cohen, Sara; Levy, Yinon; Halperin, Gideon; Lazar, Shirley; Velan, Baruch; Shafferman, Avigdor; Flashner, Yehuda; Mamroud, Emanuelle

2008-03-20

Plague is a life-threatening disease caused by Yersinia pestis, for which effective-licensed vaccines and reliable predictors of in vivo immunity are lacking. V antigen (LcrV) is a major Y. pestis virulence factor that mediates translocation of the cytotoxic Yersinia protein effectors (Yops). It is a well-established protective antigen and a part of currently tested plague subunit vaccines. We have developed a highly sensitive in vitro macrophage cytotoxicity neutralization assay which is mediated by anti-LcrV antibodies; and studied the potential use of these neutralizing antibodies as an in vitro correlate of plague immunity in mice. The assay is based on a Y. pestis strain with enhanced cytotoxicity to macrophages in which endogenous yopJ was replaced by the more effectively translocated yopP of Y. enterocolitica O:8. Mice passively immunized with rabbit anti-LcrV IgG or actively immunized with recombinant LcrV were protected against lethal doses of a virulent Y. pestis strain, in a mouse model of bubonic plague. This protection significantly correlated with the in vitro neutralizing activity of the antisera but not with their corresponding ELISA titers. In actively immunized mice, a cutoff value for serum neutralizing activity, above which survival was assured with high degree of confidence, could be established for different vaccination regimes. The impact of overall findings on the potential use of serum neutralizing activity as a correlate of protective immunity is discussed.

Examination of Salmonella and Escherichia coli translocation from hog manure to forage, soil, and cattle grazed on the hog manure-treated pasture.

PubMed

Holley, Richard; Walkty, Joël; Blank, Gregory; Tenuta, Mario; Ominski, Kimberly; Krause, Denis; Ng, Lai-King

2008-01-01

Use of hog (Sus scrofa) manure as a fertilizer is a practical solution for waste re-utilization, however, it may serve as a vehicle for environmental and domestic animal contamination. Work was conducted to determine whether pathogens, naturally present in hog manure could be detected in cattle (Bos taurus) grazed on the manure-treated pasture, and whether forage contamination occurred. During two 3 mo summer trials manure was applied to yield < or = 124 kg available N per hectare in a single spring or split spring and fall application. Samples of hog manure, forage, soil, and cattle feces were analyzed for naturally occurring Salmonella, Yersinia enterocolitica, and Escherichia coli. To follow movement of Salmonella in the environment isolates were identified to serovar and serotyped. Transfer of E. coli from hog manure to soil and cattle was examined by randomly amplified polymorphic DNA (RAPD) analysis of >600 E. coli isolates. While Y. enterocolitica was absent from all samples, in both years S. enterica Derby and S. enterica Krefeld were found in most hog manure samples, but were only on forage samples in the second year. Salmonella enterica Typhimurium, absent from hog manure was present on some forage in the first year. Cattle feces and soil samples were consistently Salmonella negative. These contaminations could not be traced to manure application. During this study, Salmonella and E. coli found in hog manure had different RAPD genomic profiles from those found in the feces of cattle grazing on manure-treated pasture.

Serological and molecular heterogeneity among Yersinia ruckeri strains isolated from farmed Atlantic salmon Salmo salar in Chile.

PubMed

Bastardo, A; Bohle, H; Ravelo, C; Toranzo, A E; Romalde, J L

2011-02-22

We investigated 11 strains of Yersinia ruckeri, the causative agent of enteric redmouth disease (ERM), that had been isolated from Atlantic salmon Salmo salar L. farmed in Chile and previously vaccinated against ERM. Phylogenetic analysis of the 16S rRNA gene sequences confirmed the identification of the salmon isolates as Y. ruckeri. A comparative analysis of the biochemical characteristics was made by means of traditional and commercial miniaturised methods. All studied isolates were motile and Tween 80 positive, and were identified as biotype 1. In addition, drug susceptibility tests determined high sensitivity to sulphamethoxazole/trimethroprim, oxytetracycline, ampicillin and enrofloxacin in all isolates. Serological assays showed the presence of O1a, O1b and O2b serotypes, with a predominance of the O1b serotype in 9 strains. Analysis of the lipopolysaccharide profiles and the correspondent immunoblot confirmed these results. Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) of the outer membrane proteins revealed that all Chilean strains had profiles with a molecular weight range between 34 and 55 kDa, with 3 distinct groups based on differences in the major bands. Genotyping analyses by enterobacterial repetitive intergenic consensus (ERIC-) and repetitive extragenic palindromic (REP-)PCR techniques clearly indicated intraspecific genetic diversity among Chilean Y. ruckeri strains.

Reduced contamination of pig carcasses using an alternative pluck set removal procedure during slaughter.

PubMed

Biasino, W; De Zutter, L; Woollard, J; Mattheus, W; Bertrand, S; Uyttendaele, M; Van Damme, I

2018-05-26

This study compared the current pig slaughter procedure where the pluck set is completely removed with a procedure where the pluck set is partially removed, leaving the highly contaminated oral cavity, tonsils and tongue untouched. The effect on carcass contamination was investigated by enumerating hygiene indicator bacteria (total aerobic count, Enterobacteriaceae and E. coli) and cefotaxime-resistant E. coli (CREC) as well as assessing Salmonella and Yersinia enterocolitica presence on the sternum, elbow and throat of pig carcasses. Using the alternative pluck set removal, significantly lower mean numbers of hygiene indicator bacteria on throat samples and E. coli on elbow samples were found. Less pig carcasses were highly contaminated and a lower presence and level of CREC was observed. No difference in Salmonella or Yersinia enterocolitica presence was seen. The data in this study can help to assess the effect of this alternative procedure on the safety of pork and subsequently public health. Copyright © 2018 Elsevier Ltd. All rights reserved.

Yersinia pestis and Yersinia pseudotuberculosis infection: a regulatory RNA perspective

PubMed Central

Martínez-Chavarría, Luary C.; Vadyvaloo, Viveka

2015-01-01

Yersinia pestis, responsible for causing fulminant plague, has evolved clonally from the enteric pathogen, Y. pseudotuberculosis, which in contrast, causes a relatively benign enteric illness. An ~97% nucleotide identity over 75% of their shared protein coding genes is maintained between these two pathogens, leaving much conjecture regarding the molecular determinants responsible for producing these vastly different disease etiologies, host preferences and transmission routes. One idea is that coordinated production of distinct factors required for host adaptation and virulence in response to specific environmental cues could contribute to the distinct pathogenicity distinguishing these two species. Small non-coding RNAs that direct posttranscriptional regulation have recently been identified as key molecules that may provide such timeous expression of appropriate disease enabling factors. Here the burgeoning field of small non-coding regulatory RNAs in Yersinia pathogenesis is reviewed from the viewpoint of adaptive colonization, virulence and divergent evolution of these pathogens. PMID:26441890

Studies of the biosynthesis of 3,6-dideoxyhexoses: molecular cloning and characterization of the asc (ascarylose) region from Yersinia pseudotuberculosis serogroup VA.

PubMed Central

Thorson, J S; Lo, S F; Ploux, O; He, X; Liu, H W

1994-01-01

The 3,6-dideoxyhexoses are found in the lipopolysaccharides of gram-negative bacteria, where they have been shown to be the dominant antigenic determinants. Of the five 3,6-dideoxyhexoses known to occur naturally, four have been found in various strains of Salmonella enterica (abequose, tyvelose, paratose, and colitose) and all five, including ascarylose, are present among the serotypes of Yersinia pseudotuberculosis. Although there exists one report of the cloning of the rfb region harboring the abequose biosynthetic genes from Y. pseudotuberculosis serogroup HA, the detailed genetic principles underlying a 3,6-dideoxyhexose polymorphism in Y. pseudotuberculosis have not been addressed. To extend the available information on the genes responsible for 3,6-dideoxyhexose formation in Yersinia spp. and facilitate a comparison with the established rfb (O antigen) cluster of Salmonella spp., we report the production of three overlapping clones containing the entire gene cluster required for CDP-ascarylose biosynthesis. On the basis of a detailed sequence analysis, the implications regarding 3,6-dideoxyhexose polymorphism among Salmonella and Yersinia spp. are discussed. In addition, the functional cloning of this region has allowed the expression of Ep (alpha-D-glucose cytidylyltransferase), Eod (CDP-D-glucose 4,6-dehydratase), E1 (CDP-6-deoxy-L-threo-D-glycero-4- hexulose-3-dehydrase), E3 (CDP-6-deoxy-delta 3,4-glucoseen reductase), Eep (CDP-3,6-dideoxy-D-glycero-D- glycero-4-hexulose-5-epimerase), and Ered (CDP-3,6-dideoxy-L-glycero-D-glycero-4-hexulose-4-reductase), facilitating future mechanistic studies of this intriguing biosynthetic pathway. Images PMID:8071227

Yersinia ruckeri sp. nov., the redmouth (RM) bacterium

USGS Publications Warehouse

Ewing, W.H.; Ross, A.J.; Brenner, Don J.; Fanning, G. R.

1978-01-01

Cultures of the redmouth (RM) bacterium, one of the etiological agents of redmouth disease in rainbow trout (Salmo gairdneri) and certain other fishes, were characterized by means of their biochemical reactions, by deoxyribonucleic acid (DNA) hybridization, and by determination of guanine-plus-cytosine (G+C) ratios in DNA. The DNA relatedness studies confirmed the fact that the RM bacteria are members of the family Enterobacteriaceae and that they comprise a single species that is not closely related to any other species of Enterobacteriaceae. They are about 30% related to species of both Serratia and Yersinia. A comparison of the biochemical reactions of RM bacteria and serratiae indicated that there are many differences between these organisms and that biochemically the RM bacteria are most closely related to yersiniae. The G+C ratios of RM bacteria were approximated to be between 47.5 and 48.5% These values are similar to those of yersiniae but markedly different from those of serratiae. On the basis of their biochemical reactions and their G+C ratios, the RM bacteria are considered to be a new species of Yersinia, for which the name Yersinia ruckeri is proposed. Strain 2396-61 (= ATCC 29473) is designated the type strain of the species.

Chronic Lyme Disease and Co-infections: Differential Diagnosis

PubMed Central

Berghoff, Walter

2012-01-01

In Lyme disease concurrent infections frequently occur. The clinical and pathological impact of co-infections was first recognized in the 1990th, i.e. approximately ten years after the discovery of Lyme disease. Their pathological synergism can exacerbate Lyme disease or induce similar disease manifestations. Co-infecting agents can be transmitted together with Borrelia burgdorferi by tick bite resulting in multiple infections but a fraction of co-infections occur independently of tick bite. Clinically relevant co-infections are caused by Bartonella species, Yersinia enterocolitica, Chlamydophila pneumoniae, Chlamydia trachomatis, and Mycoplasma pneumoniae. In contrast to the USA, human granulocytic anaplasmosis (HGA) and babesiosis are not of major importance in Europe. Infections caused by these pathogens in patients not infected by Borrelia burgdorferi can result in clinical symptoms similar to those occurring in Lyme disease. This applies particularly to infections caused by Bartonella henselae, Yersinia enterocolitica, and Mycoplasma pneumoniae. Chlamydia trachomatis primarily causes polyarthritis. Chlamydophila pneumoniae not only causes arthritis but also affects the nervous system and the heart, which renders the differential diagnosis difficult. The diagnosis is even more complex when co-infections occur in association with Lyme disease. Treatment recommendations are based on individual expert opinions. In antibiotic therapy, the use of third generation cephalosporins should only be considered in cases of Lyme disease. The same applies to carbapenems, which however are used occasionally in infections caused by Yersinia enterocolitica. For the remaining infections predominantly tetracyclines and macrolides are used. Quinolones are for alternative treatment, particularly gemifloxacin. For Bartonella henselae, Chlamydia trachomatis, and Chlamydophila pneumoniae the combination with rifampicin is recommended. Erythromycin is the drug of choice for

Evaluation of cross-protection of bluetongue virus serotype 4 with other serotypes in sheep.

PubMed

Zulu, Gcwalisile B; Venter, Estelle H

2014-10-16

Bluetongue (BT) is a non-contagious disease of sheep and other domestic and wild ruminants caused by the bluetongue virus (BTV). Currently 26 serotypes of the virus have been identified. In South Africa, 22 serotypes have been identified and BT is controlled mainly by annual vaccinations using a freeze-dried live attenuated polyvalent BTV vaccine. The vaccine is constituted of 15 BTV serotypes divided into three separate bottles and the aim is to develop a vaccine using fewer serotypes without compromising the immunity against the disease. This study is based on previously reported cross-neutralisation of specific BTV serotypes in in vitro studies. Bluetongue virus serotype 4 was selected for this trial and was tested for cross-protection against serotype 4 (control), 1 (unrelated serotype), 9, 10 and 11 in sheep using the serum neutralisation test. The purpose of the study was to determine possible cross-protection of different serotypes in sheep. Of those vaccinated with BTV-4 and challenged with BTV-1, which is not directly related to BTV-4, 20% were completely protected and 80% showed clinical signs, but the reaction was not as severe as amongst the unvaccinated animals. In the group challenged with BTV-10, some showed good protection and some became very sick. Those challenged with BTV-9 and BTV-11 had good protection. The results showed that BTV-4 does not only elicit a specific immune response but can also protect against other serotypes.

Yersinia pestis endowed with increased cytotoxicity is avirulent in a bubonic plague model and induces rapid protection against pneumonic plague.

PubMed

Zauberman, Ayelet; Tidhar, Avital; Levy, Yinon; Bar-Haim, Erez; Halperin, Gideon; Flashner, Yehuda; Cohen, Sara; Shafferman, Avigdor; Mamroud, Emanuelle

2009-06-16

An important virulence strategy evolved by bacterial pathogens to overcome host defenses is the modulation of host cell death. Previous observations have indicated that Yersinia pestis, the causative agent of plague disease, exhibits restricted capacity to induce cell death in macrophages due to ineffective translocation of the type III secretion effector YopJ, as opposed to the readily translocated YopP, the YopJ homologue of the enteropathogen Yersinia enterocolitica Oratio8. This led us to suggest that reduced cytotoxic potency may allow pathogen propagation within a shielded niche, leading to increased virulence. To test the relationship between cytotoxic potential and virulence, we replaced Y. pestis YopJ with YopP. The YopP-expressing Y. pestis strain exhibited high cytotoxic activity against macrophages in vitro. Following subcutaneous infection, this strain had reduced ability to colonize internal organs, was unable to induce septicemia and exhibited at least a 10(7)-fold reduction in virulence. Yet, upon intravenous or intranasal infection, it was still as virulent as the wild-type strain. The subcutaneous administration of the cytotoxic Y. pestis strain appears to activate a rapid and potent systemic, CTL-independent, immunoprotective response, allowing the organism to overcome simultaneous coinfection with 10,000 LD(50) of virulent Y. pestis. Moreover, three days after subcutaneous administration of this strain, animals were also protected against septicemic or primary pneumonic plague. Our findings indicate that an inverse relationship exists between the cytotoxic potential of Y. pestis and its virulence following subcutaneous infection. This appears to be associated with the ability of the engineered cytotoxic Y. pestis strain to induce very rapid, effective and long-lasting protection against bubonic and pneumonic plague. These observations have novel implications for the development of vaccines/therapies against Y. pestis and shed new light on the

Yersinia vs. host Immunity: how a pathogen evades or triggers a protective response

PubMed Central

Chung, Lawton K.; Bliska, James B.

2015-01-01

The human pathogenic Yersinia species cause diseases that represent a significant source of morbidity and mortality. Despite this, specific mechanisms underlying Yersinia pathogenesis and protective host responses remain poorly understood. Recent studies have shown that Yersinia disrupt cell death pathways, perturb inflammatory processes and exploit immune cells to promote disease. The ensuing host responses following Yersinia infection include coordination of innate and adaptive immune responses in an attempt to control bacterial replication. Here, we highlight current advances in our understanding of the interactions between the pathogenic yersiniae and host cells, as well as the protective host responses mobilized to counteract these pathogens. Together, these studies enhance our understanding of Yersinia pathogenesis and highlight the ongoing battle between host and microbe. PMID:26638030

Insights into the evolution of Yersinia pestis through whole-genome comparison with Yersinia pseudotuberculosis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chain, Patrick S. G.; Carniel, E.; Larimer, Frank W

2004-09-01

Yersinia pestis, the causative agent of plague, is a highly uniform clone that diverged recently from the enteric pathogen Yersinia pseudotuberculosis. Despite their close genetic relationship, they differ radically in their pathogenicity and transmission. Here, we report the complete genomic sequence of Y. pseudotuberculosis IP32953 and its use for detailed genome comparisons with available Y. pestis sequences. Analyses of identified differences across a panel of Yersinia isolates from around the world reveal 32 Y. pestis chromosomal genes that, together with the two Y. pestis-specific plasmids, to our knowledge, represent the only new genetic material in Y. pestis acquired since themore » the divergence from Y. pseudotuberculosis. In contrast, 149 other pseudogenes (doubling the previous estimate) and 317 genes absent from Y. pestis were detected, indicating that as many as 13% of Y. pseudotuberculosis genes no longer function in Y. pestis. Extensive insertion sequence-mediated genome rearrangements and reductive evolution through massive gene loss, resulting in elimination and modification of preexisting gene expression pathways, appear to be more important than acquisition of genes in the evolution of Y. pestis. These results provide a sobering example of how a highly virulent epidemic clone can suddenly emerge from a less virulent, closely related progenitor.« less

Yersinia versus host immunity: how a pathogen evades or triggers a protective response.

PubMed

Chung, Lawton K; Bliska, James B

2016-02-01

The human pathogenic Yersinia species cause diseases that represent a significant source of morbidity and mortality. Despite this, specific mechanisms underlying Yersinia pathogenesis and protective host responses remain poorly understood. Recent studies have shown that Yersinia disrupt cell death pathways, perturb inflammatory processes and exploit immune cells to promote disease. The ensuing host responses following Yersinia infection include coordination of innate and adaptive immune responses in an attempt to control bacterial replication. Here, we highlight current advances in our understanding of the interactions between the pathogenic yersiniae and host cells, as well as the protective host responses mobilized to counteract these pathogens. Together, these studies enhance our understanding of Yersinia pathogenesis and highlight the ongoing battle between host and microbe. Copyright © 2015 Elsevier Ltd. All rights reserved.

Environmental Regulation of Yersinia Pathophysiology

PubMed Central

Chen, Shiyun; Thompson, Karl M.; Francis, Matthew S.

2016-01-01

Hallmarks of Yersinia pathogenesis include the ability to form biofilms on surfaces, the ability to establish close contact with eukaryotic target cells and the ability to hijack eukaryotic cell signaling and take over control of strategic cellular processes. Many of these virulence traits are already well-described. However, of equal importance is knowledge of both confined and global regulatory networks that collaborate together to dictate spatial and temporal control of virulence gene expression. This review has the purpose to incorporate historical observations with new discoveries to provide molecular insight into how some of these regulatory mechanisms respond rapidly to environmental flux to govern tight control of virulence gene expression by pathogenic Yersinia. PMID:26973818

[Comparison of efficacy of tests for differentiation of typical and atypical strains of Yersinia pestis and Yersinia pseudotuberculosis].

PubMed

Arsen'eva, T E; Lebedeva, S A; Trukhachev, A L; Vasil'eva, E A; Ivanova, V S; Bozhko, N V

2010-01-01

To characterize species specificity of officially recommended tests for differentiation of Yersiniapestis and Yersinia pseudotuberculosis and propose additional tests allowing for more accurate identification. Natural, laboratory and typical strains oftwo Yersinia species were studied using microbiological, molecular and biochemical methods. For PCR species-specific primers complementary to certain fragments of chromosomal DNA of each species as well as to several plasmid genes of Y. pestis were used. It was shown that such attributes of Y. pestis as form of colonies, fermentation ofrhamnose, melibiose and urea, susceptibility to diagnostic phages, nutritional requirements could be lost in pestis bacterial species or detected in pseudotuberculosis species. Such attribute as mobility as well as positive result of CoA-reaction on fraction V antigen are more reliable. Guaranteed differentiation of typical and changed according to differential tests strains is provided only by PCR-analysis with primers vlml2for/ISrev216 and JS respectively, which are homologous to certain chromosome fragments of one of two Yersinia species.

Seroepidemiological survey of pathogenic Yersinia in breeding squirrel monkeys in Japan.

PubMed

Iwata, Taketoshi; Une, Yumi; Lee, Ken-ichi; Nakamura, Shin-ichi; Taniguchi, Takahide; Hayashidani, Hideki

2010-08-01

To investigate the prevalence of antibodies to pathogenic Yersinia in breeding squirrel monkeys, the serum samples of 252 squirrel monkeys from 9 zoological gardens in Japan were tested by ELISA using plasmid-encoded Yersinia outer membrane protein (Yops) as the antigen. The cutoff value was calculated by using the serum samples of the squirrel monkeys from Suriname, where no prevalence of pathogenic Yersinia have been reported. According to the cutoff value, 164 of 252 (65.1%) squirrel monkeys were considered positive against pathogenic Yersinia. These positive monkeys belonged to 8 of the 9 zoological gardens, and the percentage of the seropositive monkeys ranged from 22.2 to 89.4%. Furthermore, in one zoological garden, the positive rate of the squirrel monkeys which were over 1 year old (95.7%) was significantly higher than those which were under 1 year old (23.3%). These results suggested that pathogenic Yersinia is highly prevalent among breeding monkeys in Japan.

Prevalence of gastrointestinal bacterial pathogens in a population of zoo animals.

PubMed

Stirling, J; Griffith, M; Blair, I; Cormican, M; Dooley, J S G; Goldsmith, C E; Glover, S G; Loughrey, A; Lowery, C J; Matsuda, M; McClurg, R; McCorry, K; McDowell, D; McMahon, A; Cherie Millar, B; Nagano, Y; Rao, J R; Rooney, P J; Smyth, M; Snelling, W J; Xu, J; Moore, J E

2008-04-01

Faecal prevalence of gastrointestinal bacterial pathogens, including Campylobacter, Escherichia coli O157:H7, Salmonella, Shigella, Yersinia, as well as Arcobacter, were examined in 317 faecal specimens from 44 animal species in Belfast Zoological Gardens, during July-September 2006. Thermophilic campylobacters including Campylobacter jejuni, Campylobacter coli and Campylobacter lari, were the most frequently isolated pathogens, where members of this genus were isolated from 11 animal species (11 of 44; 25%). Yersinia spp. were isolated from seven animal species (seven of 44; 15.9%) and included, Yersinia enterocolitica (five of seven isolates; 71.4%) and one isolate each of Yersinia frederiksenii and Yersinia kristensenii. Only one isolate of Salmonella was obtained throughout the entire study, which was an isolate of Salmonella dublin (O 1,9,12: H g, p), originating from tiger faeces after enrichment. None of the animal species found in public contact areas of the zoo were positive for any gastrointestinal bacterial pathogens. Also, water from the lake in the centre of the grounds, was examined for the same bacterial pathogens and was found to contain C. jejuni. This study is the first report on the isolation of a number of important bacterial pathogens from a variety of novel host species, C. jejuni from the red kangaroo (Macropus rufus), C. lari from a maned wolf (Chrysocyon brachyurus), Y. kristensenii from a vicugna (Vicugna vicugna) and Y. enterocolitica from a maned wolf and red panda (Ailurus fulgens). In conclusion, this study demonstrated that the faeces of animals in public contact areas of the zoo were not positive for the bacterial gastrointestinal pathogens examined. This is reassuring for the public health of visitors, particularly children, who enjoy this educational and recreational resource.

Selective isolation of Yersinia pestis from plague-infected fleas

PubMed Central

Sarovich, Derek S.; Colman, Rebecca E.; Price, Erin P.; Chung, Wai Kwan; Lee, Judy; Schupp, James M.; Alexander, James; Keim, Paul; Wagner., David M.

2010-01-01

We evaluated Yersinia CIN agar for the isolation of Yersinia pestis from infected fleas. CIN media is effective for the differentiation of Y. pestis from flea commensal flora and is sufficiently inhibitory to other bacteria that typically outcompete Y. pestis after 48 hours of growth using less selective media. PMID:20385178

Draft Genome Sequence of the Fish Pathogen Yersinia ruckeri Strain 37551, Serotype O1b, Isolated from Diseased, Vaccinated Atlantic Salmon (Salmo salar) in Chile

PubMed Central

Navas, Esteban; Bohle, Harry; Henríquez, Patricio; Grothusen, Horst; Bustamante, Fernando; Bustos, Patricio

2014-01-01

We sequenced the genome of a motile O1b Yersinia ruckeri field isolate from Chile, which is causing enteric redmouth disease (ERM) in vaccinated Atlantic salmon (Salmo salar). The draft genome has 3,775,486 bp, a G+C content of 47.1%, and is predicted to contain 3,406 coding sequences. PMID:25169862

Insights into the genome evolution of Yersinia pestis through whole genome comparison with Yersinia pseudotuberculosis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Souza, B; Stoutland, P; Derbise, A

2004-01-24

Yersinia pestis, the causative agent of plague, is a highly uniform clone that diverged recently from the enteric pathogen Yersinia pseudotuberculosis. Despite their close genetic relationship, they differ radically in their pathogenicity and transmission. Here we report the complete genomic sequence of Y. pseudotuberculosis IP32953 and its use for detailed genome comparisons to available Y. pestis sequences. Analyses of identified differences across a panel of Yersinia isolates from around the world reveals 32 Y. pestis chromosomal genes that, together with the two Y. pestis-specific plasmids, represent the only new genetic material in Y. pestis acquired since the divergence from Y.more » pseudotuberculosis. In contrast, 149 new pseudogenes (doubling the previous estimate) and 317 genes absent from Y. pestis were detected, indicating that as many as 13% of Y. pseudotuberculosis genes no longer function in Y. pestis. Extensive IS-mediated genome rearrangements and reductive evolution through massive gene loss, resulting in elimination and modification of pre-existing gene expression pathways appear to be more important than acquisition of new genes in the evolution of Y. pestis. These results provide a sobering example of how a highly virulent epidemic clone can suddenly emerge from a less virulent, closely related progenitor.« less

Caspase-12 and the inflammatory response to Yersinia pestis.

PubMed

Ferwerda, Bart; McCall, Matthew B B; de Vries, Maaike C; Hopman, Joost; Maiga, Boubacar; Dolo, Amagana; Doumbo, Ogobara; Daou, Modibo; de Jong, Dirk; Joosten, Leo A B; Tissingh, Rudi A; Reubsaet, Frans A G; Sauerwein, Robert; van der Meer, Jos W M; van der Ven, André J A M; Netea, Mihai G

2009-09-01

Caspase-12 functions as an antiinflammatory enzyme inhibiting caspase-1 and the NOD2/RIP2 pathways. Due to increased susceptibility to sepsis in individuals with functional caspase-12, an early-stop mutation leading to the loss of caspase-12 has replaced the ancient genotype in Eurasia and a significant proportion of individuals from African populations. In African-Americans, it has been shown that caspase-12 inhibits the pro-inflammatory cytokine production. We assessed whether similar mechanisms are present in African individuals, and whether evolutionary pressures due to plague may have led to the present caspase-12 genotype population frequencies. No difference in cytokine induction through the caspase-1 and/or NOD2/RIP2 pathways was observed in two independent African populations, among individuals with either an intact or absent caspase-12. In addition, stimulations with Yersinia pestis and two other species of Yersinia were preformed to investigate whether caspase-12 modulates the inflammatory reaction induced by Yersinia. We found that caspase-12 did not modulate cytokine production induced by Yersinia spp. Our experiments demonstrate for the first time the involvement of the NOD2/RIP2 pathway for recognition of Yersinia. However, caspase-12 does not modulate innate host defense against Y. pestis and alternative explanations for the geographical distribution of caspase-12 should be sought.

Development of a rapid serotyping method for Salmonella enterica using serotype-specific single-nucleotide polymorphisms

USDA-ARS?s Scientific Manuscript database

Salmonella enterica subsp. enterica serotype Enteriditis (S. Enteriditis) is the leading cause of salmonellosis worldwide, including the USA. Many S. enterica serotypes known to cause foodborne disease are associated with broiler meat contamination. While some serotypes are specific to birds (S. e...

Protective efficacy of recombinant Yersinia outer proteins against bubonic plague caused by encapsulated and nonencapsulated Yersinia pestis.

PubMed

Andrews, G P; Strachan, S T; Benner, G E; Sample, A K; Anderson, G W; Adamovicz, J J; Welkos, S L; Pullen, J K; Friedlander, A M

1999-03-01

To evaluate the role of Yersinia outer proteins (Yops) in conferring protective immunity against plague, six yop loci from Yersinia pestis were individually amplified by PCR, cloned, and expressed in Escherichia coli. The recombinant proteins were purified and injected into mice. Most Yop-vaccinated animals succumbed to infection with either wild-type encapsulated Y. pestis or a virulent, nonencapsulated isogenic variant. Vaccination with YpkA significantly prolonged mean survival time but did not increase overall survival of mice infected with the nonencapsulated strain. The only significant protection against death was observed in YopD-vaccinated mice challenged with the nonencapsulated strain.

The elusive activity of the Yersinia protein kinase A kinase domain is revealed.

PubMed

Laskowski-Arce, Michelle A; Orth, Kim

2007-10-01

Yersinia spp. pathogens use their type III secretion system to translocate effectors that manipulate host signaling pathways during infection. Although molecular targets for five of the six known Yersinia effectors are known, the target for the serine/threonine kinase domain of Yersinia protein kinase A (YpkA) has remained elusive. Recently, Navarro et al. (2007) demonstrated that YpkA phosphorylates Galphaq, and inhibits Galphaq-mediated signaling. Inhibition by YpkA could contribute to one of the most documented symptoms of Yersinia pestis infection, extensive bleeding.

[Advance on genome research of Yersinia pestis bacteriophage].

PubMed

Tan, H L; Wang, P; Li, W

2017-04-10

Completion of the genome sequences on Yersinia pestis bacteriophage offered unprecedented opportunity for researchers to carry out related genomic studies. This review was based on the genomic sequences and provided a genomic perspective in describing the essential features of genome on Yersinia pestis bacteriophage. Based on the comparative genomics, genetic evolutionary relationship was discussed. Description of functions from the gene prediction and protein annotation provided evidence for further related studies.

Draft Genome Sequence of the Fish Pathogen Yersinia ruckeri Strain 37551, Serotype O1b, Isolated from Diseased, Vaccinated Atlantic Salmon (Salmo salar) in Chile.

PubMed

Navas, Esteban; Bohle, Harry; Henríquez, Patricio; Grothusen, Horst; Bustamante, Fernando; Bustos, Patricio; Mancilla, Marcos

2014-08-28

We sequenced the genome of a motile O1b Yersinia ruckeri field isolate from Chile, which is causing enteric redmouth disease (ERM) in vaccinated Atlantic salmon (Salmo salar). The draft genome has 3,775,486 bp, a G+C content of 47.1%, and is predicted to contain 3,406 coding sequences. Copyright © 2014 Navas et al.

Haemophilus influenzae serotype a meningitis.

PubMed

de Pádua, Rubia Andreia Falleiros; de Lima Scodro, Regiane Bertin; Ghiraldi, Luciana Dias; Siqueira, Vera Lúcia Dias; Yamashita, Yandara Keiko; Helbel, César; Cardoso, Rosilene Fressatti

2009-01-01

This work describes a case of Haemophilus influenzae serotype a meningitis in Brazil, after almost a decade since the introduction of Haemophilus influenzae serotype b conjugate vaccine. Uncertainty about the replacement of H. influenzae serotypes as a cause of invasive diseases justifies continuous surveillance, coupled with investigations of carriage rates and requirements of chemoprophylaxis in contact persons.

Growth and survival kinetics of Yersinia enterocolitica IP 383 0:9 as affected by equimolar concentrations of undissociated short-chain organic acids.

PubMed

el-Ziney, M G; De Meyer, H; Debevere, J M

1997-03-03

The influence of different organic acids (lactic, acetic, formic and propionic acids) at equimolar concentrations of undissociated acid with pH range of 3.9, 5.8, on the aerobic and anaerobic growth and survival kinetics of the virulent strain of Y. enterocolitica IP 383 0:9, was determined in tryptone soy broth at 4 degrees C. Growth and survival data were analyzed and fitted by a modification of the Whiting and Cygnarowicz-Provost model, using the Minpack software library. Initial generation times, initial specific growth rates, lag time and dead rate were subsequently calculated from the model parameters. The results demonstrate that the inhibitory effects of the acids were divided into two categories dependent upon pH. At high pH (5.8) the order of inhibition was formic acid > acetic acid > propionic acid > lactic acid, whereas at lower pH it became formic acid > lactic acid > acetic acid > propionic acid. The inhibitory effect of lactic acid is enhanced under anaerobic condition. Nevertheless, when the organism was cultured anaerobically, it was shown to be more tolerant to formic and acetic acids. Moreover, these variables (type of organic acid, pH and atmosphere) did not lead to the loss of the virulence plasmid in growing and surviving cells. The mechanism of inhibitory effect for each of the acids are also discussed.

Serotyping of Actinobacillus pleuropneumoniae serotype 5 strains using a monoclonal-based polystyrene agglutination test.

PubMed Central

Dubreuil, J D; Letellier, A; Stenbaek, E; Gottschalk, M

1996-01-01

A polystyrene agglutination test has been developed for serotyping Actinobacillus pleuropneumoniae serotype 5a and 5b strains. Protein A-coated polystyrene microparticles were sensitized with a murine monoclonal antibody recognizing an epitope on serotype 5 LPS-O chain as shown by SDS-PAGE and Western blotting. A total of 205 A. pleuropneumoniae, strains including all 12 serotype reference strains and 13 strains representing 8 common bacterial species associated with swine or related to A. pleuropneumoniae, were tested by mixing 25 microL of polystyrene reagent with the same volume of a dense suspension of bacterial cells grown for 18 h. All A. pleuropneumoniae strains had been previously serotyped using standard procedures. The polystyrene agglutination test was rapid (less than 3 min) and easy to perform. Overall a very good correlation (97.3%) with the standard techniques was found. The sensitized polystyrene particles were stable for at least 6 mo. Images Figure 1. PMID:8825998

[First case of lung abscess due to Yersinia pseudotuberculosis in Japan].

PubMed

Takahashi, Yoshinori; Sasabe, Jun; Maeda, Hikaru; Fujiwara, Atsushi; Yuda, Hisamichi; Yoshida, Masamichi; Taguchi, Osamu

2014-07-01

A 63-year-old previously healthy man was admitted to our hospital with diarrhea that had lasted for about 4 weeks, high fever and dyspnea. Chest computed tomography showed consolidation with a low-density area in the right middle lobe and small nodules with feeding vessels in the right upper lobe. On Day 8, a cavity was observed in the consolidation, and the lymph nodes in the mediastinum became necrotic. Yersinia pseudotuberculosis (serotype 4b) was cultured from blood, bronchial washing fluid, and lung tissue specimens. We diagnosed the lung lesions as septic pulmonary embolism caused by enterocolitis. We started treatment with tazobactam/piperacillin. It has been reported that high-dose ceftriaxone (CTRX) is effective, but CTRX at normal doses and other beta-lactams are less effective or even ineffective. Therefore, we changed to CTRX (4g/day) on Day 5, CTRX (2g/day) on Day 8, and oral cefditoren pivoxil (600 mg/day; a third-generation cephalosporin) on Day 18. Antibiotic therapy resulted in a favorable response. The patient was discharged from our hospital on day 25 in good health. To the best of our knowledge, this is the first case of a lung abscess caused by Y. pseudotuberculosis reported in Japan.

Engineering of Yersinia Phytases to Improve Pepsin and Trypsin Resistance and Thermostability and Application Potential in the Food and Feed Industry.

PubMed

Niu, Canfang; Yang, Peilong; Luo, Huiying; Huang, Huoqing; Wang, Yaru; Yao, Bin

2017-08-30

Susceptibility to proteases usually limits the application of phytase. We sought to improve the pepsin and trypsin resistance of YeAPPA from Yersinia enterocolitica and YkAPPA from Y. kristensenii by optimizing amino acid polarity and charge. The predicted pepsin/trypsin cleavage sites F89/K226 in pepsin/trypsin-sensitive YeAPPA and the corresponding sites (F89/E226) in pepsin-sensitive but trypsin-resistant YkAPPA were substituted with S and H, respectively. Six variants were produced in Pichia pastoris for catalytic and biochemical characterization. F89S, E226H, and F89S/E226H elevated pepsin resistance and thermostability and K226H and F89S/K226H improved pepsin and trypsin resistance and stability at 60 °C and low pH. All the variants increased the ability of the proteins to hydrolyze phytate in corn meal by 2.6-14.9-fold in the presence of pepsin at 37 °C and low pH. This study developed a genetic manipulation strategy specific for pepsin/trypsin-sensitive phytases that can improve enzyme tolerance against proteases and heat and benefit the food and feed industry in a cost-effective way.

Molecular analysis of the genes involved in the biosynthesis of serotype specific polysaccharide in the novel serotype k strains of Streptococcus mutans.

PubMed

Nomura, R; Nakano, K; Ooshima, T

2005-10-01

We previously reported the new serotype k of Streptococcus mutans, which, compared to serotypes c, e, and f, features a drastic reduction in the length of the glucose side chain linked to the rhamnose backbone of the serotype specific polysaccharide. The 5' region of the rgpF gene of serotype k strains contains a distinctive nucleotide sequence, which suggests that an alteration of the rgpF gene in serotype k strains may explain the shortened glucose side chain. However, in the present study, expression of the rgpF gene of MT8148 (serotype c) in serotype k isolates was not found to lead to serotype conversion. Furthermore, mRNA expression of rgpE, known to be associated with glucose side chain formation, was not detected in any of the tested serotype k isolates with an RT-PCR method. The nucleotide alignment of all genes known to be involved in the biosynthesis of serotype specific polysaccharide in serotype k strains was shown to be quite similar to that of serotype c strains, as compared to serotype e and f strains, especially in the region downstream of rgpF. Our results indicate that the common characteristics of serotype k isolates may be caused by a lack of expression of the gene involved in glucose side chain formation.

Microgravity Effects on Yersinia Pestis Virulence

NASA Astrophysics Data System (ADS)

Lawal, A.; Abogunde, O.; Jejelowo, O.; Rosenzweig, J.-A.

2010-04-01

Microgravity effects on Yersinia pestis proliferation, cold growth, and type three secretion system function were evaluated in macrophage cell infections, HeLa cell infections, and cold growth plate assays.

Serotyping of Streptococcus pneumoniae Based on Capsular Genes Polymorphisms

PubMed Central

Raymond, Frédéric; Boucher, Nancy; Allary, Robin; Robitaille, Lynda; Lefebvre, Brigitte; Tremblay, Cécile

2013-01-01

Streptococcus pneumoniae serotype epidemiology is essential since serotype replacement is a concern when introducing new polysaccharide-conjugate vaccines. A novel PCR-based automated microarray assay was developed to assist in the tracking of the serotypes. Autolysin, pneumolysin and eight genes located in the capsular operon were amplified using multiplex PCR. This step was followed by a tagged fluorescent primer extension step targeting serotype-specific polymorphisms. The tagged primers were then hybridized to a microarray. Results were exported to an expert system to identify capsular serotypes. The assay was validated on 166 cultured S. pneumoniae samples from 63 different serotypes as determined by the Quellung method. We show that typing only 12 polymorphisms located in the capsular operon allows the identification at the serotype level of 22 serotypes and the assignation of 24 other serotypes to a subgroup of serotypes. Overall, 126 samples (75.9%) were correctly serotyped, 14 were assigned to a member of the same serogroup, 8 rare serotypes were erroneously serotyped, and 18 gave negative serotyping results. Most of the discrepancies involved rare serotypes or serotypes that are difficult to discriminate using a DNA-based approach, for example 6A and 6B. The assay was also tested on clinical specimens including 43 cerebrospinal fluid samples from patients with meningitis and 59 nasopharyngeal aspirates from bacterial pneumonia patients. Overall, 89% of specimens positive for pneumolysin were serotyped, demonstrating that this method does not require culture to serotype clinical specimens. The assay showed no cross-reactivity for 24 relevant bacterial species found in these types of samples. The limit of detection for serotyping and S. pneumoniae detection was 100 genome equivalent per reaction. This automated assay is amenable to clinical testing and does not require any culturing of the samples. The assay will be useful for the evaluation of serotype

Nucleotide sequences specific to Yersinia pestis and methods for the detection of Yersinia pestis

DOEpatents

McCready, Paula M [Tracy, CA; Radnedge, Lyndsay [San Mateo, CA; Andersen, Gary L [Berkeley, CA; Ott, Linda L [Livermore, CA; Slezak, Thomas R [Livermore, CA; Kuczmarski, Thomas A [Livermore, CA; Motin, Vladinir L [League City, TX

2009-02-24

Nucleotide sequences specific to Yersinia pestis that serve as markers or signatures for identification of this bacterium were identified. In addition, forward and reverse primers and hybridization probes derived from these nucleotide sequences that are used in nucleotide detection methods to detect the presence of the bacterium are disclosed.

Parallel independent evolution of pathogenicity within the genus Yersinia

PubMed Central

Reuter, Sandra; Connor, Thomas R.; Barquist, Lars; Walker, Danielle; Feltwell, Theresa; Harris, Simon R.; Fookes, Maria; Hall, Miquette E.; Petty, Nicola K.; Fuchs, Thilo M.; Corander, Jukka; Dufour, Muriel; Ringwood, Tamara; Savin, Cyril; Bouchier, Christiane; Martin, Liliane; Miettinen, Minna; Shubin, Mikhail; Riehm, Julia M.; Laukkanen-Ninios, Riikka; Sihvonen, Leila M.; Siitonen, Anja; Skurnik, Mikael; Falcão, Juliana Pfrimer; Fukushima, Hiroshi; Scholz, Holger C.; Prentice, Michael B.; Wren, Brendan W.; Parkhill, Julian; Carniel, Elisabeth; Achtman, Mark; McNally, Alan; Thomson, Nicholas R.

2014-01-01

The genus Yersinia has been used as a model system to study pathogen evolution. Using whole-genome sequencing of all Yersinia species, we delineate the gene complement of the whole genus and define patterns of virulence evolution. Multiple distinct ecological specializations appear to have split pathogenic strains from environmental, nonpathogenic lineages. This split demonstrates that contrary to hypotheses that all pathogenic Yersinia species share a recent common pathogenic ancestor, they have evolved independently but followed parallel evolutionary paths in acquiring the same virulence determinants as well as becoming progressively more limited metabolically. Shared virulence determinants are limited to the virulence plasmid pYV and the attachment invasion locus ail. These acquisitions, together with genomic variations in metabolic pathways, have resulted in the parallel emergence of related pathogens displaying an increasingly specialized lifestyle with a spectrum of virulence potential, an emerging theme in the evolution of other important human pathogens. PMID:24753568

Technologies and Techniques for Early Warning Systems to Monitor and Evaluate Drinking Water Quality: A State-of-the-Art Review

DTIC Science & Technology

2005-08-25

tests currently available are the same as BTA with the inclusion of Vibrio cholerae O1. The detection limits of bacteria are 10 cfu/mL and for...spp., Burkholderia spp., Campylobacter spp., Clostridium perfringens, E. coli O157:H7, Francisella tularensis, Salmonella typhi, Shigella spp., Vibrio ... cholerae O1, Yersinia pestis, Y. enterocolitica Viruses Caliciviruses, Enteroviruses, Hepatitis A/E, Variola, Venezuelan equine encephalitis virus

Early Divergent Strains of Yersinia pestis in Eurasia 5,000 Years Ago

PubMed Central

Rasmussen, Simon; Allentoft, Morten Erik; Nielsen, Kasper; Orlando, Ludovic; Sikora, Martin; Sjögren, Karl-Göran; Pedersen, Anders Gorm; Schubert, Mikkel; Van Dam, Alex; Kapel, Christian Moliin Outzen; Nielsen, Henrik Bjørn; Brunak, Søren; Avetisyan, Pavel; Epimakhov, Andrey; Khalyapin, Mikhail Viktorovich; Gnuni, Artak; Kriiska, Aivar; Lasak, Irena; Metspalu, Mait; Moiseyev, Vyacheslav; Gromov, Andrei; Pokutta, Dalia; Saag, Lehti; Varul, Liivi; Yepiskoposyan, Levon; Sicheritz-Pontén, Thomas; Foley, Robert A.; Lahr, Marta Mirazón; Nielsen, Rasmus; Kristiansen, Kristian; Willerslev, Eske

2015-01-01

Summary The bacteria Yersinia pestis is the etiological agent of plague and has caused human pandemics with millions of deaths in historic times. How and when it originated remains contentious. Here, we report the oldest direct evidence of Yersinia pestis identified by ancient DNA in human teeth from Asia and Europe dating from 2,800 to 5,000 years ago. By sequencing the genomes, we find that these ancient plague strains are basal to all known Yersinia pestis. We find the origins of the Yersinia pestis lineage to be at least two times older than previous estimates. We also identify a temporal sequence of genetic changes that lead to increased virulence and the emergence of the bubonic plague. Our results show that plague infection was endemic in the human populations of Eurasia at least 3,000 years before any historical recordings of pandemics. PMID:26496604

Transcriptome Changes Associated with Anaerobic Growth in Yersinia intermedia (ATCC29909)

PubMed Central

Kiley, Patricia J.; Glasner, Jeremy D.; Perna, Nicole T.

2013-01-01

Background The yersiniae (Enterobacteriaceae) occupy a variety of niches, including some in human and flea hosts. Metabolic adaptations of the yersiniae, which contribute to their success in these specialized environments, remain largely unknown. We report results of an investigation of the transcriptome under aerobic and anaerobic conditions for Y. intermedia, a non-pathogenic member of the genus that has been used as a research surrogate for Y. pestis. Y. intermedia shares characteristics of pathogenic yersiniae, but is not known to cause disease in humans. Oxygen restriction is an important environmental stimulus experienced by many bacteria during their life-cycles and greatly influences their survival in specific environments. How oxygen availability affects physiology in the yersiniae is of importance in their life cycles but has not been extensively characterized. Methodology/Principal Findings Tiled oligonucleotide arrays based on a draft genome sequence of Y. intermedia were used in transcript profiling experiments to identify genes that change expression in response to oxygen availability during growth in minimal media with glucose. The expression of more than 400 genes, constituting about 10% of the genome, was significantly altered due to oxygen-limitation in early log phase under these conditions. Broad functional categorization indicated that, in addition to genes involved in central metabolism, genes involved in adaptation to stress and genes likely involved with host interactions were affected by oxygen-availability. Notable among these, were genes encoding functions for motility, chemotaxis and biosynthesis of cobalamin, which were up-regulated and those for iron/heme utilization, methionine metabolism and urease, which were down-regulated. Conclusions/Significance This is the first transcriptome analysis of a non-pathogenic Yersinia spp. and one of few elucidating the global response to oxygen limitation for any of the yersiniae. Thus this study

Transcriptome changes associated with anaerobic growth in Yersinia intermedia (ATCC29909).

PubMed

Babujee, Lavanya; Balakrishnan, Venkatesh; Kiley, Patricia J; Glasner, Jeremy D; Perna, Nicole T

2013-01-01

The yersiniae (Enterobacteriaceae) occupy a variety of niches, including some in human and flea hosts. Metabolic adaptations of the yersiniae, which contribute to their success in these specialized environments, remain largely unknown. We report results of an investigation of the transcriptome under aerobic and anaerobic conditions for Y. intermedia, a non-pathogenic member of the genus that has been used as a research surrogate for Y. pestis. Y. intermedia shares characteristics of pathogenic yersiniae, but is not known to cause disease in humans. Oxygen restriction is an important environmental stimulus experienced by many bacteria during their life-cycles and greatly influences their survival in specific environments. How oxygen availability affects physiology in the yersiniae is of importance in their life cycles but has not been extensively characterized. Tiled oligonucleotide arrays based on a draft genome sequence of Y. intermedia were used in transcript profiling experiments to identify genes that change expression in response to oxygen availability during growth in minimal media with glucose. The expression of more than 400 genes, constituting about 10% of the genome, was significantly altered due to oxygen-limitation in early log phase under these conditions. Broad functional categorization indicated that, in addition to genes involved in central metabolism, genes involved in adaptation to stress and genes likely involved with host interactions were affected by oxygen-availability. Notable among these, were genes encoding functions for motility, chemotaxis and biosynthesis of cobalamin, which were up-regulated and those for iron/heme utilization, methionine metabolism and urease, which were down-regulated. This is the first transcriptome analysis of a non-pathogenic Yersinia spp. and one of few elucidating the global response to oxygen limitation for any of the yersiniae. Thus this study lays the foundation for further experimental characterization of

Detection of serotype k Streptococcus mutans in Thai subjects.

PubMed

Lapirattanakul, J; Nakano, K; Nomura, R; Nemoto, H; Kojima, A; Senawongse, P; Srisatjaluk, R; Ooshima, T

2009-10-01

Streptococcus mutans, known to be a pathogen of dental caries as well as bacteremia and infective endocarditis, is classified into four serotypes, c, e, f and k, based on the structures of serotype-specific polysaccharides. Serotype k was recently designated using blood isolates from Japanese subjects and such strains are considered to be virulent in the bloodstream. The purpose of the present study was to analyse the serotype distribution of strains isolated from Thai subjects and determine whether serotype k strains were present. A total of 250 S. mutans strains were isolated from 50 Thai subjects, and serotypes of all strains were determined. Then, molecular and biological analyses were carried out for serotype k strains. Immunodiffusion and polymerase chain reaction analyses showed that serotype c was the most prevalent (70%), followed by serotypes e (22.8%), f (4.4%) and k (2.8%), which indicated that serotype k S. mutans strains occurred in Thai individuals at a similar rate to that previously reported for Japanese and Finnish populations. Molecular analyses of the seven serotype k strains showed extremely low expression of rgpE, which is related to glucose side-chain formation in serotype-specific rhamnose-glucose polymers, similar to previous reports for those other populations. In addition, analysis of the biological properties of the seven serotype k strains demonstrated low levels of sucrose-dependent adhesion, cellular hydrophobicity, dextran-binding activity and phagocytosis susceptibility by human polymorphonuclear leukocytes, which are characteristics similar to those of serotype k strains previously isolated in Japan. Our results indicate the possibility of a worldwide prevalence of serotype k strains with properties in common with those of previously reported strains.

Typing and Clustering of Yersinia pseudotuberculosis Isolates by Restriction Fragment Length Polymorphism Analysis Using Insertion Sequences

PubMed Central

Voskresenskaya, E.; Savin, C.; Leclercq, A.; Tseneva, G.

2014-01-01

Yersinia pseudotuberculosis is an enteropathogen that has an animal reservoir and causes human infections, mostly in temperate and cold countries. Most of the methods previously used to subdivide Y. pseudotuberculosis were performed on small numbers of isolates from a specific geographical area. One aim of this study was to evaluate the typing efficiency of restriction fragment length polymorphism of insertion sequence hybridization patterns (IS-RFLP) compared to other typing methods, such as serotyping, ribotyping, and multilocus sequence typing (MLST), on the same set of 80 strains of Y. pseudotuberculosis of global origin. We found that IS100 was not adequate for IS-RFLP but that both IS285 and IS1541 efficiently subtyped Y. pseudotuberculosis. The discriminatory index (DI) of IS1541-RFLP (0.980) was superior to those of IS285-RFLP (0.939), ribotyping (0.944), MLST (0.861), and serotyping (0.857). The combination of the two IS (2IS-RFLP) further increased the DI to 0.998. Thus, IS-RFLP is a powerful tool for the molecular typing of Y. pseudotuberculosis and has the advantage of exhibiting well-resolved banding patterns that allow for a reliable comparison of strains of worldwide origin. The other aim of this study was to assess the clustering power of IS-RFLP. We found that 2IS-RFLP had a remarkable capacity to group strains with similar genotypic and phenotypic markers, thus identifying robust populations within Y. pseudotuberculosis. Our study thus demonstrates that 2IS- and even IS1541-RFLP alone might be valuable tools for the molecular typing of global isolates of Y. pseudotuberculosis and for the analysis of the population structure of this species. PMID:24671793

Regulatory principles governing Salmonella and Yersinia virulence

PubMed Central

Erhardt, Marc; Dersch, Petra

2015-01-01

Enteric pathogens such as Salmonella and Yersinia evolved numerous strategies to survive and proliferate in different environmental reservoirs and mammalian hosts. Deciphering common and pathogen-specific principles for how these bacteria adjust and coordinate spatiotemporal expression of virulence determinants, stress adaptation, and metabolic functions is fundamental to understand microbial pathogenesis. In order to manage sudden environmental changes, attacks by the host immune systems and microbial competition, the pathogens employ a plethora of transcriptional and post-transcriptional control elements, including transcription factors, sensory and regulatory RNAs, RNAses, and proteases, to fine-tune and control complex gene regulatory networks. Many of the contributing global regulators and the molecular mechanisms of regulation are frequently conserved between Yersinia and Salmonella. However, the interplay, arrangement, and composition of the control elements vary between these closely related enteric pathogens, which generate phenotypic differences leading to distinct pathogenic properties. In this overview we present common and different regulatory networks used by Salmonella and Yersinia to coordinate the expression of crucial motility, cell adhesion and invasion determinants, immune defense strategies, and metabolic adaptation processes. We highlight evolutionary changes of the gene regulatory circuits that result in different properties of the regulatory elements and how this influences the overall outcome of the infection process. PMID:26441883

High-throughput analysis of Yersinia pseudotuberculosis gene essentiality in optimised in vitro conditions, and implications for the speciation of Yersinia pestis.

PubMed

Willcocks, Samuel J; Stabler, Richard A; Atkins, Helen S; Oyston, Petra F; Wren, Brendan W

2018-05-31

Yersinia pseudotuberculosis is a zoonotic pathogen, causing mild gastrointestinal infection in humans. From this comparatively benign pathogenic species emerged the highly virulent plague bacillus, Yersinia pestis, which has experienced significant genetic divergence in a relatively short time span. Much of our knowledge of Yersinia spp. evolution stems from genomic comparison and gene expression studies. Here we apply transposon-directed insertion site sequencing (TraDIS) to describe the essential gene set of Y. pseudotuberculosis IP32953 in optimised in vitro growth conditions, and contrast these with the published essential genes of Y. pestis. The essential genes of an organism are the core genetic elements required for basic survival processes in a given growth condition, and are therefore attractive targets for antimicrobials. One such gene we identified is yptb3665, which encodes a peptide deformylase, and here we report for the first time, the sensitivity of Y. pseudotuberculosis to actinonin, a deformylase inhibitor. Comparison of the essential genes of Y. pseudotuberculosis with those of Y. pestis revealed the genes whose importance are shared by both species, as well as genes that were differentially required for growth. In particular, we find that the two species uniquely rely upon different iron acquisition and respiratory metabolic pathways under similar in vitro conditions. The discovery of uniquely essential genes between the closely related Yersinia spp. represent some of the fundamental, species-defining points of divergence that arose during the evolution of Y. pestis from its ancestor. Furthermore, the shared essential genes represent ideal candidates for the development of novel antimicrobials against both species.

Early divergent strains of Yersinia pestis in Eurasia 5,000 years ago.

PubMed

Rasmussen, Simon; Allentoft, Morten Erik; Nielsen, Kasper; Orlando, Ludovic; Sikora, Martin; Sjögren, Karl-Göran; Pedersen, Anders Gorm; Schubert, Mikkel; Van Dam, Alex; Kapel, Christian Moliin Outzen; Nielsen, Henrik Bjørn; Brunak, Søren; Avetisyan, Pavel; Epimakhov, Andrey; Khalyapin, Mikhail Viktorovich; Gnuni, Artak; Kriiska, Aivar; Lasak, Irena; Metspalu, Mait; Moiseyev, Vyacheslav; Gromov, Andrei; Pokutta, Dalia; Saag, Lehti; Varul, Liivi; Yepiskoposyan, Levon; Sicheritz-Pontén, Thomas; Foley, Robert A; Lahr, Marta Mirazón; Nielsen, Rasmus; Kristiansen, Kristian; Willerslev, Eske

2015-10-22

The bacteria Yersinia pestis is the etiological agent of plague and has caused human pandemics with millions of deaths in historic times. How and when it originated remains contentious. Here, we report the oldest direct evidence of Yersinia pestis identified by ancient DNA in human teeth from Asia and Europe dating from 2,800 to 5,000 years ago. By sequencing the genomes, we find that these ancient plague strains are basal to all known Yersinia pestis. We find the origins of the Yersinia pestis lineage to be at least two times older than previous estimates. We also identify a temporal sequence of genetic changes that lead to increased virulence and the emergence of the bubonic plague. Our results show that plague infection was endemic in the human populations of Eurasia at least 3,000 years before any historical recordings of pandemics. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Real-time multiplex PCR assay for detection of Yersinia pestis and Yersinia pseudotuberculosis.

PubMed

Matero, Pirjo; Pasanen, Tanja; Laukkanen, Riikka; Tissari, Päivi; Tarkka, Eveliina; Vaara, Martti; Skurnik, Mikael

2009-01-01

A multiplex real-time polymerase chain reaction (PCR) assay was developed for the detection of Yersinia pestis and Yersinia pseudotuberculosis. The assay includes four primer pairs, two of which are specific for Y. pestis, one for Y. pestis and Y. pseudotuberculosis and one for bacteriophage lambda; the latter was used as an internal amplification control. The Y. pestis-specific target genes in the assay were ypo2088, a gene coding for a putative methyltransferase, and the pla gene coding for the plasminogen activator. In addition, the wzz gene was used as a target to specifically identify both Y. pestis and the closely related Y. pseudotuberculosis group. The primer and probe sets described for the different genes can be used either in single or in multiplex PCR assays because the individual probes were designed with different fluorochromes. The assays were found to be both sensitive and specific; the lower limit of the detection was 10-100 fg of extracted Y. pestis or Y. pseudotuberculosis total DNA. The sensitivity of the tetraplex assay was determined to be 1 cfu for the ypo2088 and pla probe labelled with FAM and JOE fluorescent dyes, respectively.

Around the World in 1,475 Salmonella Geo-serotypes

PubMed Central

Le Hello, Simon; de Jong, Birgitta; Rolfhamre, Per; Faensen, Daniel; Weill, François-Xavier; Giesecke, Johan

2016-01-01

It’s easy to remember Salmonella serotypes names, isn’t it? Surely, this is because the naming system of Salmonella serotypes is by far the most scientist friendly. Traditionally, most Salmonella serotypes have been named after geographic locations. We decided to explore the geographic locations to which Salmonella serotypes refer and describe some unexpected twists in the naming scheme. We found that 93% (n = 1,475) of the 1,585 serotypes could be categorized as geo-serotypes; that is, the name refers to a geographic location. The 3 countries with the most geo-serotypes are Germany, the United Kingdom, and the United States. Other serotype names refer to the name of a person, animal, tribe, or food item or are a composite of symptoms and host. The Salmonella serotypes naming scheme has had a valuable effect on public health microbiology, and in the current era of fast development of whole-genome sequencing, it should remain a reference.

A mutli-omic systems approach to elucidating Yersinia virulence mechanisms

PubMed Central

Ansong, Charles; Schrimpe-Rutledge, Alexandra C.; Mitchell, Hugh; Chauhan, Sadhana; Jones, Marcus B.; Kim, Young-Mo; McAteer, Kathleen; Deatherage Kaiser, Brooke L.; Dubois, Jennifer L.; Brewer, Heather M.; Frank, Bryan C.; McDermott, Jason E.; Metz, Thomas O.; Peterson, Scott N.; Smith, Richard D.; Motin, Vladimir L.; Adkins, Joshua N.

2012-01-01

The underlying mechanisms that lead to dramatic differences between closely related pathogens are not always readily apparent. For example, the genomes of Yersinia pestis (YP) the causative agent of plague with a high mortality rate and Yersinia pseudotuberculosis (YPT) an enteric pathogen with a modest mortality rate are highly similar with some species specific differences; however the molecular causes of their distinct clinical outcomes remain poorly understood. In this study, a temporal multi-omic analysis of YP and YPT at physiologically relevant temperatures was performed to gain insights into how an acute and highly lethal bacterial pathogen, YP, differs from its less virulent progenitor, YPT. This analysis revealed higher gene and protein expression levels of conserved major virulence factors in YP relative to YPT, including the Yop virulon and the pH6 antigen. This suggests that adaptation in the regulatory architecture, in addition to the presence of unique genetic material, may contribute to the increased pathogenenicity of YP relative to YPT. Additionally, global transcriptome and proteome responses of YP and YPT revealed conserved post-transcriptional control of metabolism and the translational machinery including the modulation of glutamate levels in Yersiniae. Finally, the omics data was coupled with a computational network analysis, allowing an efficient prediction of novel Yersinia virulence factors based on gene and protein expression patterns. PMID:23147219

Oral vaccination against plague using Yersinia pseudotuberculosis.

PubMed

Demeure, Christian E; Derbise, Anne; Carniel, Elisabeth

2017-04-01

Yersinia pestis, the agent of plague, is among the deadliest bacterial pathogens affecting humans, and is a potential biological weapon. Because antibiotic resistant strains of Yersinia pestis have been observed or could be engineered for evil use, vaccination against plague might become the only means to reduce mortality. Although plague is re-emerging in many countries, a vaccine with worldwide license is currently lacking. The vaccine strategy described here is based on an oral vaccination with an attenuated strain of Yersinia pseudotuberculosis. Indeed, this species is genetically almost identical to Y. pestis, but has a much lower pathogenicity and a higher genomic stability. Gradual modifications of the wild-type Yersinia pseudotuberculosis strain IP32953 were performed to generate a safe and immunogenic vaccine. Genes coding for three essential virulence factors were deleted from this strain. To increase cross-species immunogenicity, an F1-encapsulated Y. pseudotuberculosis strain was then generated. For this, the Y. pestis caf operon, which encodes F1, was inserted first on a plasmid, and subsequently into the chromosome. The successive steps achieved to reach maximal vaccine potential are described, and how each step affected bacterial virulence and the development of a protective immune response is discussed. The final version of the vaccine, named VTnF1, provides a highly efficient and long-lasting protection against both bubonic and pneumonic plague after a single oral vaccine dose. Since a Y. pestis strain deprived of F1 exist or could be engineered, we also analyzed the protection conferred by the vaccine against such strain and found that it also confers full protection against the two forms of plague. Thus, the properties of VTnF1 makes it one of the most efficient candidate vaccine for mass vaccination in tropical endemic areas as well as for populations exposed to bioterrorism. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Group B streptococcus serotype prevalence in reproductive-age women at a tertiary care military medical center relative to global serotype distribution.

PubMed

Ippolito, Danielle L; James, Wesley A; Tinnemore, Deborah; Huang, Raywin R; Dehart, Mary J; Williams, Julie; Wingerd, Mark A; Demons, Samandra T

2010-11-24

Group B Streptococcus (GBS) serotype (Ia, Ib, II-IX) correlates with pathogen virulence and clinical prognosis. Epidemiological studies of seroprevalence are an important metric for determining the proportion of serotypes in a given population. The purpose of this study was to evaluate the prevalence of individual GBS serotypes at Madigan Healthcare System (Madigan), the largest military tertiary healthcare facility in the Pacific Northwestern United States, and to compare seroprevalences with international locations. To determine serotype distribution at Madigan, we obtained GBS isolates from standard-of-care anogenital swabs from 207 women of indeterminate gravidity between ages 18-40 during a five month interval. Serotype was determined using a recently described molecular method of polymerase chain reaction by capsular polysaccharide synthesis (cps) genes associated with pathogen virulence. Serotypes Ia, III, and V were the most prevalent (28%, 27%, and 17%, respectively). A systematic review of global GBS seroprevalence, meta-analysis, and statistical comparison revealed strikingly similar serodistibution at Madigan relative to civilian-sector populations in Canada and the United States. Serotype Ia was the only serotype consistently higher in North American populations relative to other geographic regions (p < 0.005). The number of non-typeable isolates was significantly lower in the study (p < 0.005). This study establishes PCR-based serotyping as a viable strategy for GBS epidemiological surveillance. Our results suggest that GBS seroprevalence remains stable in North America over the past two decades.

Group B streptococcus serotype prevalence in reproductive-age women at a tertiary care military medical center relative to global serotype distribution

PubMed Central

2010-01-01

Background Group B Streptococcus (GBS) serotype (Ia, Ib, II-IX) correlates with pathogen virulence and clinical prognosis. Epidemiological studies of seroprevalence are an important metric for determining the proportion of serotypes in a given population. The purpose of this study was to evaluate the prevalence of individual GBS serotypes at Madigan Healthcare System (Madigan), the largest military tertiary healthcare facility in the Pacific Northwestern United States, and to compare seroprevalences with international locations. Methods To determine serotype distribution at Madigan, we obtained GBS isolates from standard-of-care anogenital swabs from 207 women of indeterminate gravidity between ages 18-40 during a five month interval. Serotype was determined using a recently described molecular method of polymerase chain reaction by capsular polysaccharide synthesis (cps) genes associated with pathogen virulence. Results Serotypes Ia, III, and V were the most prevalent (28%, 27%, and 17%, respectively). A systematic review of global GBS seroprevalence, meta-analysis, and statistical comparison revealed strikingly similar serodistibution at Madigan relative to civilian-sector populations in Canada and the United States. Serotype Ia was the only serotype consistently higher in North American populations relative to other geographic regions (p < 0.005). The number of non-typeable isolates was significantly lower in the study (p < 0.005). Conclusion This study establishes PCR-based serotyping as a viable strategy for GBS epidemiological surveillance. Our results suggest that GBS seroprevalence remains stable in North America over the past two decades. PMID:21106080

Molecular analysis of a novel Toll/interleukin-1 receptor (TIR)-domain containing virulence protein of Y. pseudotuberculosis among Far East scarlet-like fever serotype I strains.

PubMed

Nörenberg, Dominik; Wieser, Andreas; Magistro, Giuseppe; Hoffmann, Christiane; Meyer, Christian; Messerer, Maxim; Schubert, Sören

2013-12-01

Pathogenicity of Yersinia pseudotuberculosis is determined by an arsenal of virulence factors. Particularly, the Yersinia outer proteins (Yops) and the Type III secretion system (T3SS) encoded on the pYV virulence plasmid are required for Yersinia pathogenicity. A specific group of Y. pseudotuberculosis, responsible for the clinical syndrome described as Far East scarlet-like fever (FESLF), is known to have an altered virulence gene cluster. Far East strains cause unique clinical symptoms for which the pYV virulence plasmid plays apparently a rather secondary role. Here, we characterize a previously unknown protein of Y. pseudotuberculosis serotype I strains (TcpYI) which can be found particularly among the FESLF strain group. The TcpYI protein shares considerable sequence homology to members of the Toll/IL-1 receptor family. Bacterial TIR domain containing proteins (Tcps) interact with the innate immune system by TIR-TIR interactions and subvert host defenses via individual, multifaceted mechanisms. In terms of virulence, it appears that the TcpYI protein of Y. pseudotuberculosis displays its own virulence phenotype compared to the previously characterized bacterial Tcps. Our results clearly demonstrate that TcpYI increases the intracellular survival of the respective strains in vitro. Furthermore, we show here that the intracellular survival benefit of the wild-type strain correlates with an increase in tcpYI gene expression inside murine macrophages. In support of this, we found that TcpYI enhances the survival inside the spleens of mice in a mouse model of peritonitis. Our results may point toward involvement of the TcpYI protein in inhibition of phagocytosis, particularly in distinct Y. pseudotuberculosis strains of the FESLF strain group where the pYV virulence plasmid is absent. Copyright © 2013 Elsevier GmbH. All rights reserved.

Rapid and efficient differentiation of Yersinia species using high-resolution melting analysis.

PubMed

Souza, Roberto A; Frazão, Miliane R; Almeida, Alzira M P; Falcão, Juliana P

2015-08-01

The primary goal of clinical microbiology is the accurate identification of the causative agent of the disease. Here, we describe a method for differentiation between Yersinia species using PCR-HRMA. The results revealed species-specific melting profiles. The herein developed assay can be used as an effective method to differentiate Yersinia species. Copyright © 2015 Elsevier B.V. All rights reserved.

Synergistic growth studies of Entamoeba gingivalis using an Ecologen.

PubMed

Gannon, J T; Linke, H A

1992-11-01

A unique multiple diffusion growth chamber, an Ecologen, designed for the study of interactions among microorganisms, was introduced as a means of growing xenic cultures of Entamoeba gingivalis with Crithidia sp. or Yersinia enterocolitica. Entamoeba gingivalis was grown in the central diffusion reservoir of the Ecologen connected to separate growth chambers inoculated with the microorganisms to be evaluated. Growth of the accompanying bacteria in the E. gingivalis compartment was almost completely eliminated, except for sparse Pseudomonas sp. growth. The most vital E. gingivalis cultures were observed when either Crithidia sp. or Y. enterocolitica were added to the Ecologen 48 h prior to the E. gingivalis inoculum. The medium which provided the best growth of the oral protozoan in this system was the new improved E. gingivalis medium containing antibiotics.

Genetic and metabolic signals during acute enteric bacterial infection alter the microbiota and drive progression to chronic inflammatory disease

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kamdar, Karishma; Khakpour, Samira; Chen, Jingyu

Chronic inflammatory disorders are thought to arise due to an interplay between predisposing host genetics and environmental factors. For example, the onset of inflammatory bowel disease is associated with enteric proteobacterial infection, yet the mechanistic basis for this association is unclear. We have shown previously that genetic defiency in TLR1 promotes acute enteric infection by the proteobacteria Yersinia enterocolitica. Examining that model further, we uncovered an altered cellular immune response that promotes the recruitment of neutrophils which in turn increases metabolism of the respiratory electron acceptor tetrathionate by Yersinia. These events drive permanent alterations in anti-commensal immunity, microbiota composition, andmore » chronic inflammation, which persist long after Yersinia clearence. Deletion of the bacterial genes involved in tetrathionate respiration or treatment using targeted probiotics could prevent microbiota alterations and inflammation. Thus, acute infection can drive long term immune and microbiota alterations leading to chronic inflammatory disease in genetically predisposed individuals.« less

Rapid Multiplex Assay for Serotyping Pneumococci with Monoclonal and Polyclonal Antibodies

PubMed Central

Yu, Jigui; Lin, Jisheng; Benjamin, William H.; Waites, Ken B.; Lee, Che-hung; Nahm, Moon H.

2005-01-01

We have developed and characterized a rapid semiautomated pneumococcal serotyping system incorporating a pneumococcal lysate preparation protocol and a multiplex serotyping assay. The lysate preparation incorporates a bile solubility test to confirm pneumococcal identification that also enhances assay specificity. The multiplex serotyping assay consists of 24 assays specific for 36 serotypes: serotypes 1, 2, 3, 4, 5, 6A, 6B, 7A/7F, 8, 9L/9N, 9V, 10A/10B/39/(33C), 11A/11D/11F, 12A/12B/12F, 14, 15B/(15C), 17F, 18C, 19A, 19F, 20, 22A/22F, 23F, and 33A/33F. The multiplex assay requires a flow cytometer, two sets of latex particles coated with pneumococcal polysaccharides, and serotype-specific antibodies. Fourteen newly developed monoclonal antibodies specific for common serotypes and a pool of polyclonal rabbit sera for some of the less-common serotypes are used. The two monoclonal antibodies specific for serotypes 18C and 23F recognize serotype-specific epitopes that have not been previously described. These monoclonal antibodies make the identification of the 14 common serotypes invariant. The specificity of the serotyping assay is fully characterized with pneumococci of all known (i.e., 90) serotypes. The assay is sensitive enough to use bacterial lysates diluted 20 fold. Our serotyping system can identify not only all the serotypes in pneumococcal vaccines but also most (>90%) of clinical isolates. This system should be very useful in serotyping clinical isolates for evaluating pneumococcal vaccine efficacy. PMID:15634965

Intelligent Adversary Risk Analysis: A Bioterrorism Risk Management Model (PREPRINT)

DTIC Science & Technology

2009-02-20

Dengue • Listeria monocytogenes • Filoviruses coronavirus ( SARS -CoV) • Campylobacter jejuni • Ebola • Yersinia enterocolitica) • Marburg...OF: 17. LIMITATION OF ABSTRACT Same as Report ( SAR ) 18. NUMBER OF PAGES 29 19a. NAME OF RESPONSIBLE PERSON a. REPORT unclassified b. ABSTRACT...which may be to maximize the consequences they can inflict (Golany et al., Figure 2: Decision Tree Example  7    Submitted to Risk Analysis

Yersinia-flea interactions and the evolution of the arthropod-borne transmission route of plague

PubMed Central

Chouikha, Iman; Hinnebusch, B. Joseph

2012-01-01

Yersinia pestis, the causative agent of plague, is unique among the enteric group of Gram-negative bacteria in relying on a blood-feeding insect for transmission. The Yersinia-flea interactions that enable plague transmission cycles have had profound historical consequences as manifested by human plague pandemics. The arthropod-borne transmission route was a radical ecologic change from the food- and water-borne transmission route of Yersinia pseudotuberculosis, from which Y. pestis diverged only within the last 20,000 years. Thus, the interactions of Y. pestis with its flea vector that lead to colonization and successful transmission are the result of a recent evolutionary adaptation that required relatively few genetic changes. These changes from the Y. pseudotuberculosis progenitor included loss of insecticidal activity, increased resistance to antibacterial factors in the flea midgut, and extending Yersinia biofilm-forming ability to the flea host environment. PMID:22406208

Serotypes in Saccharomyces telluris: Their relation to source of isolation

USGS Publications Warehouse

Hasenclever, H.F.; Kocan, R.M.

1973-01-01

Three serotypes have been characterized with three reference strains of Saccharomyces telluris and designated as A, B, and C. One reference strain of Torpulopsis bovina, the imperfect form of S. telluris, belonged to serotype B. Strains of S. telluris isolated from four columbid species were serotyped. All 98 strains of this yeast isolated from Columba livia belonged to serotype B. Three other columbid species, C. leucocephala, C. fasciata, and Zenaidura macroura harbored strains of serotype C only. Serotype A was not isolated from any of the avian species.

Sequetyping: Serotyping Streptococcus pneumoniae by a Single PCR Sequencing Strategy

PubMed Central

Leung, Marcus H.; Bryson, Kevin; Freystatter, Kathrin; Pichon, Bruno; Edwards, Giles; Gillespie, Stephen H.

2012-01-01

The introduction of pneumococcal conjugate vaccines necessitates continued monitoring of circulating strains to assess vaccine efficacy and replacement serotypes. Conventional serological methods are costly, labor-intensive, and prone to misidentification, while current DNA-based methods have limited serotype coverage requiring multiple PCR primers. In this study, a computer algorithm was developed to interrogate the capsulation locus (cps) of vaccine serotypes to locate primer pairs in conserved regions that border variable regions and could differentiate between serotypes. In silico analysis of cps from 92 serotypes indicated that a primer pair spanning the regulatory gene cpsB could putatively amplify 84 serotypes and differentiate 46. This primer set was specific to Streptococcus pneumoniae, with no amplification observed for other species, including S. mitis, S. oralis, and S. pseudopneumoniae. One hundred thirty-eight pneumococcal strains covering 48 serotypes were tested. Of 23 vaccine serotypes included in the study, most (19/22, 86%) were identified correctly at least to the serogroup level, including all of the 13-valent conjugate vaccine and other replacement serotypes. Reproducibility was demonstrated by the correct sequetyping of different strains of a serotype. This novel sequence-based method employing a single PCR primer pair is cost-effective and simple. Furthermore, it has the potential to identify new serotypes that may evolve in the future. PMID:22553238

Antigen analyses of serotypes of streptococcus mutans using a monoclonal antibody elaborated against serotype g polysaccharide antigen.

PubMed

Okahashi, N; Nishida, Y; Futakami, K; Hamada, S

1985-04-01

A hybridoma (F4B) which produced a monoclonal antibody (mAb) specific for serotype g carbohydrate antigen (RRg) of Streptococcus mutans 6715 was obtained. The F4B mAb cross-reacted with purified carbohydrate antigens of serotype d (RRd) and serotype h (TCAh). In immunodiffusion tests, F4B mAb produced a stable precipitin band with RRg, while the band developed between the mAb and RRd/TCAh in the cold disappeared when incubated at room temperature. The immunoprecipitin reaction between F4B mAb and RRg was strongly inhibited upon addition of lactose.

Serotypic characterization of rotaviruses derived from asymptomatic human neonatal infections.

PubMed Central

Hoshino, Y; Wyatt, R G; Flores, J; Midthun, K; Kapikian, A Z

1985-01-01

Nineteen rotavirus strains derived from asymptomatic neonates (seven from England, five from Australia, two from Venezuela, and five from Sweden) were successfully cultivated in primary African green monkey kidney cell cultures, serotyped by plaque reduction neutralization tests, subgrouped by indirect enzyme-linked immunosorbent assay, and electropherotyped by polyacrylamide gel electrophoresis. All 19 strains were shown to fall into one of the four known human serotypes; serotype 1 (all Venezuelan strains), serotype 2 (all Swedish strains), serotype 3 (all Australian strains), or serotype 4 (all English strains). Hyperimmune guinea pig serum raised against the Venezuelan strain (M37) neutralized not only serotype 1 (strain Wa) but also serotype 4 (strain St. Thomas no. 3) viruses to a similar degree. The English, Australian, and Venezuelan isolates were found to belong to subgroup 2, and the Swedish strains were subgroup 1 viruses. The potential importance of these rotaviruses obtained from neonates as possible vaccine candidates is discussed. Images PMID:2984247

Simultaneous Rapid Detection and Serotyping of Cronobacter sakazakii Serotypes O1, O2, and O3 by Using Specific Monoclonal Antibodies

PubMed Central

Scharinger, Eva J.; Dietrich, Richard; Kleinsteuber, Ina; Märtlbauer, Erwin

2016-01-01

Cronobacter sakazakii is a foodborne pathogen associated with rare but often lethal infections in neonates. Powdered infant formula (PIF) represents the most frequent source of infection. Out of the identified serotypes (O1 to O7), O1, O2, and O3 are often isolated from clinical and PIF samples. Serotype-specific monoclonal antibodies (MAbs) suitable for application in enzyme immunoassays (EIAs) for the rapid detection of C. sakazakii have not yet been developed. In this study, we created specific MAbs with the ability to bind to C. sakazakii of serotypes O1, O2, and O3. Characterization by indirect EIAs, immunofluorescence, motility assays, and immunoblotting identified lipopolysaccharide (LPS) and exopolysaccharide (EPS) as the antigenic determinants of the MAbs. The established sandwich EIAs were highly sensitive and were able to detect between 2 × 103 and 9 × 106 CFU/ml. Inclusivity tests confirmed that 93% of serotype O1 strains, 100% of O2 strains, and 87% of O3 strains were detected at low cell counts. No cross-reactivity with >100 strains of Cronobacter spp. and other Enterobacteriaceae was observed, except for that with C. sakazakii serotype O3 and Cronobacter muytjensii serotype O1. Moreover, the sandwich EIAs detected C. sakazakii in PIF samples artificially contaminated with 1 to 10 bacterial cells per 10 g of sample after 15 h of preenrichment. The use of these serotype-specific MAbs not only allows the reliable detection of C. sakazakii strains but also enables simultaneous serotyping in a simple sandwich EIA method. PMID:26850303

Population structure of the Yersinia pseudotuberculosis complex according to multilocus sequence typing

PubMed Central

Laukkanen-Ninios, Riikka; Didelot, Xavier; Jolley, Keith A.; Morelli, Giovanna; Sangal, Vartul; Kristo, Paula; Imori, Priscilla F. M.; Fukushima, Hiroshi; Siitonen, Anja; Tseneva, Galina; Voskressenskaya, Ekaterina; Falcao, Juliana P.; Korkeala, Hannu; Maiden, Martin C. J.; Mazzoni, Camila; Carniel, Elisabeth; Skurnik, Mikael; Achtman, Mark

2014-01-01

Summary Multilocus sequence analysis of 417 strains of Yersinia pseudotuberculosis revealed that it is a complex of four populations, three of which have been previously assigned species status [Y. pseudotuberculosis sensu stricto (s.s.), Yersinia pestis and Yersinia similis] and a fourth population, which we refer to as the Korean group, which may be in the process of speciation. We detected clear signs of recombination within Y. pseudotuberculosis s.s. as well as imports from Y. similis and the Korean group. The sources of genetic diversification within Y. pseudotuberculosis s.s. were approximately equally divided between recombination and mutation, whereas recombination has not yet been demonstrated in Y. pestis, which is also much more genetically monomorphic than is Y. pseudotuberculosis s.s. Most Y. pseudotuberculosis s.s. belong to a diffuse group of sequence types lacking clear population structure, although this species contains a melibiose-negative clade that is present globally in domesticated animals. Yersinia similis corresponds to the previously identified Y. pseudotuberculosis genetic type G4, which is probably not pathogenic because it lacks the virulence factors that are typical for Y. pseudotuberculosis s.s. In contrast, Y. pseudotuberculosis s.s., the Korean group and Y. pestis can all cause disease in humans. PMID:21951486

Distribution and Evolution of Yersinia Leucine-Rich Repeat Proteins

PubMed Central

Hu, Yueming; Huang, He; Hui, Xinjie; Cheng, Xi; White, Aaron P.

2016-01-01

Leucine-rich repeat (LRR) proteins are widely distributed in bacteria, playing important roles in various protein-protein interaction processes. In Yersinia, the well-characterized type III secreted effector YopM also belongs to the LRR protein family and is encoded by virulence plasmids. However, little has been known about other LRR members encoded by Yersinia genomes or their evolution. In this study, the Yersinia LRR proteins were comprehensively screened, categorized, and compared. The LRR proteins encoded by chromosomes (LRR1 proteins) appeared to be more similar to each other and different from those encoded by plasmids (LRR2 proteins) with regard to repeat-unit length, amino acid composition profile, and gene expression regulation circuits. LRR1 proteins were also different from LRR2 proteins in that the LRR1 proteins contained an E3 ligase domain (NEL domain) in the C-terminal region or an NEL domain-encoding nucleotide relic in flanking genomic sequences. The LRR1 protein-encoding genes (LRR1 genes) varied dramatically and were categorized into 4 subgroups (a to d), with the LRR1a to -c genes evolving from the same ancestor and LRR1d genes evolving from another ancestor. The consensus and ancestor repeat-unit sequences were inferred for different LRR1 protein subgroups by use of a maximum parsimony modeling strategy. Structural modeling disclosed very similar repeat-unit structures between LRR1 and LRR2 proteins despite the different unit lengths and amino acid compositions. Structural constraints may serve as the driving force to explain the observed mutations in the LRR regions. This study suggests that there may be functional variation and lays the foundation for future experiments investigating the functions of the chromosomally encoded LRR proteins of Yersinia. PMID:27217422

Flagellar regulation in Yersinia ruckeri during infection

USDA-ARS?s Scientific Manuscript database

The gram-negative Enterobacterium Yersinia ruckeri is the etiologic agent of enteric redmouth disease (ERM), a septicemia affecting primarily farmed rainbow trout (Oncorhynchus mykiss, Walbaum). Over the past decade, there has been an increase in the prevalence of non-motile variants of Y. ruckeri a...

Definition of human rotavirus serotypes by plaque reduction assay.

PubMed Central

Wyatt, R G; Greenberg, H B; James, W D; Pittman, A L; Kalica, A R; Flores, J; Chanock, R M; Kapikian, A Z

1982-01-01

Twenty different human rotavirus reassortants were characterized serologically by a plaque reduction assay as belonging to one of three distinct serotypes. Fourteen were similar if not identical to our prototype Wa strain; two were like the prototype DS-1 strain, and four belonged to a third serotype for which a prototype has not yet been selected. Hyperimmune sera raised against the three serotypes were required to distinguish among them, since postinfection sera had lower titers and were more cross-reactive than hyperimmune sera. These results confirmed the ability of a qualitative cytopathic neutralization test to predict correctly the Wa or DS-1 serotype. A strain of rhesus rotavirus (MMU 18006) was identified as belonging to the newly defined third serotype. Finally, an attempt was made to correlate previously published serotype analysis by neutralization of fluorescent cell-forming units with the results determined by the plaque reduction neutralization assay. PMID:6286487

Crystal structure of the Yersinia type III secretion protein YscE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Phan, Jason; Austin, Brian P.; Waugh, David S.

2010-12-06

The plague-causing bacterium Yersinia pestis utilizes a contact-dependent (type III) secretion system (T3SS) to transport virulence factors from the bacterial cytosol directly into the interior of mammalian cells where they interfere with signal transduction pathways that mediate phagocytosis and the inflammatory response. The type III secretion apparatus is composed of 20-25 different Yersinia secretion (Ysc) proteins. We report here the structure of YscE, the smallest Ysc protein, which is a dimer in solution. The probable mode of oligomerization is discussed.

Induction of Broad-Spectrum Protective Immunity against Disparate Cryptococcus Serotypes

PubMed Central

Van Dyke, Marley C. Caballero; Chaturvedi, Ashok K.; Hardison, Sarah E.; Leopold Wager, Chrissy M.; Castro-Lopez, Natalia; Hole, Camaron R.; Wozniak, Karen L.; Wormley, Floyd L.

2017-01-01

Cryptococcosis is a fungal disease caused by multiple Cryptococcus serotypes; particularly C. neoformans (serotypes A and D) and C. gattii (serotypes B and C). To date, there is no clinically available vaccine to prevent cryptococcosis. Mice given an experimental pulmonary vaccination with a C. neoformans serotype A strain engineered to produce interferon-γ, denoted H99γ, are protected against a subsequent otherwise lethal experimental infection with C. neoformans serotype A. Thus, we determined the efficacy of immunization with C. neoformans strain H99γ to elicit broad-spectrum protection in BALB/c mice against multiple disparate Cryptococcus serotypes. We observed significantly increased survival rates and significantly decreased pulmonary fungal burden in H99γ immunized mice challenged with Cryptococcus serotypes A, B, or D compared to heat-killed H99γ (HKH99γ) immunized mice. Results indicated that prolonged protection against Cryptococcus serotypes B or D in H99γ immunized mice was CD4+ T cell dependent and associated with the induction of predominantly Th1-type cytokine responses. Interestingly, immunization with H99γ did not elicit greater protection against challenge with the Cryptococcus serotype C tested either due to low overall virulence of this strain or enhanced capacity of this strain to evade host immunity. Altogether, these studies provide “proof-of-concept” for the development of a cryptococcal vaccine that provides cross-protection against multiple disparate serotypes of Cryptococcus. PMID:29163469

Simultaneous Rapid Detection and Serotyping of Cronobacter sakazakii Serotypes O1, O2, and O3 by Using Specific Monoclonal Antibodies.

PubMed

Scharinger, Eva J; Dietrich, Richard; Kleinsteuber, Ina; Märtlbauer, Erwin; Schauer, Kristina

2016-04-01

Cronobacter sakazakii is a foodborne pathogen associated with rare but often lethal infections in neonates. Powdered infant formula (PIF) represents the most frequent source of infection. Out of the identified serotypes (O1 to O7), O1, O2, and O3 are often isolated from clinical and PIF samples. Serotype-specific monoclonal antibodies (MAbs) suitable for application in enzyme immunoassays (EIAs) for the rapid detection of C. sakazakii have not yet been developed. In this study, we created specific MAbs with the ability to bind toC. sakazakii of serotypes O1, O2, and O3. Characterization by indirect EIAs, immunofluorescence, motility assays, and immunoblotting identified lipopolysaccharide (LPS) and exopolysaccharide (EPS) as the antigenic determinants of the MAbs. The established sandwich EIAs were highly sensitive and were able to detect between 2 × 10(3)and 9 × 10(6)CFU/ml. Inclusivity tests confirmed that 93% of serotype O1 strains, 100% of O2 strains, and 87% of O3 strains were detected at low cell counts. No cross-reactivity with >100 strains of Cronobacter spp. and other Enterobacter iaceae was observed, except for that with C. sakazakii serotype O3 and Cronobacter muytjensii serotype O1. Moreover, the sandwich EIAs detected C. sakazakii in PIF samples artificially contaminated with 1 to 10 bacterial cells per 10 g of sample after 15 h of preenrichment. The use of these serotype-specific MAbs not only allows the reliable detection of C. sakazakii strains but also enables simultaneous serotyping in a simple sandwich EIA method. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Dual Infection with Bluetongue Virus Serotypes and First-Time Isolation of Serotype 5 in India.

PubMed

Hemadri, D; Maan, S; Chanda, M M; Rao, P P; Putty, K; Krishnajyothi, Y; Reddy, G H; Kumar, V; Batra, K; Reddy, Y V; Maan, N S; Reddy, Y N; Singh, K P; Shivachandra, S B; Hegde, N R; Rahman, H; Mertens, P P C

2017-12-01

Bluetongue is endemic in India and has been reported from most Indian states. Of late, the clinical disease is most frequently seen in the states of Andhra Pradesh, Telangana (erstwhile Andhra Pradesh state), Tamil Nadu and Karnataka. Our analysis of diagnostic samples from bluetongue outbreaks during 2010-2011 from the state of Karnataka identified bluetongue virus (BTV) serotype 5 (BTV-5) for the first time in India. One of the diagnostic samples (CH1) and subsequent virus isolate (IND2010/02) contained both BTV-2 and BTV-5. Segment 2 (seg-2) sequence data (400 bp: nucleotides 2538-2921) for IND2010/02-BTV5, showed 94.3% nucleotide identity to BTV-5 from South Africa (Accession no. AJ585126), confirming the virus serotype and also indicating that Seg-2 was derived from a Western topotype, which is in contrast to serotype 2, that belongs to an Eastern topotype. BTV-5 has been recently reported from Africa, China, French islands and the Americas. Although the exact source of the Indian BTV-5 isolate is still to be confirmed, recent identification of additional exotic serotypes in India is of real concern and might add to the severity of the disease seen in these outbreaks. © 2016 Blackwell Verlag GmbH.

Pasteurella multocida serotype 1 isolated from a lesser snow goose

USGS Publications Warehouse

Samuel, M.D.; Goldberg, Diana R.; Shadduck, D.J.; Price, J.I.; Cooch, E.G.

1997-01-01

Pharyngeal swabs were collected from 298 lesser snow geese (Chen caerulescens caerulescens) at Banks Island (Northwest Territories. Canada) in the summer of 1994. Pasteurella multocida serotype 1 was isolated from an adult male bird and P. multocida serotype 3 was isolated from an adult female goose. Pathogenicity of the serotype 1 isolate was confirmed by inoculation in Pekin ducks (Anas platyrhynchos). The serotype 3 isolate was non-pathogenic in Pekin ducks. This is the first documented isolation of pathogenic P. multocida serotype 1 from apparently healthy wild snow geese.

Protein antigen in serotype k Streptococcus mutans clinical isolates.

PubMed

Nakano, K; Nomura, R; Nemoto, H; Lapirattanakul, J; Taniguchi, N; Grönroos, L; Alaluusua, S; Ooshima, T

2008-10-01

Streptococcus mutans, a major pathogen of dental caries and infective endocarditis, is classified into serotypes c, e, f, and k, with serotype k strains recently reported to be frequently detected in persons with infective endocarditis. Thus, we hypothesized that common properties associated with infective endocarditis are present in those strains. Fifty-six oral S. mutans strains, including 11 serotype k strains, were analyzed. Western blotting analysis revealed expression of the 3 types of glucosyltransferases in all strains, while expression of the approximately 190-kDa cell-surface protein (PA) was absent in 12 strains, among which the prevalence of serotype k (7/12) was significantly high. Furthermore, cellular hydrophobicity and phagocytosis susceptibility were lower in the group of serotype k strains. These results indicate that the absence of PA expression, low cellular hydrophobicity, and phagocytosis susceptibility are common bacterial properties associated with serotype k strains, which may be associated with virulence for infective endocarditis.

Serotype Distribution and Drug Resistance in Streptococcus pneumoniae, Palestinian Territories

PubMed Central

Kattan, Randa; Abu Rayyan, Amal; Zheiman, Inas; Idkeidek, Suzan; Baraghithi, Sabri; Rishmawi, Nabeel; Turkuman, Sultan; Abu-Diab, Afaf; Ghneim, Riyad; Zoughbi, Madeleine; Dauodi, Rula; Ghneim, Raed; Issa, Abed-El-Razeq; Siryani, Issa; Al Qas, Randa; Liddawi, Rawan; Khamash, Hatem; Kanaan, Moein; Marzouqa, Hiyam

2011-01-01

To determine antimicrobial drug resistance of Streptococcus pneumoniae serotypes, we analyzed isolates from blood cultures of sick children residing in the West Bank before initiation of pneumococcal vaccination. Of 120 serotypes isolated, 50.8%, 73.3%, and 80.8% of the bacteremia cases could have been prevented by pneumococcal conjugate vaccines. Serotype 14 was the most drug-resistant serotype isolated. PMID:21192863

Main Concerns of Pathogenic Microorganisms in Meat

NASA Astrophysics Data System (ADS)

Nørrung, Birgit; Andersen, Jens Kirk; Buncic, Sava

Although various foods can serve as sources of foodborne illness, meat and meat products are important sources of human infections with a variety of foodborne pathogens, i.e. Salmonella spp., Campylobacter jejuni/coli, Yersinia enterocolitica, Verotoxigenic E. coli and, to some extent, Listeria monocytogenes. All these may be harboured in the gastrointestinal tract of food-producing animals. The most frequent chain of events leading to meat-borne illness involves food animals, which are healthy carriers of the pathogens that are subsequently transferred to humans through production, handling and consumption of meat and meat products. Occurrences of Salmonella spp., C. jejuni/coli, Y. enterocolitica and Verotoxigenic E. coli in fresh red meat vary relatively widely, although most often are between 1 and 10%, depending on a range of factors including the organism, geographical factors, farming and/or meat production practices.

Salmonella serotypes in reptiles and humans, French Guiana.

PubMed

Gay, Noellie; Le Hello, Simon; Weill, François-Xavier; de Thoisy, Benoit; Berger, Franck

2014-05-14

In French Guiana, a French overseas territory located in the South American northern coast, nearly 50% of Salmonella serotypes isolated from human infections belong to serotypes rarely encountered in metropolitan France. A reptilian source of contamination has been investigated. Between April and June 2011, in the area around Cayenne, 151 reptiles were collected: 38 lizards, 37 snakes, 32 turtles, 23 green iguanas and 21 caimans. Cloacal swab samples were collected and cultured. Isolated Salmonella strains were identified biochemically and serotyped. The overall carriage frequency of carriage was 23.2% (95% confidence interval: 16.7-30.4) with 23 serotyped strains. The frequency of Salmonella carriage was significantly higher for wild reptiles. Near two-thirds of the Salmonella serotypes isolated from reptiles were also isolated from patients in French Guiana. Our results highlight the risk associated with the handling and consumption of reptiles and their role in the spread of Salmonella in the environment. Copyright © 2014 Elsevier B.V. All rights reserved.

Botulinum neurotoxin serotypes detected by electrochemical impedance spectroscopy.

PubMed

Savage, Alison C; Buckley, Nicholas; Halliwell, Jennifer; Gwenin, Christopher

2015-05-06

Botulinum neurotoxin is one of the deadliest biological toxins known to mankind and is able to cause the debilitating disease botulism. The rapid detection of the different serotypes of botulinum neurotoxin is essential for both diagnosis of botulism and identifying the presence of toxin in potential cases of terrorism and food contamination. The modes of action of botulinum neurotoxins are well-established in literature and differ for each serotype. The toxins are known to specifically cleave portions of the SNARE proteins SNAP-25 or VAMP; an interaction that can be monitored by electrochemical impedance spectroscopy. This study presents a SNAP-25 and a VAMP biosensors for detecting the activity of five botulinum neurotoxin serotypes (A-E) using electrochemical impedance spectroscopy. The biosensors are able to detect concentrations of toxins as low as 25 fg/mL, in a short time-frame compared with the current standard methods of detection. Both biosensors show greater specificity for their compatible serotypes compared with incompatible serotypes and denatured toxins.

Botulinum Neurotoxin Serotypes Detected by Electrochemical Impedance Spectroscopy

PubMed Central

Savage, Alison C.; Buckley, Nicholas; Halliwell, Jennifer; Gwenin, Christopher

2015-01-01

Botulinum neurotoxin is one of the deadliest biological toxins known to mankind and is able to cause the debilitating disease botulism. The rapid detection of the different serotypes of botulinum neurotoxin is essential for both diagnosis of botulism and identifying the presence of toxin in potential cases of terrorism and food contamination. The modes of action of botulinum neurotoxins are well-established in literature and differ for each serotype. The toxins are known to specifically cleave portions of the SNARE proteins SNAP-25 or VAMP; an interaction that can be monitored by electrochemical impedance spectroscopy. This study presents a SNAP-25 and a VAMP biosensors for detecting the activity of five botulinum neurotoxin serotypes (A–E) using electrochemical impedance spectroscopy. The biosensors are able to detect concentrations of toxins as low as 25 fg/mL, in a short time-frame compared with the current standard methods of detection. Both biosensors show greater specificity for their compatible serotypes compared with incompatible serotypes and denatured toxins. PMID:25954998

Serotype 3 is a common serotype causing invasive pneumococcal disease in children less than 5 years old, as identified by real-time PCR.

PubMed

Selva, L; Ciruela, P; Esteva, C; de Sevilla, M F; Codina, G; Hernandez, S; Moraga, F; García-García, J J; Planes, A; Coll, F; Jordan, I; Cardeñosa, N; Batalla, J; Salleras, L; Dominguez, A; Muñoz-Almagro, C

2012-07-01

Serotype 3 is one of the most often detected pneumococcal serotypes in adults and it is associated with serious disease. In contrast, the isolation of serotype 3 by bacterial culture is unusual in children with invasive pneumococcal disease (IPD). The purpose of this study was to learn the serotype distribution of IPD, including culture-negative episodes, by using molecular methods in normal sterile samples. We studied all children<5 years of age with IPD admitted to two paediatric hospitals in Catalonia, Spain, from 2007 to 2009. A sequential real-time polymerase chain reaction (PCR) approach was added to routine methods for the detection and serotyping of pneumococcal infection. Among 257 episodes (219 pneumonia, 27 meningitis, six bacteraemia and five others), 33.5% were identified by culture and the rest, 66.5%, were detected exclusively by real-time PCR. The most common serotypes detected by culture were serotypes 1 (26.7%) and 19A (25.6%), and by real-time PCR, serotypes 1 (19.8%) and 3 (18.1%). Theoretical coverage rates by the PCV7, PCV10 and PCV13 vaccines were 10.5, 52.3 and 87.2%, respectively, for those episodes identified by culture, compared to 5.3, 31.6 and 60.2% for those identified only by real-time PCR. Multiplex real-time PCR has been shown to be useful for surveillance studies of IPD. Serotype 3 is underdiagnosed by culture and is important in paediatric IPD.

Toxoplasma serotype is associated with development of ocular toxoplasmosis.

PubMed

Shobab, Leila; Pleyer, Uwe; Johnsen, Joerdis; Metzner, Sylvia; James, Erick R; Torun, N; Fay, Michael P; Liesenfeld, Oliver; Grigg, Michael E

2013-11-01

Worldwide, ocular toxoplasmosis (OT) is the principal cause of posterior uveitis, a severe, life-altering disease. A Toxoplasma gondii enzyme-linked immunoassay that detects strain-specific antibodies present in serum was used to correlate serotype with disease. Toxoplasma serotypes in consecutive serum samples from German uveitis patients with OT were compared with non-OT seropositive patients with noninfectious autoimmune posterior uveitis. OT patients were tested for association of parasite serotype with age, gender, location, clinical onset, size, visual acuity, or number of lesions (mean follow-up, 3.8 years) to determine association with recurrences. A novel, nonreactive (NR) serotype was detected more frequently in serum samples of OT patients (50/114, 44%) than in non-OT patients (4/56, 7%) (odds ratio, 10.0; 95% confidence interval 3.4-40.8; P < .0001). Non-OT patients were predominantly infected with Type II strains (39/56; 70%), consistent with expected frequencies in Central Europe. Among OT patients, those with NR serotypes experienced more frequent recurrences (P = .037). Polymerase chain reaction detected parasite DNA in 8/60 OT aqueous humor specimens but failed to identify Type II strain alleles. Toxoplasma NR and Type II serotypes predominate in German OT patients. The NR serotype is associated with OT recurrences, underscoring the value of screening for management of disease.

Evaluation of a rapid method to exclude the presence of certain enteric pathogens in stool specimens.

PubMed Central

Teti, G; Burdash, N M; Zamboni, C; Fava, C; Tomasello, F; Mastroeni, P

1984-01-01

A new commercial method intended to exclude the presence of Salmonella spp., Shigella spp., and Yersinia enterocolitica and to presumptively identify Salmonella isolates within 2 h after primary isolation from stool specimens was evaluated. This system is marketed in Europe as API Z and in the United States as Rapid SST. The strip consists of five pairs of cupules for the screening of five lactose-negative colonies. The first cupule of each pair detects the presence of five enzymatic activities, whereas the second serves to maintain the strain for additional testing if necessary. A total of 197 fresh isolates from stool specimens and 217 stock cultures of Salmonella spp., Shigella spp., and Yersinia enterocolitica were tested, with the API 20E system as a reference method. In the stool specimens, 77.3% of the bacteria could be excluded from further workup for the presence of these organisms within 2 h. Over 97% of the stock strains and each of three fresh Salmonella isolates tested produced a reaction pattern corresponding to a correct presumptive identification. This reaction pattern was not produced by any isolate other than the Salmonella isolates. The API Z system can be used as a screen for the presence of Salmonella and Shigella spp. and can provide an accurate presumptive identification of Salmonella isolates within 2 h after primary isolation. PMID:6394610

Serotypes of Streptococcus suis isolated from healthy pigs in Phayao Province, Thailand.

PubMed

Thongkamkoon, P; Kiatyingangsulee, T; Gottschalk, M

2017-01-19

Streptococcus suis (S. suis) is an important swine and human pathogen. There are 33 serotypes that have been described. Zoonotic cases are very common the Northern part of Thailand, especially in Phayao Province. However, the prevalence of S. suis and, more particularly the different serotypes, in pigs in this region is poorly known and needed to be addressed. Distribution of S. suis serotypes varies depending on the geographical area. Knowledge of the serotype distribution is important for epidemiological studies. Consequently, 180 tonsil samples from slaughterhouse pigs in Phayao Province had been collected for surveillance, from which 196 S. suis isolates were recovered. Each isolate was subcultured and its serotype identified using multiplex PCR. Slide agglutination combined with precipitation tests were used following multiplex PCR to differentiate the isolates showing similar sizes of amplified products specific to either serotype 1 or 14 and 2 or 1/2. Non-typable isolates by multiplex PCR were serotyped by the coagglutination test. Of the 196 isolates, 123 (62.8%) were typable and 73 (37.2%) were non-typable. This study revealed the presence of serotypes 1, 1/2, 2, 3, 4, 5, 7, 9, 11, 12, 13, 14, 21, 22, 23, 24, 25, 29, and 30. Serotype 23 was the most prevalent (20/196, 10.2%), followed by serotype 9 (16/196, 8.2%), serotype 7 (16/196, 8.2%), and serotype 2 (11/196, 5.6%). The latter is the serotype responsible for most human cases. Almost all serotypes previously described are present in Northern Thailand. Therefore, this report provides useful data for future bacteriological studies.

Lessons From Globally Coordinated Cessation of Serotype 2 Oral Poliovirus Vaccine for the Remaining Serotypes

PubMed Central

Duintjer Tebbens, Radboud J.

2017-01-01

Abstract Background. Comparing model expectations with the experience of oral poliovirus vaccine (OPV) containing serotype 2 (OPV2) cessation can inform risk management for the expected cessation of OPV containing serotypes 1 and 3 (OPV13). Methods. We compare the expected post-OPV2-cessation OPV2-related viruses from models with the evidence available approximately 6 months after OPV2 cessation. We also model the trade-offs of use vs nonuse of monovalent OPV (mOPV) for outbreak response considering all 3 serotypes. Results. Although too early to tell definitively, the observed die-out of OPV2-related viruses in populations that attained sufficiently intense trivalent OPV (tOPV) use prior to OPV2 cessation appears consistent with model expectations. As expected, populations that did not intensify tOPV use prior to OPV2 cessation show continued circulation of serotype 2 vaccine-derived polioviruses (VDPVs). Failure to aggressively use mOPV to respond to circulating VDPVs results in a high risk of uncontrolled outbreaks that would require restarting OPV. Conclusions. Ensuring a successful endgame requires more aggressive OPV cessation risk management than has occurred to date for OPV2 cessation. This includes maintaining high population immunity to transmission up until OPV13 cessation, meeting all prerequisites for OPV cessation, and ensuring sufficient vaccine supply to prevent and respond to outbreaks. PMID:28838198

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tew, Karen

I spent the last ten weeks working in the Systems Biology department at Sandia National Laboratories in Livermore, CA. Under the direction of Zachary Bent, I helped do preliminary testing/optimization of a vacuum-driven, capture-based system for pathogen RNA transcript enrichment. I also worked on a project to create mutant Yersinia enterocolitica strains in order to test which genes are involved in intracellular pathogen virulence, as well as sequencing several Klebsiella pneumoniae samples for use by a bioinformaticist.

Toxoplasma Serotype Is Associated With Development of Ocular Toxoplasmosis

PubMed Central

Shobab, Leila; Pleyer, Uwe; Johnsen, Joerdis; Metzner, Sylvia; James, Erick R.; Torun, N.; Fay, Michael P.; Liesenfeld, Oliver; Grigg, Michael E.

2013-01-01

Background. Worldwide, ocular toxoplasmosis (OT) is the principal cause of posterior uveitis, a severe, life-altering disease. A Toxoplasma gondii enzyme-linked immunoassay that detects strain-specific antibodies present in serum was used to correlate serotype with disease. Methods. Toxoplasma serotypes in consecutive serum samples from German uveitis patients with OT were compared with non-OT seropositive patients with noninfectious autoimmune posterior uveitis. OT patients were tested for association of parasite serotype with age, gender, location, clinical onset, size, visual acuity, or number of lesions (mean follow-up, 3.8 years) to determine association with recurrences. Results. A novel, nonreactive (NR) serotype was detected more frequently in serum samples of OT patients (50/114, 44%) than in non-OT patients (4/56, 7%) (odds ratio, 10.0; 95% confidence interval 3.4–40.8; P < .0001). Non-OT patients were predominantly infected with Type II strains (39/56; 70%), consistent with expected frequencies in Central Europe. Among OT patients, those with NR serotypes experienced more frequent recurrences (P = .037). Polymerase chain reaction detected parasite DNA in 8/60 OT aqueous humor specimens but failed to identify Type II strain alleles. Conclusions. Toxoplasma NR and Type II serotypes predominate in German OT patients. The NR serotype is associated with OT recurrences, underscoring the value of screening for management of disease. PMID:23878321

Molecular diagnosis of non-serotypeable Shigella spp.: problems and prospects.

PubMed

Muthuirulandi Sethuvel, Dhiviya Prabaa; Devanga Ragupathi, Naveen Kumar; Anandan, Shalini; Walia, Kamini; Veeraraghavan, Balaji

2017-02-01

It is not always possible to identify Shigella serogroups/serotypes by biochemical properties alone. Specific identification requires serotyping. Occasionally, isolates that resemble Shigella spp. biochemically, but are non-agglutinable with available antisera, have been observed. Several mechanisms have been reported to limit the efficiency of the serotyping assay. Serotype conversion is a major mechanism in Shigella spp. to escape protective host immune responses. This easy conversion through significant modification of the O-antigen backbone results in different serotypes, which makes laboratory identification difficult. Furthermore, members of the family Enterobacteriaceae are closely related and there is antigenic cross-over (intra- and inter-specific cross-reaction) which affects the agglutination reaction. The performance of the available methods for identification of non-serotypeable Shigella is discussed here, and reveals them to be non-reliable. This shows a need for an alternative method for identification and typing of Shigella spp.

The Pneumococcal Serotype 15C Capsule Is Partially O-Acetylated and Allows for Limited Evasion of 23-Valent Pneumococcal Polysaccharide Vaccine-Elicited Anti-Serotype 15B Antibodies

PubMed Central

Spencer, Brady L.; Shenoy, Anukul T.; Orihuela, Carlos J.

2017-01-01

ABSTRACT As a species, Streptococcus pneumoniae (the pneumococcus) utilizes a diverse array of capsular polysaccharides to evade the host. In contrast to large variations in sugar composition and linkage formation, O-acetylation is a subtle capsular modification that nonetheless has a large impact on capsular shielding and recognition of the capsule by vaccine-elicited antibodies. Serotype 15B, which is included in the 23-valent pneumococcal polysaccharide vaccine (PPV23), carries the putative O-acetyltransferase gene wciZ. The coding sequence of wciZ contains eight consecutive TA repeats [(TA)8]. Replication slippage is thought to result in the addition or loss of TA repeats, subsequently causing frameshift and truncation of WciZ to yield a nonacetylated serotype, 15C. Using sensitive serological tools, we show that serotype 15C isolates whose wciZ contains seven or nine TA repeats retain partial O-acetylation, while serotype 15C isolates whose wciZ contains six TA repeats have barely detectable O-acetylation. We confirmed by inhibition enzyme-linked immunosorbent assay that (TA)7 serotype 15C is ∼0.1% as acetylated as serotype 15B, while serotype 15X is nonacetylated. To eliminate the impact of genetic background, we created isogenic serotype 15B, (TA)7 serotype 15C, and 15BΔwciZ (15X) strains and found that reduction or absence of WciZ-mediated O-acetylation did not affect capsular shielding from phagocytes, biofilm formation, adhesion to nasopharyngeal cells, desiccation tolerance, or murine colonization. Sera from PPV23-immunized persons opsonized serotype 15B significantly but only slightly better than serotypes 15C and 15X; thus, PPV23 may not result in expansion of serotype 15C. PMID:28637806

The Pneumococcal Serotype 15C Capsule Is Partially O-Acetylated and Allows for Limited Evasion of 23-Valent Pneumococcal Polysaccharide Vaccine-Elicited Anti-Serotype 15B Antibodies.

PubMed

Spencer, Brady L; Shenoy, Anukul T; Orihuela, Carlos J; Nahm, Moon H

2017-08-01

As a species, Streptococcus pneumoniae (the pneumococcus) utilizes a diverse array of capsular polysaccharides to evade the host. In contrast to large variations in sugar composition and linkage formation, O-acetylation is a subtle capsular modification that nonetheless has a large impact on capsular shielding and recognition of the capsule by vaccine-elicited antibodies. Serotype 15B, which is included in the 23-valent pneumococcal polysaccharide vaccine (PPV23), carries the putative O-acetyltransferase gene wciZ The coding sequence of wciZ contains eight consecutive TA repeats [(TA) 8 ]. Replication slippage is thought to result in the addition or loss of TA repeats, subsequently causing frameshift and truncation of WciZ to yield a nonacetylated serotype, 15C. Using sensitive serological tools, we show that serotype 15C isolates whose wciZ contains seven or nine TA repeats retain partial O-acetylation, while serotype 15C isolates whose wciZ contains six TA repeats have barely detectable O-acetylation. We confirmed by inhibition enzyme-linked immunosorbent assay that (TA) 7 serotype 15C is ∼0.1% as acetylated as serotype 15B, while serotype 15X is nonacetylated. To eliminate the impact of genetic background, we created isogenic serotype 15B, (TA) 7 serotype 15C, and 15BΔ wciZ (15X) strains and found that reduction or absence of WciZ-mediated O-acetylation did not affect capsular shielding from phagocytes, biofilm formation, adhesion to nasopharyngeal cells, desiccation tolerance, or murine colonization. Sera from PPV23-immunized persons opsonized serotype 15B significantly but only slightly better than serotypes 15C and 15X; thus, PPV23 may not result in expansion of serotype 15C. Copyright © 2017 American Society for Microbiology.

Isolation of serotype-specific antibodies against dengue virus non-structural protein 1 using phage display and application in a multiplexed serotyping assay.

PubMed

Lebani, Kebaneilwe; Jones, Martina L; Watterson, Daniel; Ranzoni, Andrea; Traves, Renee J; Young, Paul R; Mahler, Stephen M

2017-01-01

The multidimensional nature of dengue virus (DENV) infections, which can be caused by four distinct serotypes of the virus, complicates the sensitivity of assays designed for the diagnosis of infection. Different viral markers can be optimally detected at different stages of infection. Of particular clinical importance is the early identification of infection, which is pivotal for disease management and the development of blood screening assays. Non-structural protein 1 (NS1) is an early surrogate marker of infection and its detection in serum coincides with detectable viraemia. The aim of this work was to isolate and characterise serotype-specific monoclonal antibodies that bind to NS1 for each of the four DENV serotypes. This was achieved using phage display and a subtractive biopanning strategy to direct the antibody selection towards serotype-specific epitopes. This antibody isolation strategy has advantages over immunisation techniques where it is difficult to avoid antibody responses to cross-reactive, immunodominant epitopes. Serotype specificity to recombinant antigen for each of the antibodies was confirmed by Enzyme Linked Immunosorbent Assay (ELISA) and Surface Plasmon Resonance. Confirmation of binding to native DENV NS1 was achieved using ELISA and immunofluorescence assay on DENV infected Vero cells. No cross-reactivity with Zika or Kunjin viruses was observed. A previously isolated pan-reactive antibody that binds to an immunodominant epitope was able to pair with each of the serotype-specific antibodies in a sandwich ELISA, indicating that the serotype specific antibodies bind to epitopes which are all spatially distinct from the immunodominant epitope. These antibodies were suitable for use in a multiplexed assay for simultaneous detection and serotyping of DENV NS1 in human serum. This work demonstrates that phage display coupled with novel biopanning strategies is a valuable in vitro methodology for isolation of binders that can discern amongst

Disseminated Yersinia pseudotuberculosis infection in a paca (Cuniculus paca).

PubMed

Fogelson, Susan B; Yau, Wilson; Rissi, Daniel R

2015-03-01

A 2-yr-old paca (Cuniculus paca) was presented for necropsy with a history of sudden death. GrosS examination revealed multifocal, transmural, well-demarcated, white, soft nodules scattered along the length of the small intestine. The liver also had similar nodules associated with the capsular and cut surface. Histologic evaluation of several organs, including the intestine, liver, lung, kidney, adrenal gland, and lymph nodes, was consistent with disseminated yersiniosis. In addition, aerobic bacterial culture of liver and lung tissue yielded heavy growth of Yersinia pseudotuberculosis. Yersinia pseudotuberculosis is a Gram-negative, enteric pathogen that can cause disease in a variety of terrestrial species including humans. Although systemic infection has been observed in rodent species, to our knowledge this is the first report of disseminated Y pseudotuberculosis in a paca.

Cryptococcosis Serotypes Impact Outcome and Provide Evidence of Cryptococcus neoformans Speciation.

PubMed

Desnos-Ollivier, Marie; Patel, Sweta; Raoux-Barbot, Dorothée; Heitman, Joseph; Dromer, Françoise

2015-06-09

Cryptococcus neoformans is a human opportunistic fungal pathogen causing severe disseminated meningoencephalitis, mostly in patients with cellular immune defects. This species is divided into three serotypes: A, D, and the AD hybrid. Our objectives were to compare population structures of serotype A and D clinical isolates and to assess whether infections with AD hybrids differ from infections with the other serotypes. For this purpose, we analyzed 483 isolates and the corresponding clinical data from 234 patients enrolled during the CryptoA/D study or the nationwide survey on cryptococcosis in France. Isolates were characterized in terms of ploidy, serotype, mating type, and genotype, utilizing flow cytometry, serotype- and mating type-specific PCR amplifications, and multilocus sequence typing (MLST) methods. Our results suggest that C. neoformans serotypes A and D have different routes of multiplication (primarily clonal expansion versus recombination events for serotype A and serotype D, respectively) and important genomic differences. Cryptococcosis includes a high proportion of proven or probable infections (21.5%) due to a mixture of genotypes, serotypes, and/or ploidies. Multivariate analysis showed that parameters independently associated with failure to achieve cerebrospinal fluid (CSF) sterilization by week 2 were a high serum antigen titer, the lack of flucytosine during induction therapy, and the occurrence of mixed infection, while infections caused by AD hybrids were more likely to be associated with CSF sterilization. Our study provides additional evidence for the possible speciation of C. neoformans var. neoformans and grubii and highlights the importance of careful characterization of causative isolates. Cryptococcus neoformans is an environmental fungus causing severe disease, estimated to be responsible for 600,000 deaths per year worldwide. This species is divided into serotypes A and D and an AD hybrid, and these could be considered two

PCR deduction of invasive and colonizing pneumococcal serotypes from Venezuela: a critical appraisal.

PubMed

Bello Gonzalez, Teresita; Rivera-Olivero, Ismar Alejandra; Sisco, María Carolina; Spadola, Enza; Hermans, Peter W; de Waard, Jacobus H

2014-04-15

Serotype surveillance of Streptococcus pneumoniae is indispensable for evaluating the potential impact of pneumococcal conjugate vaccines. Serotyping by the standard Quellung reaction is technically demanding, time consuming, and expensive. A simple and economical strategy is multiplex PCR-based serotyping. We evaluated the cost effectiveness of a modified serial multiplex PCR (mPCR), resolving 24 serotypes in four PCR reactions and optimally targeting the most prevalent invasive and colonizing pneumococcal serotypes found in Venezuela. A total of 223 pneumococcal isolates, 140 invasive and 83 carriage isolates, previously serotyped by the Quellung reaction and representing the 18 most common serotypes/groups identified in Venezuela, were serotyped with the adapted mPCR. The mPCR serotyped 76% of all the strains in the first two PCR reactions and 91% after four reactions, correctly identifying 17 serotypes/groups. An isolate could be serotyped with mPCR in less than 2 minutes versus 15 minutes for the Quellung reaction, considerably lowering labor costs. A restrictive weakness of mPCR was found for the detection of 19F strains. Most Venezuelan 19F strains were not typeable using the mPCR, and two 19F cps serotype variants were identified. The mPCR assay is an accurate, rapid, and economical method for the identification of the vast majority of the serotypes from Venezuela and can be used in place of the standard Quellung reaction. An exception is the identification of serotype 19F. In this setting, most 19F strains were not detectable with mPCR, demonstrating a need of serology-based quality control for PCR-based serotyping.

Update on: Shigella new serogroups/serotypes and their antimicrobial resistance.

PubMed

Muthuirulandi Sethuvel, D P; Devanga Ragupathi, N K; Anandan, S; Veeraraghavan, B

2017-01-01

Shigellosis represents a major burden of disease in developing countries. A low infectious dose allows the disease to be spread effectively. Although shigellosis is mostly a self-limiting disease, antibiotics are recommended to reduce deaths, disease symptoms and organism-shedding time. However, in India, antimicrobial resistance among the genus Shigella is more common than among any other enteric bacteria. Notably, new serotypes or subserotypes in Shigella are reported from various parts of the world. Identification of new subserotypes of Shigella spp. is becoming a major issue as these strains are nontypeable by conventional serotyping. The commercially available antisera may not cover all possible epitopes of the O lipopolysaccharide antigen of Shigella serotypes. Therefore, molecular methods which most closely approach the resolution of full serotyping are necessary to identify such strains. In addition, the knowledge of a prevalent serotype in various geographic regions may assist in formulating strategies such as the development of a vaccine to prevent infection especially when the immunity to disease is serotype specific, and to understand the disease burden caused by new Shigella serotypes. © 2016 The Society for Applied Microbiology.

Lessons From Globally Coordinated Cessation of Serotype 2 Oral Poliovirus Vaccine for the Remaining Serotypes.

PubMed

Thompson, Kimberly M; Duintjer Tebbens, Radboud J

2017-07-01

Comparing model expectations with the experience of oral poliovirus vaccine (OPV) containing serotype 2 (OPV2) cessation can inform risk management for the expected cessation of OPV containing serotypes 1 and 3 (OPV13). We compare the expected post-OPV2-cessation OPV2-related viruses from models with the evidence available approximately 6 months after OPV2 cessation. We also model the trade-offs of use vs nonuse of monovalent OPV (mOPV) for outbreak response considering all 3 serotypes. Although too early to tell definitively, the observed die-out of OPV2-related viruses in populations that attained sufficiently intense trivalent OPV (tOPV) use prior to OPV2 cessation appears consistent with model expectations. As expected, populations that did not intensify tOPV use prior to OPV2 cessation show continued circulation of serotype 2 vaccine-derived polioviruses (VDPVs). Failure to aggressively use mOPV to respond to circulating VDPVs results in a high risk of uncontrolled outbreaks that would require restarting OPV. Ensuring a successful endgame requires more aggressive OPV cessation risk management than has occurred to date for OPV2 cessation. This includes maintaining high population immunity to transmission up until OPV13 cessation, meeting all prerequisites for OPV cessation, and ensuring sufficient vaccine supply to prevent and respond to outbreaks. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America.

Inter-serotype comparison of polysaccharides produced by extracellular enzymes from Streptococcus mutans.

PubMed

Yakushiji, T; Inoue, M; Koga, T

1984-04-15

The biochemical and morphological characteristics of polysaccharides synthesized from sucrose by extracellular enzymes from D-glucose-grown Streptococcus mutans representing serotypes a-g were compared. The polysaccharides synthesized by the enzymes from serotypes a, d, and g formed visible aggregates and firmly adhered to glass surfaces, whereas those formed by the enzymes from serotypes b, c, e, and f floated homogeneously and were poorly adherent. The enzymes of serotypes a, d, and g produced large amounts of water-insoluble polysaccharides (IPs, D-glucans), and those of serotypes b, c, e, and f water-soluble polysaccharides (SPs, D-glucans and D- fructans ). As compared with the IPs of serotypes b, c, e, and f, the IPs of serotypes a, d, and g (a) contained a higher proportion of (1----3)-alpha-D-glucosidic linkages and alpha-D-(1----3,6) branch linkages; (b) showed higher susceptibility to (1----3)-alpha-D-glucanase (serotype a excepted) and lower (1----6)-alpha-D-glucanase sensitivity; (c) contained larger amounts of high-molecular-weight fractions; (d) showed higher intrinsic viscosities (serotype b excepted); and (e) had lower S. mutans cell-agglutination activities. On electron-microscope observation, the IPs of all serotypes showed two fibrillar components; a double-stranded fibril, with short, fluffy protrusions extending out of its periphery, and a fine, single-stranded fibril. Thus, the serotypes could be divided into two major groups: a, d, and g; and b, c, e, and f. No similar grouping of serotypes was indicated by the chemical and morphological properties of SPs.

Production of latex agglutination reagents for pneumococcal serotyping

PubMed Central

2013-01-01

Background The current ‘gold standard’ for serotyping pneumococci is the Quellung test. This technique is laborious and requires a certain level of training to correctly perform. Commercial pneumococcal latex agglutination serotyping reagents are available, but these are expensive. In-house production of latex agglutination reagents can be a cost-effective alternative to using commercially available reagents. This paper describes a method for the production and quality control (QC) of latex reagents, including problem solving recommendations, for pneumococcal serotyping. Results Here we describe a method for the production of latex agglutination reagents based on the passive adsorption of antibodies to latex particles. Sixty-five latex agglutination reagents were made using the PneuCarriage Project (PCP) method, of which 35 passed QC. The other 30 reagents failed QC due to auto-agglutination (n=2), no reactivity with target serotypes (n=8) or cross-reactivity with non-target serotypes (n=20). Dilution of antisera resulted in a further 27 reagents passing QC. The remaining three reagents passed QC when prepared without centrifugation and wash steps. Protein estimates indicated that latex reagents that failed QC when prepared using the PCP method passed when made with antiserum containing ≤ 500 μg/ml of protein. Sixty-one nasopharyngeal isolates were serotyped with our in-house latex agglutination reagents, with the results showing complete concordance with the Quellung reaction. Conclusions The method described here to produce latex agglutination reagents allows simple and efficient serotyping of pneumococci and may be applicable to latex agglutination reagents for typing or identification of other microorganisms. We recommend diluting antisera or removing centrifugation and wash steps for any latex reagents that fail QC. Our latex reagents are cost-effective, technically undemanding to prepare and remain stable for long periods of time, making them ideal for

Serotype determination of Salmonella by xTAG assay.

PubMed

Zheng, Zhibei; Zheng, Wei; Wang, Haoqiu; Pan, Jincao; Pu, Xiaoying

2017-10-01

Currently, no protocols or commercial kits are available to determine the serotypes of Salmonella by using Luminex MAGPIX®. In this study, an xTAG assay for serotype determination of Salmonella suitable for Luminex MAGPIX® is described and 228 Salmonella isolates were serotype determined by this xTAG assay. The xTAG assay consists of two steps: 1) Multiplex PCR to amplify simultaneously O, H and Vi antigen genes of Salmonella, and 2) Magplex-TAG™ microsphere hybridization to identify accurately the specific PCR products of different antigens. Compared with the serotyping results of traditional serum agglutination test, the sensitivity and specificity of the xTAG assay were 95.1% and 100%, respectively. The agreement rate of these two assays was 95.2%. Compared with Luminex xMAP® Salmonella Serotyping Assay (SSA) kit, the advantages of this xTAG assay are: First, the magnetic beads make it applicable to both the Luminex®100/200™ and MAGPIX® systems. Second, only primers rather than both primers and probes are needed in the xTAG assay, and the process of coupling antigen-specific oligonucleotide probes to beads is circumvented, which make the xTAG assay convenient to be utilized by other laboratories. The xTAG assay may serve as a rapid alternative or complementary method for traditional Salmonella serotyping tests, especially for laboratories that utilize the MAGPIX® systems. Copyright © 2017 Elsevier B.V. All rights reserved.

A comparison of machine learning and Bayesian modelling for molecular serotyping.

PubMed

Newton, Richard; Wernisch, Lorenz

2017-08-11

Streptococcus pneumoniae is a human pathogen that is a major cause of infant mortality. Identifying the pneumococcal serotype is an important step in monitoring the impact of vaccines used to protect against disease. Genomic microarrays provide an effective method for molecular serotyping. Previously we developed an empirical Bayesian model for the classification of serotypes from a molecular serotyping array. With only few samples available, a model driven approach was the only option. In the meanwhile, several thousand samples have been made available to us, providing an opportunity to investigate serotype classification by machine learning methods, which could complement the Bayesian model. We compare the performance of the original Bayesian model with two machine learning algorithms: Gradient Boosting Machines and Random Forests. We present our results as an example of a generic strategy whereby a preliminary probabilistic model is complemented or replaced by a machine learning classifier once enough data are available. Despite the availability of thousands of serotyping arrays, a problem encountered when applying machine learning methods is the lack of training data containing mixtures of serotypes; due to the large number of possible combinations. Most of the available training data comprises samples with only a single serotype. To overcome the lack of training data we implemented an iterative analysis, creating artificial training data of serotype mixtures by combining raw data from single serotype arrays. With the enhanced training set the machine learning algorithms out perform the original Bayesian model. However, for serotypes currently lacking sufficient training data the best performing implementation was a combination of the results of the Bayesian Model and the Gradient Boosting Machine. As well as being an effective method for classifying biological data, machine learning can also be used as an efficient method for revealing subtle biological

Behavior of Avirulent Yersinia pestis in Liquid Whole Egg as Affected by Antimicrobials and Thermal Pasteurization

USDA-ARS?s Scientific Manuscript database

Yersinia spp. is a psychrotrophic bacterium that can grow at temperatures as low as minus two degrees Celsius, and is known to contaminate shell eggs in the United States and shell eggs and liquid egg in South America. A study was performed to determine the thermal sensitivity of avirulent Yersinia...

Serotype classification of Streptococcus mutans and its detection outside the oral cavity.

PubMed

Nakano, Kazuhiko; Ooshima, Takashi

2009-09-01

Streptococcus mutans, generally known as a major pathogen of dental caries, is also a possible causative agent of bacteremia and infective endocarditis. S. mutans is classified into serotypes c, e, f and k based on the chemical composition of serotype-specific polysaccharides, with approximately 70-80% of strains found in the oral cavity classified as serotype c, followed by e (approximately 20%), and f and k (less than 5% each). Serotype k was recently designated as a novel serotype and shown to possess unique features, the most prominent being a defect of the glucose side chain in serotype-specific rhamnose-glucose polymers, which is related to a higher incidence of detection in cardiovascular specimens, owing to phagocytosis resistance. Molecular analyses of cardiovascular specimens showed a high detection frequency for S. mutans DNA, among which the detection rate for serotype k was quite high. These findings suggest that serotype k S. mutans possibly has a high level of virulence for systemic diseases.

Blood invasiveness of Salmonella enterica as a function of age and serotype.

PubMed Central

Weinberger, M.; Andorn, N.; Agmon, V.; Cohen, D.; Shohat, T.; Pitlik, S. D.

2004-01-01

We explored the dual influence of the patient's age and the infecting serotype on the blood invasiveness patterns of non-Typhi Salmonella enterica (NTS). Blood invasiveness ratio (BIR) was calculated as the ratio between the number of blood and blood + stool isolates. Analysis of 14,951 NTS isolates showed that the BIR increased drastically above the age of 60 years, reaching levels 3.5-7 times higher compared to age group < 2 years. Different patterns of age-related invasiveness were observed for the five most common NTS serotypes (Enteritidis, Typhimurium, Virchow, Hadar, Infantis). Among children < 2 years, the BIR was highest for serotype Virchow and lowest for serotype Hadar, while in persons > or = 60 years it was highest for serotypes Enteritidis and lowest for serotype Infantis. The tendency of NTS serotypes to invade the bloodstream was significantly influenced by the patient's age, however the impact of age differed for various NTS serotypes. PMID:15635958

Structural and Genetic Analyses of O Polysaccharide from Actinobacillus actinomycetemcomitans Serotype f

PubMed Central

Kaplan, Jeffrey B.; Perry, Malcolm B.; MacLean, Leann L.; Furgang, David; Wilson, Mark E.; Fine, Daniel H.

2001-01-01

The oral bacterium Actinobacillus actinomycetemcomitans is implicated as a causative agent of localized juvenile periodontitis (LJP). A. actinomycetemcomitans is classified into five serotypes (a to e) corresponding to five structurally and antigenically distinct O polysaccharide (O-PS) components of their respective lipopolysaccharide molecules. Serotype b has been reported to be the dominant serotype isolated from LJP patients. We determined the lipopolysaccharide O-PS structure from A. actinomycetemcomitans CU1000, a strain isolated from a 13-year-old African-American female with LJP which had previously been classified as serotype b. The O-PS of strain CU1000 consisted of a trisaccharide repeating unit composed of l-rhamnose and 2-acetamido-2-deoxy-d-galactose (molar ratio, 2:1) with the structure →2)-α-l-Rhap-(1–3)-2-O-(β-d-GalpNAc)-α-l-Rhap-(1→. O-PS from strain CU1000 was structurally and antigenically distinct from the O-PS molecules of the five known A. actinomycetemcomitans serotypes. Strain CU1000 was mutagenized with transposon IS903φkan, and three mutants that were deficient in O-PS synthesis were isolated. All three transposon insertions mapped to a single 1-kb region on the chromosome. The DNA sequence of a 13.1-kb region surrounding these transposon insertions contained a cluster of 14 open reading frames that was homologous to gene clusters responsible for the synthesis of A. actinomycetemcomitans serotype b, c, and e O-PS antigens. The CU1000 gene cluster contained two genes that were not present in serotype-specific O-PS antigen clusters of the other five known A. actinomycetemcomitans serotypes. These data indicate that strain CU1000 should be assigned to a new A. actinomycetemcomitans serotype, designated serotype f. A PCR assay using serotype-specific PCR primers showed that 3 out of 20 LJP patients surveyed (15%) harbored A. actinomycetemcomitans strains carrying the serotype f gene cluster. The finding of an A

Spatial pattern of foot-and-mouth disease virus serotypes in North Central Nigeria

PubMed Central

Wungak, Yiltawe Simwal; Ishola, Olayinka O.; Olugasa, Babasola O.; Lazarus, David D.; Ehizibolo, David O.; Ularamu, Hussaini G.

2017-01-01

Aim: This study aimed to determine the foot-and-mouth disease virus (FMDV) serotypes circulating, the prevalence of FMDV serotypes, and the spatial distribution of FMDV among sedentary and pastoral cattle herds in the North-Central Nigeria. Materials and Methods: A cross-sectional study was undertaken, during which a total of 155 sera that tested positive for foot-and-mouth disease (FMD) 3ABC non-structural protein antibodies were selected and screened for FMD structural protein serotypes, A, O, SAT 1, and SAT 2 using a solid-phase competitive enzyme-linked immunosorbent assay (ELISA). Epithelial tissue specimens were collected during outbreak investigations which were tested for FMD using an antigen capture ELISA for serotype A, O, SAT 1, and SAT 2. Results: An overall serotype-specific prevalence of 79.35 (95% confidence interval [CI]: 72.4-85.18) was recorded for serotype O, 65.2% (95% CI: 57.41-72.3) for serotype A, 52.9% (95% CI: 45.03-60.67) for SAT 2, and 33.55% (95% CI: 26.45-41.26) for SAT 1. Evidence of exposure to multiple FMDV serotypes showed that 12.26% of the sera samples had antibodies against four serotypes circulating, 30.97% had antibodies against three serotypes circulating, 22.58% had antibodies against two serotypes, and 17% showed exposure to only one serotype. Clinical specimens (epithelial tissue) collected during outbreak investigations showed that serotype O has the highest proportion of 50% with serotype A - 25%; SAT 2 - 20.8%; and SAT 1 - 4.1%. Conclusion: The study detected diffuse and co-circulation of serotypes A, O, SAT 1, and SAT 2 within the study area, and hence the need for the appropriately matched multivalent vaccine is strongly advocated for FMD control in Nigeria. PMID:28507418

Novel colicin Fy of Yersinia frederiksenii inhibits pathogenic Yersinia strains via YiuR-mediated reception, TonB import, and cell membrane pore formation.

PubMed

Bosák, Juraj; Laiblová, Petra; Smarda, Jan; Dedicová, Daniela; Smajs, David

2012-04-01

A novel colicin type, designated colicin Fy, was found to be encoded and produced by the strain Yersinia frederiksenii Y27601. Colicin Fy was active against both pathogenic and nonpathogenic strains of the genus Yersinia. Plasmid YF27601 (5,574 bp) of Y. frederiksenii Y27601 was completely sequenced. The colicin Fy activity gene (cfyA) and the colicin Fy immunity gene (cfyI) were identified. The deduced amino acid sequence of colicin Fy was very similar in its C-terminal pore-forming domain to colicin Ib (69% identity in the last 178 amino acid residues), indicating pore forming as its lethal mode of action. Transposon mutagenesis of the colicin Fy-susceptible strain Yersinia kristensenii Y276 revealed the yiuR gene (ykris001_4440), which encodes the YiuR outer membrane protein with unknown function, as the colicin Fy receptor molecule. Introduction of the yiuR gene into the colicin Fy-resistant strain Y. kristensenii Y104 restored its susceptibility to colicin Fy. In contrast, the colicin Fy-resistant strain Escherichia coli TOP10F' acquired susceptibility to colicin Fy only when both the yiuR and tonB genes from Y. kristensenii Y276 were introduced. Similarities between colicins Fy and Ib, similarities between the Cir and YiuR receptors, and the detected partial cross-immunity of colicin Fy and colicin Ib producers suggest a common evolutionary origin of the colicin Fy-YiuR and colicin Ib-Cir systems.

Novel Colicin FY of Yersinia frederiksenii Inhibits Pathogenic Yersinia Strains via YiuR-Mediated Reception, TonB Import, and Cell Membrane Pore Formation

PubMed Central

Bosák, Juraj; Laiblová, Petra; Šmarda, Jan; Dědičová, Daniela

2012-01-01

A novel colicin type, designated colicin FY, was found to be encoded and produced by the strain Yersinia frederiksenii Y27601. Colicin FY was active against both pathogenic and nonpathogenic strains of the genus Yersinia. Plasmid YF27601 (5,574 bp) of Y. frederiksenii Y27601 was completely sequenced. The colicin FY activity gene (cfyA) and the colicin FY immunity gene (cfyI) were identified. The deduced amino acid sequence of colicin FY was very similar in its C-terminal pore-forming domain to colicin Ib (69% identity in the last 178 amino acid residues), indicating pore forming as its lethal mode of action. Transposon mutagenesis of the colicin FY-susceptible strain Yersinia kristensenii Y276 revealed the yiuR gene (ykris001_4440), which encodes the YiuR outer membrane protein with unknown function, as the colicin FY receptor molecule. Introduction of the yiuR gene into the colicin FY-resistant strain Y. kristensenii Y104 restored its susceptibility to colicin FY. In contrast, the colicin FY-resistant strain Escherichia coli TOP10F′ acquired susceptibility to colicin FY only when both the yiuR and tonB genes from Y. kristensenii Y276 were introduced. Similarities between colicins FY and Ib, similarities between the Cir and YiuR receptors, and the detected partial cross-immunity of colicin FY and colicin Ib producers suggest a common evolutionary origin of the colicin FY-YiuR and colicin Ib-Cir systems. PMID:22343298

Effect of serotonin on the expression of antigens and DNA levels in Yersinia pestis cells with different plasmid content

NASA Astrophysics Data System (ADS)

Klueva, Svetlana N.; Korsukov, Vladimir N.; Schukovskaya, Tatyana N.; Kravtsov, Alexander L.

2004-08-01

Using flow cytometry (FCM) the influence of exogenous serotonin on culture growth, DNA content and fluorescence intensity of cells binding FITC-labelled plague polyclonal immunoglobulins was studied in Yersinia pestis EV (pFra+, pCad+, pPst+), Yersinia pestis KM218 (pFra-, pCad-, pPst-), Yersinia pestis KM 216 (pFra-, pCad-, pPst+). The results have been obtained by FCM showed serotonin accelerated Yersinia pestis EV (pFra+, pCad+, pPst+), Yersinia pestis KM218 (pFra-, pCad-, pPst-) culture growth during cultivation in Hottinger broth pH 7.2 at 28°C at concentration of 10-5 M. The presence of 10-5 M serotonin in nutrient broth could modulate DNA content in 37°C growing population of plague microbe independently of their plasmid content. Serotonin have been an impact on the distribution pattern of the cells according to their phenotypical characteristics, which was reflected in the levels of population heterogeneity in the intensity of specific immunofluorescence determined by FMC.

Salmonella, Shigella, and Yersinia

PubMed Central

Dekker, John; Frank, Karen

2015-01-01

Synopsis Salmonella, Shigella, and Yersinia cause a well-characterized spectrum of disease in humans, ranging from asymptomatic carriage to hemorrhagic colitis and fatal typhoidal fever. These pathogens are responsible for millions of cases of food-borne illness in the U.S. each year, with substantial costs measured in hospitalizations and lost productivity. In the developing world, illness caused by these pathogens is not only more prevalent, but is also associated with a greater case-fatality rate. Classical methods for identification rely on selective media and serology, but newer methods based on mass spectrometry and PCR show great promise for routine clinical testing. PMID:26004640

Transmission of foodborne zoonotic pathogens to riparian areas by grazing sheep

PubMed Central

Sutherland, Sara J.; Gray, Jeffrey T.; Menzies, Paula I.; Hook, Sarah E.; Millman, Suzanne T.

2009-01-01

The objective of this study was to determine if sheep grazing near riparian areas on pasture in Ontario are an important risk factor for the contamination of water with specific foodborne pathogens. Ten Ontario sheep farms were visited weekly for 12 wk during the summer of 2005. Samples of feces, soil, and water were collected and analyzed for the presence of Escherichia coli O157:H7, Salmonella spp., Campylobacter jejuni and C. coli, and Yersinia enterocolitica, by bacteriological identification and polymerase chain reaction (PCR). The data was analyzed as repeated measures over time using mixed models. No samples were positive for Salmonella, and no samples were confirmed positive for E. coli O157:H7 after PCR. Levels of Campylobacter were highest in the soil, but did not differ between soil where sheep grazed or camped and roadside soil that had never been grazed (P = 0.85). Levels of Yersinia were highest in water samples and were higher in soil where sheep had access (P = 0.01). The prevalence of positive Campylobacter and Yersinia samples were not associated with locations where sheep spent more time (Campylobacter P = 0.46, Yersinia P = 0.99). There was no effect of stocking density on the prevalence of Campylobacter (P = 0.30), but as the stocking density increased the levels of Yersinia increased (P = 0.04). It was concluded that although sheep transmit Yersinia to their environment, pastured sheep flocks are not major risk factors for the transmission of zoonotic pathogens into water. PMID:19436581

Bordetella pertussis isolates in Finland: Serotype and fimbrial expression

PubMed Central

Heikkinen, Eriikka; Xing, Dorothy K; Ölander, Rose-Marie; Hytönen, Jukka; Viljanen, Matti K; Mertsola, Jussi; He, Qiushui

2008-01-01

Background Bordetella pertussis causes whooping cough or pertussis in humans. It produces several virulence factors, of which the fimbriae are considered adhesins and elicit immune responses in the host. B. pertussis has three distinct serotypes Fim2, Fim3 or Fim2,3. Generally, B. pertussis Fim2 strains predominate in unvaccinated populations, whereas Fim3 strains are often isolated in vaccinated populations. In Finland, pertussis vaccination was introduced in 1952. The whole-cell vaccine contained two strains, 18530 (Fim3) since 1962 and strain 1772 (Fim2,3) added in 1976. After that the vaccine has remained the same until 2005 when the whole-cell vaccine was replaced by the acellular vaccine containing pertussis toxin and filamentous hemagglutinin. Our aims were to study serotypes of Finnish B. pertussis isolates from 1974 to 2006 in a population with > 90% vaccination coverage and fimbrial expression of the isolates during infection. Serotyping was done by agglutination and serotype-specific antibody responses were determined by blocking ELISA. Results Altogether, 1,109 isolates were serotyped. Before 1976, serotype distributions of Fim2, Fim3 and Fim2,3 were 67%, 19% and 10%, respectively. From 1976 to 1998, 94% of the isolates were Fim2 serotype. Since 1999, the frequency of Fim3 strains started to increase and reached 83% during a nationwide epidemic in 2003. A significant increase in level of serum IgG antibodies against purified fimbriae was observed between paired sera of 37 patients. The patients infected by Fim3 strains had antibodies which blocked the binding of monoclonal antibodies to Fim3 but not to Fim2. Moreover, about one third of the Fim2 strain infected patients developed antibodies capable of blocking of binding of both anti-Fim2 and Fim3 monoclonal antibodies. Conclusion Despite extensive vaccinations in Finland, B. pertussis Fim2 strains were the most common serotype. Emergence of Fim3 strains started in 1999 and coincided with nationwide

Characterization of avian paramyxovirus serotype 14, a novel serotype, isolated from a duck fecal sample in Japan.

PubMed

Thampaisarn, Rapeewan; Bui, Vuong N; Trinh, Dai Q; Nagai, Makoto; Mizutani, Tetsuya; Omatsu, Tsutomu; Katayama, Yukie; Gronsang, Dulyatad; Le, Duong H T; Ogawa, Haruko; Imai, Kunitoshi

2017-01-15

A hemagglutinating virus isolate designated 11OG0352, was obtained from a duck fecal sample. Genetic and virological analyses indicated that it might represent a novel serotype of avian paramyxovirus (APMV). Electron micrographs showed that the morphology of the virus particle was similar to that of APMV. The complete genome of this virus comprised 15,444 nucleotides complying with the paramyxovirus "rule of six" and contains six open reading frames (3'-N-P-M-F-HN-L-5'). The phylogenetic analysis of the whole genome revealed that the virus was a member of the genus Avulavirus, but that it was distinct from APMV-1 to APMV-13. Although the F-protein cleavage site was TREGK↓L, which resembles a lentogenic strain of APMV-1, the K residue at position -1 of the cleavage site was first discovered in APMV members. The phosphoprotein gene of isolate 11OG0352 contains a putative RNA editing site, 3'-AUUUUCCC-5' (negative sense) which sequence differs from that of other APMVs. The intracerebral pathogenicity index test did not detect virulence in infected chicks. In hemagglutination inhibition (HI) tests, an antiserum against this virus did not detectably react with other APMVs (serotypes 1-4, 6-9) except for low reciprocal cross-reactivity with APMV-6. We designated this isolate, as APMV-14/duck/Japan/11OG0352/2011 and propose that it is a novel APMV serotype. The HI test may not be widely applicable for the classification of a new serotype because of the limited availability of reference antisera against all serotypes and cross-reactivity data. The nucleotide sequence identities of the whole genome of 11OG0352 and other APMVs ranged from 46.3% to 56.1%. Such comparison may provide a useful tool for classifying new APMV isolates. However, the nucleotide sequence identity between APMV-12 and APMV-13 was higher (64%), which was nearly identical to the lowest nucleotide identity (67%) reported in subgroups within the serotype. Therefore, consensus criteria for using whole

Evaluation of the Role of the opgGH Operon in Yersinia pseudotuberculosis and Its Deletion during the Emergence of Yersinia pestis

PubMed Central

Quintard, Kévin; Dewitte, Amélie; Reboul, Angéline; Madec, Edwige; Bontemps-Gallo, Sébastien; Dondeyne, Jacqueline; Marceau, Michaël; Simonet, Michel

2015-01-01

The opgGH operon encodes glucosyltransferases that synthesize osmoregulated periplasmic glucans (OPGs) from UDP-glucose, using acyl carrier protein (ACP) as a cofactor. OPGs are required for motility, biofilm formation, and virulence in various bacteria. OpgH also sequesters FtsZ in order to regulate cell size according to nutrient availability. Yersinia pestis (the agent of flea-borne plague) lost the opgGH operon during its emergence from the enteropathogen Yersinia pseudotuberculosis. When expressed in OPG-negative strains of Escherichia coli and Dickeya dadantii, opgGH from Y. pseudotuberculosis restored OPGs synthesis, motility, and virulence. However, Y. pseudotuberculosis did not produce OPGs (i) under various growth conditions or (ii) when overexpressing its opgGH operon, its galUF operon (governing UDP-glucose), or the opgGH operon or Acp from E. coli. A ΔopgGH Y. pseudotuberculosis strain showed normal motility, biofilm formation, resistance to polymyxin and macrophages, and virulence but was smaller. Consistently, Y. pestis was smaller than Y. pseudotuberculosis when cultured at ≥37°C, except when the plague bacillus expressed opgGH. Y. pestis expressing opgGH grew normally in serum and within macrophages and was fully virulent in mice, suggesting that small cell size was not advantageous in the mammalian host. Lastly, Y. pestis expressing opgGH was able to infect Xenopsylla cheopis fleas normally. Our results suggest an evolutionary scenario whereby an ancestral Yersinia strain lost a factor required for OPG biosynthesis but kept opgGH (to regulate cell size). The opgGH operon was presumably then lost because OpgH-dependent cell size control became unnecessary. PMID:26150539

[Identification of rotavirus associated to serotype G2 in Yucatan, Mexico].

PubMed

Gonzales-Loza, M del R; Polanco-Marín, G G; Puerto-Solis, M

2000-01-01

In the present study, rotavirus G2 serotype was identified from fecal samples of children with gastroenteritis from the city of Merida, Yucatan, Mexico. Virological diagnosis of disease was performed using polycrylamide gel electrophoresis and immunoenzymatic assay. Out of 149 analyzed samples 25 (16.7%) gave positive reaction to rotavirus groups A, of these 23 (92%) were identified as serotype g2, subgroup i and electrophoretic short pattern, whereas 2 (8%) were identified as subgroups II and electrophoretic long pattern, however, the G serotype was not possible to determine. Rotavirus G serotype has not been detected in more than 90% of samples since 1985. This indicates that the number of people susceptible to G2 serotype within the population has increased over recent years, which perhaps indicates that an important outbreak of acute infectious diarrhea caused by the rotavirus G2 serotype may be forthcoming.

Serotype Distribution of Salmonella Isolates from Turkey Ground Meat and Meat Parts

PubMed Central

Erol, Irfan; Goncuoglu, Muammer; Ayaz, Naim Deniz; Ellerbroek, Lüppo; Bilir Ormanci, Fatma Seda; Iseri Kangal, Ozlem

2013-01-01

The aim of the study was to find out the serotype distribution of 169 Salmonella colonies recovered from 112 Salmonella positive ground turkey (115 colonies) and 52 turkey meat parts (54 colonies). Out of 15 Salmonella serotypes: S. Corvallis, S. Kentucky, S. Bredeney, S. Virchow, S. Saintpaul and S. Agona were identified as the predominant serovars at the rates of 27%, 13%, 12%, 12%, 11%, and 10%, respectively. Other serotypes were below 6% of the total isolates. All S. Kentucky and S. Virchow and most of the S. Corvallis (39/46) and S. Heidelberg (9/9) serotypes were recovered from ground turkey. The results indicate that turkey ground meat and meat parts were contaminated with quite distinct Salmonella serotypes. This is the first study reporting Salmonella serotype distribution in turkey meat and S. Corvallis as predominant serotype in poultry meat in Turkey. PMID:23936785

Salmonella serotype distribution in the Dutch broiler supply chain.

PubMed

van Asselt, E D; Thissen, J T N M; van der Fels-Klerx, H J

2009-12-01

Salmonella serotype distribution can give insight in contamination routes and persistence along a production chain. Therefore, it is important to determine not only Salmonella prevalence but also to specify the serotypes involved at the different stages of the supply chain. For this purpose, data from a national monitoring program in the Netherlands were used to estimate the serotype distribution and to determine whether this distribution differs for the available sampling points in the broiler supply chain. Data covered the period from 2002 to 2005, all slaughterhouses (n = 22), and the following 6 sampling points: departure from hatchery, arrival at the farm, departure from the farm, arrival at the slaughterhouse, departure from the slaughterhouse, and end of processing. Furthermore, retail data for 2005 were used for comparison with slaughterhouse data. The following serotypes were followed throughout the chain: Salmonella Enteritidis, Salmonella Typhimurium, Salmonella Paratyphi B var. Java (Salmonella Java), Salmonella Infantis, Salmonella Virchow, and Salmonella Mbandaka. Results showed that serotype distribution varied significantly throughout the supply chain (P < 0.05). Main differences were found at the farm and at the slaughterhouse (within one stage), and least differences were found between departure from one stage and arrival at the next stage. The most prominent result was the increase of Salmonella Java at farm level. This serotype remained the most prominent pathogen throughout the broiler supply chain up to the retail phase.

Genetic and structural elucidation of capsular polysaccharides from Streptococcus pneumoniae serotype 23A and 23B, and comparison to serotype 23F.

PubMed

Ravenscroft, Neil; Omar, Aneesa; Hlozek, Jason; Edmonds-Smith, Cesarina; Follador, Rainer; Serventi, Fabio; Lipowsky, Gerd; Kuttel, Michelle M; Cescutti, Paola; Faridmoayer, Amirreza

2017-10-10

Streptococcus pneumoniae is a globally important encapsulated human pathogen with approximately 100 different serotypes recognized. Serogroup 23 consists of serotype 23F, present in licensed vaccines, and emerging serotypes 23A and 23B. Here, we report the previously unknown structures of the pneumococcal capsular polysaccharides serotype 23A and 23B determined using genetic analysis, NMR spectroscopy, composition and linkage analysis and Smith degradation (of polysaccharide 23A). The structure of the serotype 23A capsular polysaccharide is: →4)-β-D-Glcp-(1→3)-[[α-L-Rhap-(1→2)]-[Gro-(2→P→3)]-β-D-Galp-(1→4)]-β-L-Rhap-(1→. This structure differs from polysaccharide 23F as it features a disaccharide backbone and the di-substituted β-Gal is linked to β-Rha as a side chain. This is due to the different polymerization position catalysed by the unusually divergent repeat unit polymerase Wzy in the 23A cps biosynthesis locus. Steric crowding in 23A, confirmed by molecular models, causes the NMR signal for H-1 of the di-substituted 2,3-β-Gal to resonate in the α-anomeric region. The structure of the serotype 23B capsular polysaccharide is the same as 23F, but without the terminal α-Rha: →4)-β-D-Glcp-(1→4)-[Gro-(2→P→3)]-β-D-Galp-(1→4)-β-L-Rhap-(1→. The immunodominant terminal α-Rha of 23F is more sterically crowded in 23A and absent in 23B. This may explain the reported typing cross reactions for serotype 23F: slight with 23A and none with 23B. Copyright © 2017 Elsevier Ltd. All rights reserved.

Granulocyte phagocytosis and killing virulent and avirulent serotypes of Streptococcus pneumoniae.

PubMed

Braconier, J H; Odeberg, H

1982-08-01

Five commonly isolated Streptococcus pneumoniae serotypes (3, 6, 14, 19, and 23) and five rarely found serotypes (31, 35, 36, 42, and 43) were compared to elucidate whether increased resistance against granulocyte phagocytosis and killing could explain the restricted number of pneumococcal serotypes found in infections. There was a great variation in sensitivity among the serotypes to granulocyte killing. No consistent pattern was found when pathogenicity and resistance to granulocytes were compared. The results do not indicate that the increased tendency of pathogenic pneumococcal serotypes to cause infections is due to increased resistance to granulocytes. Monocyte killing of some pneumococal serotypes (6, 19, 23, 35, and 43) was also studied and found very similar to granulocyte killing. Defective granulocyte kiling of encapsulated pneumococci was due to impaired phagocytosis. Moreover, no correlation was found between the sensitivity of the serotypes to isolated intragranulocytic microbial systems (i.e., MPO, hydrogen peroxide, or CCP) and the sensitivity to killing by intact granulocytes or pathogenicity. The significance of both the classical and alternative complement pathways for pneumococcal opsonization was indicated by reduced, the residual phagocytosis in C2-deficient and MgEGTA-chelated serum.

Microcapsules on Streptococcus mutans serotypes by electron microscopy.

PubMed

Grenier, E M; Gray, R H; Loesche, W J; Eveland, W C

1977-02-01

Extracellular microcapsules have been demonstrated on cells of most serotypes of Streptococcus mutans by electron microscopy, using bacterial strains of the various serotypes and peroxidase labeled or unlabeled immune serum. A correlation was noted between the amount of capsular substance on the strains of S mutans examined and degree of antigenicity as expressed by the indirect fluorescent antibody (FA) title. A serotype d strain was shown to lose both antigenicity as determined by the FA reaction and capsular material as seen by electron microscopy with repeated in vitro passage. When 10% unheated rabbit serum was added to the medium, antigenicity and capsular material were restored.

Rescue and serotypic characterization of noncultivable human rotavirus by gene reassortment.

PubMed Central

Greenberg, H B; Wyatt, R G; Kapikian, A Z; Kalica, A R; Flores, J; Jones, R

1982-01-01

Thirty-three of 50 noncultivable human rotavirus strains from a variety of locations were successfully rescued by gene reassortment. The serotype of each of the 33 strains was investigated by a qualitative cytopathic effect neutralization assay. Nineteen strains resembled the previously characterized human rotavirus serotype Wa, whereas three strains were serologically related to the DS-1 strain. Eleven strains appeared to be serotypically distinct from the Wa and DS-1 strains and thus apparently represent one or more new human rotavirus serotypes. Images PMID:6286486

First environmental isolation of Cryptococcus gattii serotype B, from Cúcuta, Colombia.

PubMed

Firacative, Carolina; Torres, Germán; Rodríguez, María Claudia; Escandón, Patricia

2011-03-01

In Cúcuta, Cryptococcus gattii serotype B is commonly recovered from immunocompetent patients with cryptococcosis, but it has not been recovered from the environment in spite of its high incidence which is 77% out of reported cases. The aim of this work was to carry out an extensive environmental sampling in Cúcuta, in an attempt to isolate C. gattii serotype B and to expand our knowledge about the ecology and epidemiology of this important yeast. Samples associated with 3,634 trees from 40 zones of Cúcuta were collected and processed with 28 samples collected near the houses of four patients with cryptococcosis caused by C. gattii serotype B. The serotype of the recovered isolates was done using multiplex PCR, molecular patterns were determined by RFLP of the URA5 gene and mating type was determined using the primers MfαU, MfαL, MFa2U and MFa2L. In total, 4,389 samples were processed and one isolate of C. gattii serotype B (VGI/a), two isolates of C. gattii serotype C (VGIII/α) and three isolates of C. neoformans var. grubii, serotype A (VNI/α), were recovered. The density of the recovered isolates varied from 50 to 350 cfu/g of soil. This is the first report on the environmental isolation of C. gattii serotype B from Cúcuta. However, because of the low rate of recovery of isolates from soil only, the environmental niche of C. gattii has not been established and further environmental studies in Cúcuta are necessary, owing that this serotype is not only causing cryptococcosis but also has shown a higher virulence after the Vancouver outbreak.

Influenza A Virus Infection Predisposes Hosts to Secondary Infection with Different Streptococcus pneumoniae Serotypes with Similar Outcome but Serotype-Specific Manifestation.

PubMed

Sharma-Chawla, Niharika; Sender, Vicky; Kershaw, Olivia; Gruber, Achim D; Volckmar, Julia; Henriques-Normark, Birgitta; Stegemann-Koniszewski, Sabine; Bruder, Dunja

2016-12-01

Influenza A virus (IAV) and Streptococcus pneumoniae are major causes of respiratory tract infections, particularly during coinfection. The synergism between these two pathogens is characterized by a complex network of dysregulated immune responses, some of which last until recovery following IAV infection. Despite the high serotype diversity of S. pneumoniae and the serotype replacement observed since the introduction of conjugate vaccines, little is known about pneumococcal strain dependency in the enhanced susceptibility to severe secondary S. pneumoniae infection following IAV infection. Thus, we studied how preinfection with IAV alters host susceptibility to different S. pneumoniae strains with various degrees of invasiveness using a highly invasive serotype 4 strain, an invasive serotype 7F strain, and a carrier serotype 19F strain. A murine model of pneumococcal coinfection during the acute phase of IAV infection showed a significantly increased degree of pneumonia and mortality for all tested pneumococcal strains at otherwise sublethal doses. The incidence and kinetics of systemic dissemination, however, remained bacterial strain dependent. Furthermore, we observed strain-specific alterations in the pulmonary levels of alveolar macrophages, neutrophils, and inflammatory mediators ultimately affecting immunopathology. During the recovery phase following IAV infection, bacterial growth in the lungs and systemic dissemination were enhanced in a strain-dependent manner. Altogether, this study shows that acute IAV infection predisposes the host to lethal S. pneumoniae infection irrespective of the pneumococcal serotype, while the long-lasting synergism between IAV and S. pneumoniae is bacterial strain dependent. These results hold implications for developing tailored therapeutic treatment regimens for dual infections during future IAV outbreaks. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Yersinia pestis targets neutrophils via complement receptor 3

PubMed Central

Merritt, Peter M.; Nero, Thomas; Bohman, Lesley; Felek, Suleyman; Krukonis, Eric S.; Marketon, Melanie M.

2015-01-01

Yersinia species display a tropism for lymphoid tissues during infection, and the bacteria select innate immune cells for delivery of cytotoxic effectors by the type III secretion system. Yet the mechanism for target cell selection remains a mystery. Here we investigate the interaction of Yersinia pestis with murine splenocytes to identify factors that participate in the targeting process. We find that interactions with primary immune cells rely on multiple factors. First, the bacterial adhesin Ail is required for efficient targeting of neutrophils in vivo. However, Ail does not appear to directly mediate binding to a specific cell type. Instead, we find that host serum factors direct Y. pestis to specific innate immune cells, particularly neutrophils. Importantly, specificity towards neutrophils was increased in the absence of bacterial adhesins due to reduced targeting of other cell types, but this phenotype was only visible in the presence of mouse serum. Addition of antibodies against complement receptor 3 and CD14 blocked target cell selection, suggesting that a combination of host factors participate in steering bacteria toward neutrophils during plague infection. PMID:25359083

Serotype and mating type characterization of Cryptococcus neoformans by multiplex PCR.

PubMed

Carvalho, Vívian Gonçalves; Terceti, Mateus Souza; Dias, Amanda Latercia Tranches; Paula, Claudete Rodrigues; Lyon, Juliana Pereira; de Siqueira, Antônio Martins; Franco, Marília Caixeta

2007-01-01

Cryptococcus neoformans is an encapsulated yeast, etiological agent of cryptococcosis. The species is commonly associated with pigeon droppings and plant materials. The aim of the present work was to verify the presence of the yeast in pigeon droppings, and to identify the isolates obtained in serotypes and mating types (MAT). Ten samples of pigeon droppings were collected in the rural area of the city of Alfenas, Brazil. Samples were inoculated in agar Niger medium for fungal isolation and 22 isolates with characteristics of C. neoformans were obtained. The serotypes and MAT were determined by multiplex PCR using specific primers. Serotypes were also determined by using the Kit Crypto Check. Among the 22 samples evaluated, eight were identified as C. neoformans by classic identification tests. These samples were characterized as serotype A by the Kit Crypto check and as serotype A MAT alpha by the multiplex PCR. The present study reinforces the evidence that pigeon droppings are a reservoir for C. neoformans and confirms the prevalence of C. neoformans var. grubii (A alpha) among environmental isolates. It also demonstrates that multiplex PCR is an acceptable alternative for serotype analysis because it reduces the costs for each reaction and analyses serotype and MAT simultaneously.

Bacteriophages of Yersinia pestis.

PubMed

Zhao, Xiangna; Skurnik, Mikael

2016-01-01

Bacteriophage play many varied roles in microbial ecology and evolution. This chapter collates a vast body of knowledge and expertise on Yersinia pestis phages, including the history of their isolation and classical methods for their isolation and identification. The genomic diversity of Y. pestis phage and bacteriophage islands in the Y. pestis genome are also discussed because all phage research represents a branch of genetics. In addition, our knowledge of the receptors that are recognized by Y. pestis phage, advances in phage therapy for Y. pestis infections, the application of phage in the detection of Y. pestis, and clustered regularly interspaced short palindromic repeats (CRISPRs) sequences of Y. pestis from prophage DNA are all reviewed here.

In vitro probiotic characterization of Lactobacillus strains from fermented radish and their anti-adherence activity against enteric pathogens.

PubMed

Damodharan, Karthiyaini; Palaniyandi, Sasikumar Arunachalam; Yang, Seung Hwan; Suh, Joo-Won

2015-11-01

In this study, we evaluated the probiotic properties of Lactobacillus plantarum, Lactobacillus pentosus, and Lactobacillus fermentum strains isolated from fermented radish. All the strains survived the simulated oro-gastrointestinal transit condition and showed significantly higher adherence to Caco-2 cells compared with the probiotic strain Lactobacillus rhamnosus GG. The strains showed broad-spectrum antimicrobial activity, autoaggregation, and coaggregation capacity with pathogens. Furthermore, the Lactobacillus strains inhibited the adherence of Yersinia enterocolitica subsp. enterocolitica, Shigella boydii, and Salmonella choleraesuis to the Caco-2 cell line. The strains possessed bile salt hydrolase activity and their cholesterol-lowering activity in vitro was above 50% in the presence of bile. Strains of L. plantarum and L. pentosus possessed the plantaricin-encoding plnEF gene. In addition, the Lactobacillus strains maintained about 80% cell viability after freeze-drying in the presence of a combination of 5% skim milk and 5% maltodextrin as cryoprotectant, and 70% recovery of cell viability was observed in the absence of any cryoprotectant.

Characterization of chromosomal regions conserved in Yersinia pseudotuberculosis and lost by Yersinia pestis.

PubMed

Pouillot, Flavie; Fayolle, Corinne; Carniel, Elisabeth

2008-10-01

The transformation of the enteropathogenic bacterium Yersinia pseudotuberculosis into the plague bacillus, Yersinia pestis, has been accompanied by extensive genetic loss. This study focused on chromosomal regions conserved in Y. pseudotuberculosis and lost during its transformation into Y. pestis. An extensive PCR screening of 78 strains of the two species identified five regions (R1 to R5) and four open reading frames (ORFs; orf1 to orf4) that were conserved in Y. pseudotuberculosis and absent from Y. pestis. Their conservation in Y. pseudotuberculosis suggests a positive selective pressure and a role during the life cycle of this species. Attempts to delete two ORFs (orf3 and orf4) from the chromosome of strain IP32953 were unsuccessful, indicating that they are essential for its viability. The seven remaining loci were individually deleted from the IP32953 chromosome, and the ability of each mutant to grow in vitro and to kill mice upon intragastric infection was evaluated. Four loci (orf1, R2, R4, and R5) were not required for optimal growth or virulence of Y. pseudotuberculosis. In contrast, orf2, encoding a putative pseudouridylate synthase involved in RNA stability, was necessary for the optimal growth of IP32953 at 37 degrees C in a chemically defined medium (M63S). Deletion of R1, a region predicted to encode the methionine salvage pathway, altered the mutant pathogenicity, suggesting that the availability of free methionine is severely restricted in vivo. R3, a region composed mostly of genes of unknown functions, was necessary for both optimal growth of Y. pseudotuberculosis at 37 degrees C in M63S and for virulence. Therefore, despite their loss in Y. pestis, five of the nine Y. pseudotuberculosis-specific chromosomal loci studied play a role in the survival, growth, or virulence of this species.

Structural Insights into Ail-Mediated Adhesion in Yersinia pestis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yamashita, Satoshi; Lukacik, Petra; Barnard, Travis J.

2012-01-30

Ail is an outer membrane protein from Yersinia pestis that is highly expressed in a rodent model of bubonic plague, making it a good candidate for vaccine development. Ail is important for attaching to host cells and evading host immune responses, facilitating rapid progression of a plague infection. Binding to host cells is important for injection of cytotoxic Yersinia outer proteins. To learn more about how Ail mediates adhesion, we solved two high-resolution crystal structures of Ail, with no ligand bound and in complex with a heparin analog called sucrose octasulfate. We identified multiple adhesion targets, including laminin and heparin,more » and showed that a 40 kDa domain of laminin called LG4-5 specifically binds to Ail. We also evaluated the contribution of laminin to delivery of Yops to HEp-2 cells. This work constitutes a structural description of how a bacterial outer membrane protein uses a multivalent approach to bind host cells.« less

Differential impact of lipopolysaccharide defects caused by loss of RfaH in Yersinia pseudotuberculosis and Yersinia pestis.

PubMed

Hoffman, Jared M; Sullivan, Shea; Wu, Erin; Wilson, Eric; Erickson, David L

2017-09-07

RfaH enhances transcription of a select group of operons controlling bacterial surface features such as lipopolysaccharide (LPS). Previous studies have suggested that rfaH may be required for Yersinia pseudotuberculosis resistance to antimicrobial chemokines and survival during mouse infections. In order to further investigate the role of RfaH in LPS synthesis, resistance to host defense peptides, and virulence of Yersinia, we constructed ΔrfaH mutants of Y. pseudotuberculosis IP32953 and Y. pestis KIM6+. Loss of rfaH affected LPS synthesis in both species, resulting in a shorter core oligosaccharide. Susceptibility to polymyxin and the antimicrobial chemokine CCL28 was increased by loss of rfaH in Y. pseudotuberculosis but not in Y. pestis. Transcription of genes in the ddhD-wzz O-antigen gene cluster, but not core oligosaccharide genes, was reduced in ΔrfaH mutants. In addition, mutants with disruptions in specific ddhD-wzz O-antigen cluster genes produced LPS that was indistinguishable from the ΔrfaH mutant. This suggests that both Y. pseudotuberculosis and Y. pestis produce an oligosaccharide core with a single O-antigen unit attached in an RfaH-dependent fashion. Despite enhanced sensitivity to host defense peptides, the Y. pseudotuberculosis ΔrfaH strain was not attenuated in mice, suggesting that rfaH is not required for acute infection.

Serotype specific polymerase chain reaction identifies a higher prevalence of streptococcus mutans serotype k and e in a random group of children with dental caries from the Southern region of India.

PubMed

Rao, Arun Prasad; Austin, Ravi David

2014-07-01

The development of dental caries has been associated with the oral prevalence of Streptococcus mutans. Four serotypes of S. mutans have been reported, namely serotype c, e, f, and k that are classified based on the composition and linkages of cell wall polysaccharides, response to physiological reactions, sero-specificity and 16s rRNA homology. Although the oral prevalence of S. mutans serotype c in Indian subjects with or without caries is known, the prevalence of the other three serotypes, e, f, and k are not known. Hence in this study, we have investigated the occurrence of the e, f, and k serotypes in children with or without caries within the age group of 6-12 years. Genomic DNA isolated from whole saliva of caries active (CA) and caries free (CF) groups were first screened for the presence of S. mutans by strain specific polymerase chain reaction (PCR). Those samples that tested positive for the presence of S. mutans were further analyzed by serotype specific PCR to identify the prevalence of the serotypes. Strain specific PCR indicated a higher prevalence of S. mutans in CA group (80%) relative to CF group (43%). Further analysis of the S. mutans positive samples in both groups indicated a higher prevalence of serotype k and e, followed by serotype f in CA group. The present data clearly establishes a novel S. mutans serotype prevalence hierarchy in children from this region, compared with those that have been reported elsewhere. Besides, the data are also clinically significant as the occurrence of serotype k has been associated with infective endocarditis.

Analysis of loci required for determination of serotype antigenicity in Streptococcus mutans and its clinical utilization.

PubMed

Shibata, Yukie; Ozaki, Kazuhisa; Seki, Mitsuko; Kawato, Takayuki; Tanaka, Hideki; Nakano, Yoshio; Yamashita, Yoshihisa

2003-09-01

We recently identified the genes responsible for the serotype c-specific glucose side chain formation of rhamnose-glucose polysaccharide (RGP) in Streptococcus mutans. These genes were located downstream from the rgpA through rgpF locus that is involved in the synthesis of RGP. In the present study, the corresponding chromosomal regions were isolated from serotype e and f strains and characterized. The rgpA through rgpF homologs were well conserved among the three serotypes. By contrast, the regions downstream from the rgpF homolog differed considerably among the three serotypes. Replacement of these regions in the different serotype strains converted their serotypic phenotypes, suggesting that these regions participated in serotype-specific glucose side chain formation in each serotype strain. Based on the differences among the DNA sequences of these regions, a PCR method was developed to determine serotypes. S. mutans was isolated from 198 of 432 preschool children (3 to 4 years old). The serotypes of all but one S. mutans isolate were identified by serotyping PCR. Serotype c predominated (84.8%), serotype e was the next most common (13.3%), and serotype f occured rarely (1.9%) in Japanese preschool children. Caries experience in the group with a mixed infection by multiple serotypes of S. mutans was significantly higher than that in the group with a monoinfection by a single serotype.

Probability of identifying different salmonella serotypes in poultry samples

USDA-ARS?s Scientific Manuscript database

Recent work has called attention to the unequal competitive abilities of different Salmonella serotypes in standard broth culture and plating media. Such serotypes include Enteritidis and Typhimurium that are specifically targeted in some regulatory and certification programs because they cause a l...

Holo Structure and Steady State Kinetics of the Thiazolinyl Imine Reductases for Siderophore Biosynthesis

PubMed Central

Meneely, Kathleen M.; Ronnebaum, Trey A.; Riley, Andrew P.; Prisinzano, Thomas E.; Lamb, Audrey L.

2016-01-01

Thiazolinyl imine reductases catalyze the NADPH-dependent reduction of a thiazoline to a thiazolidine, a required step in the formation of the siderophores yersiniabactin (Yersinia spp.) and pyochelin (Pseudomonas aeruginosa). These stand-alone nonribosomal peptide tailoring domains are structural homologues of sugar oxidoreductases. Two closed structures of the thiazolinyl imine reductase from Yersinia enterocolitica (Irp3) are presented here: an NADP+-bound structure to 1.45 Å resolution and a holo structure to 1.28 Å resolution with NADP+ and a substrate analogue bound. Michaelis—Menten kinetics were measured using the same substrate analogue and the homologue from P. aeruginosa, PchG. The data presented here support the hypothesis that tyrosine 128 is the likely general acid residue for catalysis and also highlight the phosphopantetheine tunnel for tethering of the substrate to the nonribosomal peptide synthetase module during assembly line biosynthesis of the siderophore. PMID:27601130

Immunological relationships between glucosyltransferases from Streptococcus mutans serotypes.

PubMed

Kuramitsu, H; Ingersoll, L

1976-09-01

Partially purified glycosyltransferase enzymes for Streptococcus mutans GS-5 (serotype c) have been utilized to prepare antibodies directed against the soluble glucan-synthesizing activity, GTF-B, and the insoluble-soluble glucan synthetic activity, GTF-A. Anti-GTF-A inhibited insoluble glucan formation catalyzed by the extracellular enzymes from strains GS-5 and FA-1 (serotype b) to a much greater extent than that of strains HS-6 (serotype a) or OMZ-176 (serotype d). This antibody fraction also inhibited both the cell-associated glucosyltransferase activities as well as the sucrose-mediated adherence of cells to glass surfaces by strains GS-5 and FA-1 but not that of strains HS-6 and OMZ-176. Anti-GTF-B inhibited soluble glucan formation catalyzed by the extracellular enzymes of strains GS-5 but not that of strain HS-6, FA-1, or OMZ-176. However, this antibody fraction did not strongly inhibit either the cell-associated glycosyltransferase activity or cellular adherence of any of the four strains. These results with body antibody fractions were also correlated with the ability of the antibodies to agglutinate the cells and form precipitin bands after immunodiffusion with the extracellular enzymes. Antibody prepared against the homogeneous soluble glucan-synthesizing enzyme demonstrated similar effects to the anti-GTF-B fraction. These results are discussed in terms of the antigenic relationships existing between the glucosyltransferases from different serotypes of S. mutans.

Bayesian Estimation of the True Prevalence and of the Diagnostic Test Sensitivity and Specificity of Enteropathogenic Yersinia in Finnish Pig Serum Samples.

PubMed

Vilar, M J; Ranta, J; Virtanen, S; Korkeala, H

2015-01-01

Bayesian analysis was used to estimate the pig's and herd's true prevalence of enteropathogenic Yersinia in serum samples collected from Finnish pig farms. The sensitivity and specificity of the diagnostic test were also estimated for the commercially available ELISA which is used for antibody detection against enteropathogenic Yersinia. The Bayesian analysis was performed in two steps; the first step estimated the prior true prevalence of enteropathogenic Yersinia with data obtained from a systematic review of the literature. In the second step, data of the apparent prevalence (cross-sectional study data), prior true prevalence (first step), and estimated sensitivity and specificity of the diagnostic methods were used for building the Bayesian model. The true prevalence of Yersinia in slaughter-age pigs was 67.5% (95% PI 63.2-70.9). The true prevalence of Yersinia in sows was 74.0% (95% PI 57.3-82.4). The estimates of sensitivity and specificity values of the ELISA were 79.5% and 96.9%.

Are risk factors associated with invasive pneumococcal disease according to different serotypes?

PubMed

Ciruela, Pilar; Soldevila, Núria; Selva, Laura; Hernández, Sergi; Garcia-Garcia, Juan Jose; Moraga, Fernando; de Sevilla, Mariona F; Codina, Gemma; Planes, Ana Maria; Esteva, Cristina; Coll, Francis; Cardeñosa, Neus; Jordan, Iolanda; Batalla, Joan; Salleras, Luis; Muñoz-Almagro, Carmen; Domínguez, Angela

2013-03-01

The aim of this study was to investigate risk factors for the most common serotypes of invasive pneumococcal disease (IPD). A total of 293 IPD cases were analyzed in children aged 3-59 mo in a community with intermediate vaccination coverage with the 7-valent pneumococcal vaccine (PCV7). IPD cases were reviewed during 2007-2009 in two pediatric hospitals in Catalonia (Spain). A multivariate analysis using unconditional logistic regression was performed to estimate the adjusted odds ratio. PCV7 coverage was 45.4%. Pneumonia with empyema (64.5%) was the most frequent clinical manifestation. The most common serotypes were: serotype 1 (21.2%), 19A (16.0%), 3 (12.6%) and 7F/A (6.8%). 70.0% of serotypes found were included in the 13-valent conjugate vaccine (PCV13), 39.2% in the 10-valent conjugate vaccine and 8.1% in the PCV7. PCV7 was protective in IPD cases due to PCV7-serotypes (aOR: 0.15, 95% CI:0.04-0.55). Serotype 1 was positively associated with attending day care or school (aOR: 3.55, 95% CI: 1.21-10.38) and age 24-59 mo (aOR: 7.70, 95% CI:2.70-21.98). Serotype 19A was positively associated with respiratory infection in the previous month (aOR: 2.26, 95% CI: 1.03-4.94), non-penicillin susceptible IPD (aOR: 1.89, 95% CI:1.13-3.16) and negatively associated with age 24-59 mo (aOR: 0.19, 95% CI:0.09-0.41). Serotype 3 was positively associated with vaccination (aOR: 4.87, 95% CI:2.05-11.59). No factors were associated with serotype 7F/A. Vaccination with pneumococcal vaccines including more serotypes may reduce the risk of disease in our setting.

Cryptococcus neoformans var. grubii: Separate Varietal Status for Cryptococcus neoformans Serotype A Isolates

PubMed Central

Franzot, Sarah P.; Salkin, Ira F.; Casadevall, Arturo

1999-01-01

Cryptococcus neoformans var. neoformans presently includes isolates which have been determined by the immunologic reactivity of their capsular polysaccharides to be serotype A and those which have been determined to be serotype D. However, recent analyses of the URA5 sequences and DNA fingerprinting patterns suggest significant genetic differences between the two serotypes. Therefore, we propose to recognize these genotypic distinctions, as well as previously reported phenotypic differences, by restricting C. neoformans var. neoformans to isolates which are serotype D and describing a new variety, C. neoformans var. grubii, for serotype A isolates. PMID:9986871

Lung abscess caused by Streptococcus pneumoniae serotype 6B.

PubMed

Ito, Yuhei; Toyoshima, Hirokazu; Suzuki, Takehiro; Iwamoto, Keisuke; Sasano, Hajime; Itani, Hidetoshi; Kondo, Shigeto; Tanigawa, Motoaki

2018-01-01

Lung abscess has been considered to be a rare complication of pneumococcal infection, and most cases are reported to be Streptococcus pneumoniae serotype 3. A 67-year-old man presented with fever and was diagnosed to have lung abscess caused by S. pneumoniae serotype 6B. The minimal inhibitory concentration (MIC) of penicillin for the isolate was 1 μg/mL. He was treated with high-dose intravenous sulbactam/ampicillin as definitive therapy based on susceptibility testing for S. pneumoniae and recovered successfully without surgical intervention. S. pneumoniae serotype 6B can cause lung abscess.

Serotype specific polymerase chain reaction identifies a higher prevalence of streptococcus mutans serotype k and e in a random group of children with dental caries from the Southern region of India

PubMed Central

Rao, Arun Prasad; Austin, Ravi David

2014-01-01

Background: The development of dental caries has been associated with the oral prevalence of Streptococcus mutans. Four serotypes of S. mutans have been reported, namely serotype c, e, f, and k that are classified based on the composition and linkages of cell wall polysaccharides, response to physiological reactions, sero-specificity and 16s rRNA homology. Although the oral prevalence of S. mutans serotype c in Indian subjects with or without caries is known, the prevalence of the other three serotypes, e, f, and k are not known. Hence in this study, we have investigated the occurrence of the e, f, and k serotypes in children with or without caries within the age group of 6-12 years. Materials and Methods: Genomic DNA isolated from whole saliva of caries active (CA) and caries free (CF) groups were first screened for the presence of S. mutans by strain specific polymerase chain reaction (PCR). Those samples that tested positive for the presence of S. mutans were further analyzed by serotype specific PCR to identify the prevalence of the serotypes. Results: Strain specific PCR indicated a higher prevalence of S. mutans in CA group (80%) relative to CF group (43%). Further analysis of the S. mutans positive samples in both groups indicated a higher prevalence of serotype k and e, followed by serotype f in CA group. Conclusion: The present data clearly establishes a novel S. mutans serotype prevalence hierarchy in children from this region, compared with those that have been reported elsewhere. Besides, the data are also clinically significant as the occurrence of serotype k has been associated with infective endocarditis. PMID:25191062

Occurrence and analysis of irp2 virulence gene in isolates of Klebsiella pneumoniae and Enterobacter spp. from microbiota and hospital and community-acquired infections.

PubMed

Souza Lopes, Ana Catarina; Rodrigues, Juliana Falcão; Cabral, Adriane Borges; da Silva, Maíra Espíndola; Leal, Nilma Cintra; da Silveira, Vera Magalhães; de Morais Júnior, Marcos Antônio

2016-07-01

Eighty-five isolates of Klebsiella pneumoniae and Enterobacter spp., originating from hospital- and community-acquired infections and from oropharyngeal and faecal microbiota from patients in Recife-PE, Brazil, were analyzed regarding the presence of irp2 gene. This is a Yersinia typical gene involved in the synthesis of siderophore yersiniabactin. DNA sequencing confirmed the identity of irp2 gene in five K. pneumoniae, five Enterobacter aerogenes and one Enterobacter amnigenus isolates. To our knowledge in the current literature, this is the first report of the irp2 gene in E. amnigenus, a species considered an unusual human pathogen, and in K. pneumoniae and E. aerogenes isolates from the normal microbiota and from community infections, respectively. Additionally, the analyses of nucleotide and amino acid sequences suggest the irp2 genes derived from isolates used in this study are more closely related to that of Yersinia pestis P.CE882 than to that of Yersinia enterocolitica 8081. These data demonstrated that K. pneumoniae and Enterobacter spp. from normal microbiota and from community- and hospital-acquired infections possess virulence factors important for the establishment of extra-intestinal infections. Copyright © 2016 Elsevier Ltd. All rights reserved.

Genetic relationships and clonal population structure of serotype 2 strains of Neisseria meningitidis.

PubMed Central

Caugant, D A; Zollinger, W D; Mocca, L F; Frasch, C E; Whittam, T S; Frøholm, L O; Selander, R K

1987-01-01

Two hundred and thirty-four strains of Neisseria meningitidis, including 94 serotype 2a, 111 serotype 2b, and 19 serotype 2c isolates, together with 10 isolates that were serotyped as 2 with polyvalent antiserum but did not react with monoclonal antibodies, were characterized by the electrophoretic mobilities of 15 metabolic enzymes. Of these enzymes, 14 were polymorphic, and 56 distinctive combinations of alleles at the enzyme loci (electrophoretic types) were identified, among which the mean genetic diversity per locus was 0.413, or about 75% of that recorded for the species N. meningitidis as a whole. Mean genetic diversity among electrophoretic types of the same serotype (2a, 2b, or 2c) was, however, on average, less than half the total species diversity, and no multilocus genotypes were shared between isolates of the different serotypes, which belong to distinctive clonal lineages. Recent temporal changes in the frequencies of recovery of pathogenic strains of serotypes 2a and 2b in South Africa and North America resulted from clone replacement in these populations rather than evolutionary modification of the serotype protein of the initially dominant clones. PMID:3106223

The prevalence of dengue virus serotypes in asymptomatic blood donors reveals the emergence of serotype 4 in Saudi Arabia.

PubMed

Ashshi, Ahmed Mohamed

2017-06-09

Transmission of dengue virus (DENV) through blood transfusion has been documented and hence screening for DENV during blood donation has been recently recommended by the American Association of Blood Banks and Centres of Disease Control and Prevention. DENV is endemic in the Western province of the Kingdom of Saudi Arabia (KSA) and serotypes 1, 2 and 3, but not 4, have been detected. However, little is known regarding the rates of DENV during blood donation in the kingdom. The aim of this study was therefore to measure the prevalence of dengue virus and its serotypes in eligible Saudi blood donors in the endemic Western region of KSA. This was a cross-sectional study and serum samples were collected from 910 eligible Saudi male blood donors. DENV IgM and IgG antibodies were measured serologically by ELISA while viral serotypes were detected by a single step IVD CE certified multiplex RT-PCR kit. The overall prevalence was 39 and 5.5% for IgG+ and IgM+, respectively. There were 12 (1.3%) with exclusively IgM+, 317 (34.8%) exclusively IgG+ and 38 (4.2%) with dual IgM+/IgG+ donors. The overall prevalence was 3.2% (n = 29) and 2.3% (n = 21) for primary and secondary infections. PCR was positive in 5.5% (n = 50) and, DENV-2 (n = 24; 48%) was the most frequent serotype and was significantly higher than DENV-1 (20%; P = 0.02) and DENV-3 (2%; P = 0.1 × 10 -5 ) but not DENV-4 (30%; P = 0.2). There was no significant difference between both DENV-4 and DENV-1 (P = 0.4). The combination of the PCR and serology findings showed that 22 (2.4%) and 28 (3.1%) donors had primary and secondary viremic infections, respectively. The detected rates of DENV by PCR suggest a potential high risk of viral transmission by blood transfusion. To the best of our knowledge, this study is the first to report the detection of DENV-4 serotype in Saudi Arabia. More studies are required to measure the precise prevalence of DENV serotypes and their potential

Clinical and microbiological characterization of serotype 6D pneumococcal infections in South Korea.

PubMed

Cheong, Hee Jin; Song, Joon Young; Choi, Min Joo; Jeon, Ji Ho; Kang, Seong Hee; Jeong, Eun Joo; Noh, Ji Yun; Kim, Woo Joo

2016-08-01

The prevalence of Serotype 6D Streptococcus pneumoniae was reported relatively high in South Korea. Since the introduction of 7-valent pneumococcal conjugate vaccine (PCV7), serotype replacement was observed. This study was designed to better clarify genetic diversity of pneumococcal serotype 6D and its clinical characteristics after introduction of PCV7 in 2000. We performed serotyping analysis with 1298 pneumococcal isolates from clinical specimens in South Korea from 2004 to 2011. Multilocus sequence typing was performed, and minimal inhibitory concentration was determined for the available serotype 6D and nontypeable (NT) pneumococcal isolates during the 2006-2007 period. The proportion of serotype 6D pneumococci increased from 0.8% (2004-2007) to 2.9% (2008-2011) of all clinical pneumococcal isolates, accounting for 14.9% of serogroup 6 pneumococci in South Korea. NT pneumococci markedly increased to 13.3% during 2006-2007 in advance of the increase in serotype 6D. Among the 26 available serotype 6D pneumococcal isolates, ST282 was predominant (23 isolates, 88.5%). The STs of NT pneumococci (26 isolates) were diverse, but clonal complex 271 was the dominant clone. The oral penicillin non-susceptibility rate was 92.3% (24 among 26 isolates) for both serotype 6D and NT pneumococci. The ceftriaxone non-susceptibility rates of serotype 6D and NT pneumococci were 7.7% and 3.8%, respectively. ST228(6D) strain expanded, particularly among old adults with comorbidities in South Korea. Both antibiotic and PCV7 pressure might have contributed to the selective increase of NT and serotype 6D pneumococci. Copyright © 2016 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

[Isolation of Haemophilus influenzae serotypes from deep sites in sick children].

PubMed

Gatti, B M; Ramirez Gronda, G A; Etchevarría, M; Vescina, C M; Varea, A M; González Ayala, S E

2004-01-01

Haemophilus influenzae (Hi) is the causative agent of several human diseases such as sepsis, meningitis, celulitis, and osteoarthritis. We investigated the isolation of Hi serotypes from sterile sites in sick children. One hundred and seventy nine strains from 146 patients were studied, period 1996-2002, at the Microbiology Laboratory, Hospital de Niños Superiora Sor María Ludovica, Argentina. The serotype distribution was:1 a, 112 b,1 c,1 d, 4 e, 3 f y 24 no typable. Since the beginning of universal Hi b vaccination in 1998, we have observed the fast decrease of serotype b and a relative increase of other serotypes.

Yersinia pestis Orientalis in Remains of Ancient Plague Patients

PubMed Central

Drancourt, Michel; Signoli, Michel; Dang, La Vu; Bizot, Bruno; Roux, Véronique; Tzortzis, Stéfan

2007-01-01

Yersinia pestis DNA was recently detected in human remains from 2 ancient plague pandemics in France and Germany. We have now sequenced Y. pestis glpD gene in such remains, showing a 93-bp deletion specific for biotype Orientalis. These data show that only Orientalis type caused the 3 plague pandemics. PMID:17479906

Typing methods for the plague pathogen, Yersinia pestis.

PubMed

Lindler, Luther E

2009-01-01

Phenotypic and genotypic methodologies have been used to differentiate the etiological agent of plague, Yersinia pestis. Historically, phenotypic methods were used to place isolates into one of three biovars based on nitrate reduction and glycerol fermentation. Classification of Y. pestis into genetic subtypes is problematic due to the relative monomorphic nature of the pathogen. Resolution into groups is dependent on the number and types of loci used in the analysis. The last 5-10 years of research and analysis in the field of Y. pestis genotyping have resulted in a recognition by Western scientists that two basic types of Y. pestis exist. One type, considered to be classic strains that are able to cause human plague transmitted by the normal flea vector, is termed epidemic strains. The other type does not typically cause human infections by normal routes of infection, but is virulent for rodents and is termed endemic strains. Previous classification schemes used outside the Western hemisphere referred to these latter strains as Pestoides varieties of Y. pestis. Recent molecular analysis has definitely shown that both endemic and epidemic strains arose independently from a common Yersinia pseudotuberculosis ancestor. Currently, 11 major groups of Y. pestis are defined globally.

Antimicrobial susceptibility and serotypes of Actinobacillus (Haemophilus) pleuropneumoniae recovered from Missouri swine.

PubMed

Fales, W H; Morehouse, L G; Mittal, K R; Bean-Knudsen, C; Nelson, S L; Kintner, L D; Turk, J R; Turk, M A; Brown, T P; Shaw, D P

1989-01-01

The antimicrobial susceptibility of 73 Actinobacillus (Haemophilus) pleuropneumoniae isolates from swine in Missouri was determined with a microdilution minimal inhibitory concentration test system. Serotyping was accomplished by means of co-agglutination. Serotype 1 (39/73) and serotype 5 (30/73) were commonly found, whereas serotype 7 (4/73) was infrequently encountered. Most isolates (MIC90) were found susceptible to ampicillin (amoxicillin), cephalothin, penicillin, erythromycin, gentamicin, and kanamycin. Marked resistance was found with oxytetracycline, tylosin, and sulfadimethoxine. The data indicate that use of ampicillin (amoxicillin) or penicillin may correlate well with the favorable outcome of treatment.

Emerging Opportunities for Serotypes of Botulinum Neurotoxins

PubMed Central

Peng Chen, Zhongxing; Morris, J. Glenn; Rodriguez, Ramon L.; Shukla, Aparna Wagle; Tapia-Núñez, John; Okun, Michael S.

2012-01-01

Background: Two decades ago, botulinum neurotoxin (BoNT) type A was introduced to the commercial market. Subsequently, the toxin was approved by the FDA to address several neurological syndromes, involving muscle, nerve, and gland hyperactivity. These syndromes have typically been associated with abnormalities in cholinergic transmission. Despite the multiplicity of botulinal serotypes (designated as types A through G), therapeutic preparations are currently only available for BoNT types A and B. However, other BoNT serotypes are under study for possible clinical use and new clinical indications; Objective: To review the current research on botulinum neurotoxin serotypes A-G, and to analyze potential applications within basic science and clinical settings; Conclusions: The increasing understanding of botulinal neurotoxin pathophysiology, including the neurotoxin’s effects on specific neuronal populations, will help us in tailoring treatments for specific diagnoses, symptoms and patients. Scientists and clinicians should be aware of the full range of available data involving neurotoxin subtypes A-G. PMID:23202312

Serotype diversity of Streptococcus mutans and caries activity in children in Argentina.

PubMed

Carletto-Körber, F P; González-Ittig, R E; Jimenez, M G; Cornejo, L S

2015-09-01

The purpose of this study was to analyse the serotype distribution of S. mutans and their association with caries activity in school children from Córdoba, Argentina. Clinical examination was performed in 133 children. The dmft+DMFT and Significant Caries (SiC) indices were calculated to identify individuals with high caries activity. After DNA extractions of S. mutans strains, serotypes were determined by PCR amplifications. The median caries activity of each serotype group was compared using a non-parametric Kruskall-Wallis test. We obtained S. mutans strains from stimulated saliva of 94 children. The mean dmft+DMFT was 4.14 and the mean SiC index was 8.65. Serotype c was the most frequent (53.2%), followed by e (31.9%), f (8.5%) and k (6.4%). The comparison between the SiC and Non-Sic groups showed significant differences in the frequency of serotypes c and k. The median caries activity was non-significant in the different serotypes. The difference between the serotype frequencies detected in Argentina compared to those of other countries could be related with contrasting dietary habits. The results obtained in the present study would increase the knowledge about the epidemiology of dental caries in children from Argentina.

Different metabolic profiles of K1 serotype and non-serotype K1 and K2 Klebsiella pneumoniae isolates in oral infection mice model.

PubMed

Chen, Nan; Wang, Lin-Lin; Xue, Juan; Ma, Xiang-Bo; Zhao, Sheng; Rong, Rui-Xue; Li, Hong-Quan; Ding, Liang; Zheng, Ming-Zhi; Chen, Ying-Ying; Duan, Fei; Shen, Yue-Liang

2014-10-01

K1 or K2 serotype Klebsiella pneumoniae isolate caused clinical pyogenic liver abscess (KLA) infection is prevalent in many areas. It has been identified that K1 or K2 serotype K. pneumoniae isolates caused KLA infection in mice by oral inoculation. In our study, K1 serotype K. pneumoniae isolate Kp1002 with hypermucoviscosity (HV)-positive phenotype caused KLA infection in C57BL/6 mice by oral inoculation. Simultaneously, non-serotype K1 and K2 isolate Kp1014 with HV-negative phenotype failed to cause KLA infection in the same manner. It seems that gastrointestinal tract translocation is the pathway by which K1 or K2 serotype K. pneumoniae caused KLA infection. Liquid chromatography-tandem mass spectrometry was used to further analyze metabolic profile changes in mice with KLA infection. Data showed that after Kp1002 or Kp1014 oral inoculation, serum Phosphatidylcholine (PC) and Lysophosphatidylcholine (LPC) levels significantly changed in mice. Some PC and LPC molecules showed changes both in the Kp1002 KLA group and the Kp1014 no-KLA group compared with the control group. The level of 18:1/18:2-PC significantly changed in the Kp1002 KLA group compared with the control group, but showed no change between the Kp1014 no-KLA group and the control group. The level of 18:1/18:2-PC might have been particularly affected by KLA infection caused by K1 serotype K. pneumoniae Kp1002. It may be a potential biomarker for KLA infection. Copyright © 2014 Elsevier Ltd. All rights reserved.

Are risk factors associated with invasive pneumococcal disease according to different serotypes?

PubMed Central

Ciruela, Pilar; Soldevila, Núria; Selva, Laura; Hernández, Sergi; Garcia-Garcia, Juan Jose; Moraga, Fernando; de Sevilla, Mariona F.; Codina, Gemma; Planes, Ana Maria; Esteva, Cristina; Coll, Francis; Cardeñosa, Neus; Jordan, Iolanda; Batalla, Joan; Salleras, Luis; Muñoz-Almagro, Carmen; Domínguez, Angela

2013-01-01

The aim of this study was to investigate risk factors for the most common serotypes of invasive pneumococcal disease (IPD). A total of 293 IPD cases were analyzed in children aged 3–59 mo in a community with intermediate vaccination coverage with the 7-valent pneumococcal vaccine (PCV7). IPD cases were reviewed during 2007–2009 in two pediatric hospitals in Catalonia (Spain). A multivariate analysis using unconditional logistic regression was performed to estimate the adjusted odds ratio. PCV7 coverage was 45.4%. Pneumonia with empyema (64.5%) was the most frequent clinical manifestation. The most common serotypes were: serotype 1 (21.2%), 19A (16.0%), 3 (12.6%) and 7F/A (6.8%). 70.0% of serotypes found were included in the 13-valent conjugate vaccine (PCV13), 39.2% in the 10-valent conjugate vaccine and 8.1% in the PCV7. PCV7 was protective in IPD cases due to PCV7-serotypes (aOR: 0.15, 95% CI:0.04–0.55). Serotype 1 was positively associated with attending day care or school (aOR: 3.55, 95% CI: 1.21–10.38) and age 24–59 mo (aOR: 7.70, 95% CI:2.70–21.98). Serotype 19A was positively associated with respiratory infection in the previous month (aOR: 2.26, 95% CI: 1.03–4.94), non-penicillin susceptible IPD (aOR: 1.89, 95% CI:1.13–3.16) and negatively associated with age 24–59 mo (aOR: 0.19, 95% CI:0.09–0.41). Serotype 3 was positively associated with vaccination (aOR: 4.87, 95% CI:2.05–11.59). No factors were associated with serotype 7F/A. Vaccination with pneumococcal vaccines including more serotypes may reduce the risk of disease in our setting. PMID:23295982

Mutans streptococcal serotypes in children with gastroesophageal reflux disease.

PubMed

Hölttä, P; Aine, L; Mäki, M; Ruuska, T; Vuento, R; Ashorn, M; Alaluusua, S

1997-01-01

It has been suggested that vomiting acid gastric contents in bulimia might favor oral growth of Streptococcus sobrinus. We studied the colonization of Streptococcus sobrinus (serotypes g and d) and Streptococcus mutans (serotypes c, e and f) in sixteen children, ages five to fifteen years, who had suffered for four to eleven years from gastroesophageal reflux, another condition with recurrent acid regurgitation. Our aim was to find out if the prevalence of Streptococcus sobrinus would be higher also in this patient group. Mutants streptococci were detected in twelve out of sixteen (75 percent) study patients of the saliva samples cultured on MSB agar. For the Mutans streptococci positive children healthy controls were matched by salivary levels of mutans streptococci and age as closely as possible. From each child three to six isolates representing both Streptococcus mutans and Streptococcus sobrinus (n = 103) were serotyped by immunodiffusion method. The distribution of serotypes in the study/control group was: c: 7/10; e: 4/2; f: 0/1; g:3/2; d:0/0. One strain in the study group remained untypable. All patients infected with Streptococcus sobrinus were also infected with Streptococcus mutans. Our results indicate the great similarity in the distribution of ms serotypes in the gastroesophageal reflux children and their healthy controls. The data do not suggest that the acid regurgitation would have an influence on the prevalence of Streptococcus sobrinus.

Characterization of Atypical Isolates of Yersinia intermedia and Definition of Two New Biotypes▿ †

PubMed Central

Martin, Liliane; Leclercq, Alexandre; Savin, Cyril; Carniel, Elisabeth

2009-01-01

The species Yersinia intermedia is a member of the genus Yersinia which belongs to the Enterobacteriaceae family. This species is divided into eight biotypes, according to Brenner's biotyping scheme. This scheme relies on five tests (utilization of Simmons citrate and acid production from d-melibiose, d-raffinose, α-methyl-d-glucoside [αMG], and l-rhamnose). The collection of the French Yersinia Reference Laboratory (Institut Pasteur, Paris, France) contained 44 strains that were originally identified as Y. intermedia but whose characteristics did not fit into the biotyping scheme. These 44 strains were separated into two biochemical groups: variant 1 (positive for acid production from l-rhamnose and αMG and positive for Simmons citrate utlization) and variant 2 (positive for acid production from l-rhamnose and αMG). These atypical strains could correspond to new biotypes of Y. intermedia, to Y. frederiksenii strains having the atypical property of fermenting αMG, or to new Yersinia species. These strains did not exhibit growth or phenotypic properties different from those of Y. intermedia and Y. frederiksenii and did not harbor any of the virulence traits usually found in pathogenic species. DNA-DNA hybridizations performed between one strain each of variants 1 and 2 and the Y. intermedia and Y. frederiksenii type strains demonstrated that these variants do belong to the Y. intermedia species. We thus propose that Brenner's biotyping scheme be updated by adding two new biotypes: 9 (for variant 1) and 10 (for variant 2) to the species Y. intermedia. PMID:19494062

Isolation, propagation, and characterization of a second equine rotavirus serotype.

PubMed Central

Hoshino, Y; Wyatt, R G; Greenberg, H B; Kalica, A R; Flores, J; Kapikian, A Z

1983-01-01

A rotavirus designated strain H-2 was isolated in primary African green monkey kidney cells from a foal with diarrhea. This cell culture-adapted strain was found to be similar, if not identical, to simian rotavirus (strains MMU18006 and SA-11) and canine rotavirus (strain CU-1) and, in addition, demonstrated a one-way antigenic relationship with five human rotavirus strains (P, B, no. 14, no. 15, and YO) of the third human rotavirus serotype by the plaque reduction neutralization test. This is the fifth example of an animal rotavirus which shares serotypic specificity with a human rotavirus. The H-2 strain is distinct from the H-1 strain (Y. Hoshino et al., J. Clin. Microbiol., in press) of equine rotavirus not only in serotypic specificity by neutralization but also in subgroup specificity, hemagglutinating activity, and RNA electrophoretic migration pattern, thus establishing the existence of a second equine rotavirus serotype. This H-2 isolate is also distinct by neutralization from three other human rotavirus serotypes, 1 (Wa), 2 (DS-1), and 4 (St. Thomas no. 4), as well as bovine (NCDV), and porcine (OSU) rotaviruses. Images PMID:6309657

DNA Adenine Methylase Is Essential for Viability and Plays a Role in the Pathogenesis of Yersinia pseudotuberculosis and Vibrio cholerae

PubMed Central

Julio, Steven M.; Heithoff, Douglas M.; Provenzano, Daniele; Klose, Karl E.; Sinsheimer, Robert L.; Low, David A.; Mahan, Michael J.

2001-01-01

Salmonella strains that lack or overproduce DNA adenine methylase (Dam) elicit a protective immune response to different Salmonella species. To generate vaccines against other bacterial pathogens, the dam genes of Yersinia pseudotuberculosis and Vibrio cholerae were disrupted but found to be essential for viability. Overproduction of Dam significantly attenuated the virulence of these two pathogens, leading to, in Yersinia, the ectopic secretion of virulence proteins (Yersinia outer proteins) and a fully protective immune response in vaccinated hosts. Dysregulation of Dam activity may provide a means for the development of vaccines against varied bacterial pathogens. PMID:11705940

Imported dengue from 2013 Angola outbreak: Not just serotype 1 was detected.

PubMed

Abreu, Cândida; Silva-Pinto, André; Lazzara, Daniela; Sobrinho-Simões, Joana; Guimarães, João Tiago; Sarmento, António

2016-06-01

All the reports from Angola's 2013 dengue outbreak revealed serotype 1. However, previously dengue serotypes 1-4 have been reported in Africa and in 2014 serotype 4 was reported in Angola. To report dengue serotypes in patients returning from Angola during 2013 outbreak. Retrospective, cross-sectional study. We serotyped the dengue by an in house Polymerase Chain Reaction technique in randomly selected cases. From the 2013 Angola's dengue outbreak we treated 47 adult patients. None had history of past dengue. A combo kit test for dengue revealed positive NS1 antigen in 39 and IgM antibodies in 8. From 17 randomly patients tested by RNA Real Time-PCR, 11 were positive: 7 for DENV-1, 2 for DENV-2, 1 for DENV-3 (co-infected with DENV-1) and 1 for DENV-4. None had a complicated or fatal evolution. Unlike previous reports the 4 serotypes were detected, and this resulted in a different epidemiological situation, raising the risk of future outbreaks of severe dengue. Copyright © 2016 Elsevier B.V. All rights reserved.

[Serotype and phage type distribution of human Salmonella strains isolated in Spain, 1997-2001].

PubMed

Echeita, María Aurora; Aladueña, Ana María; Díez, Rosa; Arroyo, Margarita; Cerdán, Francisca; Gutiérrez, Rafaela; de la Fuente, Manuela; González-Sanz, Rubén; Herrera-León, Silvia; Usera, Miguel Angel

2005-03-01

Salmonellosis is one of the most frequent causes of gastroenteritis in Spain. Serotyping is the gold standard epidemiological marker for subdividing Salmonella spp. strains. A small number of serotypes are very frequently isolated, reducing the discriminatory power of serotyping. Thus, to increase our knowledge of Salmonella spp. epidemiology, additional epidemiological markers, such as phage typing, should be used for this purpose. Salmonella spp. strains of human origin sent to the Laboratorio Nacional de Referencia de Salmonella y Shigella (LNRSSE, Spanish Reference Laboratory for Salmonella and Shigella) between 1997 and 2001 were serotyped using conventional agglutination methods, and Enteritidis, Typhimurium, Hadar, Virchow and Typhi serotypes were additionally phage typed according to internationally-developed schemes. A total of 30,856 Salmonella spp. strains, isolated in the majority of Spanish Autonomous Communities, were analyzed. Enteritidis (51%) and Typhimurium (24%) were the most frequently isolated serotypes. The following were the most frequent serotype/phage type combinations: Enteritidis/PT1 (18%), Enteritidis/PT4 (15%), Enteritidis/PT6a (5%), Typhimurium/DT104 (5%) and Enteritidis/PT6 (3%). The serotype Enteritidis/PT1 showed the greatest increase over the period studied, from 11.61% in 1997 to 24.74% in 2001. A hierarchical typing approach for Salmonella spp., using serotyping coupled with phage typing allowed a higher level of discrimination among Salmonella serotypes. Application of this approach in epidemiological studies could be highly useful for early characterization of related strains.

Regulation of flagellum biosynthesis within the fish pathogen Yersinia ruckeri

USDA-ARS?s Scientific Manuscript database

Yersinia ruckeri, a Gram negative Enterobacterium, is the causative agent of enteric red mouth disease (ERM) within farmed rainbow trout (Oncorhynchus mykiss, Walbaum). There has been an increase of ERM outbreaks in previously vaccinated trout caused by a recently emerged, non-motile variant of Y. r...

Presence of foodborne pathogens, extended-spectrum β-lactamase -producing Enterobacteriaceae, and methicillin-resistant Staphylococcus aureus in slaughtered reindeer in northern Finland and Norway.

PubMed

Laaksonen, Sauli; Oksanen, Antti; Julmi, Jérôme; Zweifel, Claudio; Fredriksson-Ahomaa, Maria; Stephan, Roger

2017-01-03

Various food-producing animals were recognized in recent years as healthy carriers of bacterial pathogens causing human illness. In northern Fennoscandia, the husbandry of semi-domesticated reindeer (Rangifer tarandus tarandus) is a traditional livelihood and meat is the main product. This study determined the presence of selected foodborne pathogens, methicillin-resistant Staphylococcus aureus (MRSA), and extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae in healthy semi-domesticated reindeer at slaughter in northern Finland and Norway. All 470 reindeer fecal samples tested negative for Salmonella spp., whereas L. monocytogenes was detected in 3%, Yersinia spp. in 10%, and Shiga toxins genes (stx1 and/or stx2) in 33% of the samples. Listeria monocytogenes isolates belonged to the serotype 1/2a (14/15) and 4b, Yersinia spp. were identified mainly as Y. kristensenii (30/46) and Y. enterocolitica (8/46), and stx2 predominated among the Shiga toxin genes (stx2 alone or in combination with stx1 was found in 25% of the samples). With regard to the frequency and distribution of stx1/stx2, striking differences were evident among the 10 different areas of origin. Hence, reindeer could constitute a reservoir for Shiga toxin-producing E. coli (STEC), but strain isolation and characterization is required for verification purposes and to assess the potential human pathogenicity of strains. On the other hand, the favorable antibiotic resistance profiles (only 5% of 95 E. coli isolates were resistant to one or more of the tested antibiotics) and the absence of MRSA and ESBL-producing Enterobacteriaceae (when applying selective methods) suggest only a limited risk of transmission to humans. Healthy semi-domesticated reindeer in northern Finland and Norway can be carriers of certain bacterial foodborne pathogens. Strict compliance with good hygiene practices during any step of slaughter (in particular during dehiding and evisceration) is therefore of central

A DNA microarray-based assay to detect dual infection with two dengue virus serotypes.

PubMed

Díaz-Badillo, Alvaro; Muñoz, María de Lourdes; Perez-Ramirez, Gerardo; Altuzar, Victor; Burgueño, Juan; Mendoza-Alvarez, Julio G; Martínez-Muñoz, Jorge P; Cisneros, Alejandro; Navarrete-Espinosa, Joel; Sanchez-Sinencio, Feliciano

2014-04-25

Here; we have described and tested a microarray based-method for the screening of dengue virus (DENV) serotypes. This DNA microarray assay is specific and sensitive and can detect dual infections with two dengue virus serotypes and single-serotype infections. Other methodologies may underestimate samples containing more than one serotype. This technology can be used to discriminate between the four DENV serotypes. Single-stranded DNA targets were covalently attached to glass slides and hybridised with specific labelled probes. DENV isolates and dengue samples were used to evaluate microarray performance. Our results demonstrate that the probes hybridized specifically to DENV serotypes; with no detection of unspecific signals. This finding provides evidence that specific probes can effectively identify single and double infections in DENV samples.

A DNA Microarray-Based Assay to Detect Dual Infection with Two Dengue Virus Serotypes

PubMed Central

Díaz-Badillo, Alvaro; de Lourdes Muñoz, María; Perez-Ramirez, Gerardo; Altuzar, Victor; Burgueño, Juan; Mendoza-Alvarez, Julio G.; Martínez-Muñoz, Jorge P.; Cisneros, Alejandro; Navarrete-Espinosa, Joel; Sanchez-Sinencio, Feliciano

2014-01-01

Here; we have described and tested a microarray based-method for the screening of dengue virus (DENV) serotypes. This DNA microarray assay is specific and sensitive and can detect dual infections with two dengue virus serotypes and single-serotype infections. Other methodologies may underestimate samples containing more than one serotype. This technology can be used to discriminate between the four DENV serotypes. Single-stranded DNA targets were covalently attached to glass slides and hybridised with specific labelled probes. DENV isolates and dengue samples were used to evaluate microarray performance. Our results demonstrate that the probes hybridized specifically to DENV serotypes; with no detection of unspecific signals. This finding provides evidence that specific probes can effectively identify single and double infections in DENV samples. PMID:24776933

Novel genetic tools for diaminopimelic acid selection in virulence studies of Yersinia pestis.

PubMed

Bland, David M; Eisele, Nicholas A; Keleher, Lauren L; Anderson, Paul E; Anderson, Deborah M

2011-03-02

Molecular studies of bacterial virulence are enhanced by expression of recombinant DNA during infection to allow complementation of mutants and expression of reporter proteins in vivo. For highly pathogenic bacteria, such as Yersinia pestis, these studies are currently limited because deliberate introduction of antibiotic resistance is restricted to those few which are not human treatment options. In this work, we report the development of alternatives to antibiotics as tools for host-pathogen research during Yersinia pestis infections focusing on the diaminopimelic acid (DAP) pathway, a requirement for cell wall synthesis in eubacteria. We generated a mutation in the dapA-nlpB(dapX) operon of Yersinia pestis KIM D27 and CO92 which eliminated the expression of both genes. The resulting strains were auxotrophic for diaminopimelic acid and this phenotype was complemented in trans by expressing dapA in single and multi-copy. In vivo, we found that plasmids derived from the p15a replicon were cured without selection, while selection for DAP enhanced stability without detectable loss of any of the three resident virulence plasmids. The dapAX mutation rendered Y. pestis avirulent in mouse models of bubonic and septicemic plague which could be complemented when dapAX was inserted in single or multi-copy, restoring development of disease that was indistinguishable from the wild type parent strain. We further identified a high level, constitutive promoter in Y. pestis that could be used to drive expression of fluorescent reporters in dapAX strains that had minimal impact to virulence in mouse models while enabling sensitive detection of bacteria during infection. Thus, diaminopimelic acid selection for single or multi-copy genetic systems in Yersinia pestis offers an improved alternative to antibiotics for in vivo studies that causes minimal disruption to virulence.

Novel PCR-Restriction Fragment Length Polymorphism Method for Determining Serotypes or Serogroups of Streptococcus pneumoniae Isolates

PubMed Central

Batt, Sarah L.; Charalambous, Bambos M.; McHugh, Timothy D.; Martin, Siobhan; Gillespie, Stephen H.

2005-01-01

Serotyping Streptococcus pneumoniae is a technique generally confined to reference laboratories, as purchasing pneumococcal antisera is a huge investment. Many attempts have been made to modify serological agglutination techniques to make them more accessible, and more recently developments in serotyping have focused on molecular techniques. This paper describes a PCR assay which amplifies the entire capsulation locus between dexB and aliA. Amplicons are digested to produce serotype-specific patterns. We have shown, using 81 epidemiologically unrelated strains representing 46 different serotypes, that the patterns correlate with a 90 to 100% similarity range for the same serotype or serogroup. Prospective testing of 73 isolates of unknown serotype confirmed reliable serotype attribution, and serotype profiles are reproducible on repeated testing. Once our database contains all 90 serotypes, this technique should be fully portable, cost-effective, and useful in any laboratory with sufficient molecular experience. PMID:15956380

Capsular Serotype and Antibiotic Resistance of Streptococcus pneumoniae Isolates in Two Chilean Cities

PubMed Central

Inostroza, Jaime; Trucco, Olivia; Prado, Valeria; Vinet, Ana Maria; Retamal, Gloria; Ossa, Gonzalo; Facklam, Richard R.; Sorensen, Ricardo U.

1998-01-01

We compared the incidence of nasopharyngeal colonization by Streptococcus pneumoniae, the serotypes causing mucosal and invasive diseases, and the antibiotic resistance of these strains in patients admitted to three large hospitals and children attending day care centers in two Chilean cities (Santiago and Temuco). The populations in both cities were similar in ethnic background, socioeconomic status, family size, and access to medical care. Significant differences in nasopharyngeal colonization rates, in serotypes causing infections, and in antibiotic resistance were found between the two cities. In children 0 to 2 years of age, 42% were colonized with S. pneumoniae in Santiago compared to 14% in Temuco. A total of 41 serotypes were identified in both Chilean cities studied. Six serotypes were found only in Santiago; 14 serotypes were found only in Temuco. Antibiotic-resistant serotypes 6A, 6B, 14, 19F, and 23F were detected only in Santiago. We show that important differences in the incidence of nasopharyngeal carriage, infection, and S. pneumoniae serotypes can exist in similar populations in different areas of the same country. Our findings are relevant for prevention strategies, antibiotic usage, and vaccine design. PMID:9521139

Complicated meningitis caused by a rare serotype of Haemophilus influenzae in Portugal.

PubMed

Calado, Rita; Betencourt, Célia; Gonçalves, Helder; Cristino, Nuno; Calhau, Paulo; Lavado, Paula Bajanca

2011-01-01

We report a case of meningitis due to Haemophilus influenzae serotype d strain in an infant. As far as we know, this is the first report of a serotype d strain, responsible for childhood invasive disease in Europe, demonstrating an emerging of H. influenzae non-b serotype, in the post-vaccination era. Copyright © 2011 Elsevier Inc. All rights reserved.

Establishment and localization of mixtures of Streptococcus mutans serotypes in the oral cavity of the rat.

PubMed

Huis in 't Veld, J H; Drost, J S; Havenaar, R

1982-10-01

The colonization of S. mutans serotypes on different tooth surfaces of the rat was investigated. Fissures appeared to be the main habitat. In the presence of a serotype c strain, S. mutans serotype d could only be established when sucrose-containing diets were supplied. However, the serotype c strain was always present in higher proportions. The production of a bacteriocin for which the serotype d strain was sensitive appeared to be responsible for the observed predominance of the serotype c strain.

[Campylobacter jejuni infections in slaughterhouse workers].

PubMed

Mancinelli, S; Riccardi, F; Santi, A L; Palombi, L; Marazzi, M C

1988-01-01

Complement fixing (C.F.) antibodies to Campylobacter jejuni were detected in 83 slaughterhouse workers and 83 blood donors. Workers were aged 18-65 years (mean, 41.7 +/- 12.3) and had worked in the slaughterhouse for 2-40 years (mean, 17.5 +/- 5.1). C.F. antibodies were detected according to Mosimann's method and by including five antigens: Campylobacter jejuni, Yersinia enterocolitica types 03 and 09, Yersinia pseudotuberculosis and Brucella. Positive titers were found in 12.1% of workers and in 2.4% of control subjects (p less than 0.01); values ranged from 1:10 to 1:40. Frequent and close contact with animals or their products was significantly associated with seropositivity. No association was found with the time of employment. Sixty per cent of seropositive workers referred rheumatological symptoms. These findings confirm that slaughterhouse workers exposed to potential sources of C. jejuni have elevated titers of antibodies. Attention has, therefore, to be focused on breaking the chain of transmission as a means of control.

Serological Prevalence of Enteropathogenic Yersinia spp. in Pigs and Wild Boars from Different Production Systems in the Moravian Region, Czech Republic.

PubMed

Lorencova, Alena; Babak, Vladimir; Lamka, Jiri

2016-05-01

Human yersiniosis caused by pathogenic Yersinia spp. is one of the most common reported zoonoses in the European Union and pigs are considered as the major reservoir of these bacteria. Serological testing represents a suitable method to obtain information about the prevalence of enteropathogenic Yersinia spp. in food animals. The prevalence of antibodies against enteropathogenic Yersinia spp. was studied in 319 slaughtered pigs and 135 wild boars from different production systems in the Moravian region (Czech Republic) using a commercially available ELISA test (an apparent prevalence). The seroprevalence was significantly associated with the type of breeding system, with the lowest seroprevalence being observed in household-raised pigs (13/29, 44.8%). No significant difference between the prevalence of anti-Yersinia antibodies in conventional (146/180, 81.1%) and organic pigs (92/110, 83.6%) was found. Antibodies were found in 65.9% (89/135) of wild boars without a significant difference between adult (23/41, 56.1%) and young (66/94, 70.2%) animals. Seropositivity was significantly higher in domestic (251/319, 78.7% in total) compared to feral pigs. A Bayesian approach taking into account the sensitivity and specificity of the ELISA test was used to estimate the true prevalence of anti-Yersinia antibodies in pigs and wild boars. According to our results, domestic pigs and wild boars proved to be an important reservoir of enteropathogenic Yersinia in the Czech Republic. Attention should be paid to good hygienic practice during slaughtering and handling of meat to prevent meat contamination and subsequently human infection.

Epigenetic regulation of serotype expression antagonizes transcriptome dynamics in Paramecium tetraurelia

PubMed Central

Cheaib, Miriam; Dehghani Amirabad, Azim; Nordström, Karl J. V.; Schulz, Marcel H.; Simon, Martin

2015-01-01

Phenotypic variation of a single genotype is achieved by alterations in gene expression patterns. Regulation of such alterations depends on their time scale, where short-time adaptations differ from permanently established gene expression patterns maintained by epigenetic mechanisms. In the ciliate Paramecium, serotypes were described for an epigenetically controlled gene expression pattern of an individual multigene family. Paradoxically, individual serotypes can be triggered in Paramecium by alternating environments but are then stabilized by epigenetic mechanisms, thus raising the question to which extend their expression follows environmental stimuli. To characterize environmental adaptation in the context of epigenetically controlled serotype expression, we used RNA-seq to characterize transcriptomes of serotype pure cultures. The resulting vegetative transcriptome resource is first analysed for genes involved in the adaptive response to the altered environment. Secondly, we identified groups of genes that do not follow the adaptive response but show co-regulation with the epigenetically controlled serotype system, suggesting that their gene expression pattern becomes manifested by similar mechanisms. In our experimental set-up, serotype expression and the entire group of co-regulated genes were stable among environmental changes and only heat-shock genes altered expression of these gene groups. The data suggest that the maintenance of these gene expression patterns in a lineage represents epigenetically controlled robustness counteracting short-time adaptation processes. PMID:26231545

Serotype Distribution and Antimicrobial Resistance of Streptococcus pneumoniae Isolates from Pediatric Patients in Singapore

PubMed Central

Soh, Shirlena Wee-Ling; Poh, Chit Laa; Lin, Raymond V. Tzer Pin

2000-01-01

One hundred eighty Streptococcus pneumoniae strains isolated from children at a pediatric hospital in Singapore from 1997 to 1999 were serotyped and their antimicrobial susceptibility patterns were determined. Sixty-three percent of the isolates were resistant to penicillin. Significantly large numbers of the strains investigated were resistant to trimethoprim-sulfamethoxazole (87.8%), tetracycline (71.7%), erythromycin (67.8%), and chloramphenicol (40%). Penicillin and multidrug resistance was mostly associated with the frequently isolated S. pneumoniae isolates of serotypes (serotypes 19F, 23F, 6B, and 14). Isolates of serotype 19F, the serotype most commonly encountered in Singapore (41.1%), had the highest prevalence of penicillin (78.4%) and multidrug resistance (94.6%). Most of the invasive S. pneumoniae isolates (8 of 17; 47.1%) were of serotype 14. PMID:10898701

Structural elucidation of the O-antigen of the Shigella flexneri provisional serotype 88-893: structural and serological similarities with S. flexneri provisional serotype Y394 (1c).

PubMed

Foster, R A; Carlin, N I A; Majcher, M; Tabor, H; Ng, L-K; Widmalm, G

2011-05-01

The structure of the repeating unit of the O-antigen polysaccharide from Shigella flexneri provisional serotype 88-893 has been determined. (1)H and (13)C NMR spectroscopy as well as 2D NMR experiments were employed to elucidate the structure. The carbohydrate part of the hexasaccharide repeating unit is identical to the previously elucidated structure of the O-polysaccharide from S. flexneri prov. serotype Y394. The O-antigen of S. flexneri prov. serotype 88-893 carries 0.7 mol O-acetyl group per repeating unit located at O-2 of the 3-substituted rhamnosyl residue, as identified by H2BC and BS-CT-HMBC NMR experiments. The O-antigen polysaccharide is composed of hexasaccharide repeating units with the following structure: →2)-α-L-Rhap-(1→2)-α-L-Rhap-(1→3)-α-L-Rhap2Ac-(1→3)[α-D-Glcp-(1→2)-α-D-Glcp-(1→4)]-β-D-GlcpNAc-(1→. Serological studies showed that type antigens for the two provisional serotypes are identical; in addition 88-893 expresses S. flexneri group factor 6 antigen. We propose that provisional serotypes Y394 and 88-893 be designated as two new serotypes 7a and 7b, respectively, in the S. flexneri typing scheme. Copyright © 2011 Elsevier Ltd. All rights reserved.

Disinfectant susceptibility of different Salmonella serotypes isolated from chicken and egg production chains.

PubMed

Long, M; Lai, H; Deng, W; Zhou, K; Li, B; Liu, S; Fan, L; Wang, H; Zou, L

2016-09-01

The study aimed to serotype the Salmonella isolates recovered from chicken and egg production chains, and to investigate the disinfectant resistance phenotypes and genotypes of these isolates. The Salmonella isolates were serotyped, and the minimal inhibitory concentrations (MICs) of disinfectants were determined. Results showed that the Salmonella isolates recovered from both chains were diverse, and the serotypes in each part of the production chain and between the two production chains were significantly different. In the chicken production chain, 19 different serotypes were recovered, while only five serotypes were found in the egg production chain. The isolates showed a high susceptibility to didecyldimethylammonium bromide (DDAB) but a low susceptibility to benzalkonium chloride (BC), benzalkonium bromide (BAB) and chlorhexidine (CHX). Salmonella Enteritidis and Salmonella Typhimurium were more resistant to BC and BAB. The qacEΔ1 and qacF resistance genes were detected in 26·7 and 7·7% of the isolates respectively. The qacEΔ1 gene was frequently found in Salmonella Derby and Salm. Enteritidis (P < 0·05). Our findings indicated that Salmonella was commonly present in both chains, and could serve as a critical vector in spreading disinfectant resistance associated with different serotypes. This study first demonstrated disinfectant resistance phenotypes and genotypes of serotyped Salmonella. The study highlights the need for monitoring the disinfectant resistance varied in different Salmonella serotypes. © 2016 The Society for Applied Microbiology.

Rapid identification of Yersinia pestis and Brucella melitensis by chip-based continuous flow PCR

NASA Astrophysics Data System (ADS)

Dietzsch, Michael; Hlawatsch, Nadine; Melzer, Falk; Tomaso, Herbert; Gärtner, Claudia; Neubauer, Heinrich

2012-06-01

To combat the threat of biological agents like Yersinia pestis and Brucella melitensis in bioterroristic scenarios requires fast, easy-to-use and safe identification systems. In this study we describe a system for rapid amplification of specific genetic markers for the identification of Yersinia pestis and Brucella melitensis. Using chip based PCR and continuous flow technology we were able to amplify the targets simultaneously with a 2-step reaction profile within 20 minutes. The subsequent analysis of amplified fragments by standard gel electrophoresis requires another 45 minutes. We were able to detect both pathogens within 75 minutes being much faster than most other nucleic acid amplification technologies.

Chlorhexidine susceptibilities of mutans streptococcal serotypes and ribotypes.

PubMed

Grönroos, L; Mättö, J; Saarela, M; Luoma, A R; Luoma, H; Jousimies-Somer, H; Pyhälä, L; Asikainen, S; Alaluusua, S

1995-04-01

The susceptibilities of 379 clinical mutans streptococcal isolates to chlorhexidine (CHX) were tested by agar dilution according to the standards of the National Committee for Clinical Laboratory Standards. Isolates were obtained from saliva samples of 34 young mothers who had high or moderate salivary levels of mutans streptococci at baseline. Samples were collected on three occasions, before childbirth, when each child was 6 months old, and 1 year later. Of these isolates, 50% were inhibited at 1 microgram of CHX per ml, 90% were inhibited at 2.0 micrograms/ml, and all were inhibited at 4.0 micrograms/ml. The MICs for Streptococcus mutans isolates (serotypes c, e, and f) were lower than those for Streptococcus sobrinus isolates (serotypes d and g). In some subjects, the MICs for isolates of the same serotype were different. This phenomenon was studied by ribotyping isolates (n = 45) from selected subjects (n = 7). It was found that if there were intraindividual differences in the MICs for isolates of the same serotype, then the ribotypes of these isolates were different. In order to decrease the mutans streptococcal infection risk for children, 24 mothers (test group) brushed their teeth periodically with a gel that contained 0.3% CHX digluconate and 0.2% NaF, pH 5.8, between the second and third sampling occasions. The gel was used twice a day for the first 10 days of each month. Development of resistant strains during CHX-NaF gel use was not detected. The serotype distribution of isolates from the test group after 1 year of periodic CHX-NaF gel use did not differ from that at baseline. Periodic CHX-NaF gel brushing did not lead to lower salivary mutans streptococcal counts.

Chlorhexidine susceptibilities of mutans streptococcal serotypes and ribotypes.

PubMed Central

Grönroos, L; Mättö, J; Saarela, M; Luoma, A R; Luoma, H; Jousimies-Somer, H; Pyhälä, L; Asikainen, S; Alaluusua, S

1995-01-01

The susceptibilities of 379 clinical mutans streptococcal isolates to chlorhexidine (CHX) were tested by agar dilution according to the standards of the National Committee for Clinical Laboratory Standards. Isolates were obtained from saliva samples of 34 young mothers who had high or moderate salivary levels of mutans streptococci at baseline. Samples were collected on three occasions, before childbirth, when each child was 6 months old, and 1 year later. Of these isolates, 50% were inhibited at 1 microgram of CHX per ml, 90% were inhibited at 2.0 micrograms/ml, and all were inhibited at 4.0 micrograms/ml. The MICs for Streptococcus mutans isolates (serotypes c, e, and f) were lower than those for Streptococcus sobrinus isolates (serotypes d and g). In some subjects, the MICs for isolates of the same serotype were different. This phenomenon was studied by ribotyping isolates (n = 45) from selected subjects (n = 7). It was found that if there were intraindividual differences in the MICs for isolates of the same serotype, then the ribotypes of these isolates were different. In order to decrease the mutans streptococcal infection risk for children, 24 mothers (test group) brushed their teeth periodically with a gel that contained 0.3% CHX digluconate and 0.2% NaF, pH 5.8, between the second and third sampling occasions. The gel was used twice a day for the first 10 days of each month. Development of resistant strains during CHX-NaF gel use was not detected. The serotype distribution of isolates from the test group after 1 year of periodic CHX-NaF gel use did not differ from that at baseline. Periodic CHX-NaF gel brushing did not lead to lower salivary mutans streptococcal counts. PMID:7785991

Serotype distribution of Streptococcus pneumoniae in children with invasive diseases in Turkey: 2008-2014.

PubMed

Ceyhan, Mehmet; Ozsurekci, Yasemin; Gürler, Nezahat; Öksüz, Lütfiye; Aydemir, Sohret; Ozkan, Sengul; Yuksekkaya, Serife; Keser Emiroglu, Melike; Gültekin, Meral; Yaman, Akgün; Kiremitci, Abdurrahman; Yanık, Keramettin; Karli, Arzu; Ozcinar, Hatice; Aydin, Faruk; Bayramoglu, Gulcin; Zer, Yasemin; Gulay, Zeynep; Gayyurhan, Efgan Dogan; Gül, Mustafa; Özakın, Cüneyt; Güdücüoğlu, Hüseyin; Perçin, Duygu; Akpolat, Nezahat; Ozturk, Candan; Camcıoğlu, Yıldız; Karadağ Öncel, Eda; Çelik, Melda; Şanal, Laser; Uslu, Hakan

2016-01-01

Successful vaccination policies for protection from invasive pneumococcal diseases (IPD) dependent on determination of the exact serotype distribution in each country. We aimed to identify serotypes of pneumococcal strains causing IPD in children in Turkey and emphasize the change in the serotypes before and after vaccination with 7-valent pneumococcal conjugate vaccine (PCV-7) was included and PCV-13 was newly changed in Turkish National Immunization Program. Streptococcus pneumoniae strains were isolated at 22 different hospitals of Turkey, which provide healthcare services to approximately 65% of the Turkish population. Of the 335 diagnosed cases with S. pneumoniae over the whole period of 2008-2014, the most common vaccine serotypes were 19F (15.8%), 6B (5.9%), 14 (5.9%), and 3 (5.9%). During the first 5 y of age, which is the target population for vaccination, the potential serotype coverage ranged from 57.5 % to 36.8%, from 65.0% to 44.7%, and from 77.4% to 60.5% for PCV-7, PCV-10, and PCV-13 in 2008-2014, respectively. The ratio of non-vaccine serotypes was 27.2% in 2008-2010 whereas was 37.6% in 2011-2014 (p=0.045). S. penumoniae serotypes was less non-susceptible to penicillin as compared to our previous results (33.7 vs 16.5 %, p=0.001). The reduction of those serotype coverage in years may be attributed to increasing vaccinated children in Turkey and the increasing non-vaccine serotype may be explained by serotype replacement. Our ongoing IPD surveillance is a significant source of information for the decision-making processes on pneumococcal vaccination.

Variations in the radiation sensitivity of foodborne pathogens associated with complex ready-to-eat food products

NASA Astrophysics Data System (ADS)

Sommers, Christopher H.; Boyd, Glenn

2006-07-01

Foodborne illness outbreaks and product recalls are occasionally associated with ready-to-eat (RTE) sandwiches and other "heat and eat" multi-component RTE products. Ionizing radiation can inactivate foodborne pathogens on meat and poultry, fruits and vegetables, seafood, and RTE meat products. However, less data are available on the ability of low-dose ionizing radiation, doses under 5 kGy typically used for pasteurization purposes, to inactivate pathogenic bacteria on complex multi-component food products. In this study, the efficacy of ionizing radiation to inactivate Salmonella spp., Listeria monocytogenes, Staphylococcus aureus, Escherichia coli O157:H7, and Yersinia enterocolitica on RTE foods including a "frankfurter on a roll", a "beef cheeseburger on a bun" and a "vegetarian cheeseburger on a bun" was investigated. The average D-10 values, the radiation dose needed to inactivate 1 log 10 of pathogen, by bacterium species, were 0.61, 0.54, 0.47, 0.36 and 0.15 kGy for Salmonella spp., S. aureus, L. monocytogenes, E. coli O157:H7, and Y. enterocolitica, respectively when inoculated onto the three product types. These results indicate that irradiation may be an effective means for inactivating common foodborne pathogens including Salmonella spp, S. aureus, L. monocytogenes, E. coli O157:H7 and Y. enterocolitica in complex RTE food products such as 'heat and eat" sandwich products.

The genetic organization of the capsular polysaccharide biosynthesis region of Actinobacillus pleuropneumoniae serotype 14

PubMed Central

ITO, Hiroya

2015-01-01

The genetic organization of the gene involved in the capsular polysaccharide (CPS) biosynthesis of Actinobacillus pleuropneumoniae serotype 14 has been determined. The DNA region for the CPS biosynthesis of serotype 14 (cps14) comprised 9 open reading frames, designated as cps14AB1B2B3CDEFG genes, encoding Cps14A to Cps14G protein, respectively. Cps14A was similar to CpsA of A. pleuropneumoniae serotypes 1, 4 and 12; the Cps14B1 and Cps14B2 were similar to CpsB of A. pleuropneumoniae serotypes 1, 4 and 12, suggesting that CPS structure of A. pleuropneumoniae serotype 14 would belong to Group I including A. pleuropneumoniae serotypes 1, 4, 12 and 15. Surprisingly, the overall nucleotide sequence, deduced amino acid sequence, and the genetic organization of the cps14 were nearly identical to those of Actinobacillus suis. This study will provide the molecular basic knowledge for development of diagnostics and vaccine of A. pleuropneumoniae serotype 14. PMID:25648373

The genetic organization of the capsular polysaccharide biosynthesis region of Actinobacillus pleuropneumoniae serotype 15

PubMed Central

ITO, Hiroya; SUEYOSHI, Masuo

2014-01-01

Nucleotide sequence determination and analysis of the cps gene involved in the capsular polysaccharide biosynthesis of Actinobacillus pleuropneumoniae serotype 15 revealed the presence of three open reading frames, designated as cps15ABC genes. At the protein level, Cps15A and Cps15B showed considerably high homology to CpsA (67.0 to 68.7%) and CpsB (31.7 to 36.8%), respectively, of A. pleuropneumoniae serotypes 1, 4 and 12, revealing the common genetic organization of the cps among serotypes 1, 4, 12 and 15. However, Cps15C showed no homology to any proteins of A. pleuropneumoniae serotypes, indicating that cps15C may be specific to serotype 15. This study will provide the basic molecular knowledge necessary for the development of diagnostics and a vaccine for A. pleuropneumoniae serotype 15. PMID:25502540

Comparison of Toxicological Properties of Botulinum Neurotoxin Serotypes A and B in Mice

USDA-ARS?s Scientific Manuscript database

Botulinum neurotoxins (BoNTs) are among the most toxic biological toxins for humans. Of the seven known serotypes (A-G) of BoNT, serotypes A, B and E cause most of the human foodborne intoxications. In this study, we compared the toxicological properties of BoNT serotype A and B holotoxins and compl...

Comparison of Capsular Genes of Streptococcus pneumoniae Serotype 6A, 6B, 6C, and 6D Isolates▿

PubMed Central

Song, Jae-Hoon; Baek, Jin Yang; Ko, Kwan Soo

2011-01-01

Recently, Streptococcus pneumoniae serotypes 6C and 6D have been identified. It is thought that they emerged by the replacement of wciNβ in the capsular loci of serotypes 6A and 6B, respectively. However, their evolution has not been unveiled yet. To investigate the evolution of four serotypes of S. pneumoniae serogroup 6, four genes of the capsular polysaccharide synthesis (cps) locus, wchA, wciN, wciO, and wciP, of isolates of S. pneumoniae serotypes 6A, 6B, 6C, and 6D were sequenced. Multilocus sequence typing (MLST) was performed to investigate their genetic backgrounds. The wchA gene of serotype 6C and 6D isolates was distinct from that of serotype 6A and 6B isolates, which may suggest cotransfer of wchA with wciNβ. Otherwise, serotypes 6C and 6D displayed different genetic backgrounds from serotypes 6A and 6B, which was suggested by MLST analysis. In addition, serotype 6C isolates showed distinct wciP polymorphisms from other serotypes, which also indicated that serotype 6C had not recently originated from serotype 6A. Although serotype 6D shared the same amino acid polymorphisms of wciO with serotype 6B, wciP of serotype 6D differed from that of serotype 6B. The data indicate the implausibility of the scenario of a recent emergence of the cps locus of serotype 6D by genetic recombination between serotypes 6B and 6C. In addition, five serotype 6A and 6B isolates (6X group) displayed cps loci distinct from those of other isolates. The cps locus homogeneity and similar sequence types in MLST analysis suggest that most of the 6X group of isolates originated from the same ancestor and that the entire cps locus might have recently been transferred from an unknown origin. Serotype 6B isolates showed two or more cps locus subtypes, indicating a recombination-mediated mosaic structure of the cps locus of serotype 6B. The collective data favor the emergence of cps loci of serotypes 6A, 6B, 6C, and 6D by complicated recombination. PMID:21411593

Age-Specific Cluster of Cases of Serotype 1 Streptococcus pneumoniae Carriage in Remote Indigenous Communities in Australia ▿

PubMed Central

Smith-Vaughan, H.; Marsh, R.; Mackenzie, G.; Fisher, J.; Morris, P. S.; Hare, K.; McCallum, G.; Binks, M.; Murphy, D.; Lum, G.; Cook, H.; Krause, V.; Jacups, S.; Leach, A. J.

2009-01-01

Seven-valent pneumococcal conjugate vaccination commenced in 2001 for Australian indigenous infants. Pneumococcal carriage surveillance detected substantial replacement with nonvaccine serotypes and a cluster of serotype 1 carriage. Our aim was to review Streptococcus pneumoniae serotype 1 carriage and invasive pneumococcal disease (IPD) data for this population and to analyze serotype 1 isolates. Carriage data were collected between 1992 and 2004 in the Darwin region, one of the five regions in the Northern Territory. Carriage data were also collected in 2003 and 2005 from four regions in the Northern Territory. Twenty-six cases of serotype 1 IPD were reported from 1994 to 2007 in the Northern Territory. Forty-four isolates were analyzed by BOX typing and 11 by multilocus sequence typing. In the Darwin region, 26 children were reported carrying serotype 1 (ST227) in 2002 but not during later surveillance. Scattered cases of serotype 1 carriage were noted in two other regions. Cocolonization of serotype 1 with other pneumococcal serotypes was common (34% serotype 1-positive swabs). In conclusion, pneumococcal carriage studies detected intermittent serotype 1 carriage and an ST227 cluster in children in indigenous communities in the Northern Territory of Australia. There was no apparent increase in serotype 1 IPD during this time. The rate of serotype 1 cocolonization with other pneumococcal serotypes suggests that carriage of this serotype may be underestimated. PMID:19091995

Innate immune response during Yersinia infection: critical modulation of cell death mechanisms through phagocyte activation.

PubMed

Bergsbaken, Tessa; Cookson, Brad T

2009-11-01

Yersinia pestis, the etiological agent of plague, is one of the most deadly pathogens on our planet. This organism shares important attributes with its ancestral progenitor, Yersinia pseudotuberculosis, including a 70-kb virulence plasmid, lymphotropism during growth in the mammalian host, and killing of host macrophages. Infections with both organisms are biphasic, where bacterial replication occurs initially with little inflammation, followed by phagocyte influx, inflammatory cytokine production, and tissue necrosis. During infection, plasmid-encoded attributes facilitate bacterial-induced macrophage death, which results from two distinct processes and corresponds to the inflammatory crescendo observed in vivo: Naïve cells die by apoptosis (noninflammatory), and later in infection, activated macrophages die by pyroptosis (inflammatory). The significance of this redirected cell death for the host is underscored by the importance of phagocyte activation for immunity to Yersinia and the protective role of pyroptosis during host responses to anthrax lethal toxin and infections with Francisella, Legionella, Pseudomonas, and Salmonella. The similarities of Y. pestis and Y. pseudotuberculosis, including conserved, plasmid-encoded functions inducing at least two distinct mechanisms of cell death, indicate that comparative studies are revealing about their critical pathogenic mechanism(s) and host innate immune responses during infection. Validation of this idea and evidence of similar interactions with the host immune system are provided by Y. pseudotuberculosis-priming, cross-protective immunity against Y. pestis. Despite these insights, additional studies indicate much remains to be understood concerning effective host responses against Yersinia, including chromosomally encoded attributes that also contribute to bacterial evasion and modulation of innate and adaptive immune responses.

Complete genome sequence of Streptococcus mutans GS-5, a serotype c strain.

PubMed

Biswas, Saswati; Biswas, Indranil

2012-09-01

Streptococcus mutans, a principal causative agent of dental caries, is considered to be the most cariogenic among all oral streptococci. Of the four S. mutans serotypes (c, e, f, and k), serotype c strains predominate in the oral cavity. Here, we present the complete genome sequence of S. mutans GS-5, a serotype c strain originally isolated from human carious lesions, which is extensively used as a laboratory strain worldwide.

A Novel Botulinum Neurotoxin, Previously Reported as Serotype H, Has a Hybrid-Like Structure With Regions of Similarity to the Structures of Serotypes A and F and Is Neutralized With Serotype A Antitoxin

PubMed Central

Maslanka, Susan E.; Lúquez, Carolina; Dykes, Janet K.; Tepp, William H.; Pier, Christina L.; Pellett, Sabine; Raphael, Brian H.; Kalb, Suzanne R.; Barr, John R.; Rao, Agam; Johnson, Eric A.

2016-01-01

Botulism is a potentially fatal paralytic disease caused by the action of botulinum neurotoxin (BoNT) on nerve cells. There are 7 known serotypes (A–G) of BoNT and up to 40 genetic variants. Clostridium botulinum strain IBCA10-7060 was recently reported to produce BoNT serotype B (BoNT/B) and a novel BoNT, designated as BoNT/H. The BoNT gene (bont) sequence of BoNT/H was compared to known bont sequences. Genetic analysis suggested that BoNT/H has a hybrid-like structure containing regions of similarity to the structures of BoNT/A1 and BoNT/F5. This novel BoNT was serologically characterized by the mouse neutralization assay and a neuronal cell–based assay. The toxic effects of this hybrid-like BoNT were completely eliminated by existing serotype A antitoxins, including those contained in multivalent therapeutic antitoxin products that are the mainstay of human botulism treatment. PMID:26068781

Draft Genome Sequences of Clinical Isolates of Serotype 6E Streptococcus pneumoniae from Five Asian Countries.

PubMed

Park, In Ho; Baek, Jin Yang; Song, Jae-Hoon; Ko, Kwan Soo; Kim, Kyung-Hyo

2017-03-09

Although serotype 6E Streptococcus pneumoniae consistently expresses capsules of either vaccine-serotype 6A or 6B, certain genetic variants of serotype 6E may evade vaccine induced immunity. Thus, draft genome sequences from five clinical isolates of serotype 6E from each of five different Asian countries have been generated to provide insight into the genomic diversity in serotype 6E strains. Copyright © 2017 Park et al.

Effect of Serotype on Pneumococcal Competition in a Mouse Colonization Model.

PubMed

Trzciński, Krzysztof; Li, Yuan; Weinberger, Daniel M; Thompson, Claudette M; Cordy, Derrick; Bessolo, Andrew; Malley, Richard; Lipsitch, Marc

2015-09-15

Competitive interactions between Streptococcus pneumoniae strains during host colonization could influence the serotype distribution in nasopharyngeal carriage and pneumococcal disease. We evaluated the competitive fitness of strains of serotypes 6B, 14, 19A, 19F, 23F, and 35B in a mouse model of multiserotype carriage. Isogenic variants were constructed using clinical strains as the capsule gene donors. Animals were intranasally inoculated with a mixture of up to six pneumococcal strains of different serotypes, with separate experiments involving either clinical isolates or isogenic capsule-switch variants of clinical strain TIGR4. Upper-respiratory-tract samples were repeatedly collected from animals in order to monitor changes in the serotype ratios using quantitative PCR. A reproducible hierarchy of capsular types developed in the airways of mice inoculated with multiple strains. Serotype ranks in this hierarchy were similar among pneumococcal strains of different genetic backgrounds in different strains of mice and were not altered when tested under a range of host conditions. This rank correlated with the measure of the metabolic cost of capsule synthesis and in vitro measure of pneumococcal cell surface charge, both parameters considered to be predictors of serotype-specific fitness in carriage. This study demonstrates the presence of a robust competitive hierarchy of pneumococcal serotypes in vivo that is driven mainly, but not exclusively, by the capsule itself. Streptococcus pneumoniae (pneumococcus) is the leading cause of death due to respiratory bacterial infections but also a commensal frequently carried in upper airways. Available vaccines induce immune responses against polysaccharides coating pneumococcal cells, but with over 90 different capsular types (serotypes) identified, they can only target strains of the selected few serotypes most prevalent in disease. Vaccines not only protect vaccinated individuals against disease but also protect by

Inactivation of avirulent Yersinia pestis in beef bologna by gamma irradiation

USDA-ARS?s Scientific Manuscript database

Yersinia pestis, a psychrotrophic pathogen capable of growth at refrigeration temperatures, can cause pharyngeal and gastrointestinal plague in humans as a result of eating contaminated foods. Because Y. pestis is listed as a select agent for food safety and defense, evaluation of food safety interv...

Epigenetic regulation of serotype expression antagonizes transcriptome dynamics in Paramecium tetraurelia.

PubMed

Cheaib, Miriam; Dehghani Amirabad, Azim; Nordström, Karl J V; Schulz, Marcel H; Simon, Martin

2015-08-01

Phenotypic variation of a single genotype is achieved by alterations in gene expression patterns. Regulation of such alterations depends on their time scale, where short-time adaptations differ from permanently established gene expression patterns maintained by epigenetic mechanisms. In the ciliate Paramecium, serotypes were described for an epigenetically controlled gene expression pattern of an individual multigene family. Paradoxically, individual serotypes can be triggered in Paramecium by alternating environments but are then stabilized by epigenetic mechanisms, thus raising the question to which extend their expression follows environmental stimuli. To characterize environmental adaptation in the context of epigenetically controlled serotype expression, we used RNA-seq to characterize transcriptomes of serotype pure cultures. The resulting vegetative transcriptome resource is first analysed for genes involved in the adaptive response to the altered environment. Secondly, we identified groups of genes that do not follow the adaptive response but show co-regulation with the epigenetically controlled serotype system, suggesting that their gene expression pattern becomes manifested by similar mechanisms. In our experimental set-up, serotype expression and the entire group of co-regulated genes were stable among environmental changes and only heat-shock genes altered expression of these gene groups. The data suggest that the maintenance of these gene expression patterns in a lineage represents epigenetically controlled robustness counteracting short-time adaptation processes. © The Author 2015. Published by Oxford University Press on behalf of Kazusa DNA Research Institute.

Dengue serotype-specific immune response in Aedes aegypti and Aedes albopictus

PubMed Central

Smartt, Chelsea T; Shin, Dongyoung; Alto, Barry W

2017-01-01

BACKGROUND Dengue viruses (DENV) are considered one of the most important emerging pathogens and dengue disease is a global health threat. The geographic expansion of dengue viruses has led to co-circulation of all four dengue serotypes making it imperative that new DENV control strategies be devised. OBJECTIVES Here we characterize dengue serotype-specific innate immune responses in Aedes aegypti and Aedes albopictus using DENV from Puerto Rico (PR). METHODS Ae. aegypti and Ae. albopictus were infected with dengue serotype 1 and 2 isolated from Puerto Rico. DENV infected mosquito samples were collected and temporal change in expression of selected innate immune response pathway genes analyzed by quantitative real time PCR. FINDINGS The Toll pathway is involved in anti-dengue response in Ae. aegypti, and Ae. albopictus. Infections with PR DENV- 1 elicited a stronger response from genes of the Toll immune pathway than PR DENV-2 in Ae. aegypti but in infected Ae. albopictus expression of Toll pathway genes tended to be similar between the serotypes. Two genes (a ribosomal S5 protein gene and a nimrod-like gene) from Ae. albopictus were expressed in response to DENV. MAIN CONCLUSIONS These studies revealed a role for antiviral genes in DENV serotype-specific interactions with DENV vectors, demonstrated that infections with DENV-2 can modulate the Toll immune response pathway in Ae. aegypti and elucidated candidate molecules that might be used to interfere with serotype specific vector-virus interactions. PMID:29211244

Dengue serotype-specific immune response in Aedes aegypti and Aedes albopictus.

PubMed

Smartt, Chelsea T; Shin, Dongyoung; Alto, Barry W

2017-12-01

Dengue viruses (DENV) are considered one of the most important emerging pathogens and dengue disease is a global health threat. The geographic expansion of dengue viruses has led to co-circulation of all four dengue serotypes making it imperative that new DENV control strategies be devised. Here we characterize dengue serotype-specific innate immune responses in Aedes aegypti and Aedes albopictus using DENV from Puerto Rico (PR). Ae. aegypti and Ae. albopictus were infected with dengue serotype 1 and 2 isolated from Puerto Rico. DENV infected mosquito samples were collected and temporal change in expression of selected innate immune response pathway genes analyzed by quantitative real time PCR. The Toll pathway is involved in anti-dengue response in Ae. aegypti, and Ae. albopictus. Infections with PR DENV- 1 elicited a stronger response from genes of the Toll immune pathway than PR DENV-2 in Ae. aegypti but in infected Ae. albopictus expression of Toll pathway genes tended to be similar between the serotypes. Two genes (a ribosomal S5 protein gene and a nimrod-like gene) from Ae. albopictus were expressed in response to DENV. These studies revealed a role for antiviral genes in DENV serotype-specific interactions with DENV vectors, demonstrated that infections with DENV-2 can modulate the Toll immune response pathway in Ae. aegypti and elucidated candidate molecules that might be used to interfere with serotype specific vector-virus interactions.

Trends of invasive pneumococcal disease and its serotypes in the Autonomous Community of Madrid.

PubMed

Latasa Zamalloa, Pello; Sanz Moreno, Juan Carlos; Ordobás Gavín, María; Barranco Ordoñez, María Dolores; Insúa Marisquerena, Esther; Gil de Miguel, Ángel; Fernández Chávez, Abelardo Claudio; García-Comas, Luis

2017-12-05

Streptococcus pneumoniae is an important cause of morbidity. Vaccination is the most effective measure to prevent it. The aim of this study is to analyse the evolution of invasive pneumococcal disease (IPD). Observational study of IPD cases notified to the Epidemiological Surveillance Network of the Autonomous Community of Madrid between 2008 and 2015. The IPD case was defined as the disease caused by Streptococcus pneumoniae, with isolation and DNA or antigen detection, in samples from normally sterile sites. The isolated strains were sent to the Regional Public Health Laboratory for identification of the serotype. Serotypes were classified according to their inclusion in the 7-valent conjugate vaccine (PCV7), in the 13-valent vaccine, but not in the 7-valent vaccine (PCV13-additional) and not included in the 13-valent vaccine (non-PCV). The Incidence Rate Ratios (IRRs) were calculated comparing the 2011-2012 and 2013-2015 periods with the 2008-2010 period. 4,307 cases were reported. 86.6% were serotyped. The IRR of IPD was 0.67 and 0.67 for all serotypes; 0.43 and 0.45 for PCV7 serotypes; 0.46 and 0.25 for PCV13-additional serotypes, and 1.01 and 1.32 for non-PCV13 serotypes in the 2011-2012 and 2013-2015 periods. The incidence of serotypes 8, 9N, 10A, 23B, 24F and serogroup 33 increased significantly in the 2013-2015 period. Serotypes 15B and 24F accounted for 24% of non-PCV13 cases in children under 5years, serotypes 8 and 9N for 51% in the population aged 5 to 59years and serotypes 8 and 22F for 25% in the population aged over 59years. The incidence of serotypes not included in conjugate vaccines has increased, especially in children under 5years, but the total incidence of IPD has decreased. It is important to continue with the epidemiological and microbiological surveillance programmes to assess the effect of vaccination on the incidence of IPD. Copyright © 2017 Elsevier España, S.L.U. and Sociedad Española de Enfermedades Infecciosas y Microbiología Cl

[Homology analysis of the extended-V region of the surface proteins in different serotype Streptococcus mutans].

PubMed

He, Kui-Fang; Liu, Jian-Guo; Liu, Tian-Jia; Yang, De-Qin; Zhuang, Heng; Li, Song

2006-08-01

To analysis the homology among the extended-V region of the surface proteins in different serotype Streptococcus mutans (c, f, d, g) and to find out it's significance in anti-caries vaccine. The DNA of the bacteria (standarded serotype c, d, f, g and partial serotype c clinicals) was extracted and the extended-V region (SrV+, 1 384-2 514 bp) was amplified using polymerase chain reaction (PCR). Then the products were assessed using restriction fragment length polymorphism (RFLP) by endonuclease Dde I. The genotypings were sequenced and analysised using the program of BLAST on NCBI Gene Bank database. About 1.13 kb fragments were produced both in serotype c and f, the serotype d and g were failed. The RFLP results showed that five different patterns(A, B, C, D, E) among the 117 PCR products were reveled by Dde I. The ration of the genotypings A and B were the most among the strains, the C was lower, the D and E respectively was 1 and 3 strains per genotype. OMZ175 (serotype f) was belong to B genotype. Selected one of the A, B, C genotypings to sequenced and blasted. Then the results of the blastn showed that the identities of the gene sequence were 92%-98% between the serotype c and serotype f, part sequence of the serotype g was homology with the SrV+ of the serotype c, the protein sequence among serotype c, d, f, g were 77%-82%. It is reasonable to use some putative pipetides to study the anti-caries vaccine among the extended-V regions of the surface proteins in different serotype (c, d, f, g) in S. mutans.

Bactericidal Effect of Solar Water Disinfection under Real Sunlight Conditions▿

PubMed Central

Boyle, M.; Sichel, C.; Fernández-Ibáñez, P.; Arias-Quiroz, G. B.; Iriarte-Puña, M.; Mercado, A.; Ubomba-Jaswa, E.; McGuigan, K. G.

2008-01-01

Batch solar disinfection (SODIS) inactivation kinetics are reported for suspensions in water of Campylobacter jejuni, Yersinia enterocolitica, enteropathogenic Escherichia coli, Staphylococcus epidermidis, and endospores of Bacillus subtilis, exposed to strong natural sunlight in Spain and Bolivia. The exposure time required for complete inactivation (at least 4-log-unit reduction and below the limit of detection, 17 CFU/ml) under conditions of strong natural sunlight (maximum global irradiance, ∼1,050 W m−2 ± 10 W m−2) was as follows: C. jejuni, 20 min; S. epidermidis, 45 min; enteropathogenic E. coli, 90 min; Y. enterocolitica, 150 min. Following incomplete inactivation of B. subtilis endospores after the first day, reexposure of these samples on the following day found that 4% (standard error, 3%) of the endospores remained viable after a cumulative exposure time of 16 h of strong natural sunlight. SODIS is shown to be effective against the vegetative cells of a number of emerging waterborne pathogens; however, bacterial species which are spore forming may survive this intervention process. PMID:18359829

Omics strategies for revealing Yersinia pestis virulence

PubMed Central

Yang, Ruifu; Du, Zongmin; Han, Yanping; Zhou, Lei; Song, Yajun; Zhou, Dongsheng; Cui, Yujun

2012-01-01

Omics has remarkably changed the way we investigate and understand life. Omics differs from traditional hypothesis-driven research because it is a discovery-driven approach. Mass datasets produced from omics-based studies require experts from different fields to reveal the salient features behind these data. In this review, we summarize omics-driven studies to reveal the virulence features of Yersinia pestis through genomics, trascriptomics, proteomics, interactomics, etc. These studies serve as foundations for further hypothesis-driven research and help us gain insight into Y. pestis pathogenesis. PMID:23248778

Conformational changes in intact dengue virus reveal serotype-specific expansion

PubMed Central

Lim, Xin-Xiang; Chandramohan, Arun; Lim, Xin Ying Elisa; Bag, Nirmalya; Sharma, Kamal Kant; Wirawan, Melissa; Wohland, Thorsten; Lok, Shee-Mei; Anand, Ganesh S.

2017-01-01

Dengue virus serotype 2 (DENV2) alone undergoes structural expansion at 37 °C (associated with host entry), despite high sequence and structural homology among the four known serotypes. The basis for this differential expansion across strains and serotypes is unknown and necessitates mapping of the dynamics of dengue whole viral particles to describe their coordinated motions and conformational changes when exposed to host-like environments. Here we capture the dynamics of intact viral particles of two serotypes, DENV1 and DENV2, by amide hydrogen/deuterium exchange mass spectrometry (HDXMS) and time resolved Förster Resonance Energy Transfer. Our results show temperature-dependent dynamics hotspots on DENV2 and DENV1 particles with DENV1 showing expansion at 40 °C but not at 37 °C. HDXMS measurement of virion dynamics in solution offers a powerful approach to identify potential epitopes, map virus-antibody complex structure and dynamics, and test effects of multiple host-specific perturbations on viruses and virus-antibody complexes. PMID:28186093

[A new zoonosis--investigation of Gardnerella vaginalis disease of fox. V. Studies serotype of Gardnerella vaginalis in fox].

PubMed

Yan, X; Yan, Z; Yan, X; Luan, F; Wang, C

1996-10-01

145 strains Gardnerella vaginalis isolated in foxes were isolated from 13 main farms raising foxes in six provinces (regions), China, after antigenicity and immunogenicity of the strains were measured, 1-3 appropriate strains were selected from each farm raising foxes for serotype studies. Cross agglutinin absorption test confirmed that selected 26 strains Gardnerella vaginalis were divided into three serotypes and then the representing strains were used to produce typing serum. Among remaining 119 strain, 108 strains were typable with the typing sera, and 11 strains can't be set. Among three serotypes, serotype I made up 79.1% of the strains. It was shown that serotype I was the principal serotype of Gardnerella vaginalis of fox in China. The test also confirmed that 5 strains of Gardnerella vaginalis isolated from racoon dog, 4 strain Gardnerella vaginalis from mink and 2 strains Gardnerella vaginalis from canine also belonged to serotype I. Supersonic antigben was produced with three serotypes, representative strains. By agar immuno-diffusion test, it confirmed that the antigens of three serotypes formed a obvious blending precipitating line with the homologous or heterologous serotype antiserum. It indicated common antigen existed among all serotypes. The agar immuno-diffusion test results revealed that the precipitating line of the homologous serotype completely blended. It is our opinion that the method of serotyping is reliable.

Pediatric Invasive Pneumococcal Disease in Guatemala City: Importance of Serotype 2.

PubMed

Gaensbauer, James T; Asturias, Edwin J; Soto, Monica; Holt, Elizabeth; Olson, Daniel; Halsey, Neal A

2016-05-01

To inform estimations of the potential impact of recently introduced pneumococcal conjugate vaccine (PCV), we report results of 11 years of pre-PCV surveillance for invasive pneumococcal disease (IPD) among children in Guatemala City. Cases of IPD in children younger than 5 years were identified by active surveillance at 3 referral hospitals in Guatemala City from October 1996 through 2007. Clinical and demographic data were obtained, and isolates of Streptococcus pneumoniae from normally sterile sites were serotyped using latex agglutination and confirmed by Quellung reaction. Four hundred fifty-two cases of IPD were identified with a case fatality rate of 21%. Meningitis was the most common cause of death (77% of all deaths) and occurred more often in infancy (median age 5 months) than other clinical syndromes. Of the 137 isolates serotyped, type 1 (26 cases, 17%), type 2 (25 cases, 16%) and type 5 (18 cases, 12%) were the most common. Serotype 2 was associated with a higher case fatality rate (28%), higher rate of meningitis (68%) and occurred in younger infants (median age, 3.5 months) than other common serotypes. Recently introduced PCV13 includes 73% of observed serotypes in the study. Infants with IPD presented at a young age. Serotype 2, rarely reported as a significant cause of IPD and not included in available PCVs, was a common cause of disease in this population. PCV13 introduction in Guatemala, begun in 2013, may not have as great an impact in disease reduction as has been observed in other countries.

Longitudinal survey of the distribution of various serotypes of Streptococcus mutans in infants.

PubMed

Masuda, N; Tsutsumi, N; Sobue, S; Hamada, S

1979-10-01

The establishment of various serotypes of Streptococcus mutans was studied serologically in plaque samples collected from label surfaces of upper primary incisors of 22 infants (starting age, 5 to 13 months) over a period fo 30 months. Clinical examinations were also performed. No clear-cut association between the initiation of dental caries and previous detection of S. mutans was noted. However, all 12 of the infants with caries had S. mutans isolated at some time during the course of this study. The most common serotype isolated at the initial establishment of S. mutans on the tooth surfaces was serotype c, whereas types d, e, and g became established in a few cases. During the test period, changes in the distribution of serotypes of S. mutans were observed in some cases. The initiation of carious lesions could be found in a few cases even when S. mutans comprised about 1% or less of the total streptococcal count of the specimen from the tooth surfaces. Serotype d/g strains tended to develop carious lesions on smooth surfaces, although serotype c was isolated from almost all individuals who developed caries.

Completed Genome Sequences of Strains from 36 Serotypes of Salmonella

PubMed Central

Robertson, James; Yoshida, Catherine; Gurnik, Simone; Rankin, Marisa

2018-01-01

ABSTRACT We report here the completed closed genome sequences of strains representing 36 serotypes of Salmonella. These genome sequences will provide useful references for understanding the genetic variation between serotypes, particularly as references for mapping of raw reads or to create assemblies of higher quality, as well as to aid in studies of comparative genomics of Salmonella. PMID:29348347

Comparative efficacies of candidate antibiotics against Yersinia pestis in an in vitro pharmacodynamic model.

PubMed

Louie, Arnold; Vanscoy, Brian; Liu, Weiguo; Kulawy, Robert; Brown, David; Heine, Henry S; Drusano, George L

2011-06-01

Yersinia pestis, the bacterium that causes plague, is a potential agent of bioterrorism. Streptomycin is the "gold standard" for the treatment of plague infections in humans, but the drug is not available in many countries, and resistance to this antibiotic occurs naturally and has been generated in the laboratory. Other antibiotics have been shown to be active against Y. pestis in vitro and in vivo. However, the relative efficacies of clinically prescribed regimens of these antibiotics with streptomycin and with each other for the killing of Yersinia pestis are unknown. The efficacies of simulated pharmacokinetic profiles for human 10-day clinical regimens of ampicillin, meropenem, moxifloxacin, ciprofloxacin, and gentamicin were compared with the gold standard, streptomycin, for killing of Yersinia pestis in an in vitro pharmacodynamic model. Resistance amplification with therapy was also assessed. Streptomycin killed the microbe in one trial but failed due to resistance amplification in the second trial. In two trials, the other antibiotics consistently reduced the bacterial densities within the pharmacodynamic systems from 10⁸ CFU/ml to undetectable levels (<10² CFU/ml) between 1 and 3 days of treatment. None of the comparator agents selected for resistance. The comparator antibiotics were superior to streptomycin against Y. pestis and deserve further evaluation.

Outbreak-associated Salmonella enterica Serotypes and Food Commodities, United States, 1998–2008

PubMed Central

Griffin, Patricia M.; Cole, Dana; Walsh, Kelly A.; Chai, Shua J.

2013-01-01

Salmonella enterica infections are transmitted not only by animal-derived foods but also by vegetables, fruits, and other plant products. To clarify links between Salmonella serotypes and specific foods, we examined the diversity and predominance of food commodities implicated in outbreaks of salmonellosis during 1998–2008. More than 80% of outbreaks caused by serotypes Enteritidis, Heidelberg, and Hadar were attributed to eggs or poultry, whereas >50% of outbreaks caused by serotypes Javiana, Litchfield, Mbandaka, Muenchen, Poona, and Senftenberg were attributed to plant commodities. Serotypes Typhimurium and Newport were associated with a wide variety of food commodities. Knowledge about these associations can help guide outbreak investigations and control measures. PMID:23876503

Redistribution of Streptococcus pneumoniae Serotypes After Nationwide 13-valent Pneumococcal Conjugate Vaccine Program in Children in Northern Taiwan.

PubMed

Cho, Ying-Chun; Chiu, Nan-Chang; Lu, Chun-Yi; Huang, Daniel Tsung-Ning; Huang, Fu-Yuan; Chang, Luan-Yin; Huang, Li-Min; Chi, Hsin

2017-12-01

After the introduction of 13-valent pneumococcal conjugate vaccine (PCV13) against Streptococcus pneumoniae, public health officials in Taiwan monitored a decline in circulating vaccine serotypes and the emergence of nonvaccine serotypes in children with invasive pneumococcal disease. A gradually expanded PCV13 national immunization program was launched in 2013 in Taiwan. Here, we evaluate the changes in the distribution of pneumococcal serotypes and antimicrobial nonsusceptibility in children during the evolution of vaccination policy. S. pneumoniae isolates from children with pneumococcal disease were collected and serotyped from 2010 to 2015 in northern Taiwan. PCVs were administered at the recipients' expense between 2010 and 2012, and then PCV13 was partially reimbursed by the government beginning in 2013. The distribution and diversity of serotypes were analyzed along with their antimicrobial susceptibilities. Among a total of 498 isolates, the proportion of invasive pneumococcal disease isolates declined (47.1%-10.6%) during the study period, and serotype diversity increased after 2011. Between 2010 and 2012, the dominant serotypes were 19A, 19F, 3, 6B and 14, and serotype 19A rose from 44.1% to 57.5%. Serotypes 19A, 15A, 19F and 15B were more prevalent from 2013 to 2015, and serotype 19A decreased from 42.1% to 4.5%. Serotypes 19F and 15A became the most commonly detected serotypes in 2015. Overall, PCV13 additional serotypes were reduced by 80% (P < 0.0001) but nonvaccine serotypes increased from 8.8% to 51.5% (P < 0.0001). The step-by-step PCV13 national immunization program is effective against pneumococcal disease in Taiwanese children, mainly by reducing PCV13 additional serotypes.

El Niño-Southern Oscillation, local weather and occurrences of dengue virus serotypes

NASA Astrophysics Data System (ADS)

Huang, Xiaodong; Clements, Archie C. A.; Williams, Gail; Devine, Gregor; Tong, Shilu; Hu, Wenbiao

2015-11-01

Severe dengue fever is usually associated with secondary infection by a dengue virus (DENV) serotype (1 to 4) that is different to the serotype of the primary infection. Dengue outbreaks only occur following importations of DENV in Cairns, Australia. However, the majority of imported cases do not result in autochthonous transmission in Cairns. Although DENV transmission is strongly associated with the El Niño-Southern Oscillation (ENSO) climate cycle and local weather conditions, the frequency and potential risk factors of infections with the different DENV serotypes, including whether or not they differ, is unknown. This study used a classification tree model to identify the hierarchical interactions between Southern Oscillation Index (SOI), local weather factors, the presence of imported serotypes and the occurrence of the four autochthonous DENV serotypes from January 2000-December 2009 in Cairns. We found that the 12-week moving average of SOI and the 2-week moving average of maximum temperature were the most important factors influencing the variation in the weekly occurrence of the four DENV serotypes, the likelihoods of the occurrence of the four DENV serotypes may be unequal under the same environmental conditions, and occurrence may be influenced by changes in global and local environmental conditions in Cairns.

Biofilm-Forming Abilities of Listeria monocytogenes Serotypes Isolated from Different Sources

PubMed Central

Doijad, Swapnil P.; Barbuddhe, Sukhadeo B.; Garg, Sandeep; Poharkar, Krupali V.; Kalorey, Dewanand R.; Kurkure, Nitin V.; Rawool, Deepak B.; Chakraborty, Trinad

2015-01-01

A total of 98 previously characterized and serotyped L. monocytogenes strains, comprising 32 of 1/2a; 20 of 1/2b and 46 of 4b serotype, from clinical and food sources were studied for their capability to form a biofilm. The microtiter plate assay revealed 62 (63.26%) strains as weak, 27 (27.55%) strains as moderate, and 9 (9.18%) strains as strong biofilm formers. Among the strong biofilm formers, 6 strains were of serotype 1/2a and 3 strains were of serotype 1/2b. None of the strain from 4b serotype exhibited strong biofilm formation. No firm correlation (p = 0.015) was noticed between any serotype and respective biofilm formation ability. Electron microscopic studies showed that strong biofilm forming isolates could synthesize a biofilm within 24 h on surfaces important in food industries such as stainless steel, ceramic tiles, high-density polyethylene plastics, polyvinyl chloride pipes, and glass. Cell enumeration of strong, moderate, and weak biofilm was performed to determine if the number of cells correlated with the biofilm-forming capabilities of the isolates. Strong, moderate, and weak biofilm showed 570±127× 103 cells/cm2, 33±26× 103 cells/cm2, 5±3× 103 cells/cm2, respectively, indicating that the number of cells was directly proportional to the strength of the biofilm. The hydrophobicity index (HI) analysis revealed higher hydrophobicity with an increased biofilm formation. Fatty acid methyl esterase analysis revealed the amount of certain fatty acids such as iso-C15:0, anteiso-C15:0, and anteiso-C17:0 fatty acids correlated with the biofilm-forming capability of L. monocytogenes. This study showed that different strains of L. monocytogenes form biofilm of different intensities which did not completely correlate with their serotype; however, it correlated with the number of cells, hydrophobicity, and amount of certain fatty acids. PMID:26360831

Immunological properties of the primer-independent glucosyltransferase of Streptococcus mutans serotypes d and g.

PubMed

Yamashita, Y; Shigeoka, T; Hanada, N; Takehara, T

1988-05-01

Streptococcus mutans serotype g secretes at least three kinds of glucosyltransferase with different enzymological and immunological properties. One of them is a primer-independent enzyme and seems to be the source of primer for the others, both of which are primer-dependent enzymes. Recently, we purified the primer-independent enzyme, the third glucosyltransferase in this group from S. mutans strain AHT-k serotype g. In the present study, we examined the specificity of the antiserum against the primer-independent glucosyltransferase using extracellular culture-conditioned fluids of many strains of the various serotypes of S. mutans. The antiserum cross-reacted with the extracellular culture fluids from strains of serotypes d and a, in addition to serotype g, but not with those of other serotypes, indicating that the primer-independent glucosyltransferase is secreted by the S. sobrinus and S. cricetus, but not by S. mutans and S. rattus. The antiserum did not completely inhibit the activity of the enzyme, even at more than twofold antibody excess, determined by indirect precipitation with immobilized staphylococcal protein A.

Genome-scale reconstruction of the metabolic network in Yersinia pestis, strain 91001

DOE Office of Scientific and Technical Information (OSTI.GOV)

Navid, A; Almaas, E

2009-01-13

The gram-negative bacterium Yersinia pestis, the aetiological agent of bubonic plague, is one the deadliest pathogens known to man. Despite its historical reputation, plague is a modern disease which annually afflicts thousands of people. Public safety considerations greatly limit clinical experimentation on this organism and thus development of theoretical tools to analyze the capabilities of this pathogen is of utmost importance. Here, we report the first genome-scale metabolic model of Yersinia pestis biovar Mediaevalis based both on its recently annotated genome, and physiological and biochemical data from literature. Our model demonstrates excellent agreement with Y. pestis known metabolic needs andmore » capabilities. Since Y. pestis is a meiotrophic organism, we have developed CryptFind, a systematic approach to identify all candidate cryptic genes responsible for known and theoretical meiotrophic phenomena. In addition to uncovering every known cryptic gene for Y. pestis, our analysis of the rhamnose fermentation pathway suggests that betB is the responsible cryptic gene. Despite all of our medical advances, we still do not have a vaccine for bubonic plague. Recent discoveries of antibiotic resistant strains of Yersinia pestis coupled with the threat of plague being used as a bioterrorism weapon compel us to develop new tools for studying the physiology of this deadly pathogen. Using our theoretical model, we can study the cell's phenotypic behavior under different circumstances and identify metabolic weaknesses which may be harnessed for the development of therapeutics. Additionally, the automatic identification of cryptic genes expands the usage of genomic data for pharmaceutical purposes.« less

Genotyping of Global Yersinia Pestis Isolates by Using IS285

DTIC Science & Technology

2006-11-01

clones and to detect their geographical/ animal origin. 1. INTRODUCTION Yersinia pestis is the causative agent of plague circulating in natural...foci among about 200 species of rodents and lagomorphs. Humans usually become infected from animals via fleabites and display the bubonic form of...philogenetic relationships between Y. pestis strains, their potential geographical and animal origin. 2. GENOTYPING OF Y. PESTIS – CLUSTERING

Poliovirus serotype-specific VP1 sequencing primers.

PubMed

Kilpatrick, David R; Iber, Jane C; Chen, Qi; Ching, Karen; Yang, Su-Ju; De, Lina; Mandelbaum, Mark D; Emery, Brian; Campagnoli, Ray; Burns, Cara C; Kew, Olen

2011-06-01

The Global Polio Laboratory Network routinely uses poliovirus-specific PCR primers and probes to determine the serotype and genotype of poliovirus isolates obtained as part of global poliovirus surveillance. To provide detailed molecular epidemiologic information, poliovirus isolates are further characterized by sequencing the ~900-nucleotide region encoding the major capsid protein, VP1. It is difficult to obtain quality sequence information when clinical or environmental samples contain poliovirus mixtures. As an alternative to conventional methods for resolving poliovirus mixtures, sets of serotype-specific primers were developed for amplifying and sequencing the VP1 regions of individual components of mixed populations of vaccine-vaccine, vaccine-wild, and wild-wild polioviruses. Published by Elsevier B.V.

Isolation and serotyping of Streptococcus mutans from teeth and feces of children.

PubMed

Hamada, S; Masuda, N; Kotani, S

1980-04-01

Streptococcus mutans were detected in the feces from 10 of 29 caries-active patients, aged 4 to 9 years. The percentage of S. mutans to the total counts of facultatively anaerobic streptococci on mitis salivarius agar (Difco Laboratories) varied from 0 to 72.5%. S. mutans were then isolated from dental plaque of sound teeth and carious dentin of the 10 subjects known to harbor S. mutans in the feces. The frequency distribution of various serotypes of these dental and fecal isolates of S. mutans was compared by the immunodiffusion technique. Of the total 1,047 isolates (290 isolates from feces, 289 from dental plaque, and 468 from carious dentin), type c isolates were most prevalent (ca. 66%). Serotype d, e, f, and g isolates were also found but in far lower frequencies. Plural serotypes of S. mutans were occasionally found in dental and fecal samples of a single subject. For two subjects, relatively rare serotypes of S. mutans in the population examined, serotype e, f, or g, were predominantly found in their fecal and dental samples and those of their siblings and mother, suggesting an intrafamilial transmission of S. mutans.

Molecular detection assay of five Salmonella serotypes of public interest: Typhimurium, Enteritidis, Newport, Heidelberg, and Hadar.

PubMed

Bugarel, M; Tudor, A; Loneragan, G H; Nightingale, K K

2017-03-01

Foodborne illnesses due to Salmonella represent an important public-health concern worldwide. In the United States, a majority of Salmonella infections are associated with a small number of serotypes. Furthermore, some serotypes that are overrepresented among human disease are also associated with multi-drug resistance phenotypes. Rapid detection of serotypes of public-health concern might help reduce the burden of salmonellosis cases and limit exposure to multi-drug resistant Salmonella. We developed a two-step real-time PCR-based rapid method for the identification and detection of five Salmonella serotypes that are either overrepresented in human disease or frequently associated with multi-drug resistance, including serotypes Enteritidis, Typhimurium, Newport, Hadar, and Heidelberg. Two sets of four markers were developed to detect and differentiate the five serotypes. The first set of markers was developed as a screening step to detect the five serotypes; whereas, the second set was used to further distinguish serotypes Heidelberg, Newport and Hadar. The utilization of these markers on a two-step investigation strategy provides a diagnostic specificity of 97% for the detection of Typhimurium, Enteritidis, Heidelberg, Infantis, Newport and Hadar. The diagnostic sensitivity of the detection makers is >96%. The availability of this two-step rapid method will facilitate specific detection of Salmonella serotypes that contribute to a significant proportion of human disease and carry antimicrobial resistance. Published by Elsevier B.V.

Genome assemblies for 11 Yersinia pestis strains isolated in the Caucasus region

DOE PAGES

Zhgenti, Ekaterine; Johnson, Shannon L.; Davenport, Karen W.; ...

2015-09-17

Yersinia pestis, the causative agent of plague, is endemic to the Caucasus region but few reference strain genome sequences from that region are available. We present the improved draft or finished assembled genomes from 11 strains isolated in the nation of Georgia and surrounding countries.

In Vitro Antibacterial Activity of Several Plant Extracts and Oils against Some Gram-Negative Bacteria

PubMed Central

Al-Mariri, Ayman; Safi, Mazen

2014-01-01

Background: Medicinal plants are considered new resources for producing agents that could act as alternatives to antibiotics in the treatment of antibiotic-resistant bacteria. The aim of this study was to evaluate the antibacterial activity of 28 plant extracts and oils against four Gram-negative bacterial species. Methods: Experimental, in vitro, evaluation of the activities of 28 plant extracts and oils as well as some antibiotics against E. coli O157:H7, Yersinia enterocolitica O9, Proteus spp., and Klebsiella pneumoniae was performed. The activity against 15 isolates of each bacterium was determined by disc diffusion method at a concentration of 5%. Microdilution susceptibility assay was used in order to determine the minimal inhibitory concentrations (MICs) of the plant extracts, oils, and antibiotics. Results: Among the evaluated herbs, only Origanum syriacum L., Thymus syriacus Boiss., Syzygium aromaticum L., Juniperus foetidissima Wild, Allium sativum L., Myristica fragrans Houtt, and Cinnamomum zeylanicum L. essential oils and Laurus nobilis L. plant extract showed anti-bacterial activity. The MIC50 values of these products against the Gram-negative organisms varied from 1.5 (Proteus spp. and K. pneumoniae( and 6.25 µl/ml (Yersinia enterocolitica O9 ) to 12.5 µl/ml (E. coli O:157). Conclusion: Among the studied essential oils, O. syriacum L., T. syriacus Boiss., C. zeylanicum L., and S. aromaticum L. essential oils were the most effective. Moreover, Cephalosporin and Ciprofloxacin were the most effective antibiotics against almost all the studied bacteria. Therefore, O. syriacum L., T. syriacus Boiss., C. zeylanicum L., and S. aromaticum L. could act as bactericidal agents against Gram-negative bacteria. PMID:24453392

Other age groups than children need to be considered as carriers of Streptococcal pneumoniae serotypes.

PubMed

Slotved, Hans-Christian

2016-10-02

We need to raise the issue that focus on children as the only carriage group for pneumococci is not optimal; we need to consider that other age groups might also be carriers of pneumococcal serotypes causing invasive pneumococcal diseases (IPD) in unvaccinated age groups. The pneumococcal conjugate vaccines (PCV) have successfully removed IPD from vaccinated children. Studies have shown an effect of PCV reducing the pneumococcal carriage of PCV serotypes in children. The status for several countries having used PCV for many years is that they do not see PCV serotypes neither carried nor as a cause of IPD in children. PCV vaccination of children has shown a herd protection effect in unvaccinated groups as a reduction in IPD cases caused by PCV serotypes. However, not all PCV serotypes have disappeared as the cause of IPD in the unvaccinated age groups. The author therefore believes that if we are to see PCV serotypes disappear as a cause of IPD in unvaccinated age groups, we need to perform further carriage studies to examine carriage in other age groups. Alternatively, all age groups should be vaccinated against pneumococci to eliminate IPD caused by PCV serotypes from possible hidden carriers.

BK Polyomavirus Genotypes Represent Distinct Serotypes with Distinct Entry Tropism

PubMed Central

Pastrana, Diana V.; Ray, Upasana; Magaldi, Thomas G.; Schowalter, Rachel M.; Çuburu, Nicolas

2013-01-01

BK polyomavirus (BKV) causes significant urinary tract pathogenesis in immunosuppressed individuals, including kidney and bone marrow transplant recipients. It is currently unclear whether BKV-neutralizing antibodies can moderate or prevent BKV disease. We developed reporter pseudoviruses based on seven divergent BKV isolates and performed neutralization assays on sera from healthy human subjects. The results demonstrate that BKV genotypes I, II, III, and IV are fully distinct serotypes. While nearly all healthy subjects had BKV genotype I-neutralizing antibodies, a majority of subjects did not detectably neutralize genotype III or IV. Surprisingly, BKV subgenotypes Ib1 and Ib2 can behave as fully distinct serotypes. This difference is governed by as few as two residues adjacent to the cellular glycan receptor-binding site on the virion surface. Serological analysis of mice given virus-like particle (VLP)-based BKV vaccines confirmed these findings. Mice administered a multivalent VLP vaccine showed high-titer serum antibody responses that potently cross-neutralized all tested BKV genotypes. Interestingly, each of the neutralization serotypes bound a distinct spectrum of cell surface receptors, suggesting a possible connection between escape from recognition by neutralizing antibodies and cellular attachment mechanisms. The finding implies that different BKV genotypes have different cellular tropisms and pathogenic potentials in vivo. Individuals who are infected with one BKV serotype may remain humorally vulnerable to other BKV serotypes after implementation of T cell immunosuppression. Thus, prevaccinating organ transplant recipients with a multivalent BKV VLP vaccine might reduce the risk of developing posttransplant BKV disease. PMID:23843634

Production of a unique pneumococcal capsule serotype belonging to serogroup 6

PubMed Central

Bratcher, Preston E.; Park, In H.; Hollingshead, Susan K.; Nahm, Moon H.

2013-01-01

Serogroup 6 of Streptococcus pneumoniae contains three serotypes named 6A, 6B and 6C with highly homologous capsule gene loci. The 6A and 6B capsule gene loci consistently differ from each other by only one nucleotide in the wciP gene. The 6A capsule gene locus has a galactosyl transferase, which has been replaced with a glucosyl transferase in the 6C capsule gene locus. We considered that a new serotype named “6X1” would be possible if the galactosyl transferase of the 6B capsule gene locus is replaced with the glucosyl transferase of 6C. We demonstrate that this gene transfer yields a viable pneumococcal strain and the capsular polysaccharide from this strain has the predicted chemical structure and serologic similarity to the capsular polysaccharide of the 6B serotype. The new strain (i.e., serotype 6X1) is typed as 6B by the quellung reaction but it can be distinguished from 6B strains with monoclonal antibodies to 6B polysaccharide. Reexamination of 264 pneumococcal isolates that were previously typed as 6B with classical typing methods revealed no isolates expressing serotype 6X1. Nevertheless, this study shows this capsular polysaccharide is biochemically possible and could exist/emerge in nature. PMID:19202106

Yersinia pestis and host macrophages: immunodeficiency of mouse macrophages induced by YscW.

PubMed

Bi, Yujing; Du, Zongmin; Han, Yanping; Guo, Zhaobiao; Tan, Yafang; Zhu, Ziwen; Yang, Ruifu

2009-09-01

The virulence of the pathogenic Yersinia species depends on a plasmid-encoded type III secretion system (T3SS) that transfers six Yersinia outer protein (Yop) effector proteins into the cytoplasm of eukaryotic cells, leading to disruption of host defence mechanisms. It is shown in this study that Yersinia pestis YscW, a protein of the T3SS injectisome, contributes to the induction of a deficiency in phagocytosis in host macrophages and a reduction in their antigen-presenting capacity. A Y. pestis strain lacking yscW had no effect on uptake by host macrophages. In mice infected with wild-type Y. pestis, the yscW mutant or a complement strain, immunodeficiency was observed in host macrophages compared with those from uninfected mice. However, the phagocytosis and antigen presenting capacities of macrophages infected by yscW mutant strain both in vivo and in vitro were significantly higher than those by wild type strain. Consistent with this finding, when YscW was expressed in the RAW264.7 macrophage cell line, phagocytosis and antigen-presenting capacities were significantly lower than those of the control groups. These results indicate that Y. pestis YscW may directly induce immunodeficiency in murine macrophages by crippling their phagocytosis and antigen-presenting capacities. These data provide evidences to Y. pestis pathogenesis that some proteins in T3SS injectisome, such as YscW protein, might play independent roles in disrupting host defense apart from their known functions.

Complete Genome Sequence of Pigmentation Negative Yersinia Pestis strain Cadman Running head: Complete Genome Sequence of Y. pestis strain Cadman

DTIC Science & Technology

2016-10-27

Institute of Infectious Diseases, Fort Detrick, Frederick, Maryland, USA 9 10 11 Running head: Complete Genome Sequence of Y. pestis strain Cadman...1 Complete Genome Sequence of Pigmentation Negative Yersinia pestis strain Cadman 1 2 3 Sean Lovetta, Kitty Chaseb, Galina Korolevaa, Gustavo...we report the genome sequence of Yersinia pestis strain Cadman, an attenuated strain 25 lacking the pgm locus. Y. pestis is the causative agent of

Capsular serotypes, virulence-associated genes and antimicrobial susceptibility of Streptococcus suis isolates from pigs in Korea.

PubMed

Oh, Sang-Ik; Jeon, Albert Byungyun; Jung, Byeong-Yeal; Byun, Jae-Won; Gottschalk, Marcelo; Kim, Aeran; Kim, Jong Wan; Kim, Ha-Young

2017-04-20

Streptococcus suis is an important pig pathogen with potential for human transmission. The serotype distributions and phenotypic characteristics vary over time and among regions; however, little is known about the characteristics of S. suis isolates in Korea. In this study, 240 S. suis isolates collected from pigs in Korea in 2009-2010 were serotyped by coagglutination tests, subsequently screened for three virulence-associated genes (mrp, epf and sly) and tested for antimicrobial susceptibility. As for 80 isolates, the serotypes of which were relevant to human infections, clonal complexes (CCs) were further identified by PCR. Serotype 3 was the most prevalent (15.8%), followed by serotype 2 (15.0%), with geographical variation for each serotype. Overall, 55.4% of the isolates carried mrp, whereas only 3.8% carried epf. CC25 was the most prevalent (41.3%) and was related to serotypes 2 and 9. The isolates showed higher susceptibility to ampicillin (93.4%) and ceftiofur (90.8%) than to the other antimicrobial agents tested. The highest resistance rate was observed to tetracycline (98.0%), followed by erythromycin (88.8%). In addition, the resistance to certain antimicrobials was significantly associated, in part, with virulence-associated genes or serotypes. Therefore, continuous characterization of S. suis is essential for the benefit of veterinary and human medicine.

Streptococcus pneumoniae: distribution of serotypes and antimicrobial susceptibility in patients with cancer.

PubMed

Soto-Noguerón, Araceli; Carnalla-Barajas, María Noemí; Cornejo-Juárez, Patricia; Volkow-Fernández, Patricia; Velázquez-Meza, María Elena; Echániz-Aviles, Gabriela

2018-01-01

To describe the distribution of pneumococcal serotypes causing infectious diseases in patients with hematological malignancies and solid tumors and their antimicrobial susceptibility before and after introduction of pneumococcal conjugate vaccine (PCV7) in Mexico. Consecutive pneumococcal isolates from hospitalized patients from the SIREVA-network were serotyped using the Quellung reaction and antimicrobial susceptibility was performed using the broth microdilution method. A total of 175 pneumococcal isolates were recovered, 105 from patients with hematological malignancies and 70 with solid tumors. Serotypes 19A (22.7%), 19F (20.4%), and 35B (17.7%) were the most frequent isolates in the first group and serotypes 3 (27.2%) and 19A (28.6%) in the second group. No decreased susceptibility to beta-lactams or TMP/SMX was observed after introduction of PCV7. An increase in non-vaccine types is observed without significate changes in antimicrobial susceptibility after introduction of PCV7.

Historical overview of key issues in food safety.

PubMed Central

Foster, E. M.

1997-01-01

Foodborne transmission of pathogenic and toxigenic microorganisms has been a recognized hazard for decades. Even half a century ago we knew about the dangers of botulism from underprocessed canned foods; staphylococcal poisoning from unrefrigerated cream-filled pastries, sliced ham, meat, and poultry salads; and salmonellosis from infected animal products. Despite new protective measures, changes in preservation techniques and failure to follow recognized procedures have created new dangers. Moreover, we now recognize new organisms that can cause foodborne illness--Listeria monocytogenes, Escherichia coli O157:H7, Campylobacter jejuni, Vibrio parahaemolyticus, Yersinia enterocolitica, and others. Controlling these organisms will require widespread education and possibly new regulatory initiatives. PMID:9366600

Clonality and serotypes of Streptococcus mutans among children by multilocus sequence typing

PubMed Central

Momeni, Stephanie S.; Whiddon, Jennifer; Cheon, Kyounga; Moser, Stephen A.; Childers, Noel K.

2015-01-01

Studies using multilocus sequence typing (MLST) have demonstrated that Streptococcus mutans isolates are genetically diverse. Our laboratory previously demonstrated clonality of S. mutans using MLST but could not discount the possibility of sampling bias. In this study, the clonality of randomly selected S. mutans plaque isolates from African American children was examined using MLST. Serotype and presence of collagen-binding proteins (CBP) cnm/cbm were also assessed. One hundred S. mutans isolates were randomly selected for MLST analysis. Sequence analysis was performed and phylogenetic trees were generated using START2 and MEGA. Thirty-four sequence types (ST) were identified of which 27 were unique to this population. Seventy-five percent of the isolates clustered into 16 clonal groups. Serotypes observed were c (n=84), e (n=3), and k (n=11). The prevalence of S. mutans isolates serotype k was notably high at 17.5%. All isolates were cnm/cbm negative. The clonality of S. mutans demonstrated in this study illustrates the importance of localized populations studies and are consistent with transmission. The prevalence of serotype k, a recently proposed systemic pathogen, observed in this study is higher than reported in most populations and is the first report of S. mutans serotype k in a US population. PMID:26443288

An encapsulated Yersinia pseudotuberculosis is a highly efficient vaccine against pneumonic plague.

PubMed

Derbise, Anne; Cerdà Marín, Alba; Ave, Patrick; Blisnick, Thierry; Huerre, Michel; Carniel, Elisabeth; Demeure, Christian E

2012-01-01

Plague is still a public health problem in the world and is re-emerging, but no efficient vaccine is available. We previously reported that oral inoculation of a live attenuated Yersinia pseudotuberculosis, the recent ancestor of Yersinia pestis, provided protection against bubonic plague. However, the strain poorly protected against pneumonic plague, the most deadly and contagious form of the disease, and was not genetically defined. The sequenced Y. pseudotuberculosis IP32953 has been irreversibly attenuated by deletion of genes encoding three essential virulence factors. An encapsulated Y. pseudotuberculosis was generated by cloning the Y. pestis F1-encoding caf operon and expressing it in the attenuated strain. The new V674pF1 strain produced the F1 capsule in vitro and in vivo. Oral inoculation of V674pF1 allowed the colonization of the gut without lesions to Peyer's patches and the spleen. Vaccination induced both humoral and cellular components of immunity, at the systemic (IgG and Th1 cells) and the mucosal levels (IgA and Th17 cells). A single oral dose conferred 100% protection against a lethal pneumonic plague challenge (33×LD(50) of the fully virulent Y. pestis CO92 strain) and 94% against a high challenge dose (3,300×LD(50)). Both F1 and other Yersinia antigens were recognized and V674pF1 efficiently protected against a F1-negative Y. pestis. The encapsulated Y. pseudotuberculosis V674pF1 is an efficient live oral vaccine against pneumonic plague, and could be developed for mass vaccination in tropical endemic areas to control pneumonic plague transmission and mortality.

Adhesive Properties of YapV and Paralogous Autotransporter Proteins of Yersinia pestis

PubMed Central

Nair, Manoj K. M.; De Masi, Leon; Yue, Min; Galván, Estela M.; Chen, Huaiqing; Wang, Fang

2015-01-01

Yersinia pestis is the causative agent of plague. This bacterium evolved from an ancestral enteroinvasive Yersinia pseudotuberculosis strain by gene loss and acquisition of new genes, allowing it to use fleas as transmission vectors. Infection frequently leads to a rapidly lethal outcome in humans, a variety of rodents, and cats. This study focuses on the Y. pestis KIM yapV gene and its product, recognized as an autotransporter protein by its typical sequence, outer membrane localization, and amino-terminal surface exposure. Comparison of Yersinia genomes revealed that DNA encoding YapV or each of three individual paralogous proteins (YapK, YapJ, and YapX) was present as a gene or pseudogene in a strain-specific manner and only in Y. pestis and Y. pseudotuberculosis. YapV acted as an adhesin for alveolar epithelial cells and specific extracellular matrix (ECM) proteins, as shown with recombinant Escherichia coli, Y. pestis, or purified passenger domains. Like YapV, YapK and YapJ demonstrated adhesive properties, suggesting that their previously related in vivo activity is due to their capacity to modulate binding properties of Y. pestis in its hosts, in conjunction with other adhesins. A differential host-specific type of binding to ECM proteins by YapV, YapK, and YapJ suggested that these proteins participate in broadening the host range of Y. pestis. A phylogenic tree including 36 Y. pestis strains highlighted an association between the gene profile for the four paralogous proteins and the geographic location of the corresponding isolated strains, suggesting an evolutionary adaption of Y. pestis to specific local animal hosts or reservoirs. PMID:25690102

Serotype IV and invasive group B Streptococcus disease in neonates, Minnesota, USA, 2000-2010.

PubMed

Ferrieri, Patricia; Lynfield, Ruth; Creti, Roberta; Flores, Aurea E

2013-04-01

Group B Streptococcus (GBS) is a major cause of invasive disease in neonates in the United States. Surveillance of invasive GBS disease in Minnesota, USA, during 2000-2010 yielded 449 isolates from 449 infants; 257 had early-onset (EO) disease (by age 6 days) and 192 late-onset (LO) disease (180 at age 7-89 days, 12 at age 90-180 days). Isolates were characterized by capsular polysaccharide serotype and surface-protein profile; types III and Ia predominated. However, because previously uncommon serotype IV constitutes 5/31 EO isolates in 2010, twelve type IV isolates collected during 2000-2010 were studied further. By pulsed-field gel electrophoresis, they were classified into 3 profiles; by multilocus sequence typing, representative isolates included new sequence type 468. Resistance to clindamycin or erythromycin was detected in 4/5 serotype IV isolates. Emergence of serotype IV GBS in Minnesota highlights the need for serotype prevalence monitoring to detect trends that could affect prevention strategies.

Heatwaves differentially affect risk of Salmonella serotypes.

PubMed

Milazzo, Adriana; Giles, Lynne C; Zhang, Ying; Koehler, Ann P; Hiller, Janet E; Bi, Peng

2016-09-01

Given increasing frequency of heatwaves and growing public health concerns associated with foodborne disease, we examined the relationship between heatwaves and salmonellosis in Adelaide, Australia. Poisson regression analysis with Generalised Estimating Equations was used to estimate the effect of heatwaves and the impact of intensity, duration and timing on salmonellosis and specific serotypes notified from 1990 to 2012. Distributed lag non-linear models were applied to assess the non-linear and delayed effects of temperature during heatwaves on Salmonella cases. Salmonella typhimurium PT135 notifications were sensitive to the effects of heatwaves with a twofold (IRR 2.08, 95% CI 1.14-3.79) increase in cases relative to non-heatwave days. Heatwave intensity had a significant effect on daily counts of overall salmonellosis with a 34% increase in risk of infection (IRR 1.34, 95% CI 1.01-1.78) at >41 °C. The effects of temperature during heatwaves on Salmonella cases and serotypes were found at lags of up to 14 days. This study confirms heatwaves have a significant effect on Salmonella cases, and for the first time, identifies its impact on specific serotypes and phage types. These findings will contribute to the understanding of the impact of heatwaves on salmonellosis and provide insights that could mitigate their impact. Copyright © 2016 The British Infection Association. Published by Elsevier Ltd. All rights reserved.

Molecular diagnostics and ITS-based phylogenic analysis of Streptococcus suis serotype 2 in central Vietnam.

PubMed

Nguyen, Bach Hoang; Phan, Dieu Hong Nu; Nguyen, Hien Xuan; Le, An Van; Alberti, Alberto

2015-07-04

Streptococcus suis (S. suis) serotype 2 has recently become the most prevalent cause of meningitis in adults in many areas of Vietnam. This study provides data on S. suis molecular diagnosis in central Vietnam using a real-time polymerase chain reaction (PCR) assay targeting the S. suis serotype 2 cps2J gene. Additionally, 16S-23S rDNA intragenic spacer (ITS)-based phylogenic analysis of strains isolated from cerebrospinal fluid (CSF) in Thua Thien Hue Province, Vietnam, is presented and discussed. Pathogenic bacteria were isolated from 40 CSF samples, and 18 were identified as S. suis by culture-dependent methods. Capsular serotyping was assessed by real-time PCR. ITS sequences were obtained after traditional PCR and were used in phylogenic analyses. Pathogenic bacteria were isolated from 36 out of 40 CSF samples. A total of 18 S. suis strains were isolated and assigned to serotype 2 by real-time PCR. One CSF sample, negative when tested by culture-dependent methods, was positive to S. suis serotype 2 by real-time PCR. Pairwise alignments of the 18 ITS sequences did not reveal any variable nucleotide position, and resulted in a single sequence type. Sequences were similar to S. suis serotype 2 reference ITS sequences (> 98.1%), and there was no lack of an ITS spacer region in the isolates. S. suis serotype 2 is the most prevalent serotype in central Vietnam. Real-time PCR assay proved to be a reliable diagnostic method for early detection of S. suis 2 in CSF samples.

Capsular serotypes, virulence-associated genes and antimicrobial susceptibility of Streptococcus suis isolates from pigs in Korea

PubMed Central

OH, Sang-Ik; JEON, Albert Byungyun; JUNG, Byeong-Yeal; BYUN, Jae-Won; GOTTSCHALK, Marcelo; KIM, Aeran; KIM, Jong Wan; KIM, Ha-Young

2017-01-01

Streptococcus suis is an important pig pathogen with potential for human transmission. The serotype distributions and phenotypic characteristics vary over time and among regions; however, little is known about the characteristics of S. suis isolates in Korea. In this study, 240 S. suis isolates collected from pigs in Korea in 2009–2010 were serotyped by coagglutination tests, subsequently screened for three virulence-associated genes (mrp, epf and sly) and tested for antimicrobial susceptibility. As for 80 isolates, the serotypes of which were relevant to human infections, clonal complexes (CCs) were further identified by PCR. Serotype 3 was the most prevalent (15.8%), followed by serotype 2 (15.0%), with geographical variation for each serotype. Overall, 55.4% of the isolates carried mrp, whereas only 3.8% carried epf. CC25 was the most prevalent (41.3%) and was related to serotypes 2 and 9. The isolates showed higher susceptibility to ampicillin (93.4%) and ceftiofur (90.8%) than to the other antimicrobial agents tested. The highest resistance rate was observed to tetracycline (98.0%), followed by erythromycin (88.8%). In addition, the resistance to certain antimicrobials was significantly associated, in part, with virulence-associated genes or serotypes. Therefore, continuous characterization of S. suis is essential for the benefit of veterinary and human medicine. PMID:28250312

[Origin of the plague microbe Yersinia pestis: structure of the process of speciation].

PubMed

Suntsov, V V

2012-01-01

The origin and evolution of the plague microbe Yersinia pestis are considered in the context of propositions of modern Darwinism. It was shown that the plague pathogen diverged from the pseudotuberculous microbe Yersinia pseudotuberculosis O:1b in the mountain steppe landscapes of Central Asia in the Sartan: 22000-15000 years ago. Speciation occurred in the tarbagan (Marmota sibirica)--flea (Oropsylla silantiewi) parasitic system. The structure of the speciation process included six stages: isolation, genetic drift, enhancement of intrapopulational polymorphism, the beginning of pesticin synthesis (genetic conflict and emergence of hiatus), specialization (stabilization of characteristics), and adaptive irradiation (transformation of the monotypic species Y. pestis tarbagani into a polytypic species). The scenario opens up wide prospects for construction of the molecular phylogeny of the plague microbe Y. pestis and for investigation of the biochemical and molecular-genetic aspects of "Darwinian" evolution of pathogens from many other nature-focal infections.

Silencing urease: a key evolutionary step that facilitated the adaptation of Yersinia pestis to the flea-borne transmission route.

PubMed

Chouikha, Iman; Hinnebusch, B Joseph

2014-12-30

The arthropod-borne transmission route of Yersinia pestis, the bacterial agent of plague, is a recent evolutionary adaptation. Yersinia pseudotuberculosis, the closely related food-and water-borne enteric species from which Y. pestis diverged less than 6,400 y ago, exhibits significant oral toxicity to the flea vectors of plague, whereas Y. pestis does not. In this study, we identify the Yersinia urease enzyme as the responsible oral toxin. All Y. pestis strains, including those phylogenetically closest to the Y. pseudotuberculosis progenitor, contain a mutated ureD allele that eliminated urease activity. Restoration of a functional ureD was sufficient to make Y. pestis orally toxic to fleas. Conversely, deletion of the urease operon in Y. pseudotuberculosis rendered it nontoxic. Enzymatic activity was required for toxicity. Because urease-related mortality eliminates 30-40% of infective flea vectors, ureD mutation early in the evolution of Y. pestis was likely subject to strong positive selection because it significantly increased transmission potential.

Silencing urease: A key evolutionary step that facilitated the adaptation of Yersinia pestis to the flea-borne transmission route

PubMed Central

Chouikha, Iman; Hinnebusch, B. Joseph

2014-01-01

The arthropod-borne transmission route of Yersinia pestis, the bacterial agent of plague, is a recent evolutionary adaptation. Yersinia pseudotuberculosis, the closely related food-and water-borne enteric species from which Y. pestis diverged less than 6,400 y ago, exhibits significant oral toxicity to the flea vectors of plague, whereas Y. pestis does not. In this study, we identify the Yersinia urease enzyme as the responsible oral toxin. All Y. pestis strains, including those phylogenetically closest to the Y. pseudotuberculosis progenitor, contain a mutated ureD allele that eliminated urease activity. Restoration of a functional ureD was sufficient to make Y. pestis orally toxic to fleas. Conversely, deletion of the urease operon in Y. pseudotuberculosis rendered it nontoxic. Enzymatic activity was required for toxicity. Because urease-related mortality eliminates 30–40% of infective flea vectors, ureD mutation early in the evolution of Y. pestis was likely subject to strong positive selection because it significantly increased transmission potential. PMID:25453069

Complete nucleotide sequences of three pigeon paramyxovirus serotype-1 (PPMV-1) isolates

USDA-ARS?s Scientific Manuscript database

Pigeon paramyxovirus serotype-1 (PPMV-1) is an antigenic variant of avian paramyxovirus serotype-1 (APMV-1), the agent responsible for Newcastle disease. Given that PPMV-1 can be transmitted to the poultry population it is important to characterize PPMV-1 in native birds. Here we report the complet...

Genetic and pathogenic difference between Streptococcus agalactiae serotype Ia fish and human isolates.

PubMed

Chu, Chishih; Huang, Pei-Yu; Chen, Hung-Ming; Wang, Ying-Hsiang; Tsai, I-An; Lu, Chih-Cheng; Chen, Che-Chun

2016-08-02

Streptococcus agalactiae (GBS) is a common pathogen to infect newborn, woman, the elderly, and immuno-compromised human and fish. 37 fish isolates and 554 human isolates of the GBS in 2007-2012 were investigated in serotypes, antibiotic susceptibility, genetic difference and pathogenicity to tilapia. PCR serotyping determined serotype Ia for all fish GBS isolates and only in 3.2 % (3-4.2 %) human isolates. For fish isolates, all consisted a plasmid less than 6 kb and belonged to ST7 type, which includes mainly pulsotypes I and Ia, with a difference in a deletion at the largest DNA fragment. These fish isolates were susceptible to all antimicrobials tested in 2007 and increased in non-susceptibility to penicillin, and resistance to clindamycin and ceftriaxone in 2011. Differing in pulsotype and lacking plasmid from fish isolates, human serotype Ia isolates were separated into eight pulsotypes II-IX. Main clone ST23 included pulsotypes II and IIa (50 %) and ST483 consisted of pulsotype III. Human serotype Ia isolates were all susceptible to ceftriaxone and penicillin and few were resistant to erythromycin, azithromycin, clindamycin, levofloxacin and moxifloxacine with the resistant rate of 20 % or less. Using tilapia to analyze the pathogenesis, fish isolates could cause more severe symptoms, including hemorrhage of the pectoral fin, hemorrhage of the gill, and viscous black and common scites, and mortality (>95 % for pulsotype I) than the human isolates (<30 %); however, the fish pulostype Ia isolate 912 with deletion caused less symptoms and the lowest mortality (<50 %) than pulsotype I isolates. Genetic, pathogenic, and antimicrobial differences demonstrate diverse origin of human and fish serotype Ia isolates. The pulsotype Ia of fish serotype Ia isolates may be used as vaccine strains to prevent the GBS infection in fish.

Opsonophagocytic Antibodies to Serotype Ia, Ib, and III Group B Streptococcus among Korean Infants and in Intravenous Immunoglobulin Products.

PubMed

Kim, Han Wool; Lee, Ji Hyen; Cho, Hye Kyung; Lee, Hyunju; Seo, Ho Seong; Lee, Soyoung; Kim, Kyung Hyo

2017-05-01

Group B streptococcus (GBS) infection is a leading cause of sepsis and meningitis among infants, and is associated with high rates of morbidity and mortality in many countries. Protection against GBS typically involves antibody-mediated opsonization by phagocytes and complement components. The present study evaluated serotype-specific functional antibodies to GBS among Korean infants and in intravenous immunoglobulin (IVIG) products. An opsonophagocytic killing assay (OPA) was used to calculate the opsonization indices (OIs) of functional antibodies to serotypes Ia, Ib, and III in 19 IVIG products from 5 international manufacturers and among 98 Korean infants (age: 0-11 months). The GBS Ia, Ib, and III serotypes were selected because they are included in a trivalent GBS vaccine formulation that is being developed. The OI values for the IVIG products were 635-5,706 (serotype Ia), 488-1,421 (serotype Ib), and 962-3,315 (serotype III), and none of the IVIG lots exhibited undetectable OI values (< 4). The geometric mean OI values were similar for all 3 serotypes when we compared the Korean manufacturers. The seropositive rate among infants was significantly lower for serotype Ia (18.4%), compared to serotype Ib and serotype III (both, 38.8%). Infant age of ≥ 3 months was positively correlated with the seropositive rates for each serotype. Therefore, only a limited proportion of infants exhibited protective immunity against serotype Ia, Ib, and III GBS infections. IVIG products that exhibit high antibody titers may be a useful therapeutic or preventive measure for infants. Further studies are needed to evaluate additional serotypes and age groups. © 2017 The Korean Academy of Medical Sciences.

Opsonophagocytic Antibodies to Serotype Ia, Ib, and III Group B Streptococcus among Korean Infants and in Intravenous Immunoglobulin Products

PubMed Central

2017-01-01

Group B streptococcus (GBS) infection is a leading cause of sepsis and meningitis among infants, and is associated with high rates of morbidity and mortality in many countries. Protection against GBS typically involves antibody-mediated opsonization by phagocytes and complement components. The present study evaluated serotype-specific functional antibodies to GBS among Korean infants and in intravenous immunoglobulin (IVIG) products. An opsonophagocytic killing assay (OPA) was used to calculate the opsonization indices (OIs) of functional antibodies to serotypes Ia, Ib, and III in 19 IVIG products from 5 international manufacturers and among 98 Korean infants (age: 0–11 months). The GBS Ia, Ib, and III serotypes were selected because they are included in a trivalent GBS vaccine formulation that is being developed. The OI values for the IVIG products were 635–5,706 (serotype Ia), 488–1,421 (serotype Ib), and 962–3,315 (serotype III), and none of the IVIG lots exhibited undetectable OI values (< 4). The geometric mean OI values were similar for all 3 serotypes when we compared the Korean manufacturers. The seropositive rate among infants was significantly lower for serotype Ia (18.4%), compared to serotype Ib and serotype III (both, 38.8%). Infant age of ≥ 3 months was positively correlated with the seropositive rates for each serotype. Therefore, only a limited proportion of infants exhibited protective immunity against serotype Ia, Ib, and III GBS infections. IVIG products that exhibit high antibody titers may be a useful therapeutic or preventive measure for infants. Further studies are needed to evaluate additional serotypes and age groups. PMID:28378545

The role of the phoPQ operon in the pathogenesis of the fully virulent CO92 strain of Yersinia pestis and the IP32953 strain of Yersinia pseudotuberculosis.

PubMed

Bozue, Joel; Mou, Sherry; Moody, Krishna L; Cote, Christopher K; Trevino, Sylvia; Fritz, David; Worsham, Patricia

2011-06-01

At the genomic level, Yersinia pestis and Yersinia pseudotuberculosis are nearly identical but cause very different diseases. Y. pestis is the etiologic agent of plague; whereas Y. pseudotuberculosis causes a gastrointestinal infection primarily after the consumption of contaminated food. In many gram-negative pathogenic bacteria, PhoP is part of a two-component global regulatory system in which PhoQ serves as the sensor kinase, and PhoP is the response regulator. PhoP is known to activate a number of genes in many bacteria related to virulence. To determine the role of the PhoPQ proteins in Yersinia infections, primarily using aerosol challenge models, the phoP gene was deleted from the chromosome of the CO92 strain of Y. pestis and the IP32953 strain of Y. pseudotuberculosis, leading to a polar mutation of the phoPQ operon. We demonstrated that loss of phoPQ from both strains leads to a defect in intracellular growth and/or survival within macrophages. These in vitro data would suggest that the phoPQ mutants would be attenuated in vivo. However, the LD(50) for the Y. pestis mutant did not differ from the calculated LD(50) for the wild-type CO92 strain for either the bubonic or pneumonic murine models of infection. In contrast, mice challenged by aerosol with the Y. pseudotuberculosis mutant had a LD(50) value 40× higher than the wild-type strain. These results demonstrate that phoPQ are necessary for full virulence by aerosol infection with the IP32953 strain of Y. pseudotuberculosis. However, the PhoPQ proteins do not play a significant role in infection with a fully virulent strain of Y. pestis. Published by Elsevier India Pvt Ltd.

Shotgun proteomic analysis of Yersinia ruckeri isolates under normal and iron-limited conditions

USDA-ARS?s Scientific Manuscript database

Yersinia ruckeri is the causative agent of enteric redmouth disease of fish and causes significant economic losses, particularly in salmonids. Iron is an essential nutrient for many cellular processes and is involved in host sensing and virulence regulation in many bacteria. Bacterial pathogens diff...

Clinical and Prognostic Importance of Serotyping Mycobacterium avium-Mycobacterium intracellulare Complex Isolates in Human Immunodeficiency Virus-Negative Patients

PubMed Central

Maekura, Ryoji; Okuda, Yoshinari; Hirotani, Atsusi; Kitada, Seigo; Hiraga, Touru; Yoshimura, Kenji; Yano, Ikuya; Kobayashi, Kazuo; Ito, Masami

2005-01-01

We studied whether the serotypes of Mycobacterium avium-Mycobacterium intracellulare complex (MAC) isolates determine the prognosis for pulmonary MAC disease. We prospectively monitored a cohort of 68 patients with pulmonary MAC disease for whom the serotype-specific glycopeptidolipids in isolates were identified using thin-layer chromatography and fast atom bombardment mass-spectrometry in 1990 and 1995. Serovar 4 Mycobacterium avium was detected in 40/68 patients (58.8%). Other serotypes were serotypes 1 (five cases), 6 (three cases), 8 (seven cases), 9 (three cases), 14 (four cases), and 16 (six cases). Patients with serovar 4 were significantly (P < 0.01) younger (63.0 ± 9.8 years) than patients with other serotypes (71.8 ± 10.3). Patients who failed treatment had a significantly poorer prognosis than other patients. There were no cases of MAC-related death in the cured group. Chest radiographic findings progressively worsened in 36 (90%) of patients with serotype 4, and 14/36 died from respiratory failure caused by pulmonary Mycobacterium avium disease. The patients with serotype 4 had a significantly poorer prognosis than patients with other serotypes. These results show that both the outcome of chemotherapy and the serotypes of MAC isolates are important for assessing the prognosis of pulmonary MAC disease. PMID:16000428

Vibrio parahaemolyticus Strains of Pandemic Serotypes Identified from Clinical and Environmental Samples from Jiangsu, China

PubMed Central

Li, Jingjiao; Xue, Feng; Yang, Zhenquan; Zhang, Xiaoping; Zeng, Dexin; Chao, Guoxiang; Jiang, Yuan; Li, Baoguang

2016-01-01

Vibrio parahaemolyticus has emerged as a major foodborne pathogen in China, Japan, Thailand, and other Asian countries. In this study, 72 strains of V. parahaemolyticus were isolated from clinical and environmental samples between 2006 and 2014 in Jiangsu, China. The serotypes and six virulence genes including thermostable direct hemolysin (TDR) and TDR-related hemolysin (TRH) genes were assessed among the isolates. Twenty five serotypes were identified and O3:K6 was one of the dominant serotypes. The genetic diversity was assessed by multilocus sequence typing (MLST) analysis, and 48 sequence types (STs) were found, suggesting this V. parahaemolyticus group is widely dispersed and undergoing rapid evolution. A total of 25 strains of pandemic serotypes such as O3:K6, O5:K17, and O1:KUT were identified. It is worth noting that the pandemic serotypes were not exclusively identified from clinical samples, rather, nine strains were also isolated from environmental samples; and some of these strains harbored several virulence genes, which may render those strains pathogenicity potential. Therefore, the emergence of these “environmental” pandemic V. parahaemolyticus strains may poses a new threat to the public health in China. Furthermore, six novel serotypes and 34 novel STs were identified among the 72 isolates, indicating that V. parahaemolyticus were widely distributed and fast evolving in the environment in Jiangsu, China. The findings of this study provide new insight into the phylogenic relationship between V. parahaemolyticus strains of pandemic serotypes from clinical and environmental sources and enhance the MLST database; and our proposed possible O- and K- antigen evolving paths of V. parahaemolyticus may help understand how the serotypes of this dispersed bacterial population evolve. PMID:27303379

Yersinia pestis Biofilm in the Flea Vector and Its Role in the Transmission of Plague

PubMed Central

Erickson, D. L.

2013-01-01

Transmission by fleabite is a relatively recent evolutionary adaptation of Yersinia pestis, the bacterial agent of bubonic plague. To produce a transmissible infection, Y. pestis grows as an attached biofilm in the foregut of the flea vector. Biofilm formation both in the flea foregut and in vitro is dependent on an extracellular matrix (ECM) synthesized by the Yersinia hms gene products. The hms genes are similar to the pga and ica genes of Escherichia coli and Staphylococcus epidermidis, respectively, that act to synthesize a poly-β-1,6-N-acetyl-d-glucosamine ECM required for biofilm formation. As with extracellular polysaccharide production in many other bacteria, synthesis of the Hms-dependent ECM is controlled by intracellular levels of cyclic-di-GMP. Yersinia pseudotuberculosis, the food- and water-borne enteric pathogen from which Y. pestis evolved recently, possesses identical hms genes and can form biofilm in vitro but not in the flea. The genetic changes in Y. pestis that resulted in adapting biofilm-forming capability to the flea gut environment, a critical step in the evolution of vector-borne transmission, have yet to be identified. During a flea bite, Y. pestis is regurgitated into the dermis in a unique biofilm phenotype, and this has implications for the initial interaction with the mammalian innate immune response. PMID:18453279

Comparing inactivation protocols of Yersinia organisms for identification with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.

PubMed

Couderc, Carine; Nappez, Claude; Drancourt, Michel

2012-03-30

It is recommended that harmful Biosafety Level 3 (BSL-3) bacteria be inactivated prior to identification by mass spectrometry, yet optimal effects of inactivation protocol have not been defined. Here, we compare trifluoroacetic acid inactivation (protocol A) with ethanol inactivation (protocol B) of Yersinia organisms prior to identification by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). The total number of peaks detected was 10.5 ± 1.7 for protocol A and 15.7 ± 4.2 for protocol B (ρ <0.001, ANOVA test). The signal-to-noise ratio for the m/z 6049 peak present in all of the tested Yersinia isolates was 9.7 ± 3.1 for protocol A and 18.1 ± 4.6 for protocol B (ρ < 0.001). Compared with spectra in our local database containing 48 Yersinia spp., including 20 strains of Y. pestis, the identification score was 1.79 ± 0.2 for protocol A and 1.97 ± 0.19 for protocol B (ρ = 0.0024). Our observations indicate that for the identification of Yersinia organisms, ethanol inactivation yielded MALDI-TOF-MS spectra of significantly higher quality than spectra derived from trifluoroacetic acid inactivation. Combined with previously published data, our results permit the updating of protocols for inactivating BSL-3 bacteria. Copyright © 2012 John Wiley & Sons, Ltd.

Autodisplay: Development of an Efficacious System for Surface Display of Antigenic Determinants in Salmonella Vaccine Strains

PubMed Central

Kramer, Uwe; Rizos, Konstantin; Apfel, Heiko; Autenrieth, Ingo B.; Lattemann, Claus T.

2003-01-01

To optimize antigen delivery by Salmonella vaccine strains, a system for surface display of antigenic determinants was established by using the autotransporter secretion pathway of gram-negative bacteria. A modular system for surface display allowed effective targeting of heterologous antigens or fragments thereof to the bacterial surface by the autotransporter domain of AIDA-I, the Escherichia coli adhesin involved in diffuse adherence. A major histocompatibility complex class II-restricted epitope, comprising amino acids 74 to 86 of the Yersinia enterocolitica heat shock protein Hsp60 (Hsp6074-86), was fused to the AIDA-I autotransporter domain, and the resulting fusion protein was expressed at high levels on the cell surface of E. coli and Salmonella enterica serovar Typhimurium. Colonization studies in mice vaccinated with Salmonella strains expressing AIDA-I fusion proteins demonstrated high genetic stability of the generated vaccine strain in vivo. Furthermore, a pronounced T-cell response against Yersinia Hsp6074-86 was induced in mice vaccinated with a Salmonella vaccine strain expressing the Hsp6074-86-AIDA-I fusion protein. This was shown by monitoring Yersinia Hsp60-stimulated IFN-γ secretion and proliferation of splenic T cells isolated from vaccinated mice. These results demonstrate that the surface display of antigenic determinants by the autotransporter pathway deserves special attention regarding the application in live attenuated Salmonella vaccine strains. PMID:12654812

Autodisplay: development of an efficacious system for surface display of antigenic determinants in Salmonella vaccine strains.

PubMed

Kramer, Uwe; Rizos, Konstantin; Apfel, Heiko; Autenrieth, Ingo B; Lattemann, Claus T

2003-04-01

To optimize antigen delivery by Salmonella vaccine strains, a system for surface display of antigenic determinants was established by using the autotransporter secretion pathway of gram-negative bacteria. A modular system for surface display allowed effective targeting of heterologous antigens or fragments thereof to the bacterial surface by the autotransporter domain of AIDA-I, the Escherichia coli adhesin involved in diffuse adherence. A major histocompatibility complex class II-restricted epitope, comprising amino acids 74 to 86 of the Yersinia enterocolitica heat shock protein Hsp60 (Hsp60(74-86)), was fused to the AIDA-I autotransporter domain, and the resulting fusion protein was expressed at high levels on the cell surface of E. coli and Salmonella enterica serovar Typhimurium. Colonization studies in mice vaccinated with Salmonella strains expressing AIDA-I fusion proteins demonstrated high genetic stability of the generated vaccine strain in vivo. Furthermore, a pronounced T-cell response against Yersinia Hsp60(74-86) was induced in mice vaccinated with a Salmonella vaccine strain expressing the Hsp60(74-86)-AIDA-I fusion protein. This was shown by monitoring Yersinia Hsp60-stimulated IFN-gamma secretion and proliferation of splenic T cells isolated from vaccinated mice. These results demonstrate that the surface display of antigenic determinants by the autotransporter pathway deserves special attention regarding the application in live attenuated Salmonella vaccine strains.

Tularemia, plague, yersiniosis, and Tyzzer’s disease in wild rodents and lagomorphs in Canada: A review

PubMed Central

Wobeser, Gary; Campbell, G. Douglas; Dallaire, André; McBurney, Scott

2009-01-01

Information related to infection of wild rodents or lagomorphs in Canada by Francisella tularensis, Yersinia pestis, other Yersinia spp., and Clostridium piliforme was searched for this study. Reports on tularemia in humans linked to these species came from diagnostic databases, literature, wildlife health specialists, and public health agencies. Tularemia has been diagnosed in 8 species of wild rodent and 2 species in the genus Lepus in Canada. Tularemia occurred in wild animals, or in humans associated with these species, in all jurisdictions except the Yukon and Nunavut. Tularemia was diagnosed most frequently in beaver, muskrats, and snowshoe hares, and although tularemia is closely linked to cottontail rabbits in the USA, it has not been reported in cottontails in Canada. Tularemia in humans was associated with muskrats and hares more commonly than with beaver. Plague was diagnosed in bushy-tailed woodrats in British Columbia in 1988. Based on surveys, Y. pestis may occur enzootically in southern Alberta, Saskatchewan, and British Columbia. Infection with Yersinia pseudotuberculosis and Y. enterocolitica has been diagnosed in beaver, muskrats, and snowshoe hares in many provinces. Tyzzer’s disease has been diagnosed in muskrats in British Columbia, Saskatchewan, Ontario, and Quebec and in snowshoe hares in Ontario. Infection with these bacteria is likely much more frequent than indicated by diagnostic records. PMID:20190973

Streptococcus mutans levels in saliva and distribution of serotypes among 9-year-old Icelandic children.

PubMed

Holbrook, W P; Beighton, D

1987-02-01

Streptococcus mutans levels in saliva were determined in 9-yr-old children from five towns in Iceland. In four towns the mean counts were greater than 10(5)/ml. Serotype c was predominant but types e and d/g were also found. The proportion of children harbouring serotype d/g alone or in combination with other serotypes was higher than that reported in most other studies.

Major tdh(+)Vibrio parahaemolyticus serotype changes temporally in the Bay of Bengal estuary of Bangladesh.

PubMed

Akther, Farhana; Neogi, Sucharit Basu; Chowdhury, Wasimul B; Sadique, Abdus; Islam, Atiqul; Akhter, Marufa Zerin; Johura, Fatema-Tuz; Ohnishi, Makoto; Watanabe, Haruo; Boucher, Yan; Alam, Munirul

2016-07-01

Vibrio parahaemolyticus is responsible for seafood-related gastroenteritis worldwide. In Bangladesh, diarrhea is endemic and diarrheagenic V. parahaemolyticus serotypes occur naturally in the coastal and estuarine aquatic environment. V. parahaemolyticus strains, isolated from estuarine surface water of the Bay of Bengal villages of Bangladesh during 2006-2008, were tested for the presence of virulence and pandemic-marker genes, serodiversity, and phylogenetic relatedness. PCR analysis of V. parahaemolyticus (n=175) showed 53 (30.3%) strains to possess tdh, the major virulence gene encoding thermostable direct hemolysin. Serotyping results revealed the tdh(+)V. parahaemolyticus strains to belong to 10 different serotypes, of which the O8:K21 (30.2%) and O3:K6 (24.5%) were predominantly non-pandemic and pandemic serotypes, respectively; while O5:K30 and O9:KUT were new. The pandemic markers, orf8 and toxRS(variant), were present only in the pandemic serotype O3:K6 (n=13) and its serovariant O4:K68 (n=2). Temporal distribution of the tdh(+) serotypes revealed the O8:K21 to be predominant in 2006 and 2007, while O3:K6 was the predominant tdh(+) serotype in 2008. Pulsed-field gel electrophoresis (PFGE) of SfiI-digested genomic DNA revealed high genetic diversity among the V. parahaemolyticus strains, while dendrogram constructed with the PFGE patterns formed two major clusters separating the tdh(+) O3:K6 and its pandemic serovariants from the tdh(+) non-pandemic (O8:K21) strains, suggesting different lineages for them. The potential health risk related to the prevalent tdh(+) strains, including the observed temporal change of the predominant tdh(+) serotype, from O8:K21 to the pandemic serotype O3:K6 in estuarine surface waters serving as the major source of drinking water suggests the need for routine environmental monitoring to prevent V. parahaemolyticus infection in Bangladesh. Copyright © 2016. Published by Elsevier B.V.

Detection of dengue virus serotypes 1, 2 and 3 in selected regions of Kenya: 2011-2014.

PubMed

Konongoi, Limbaso; Ofula, Victor; Nyunja, Albert; Owaka, Samuel; Koka, Hellen; Makio, Albina; Koskei, Edith; Eyase, Fredrick; Langat, Daniel; Schoepp, Randal J; Rossi, Cynthia Ann; Njeru, Ian; Coldren, Rodney; Sang, Rosemary

2016-11-04

Dengue fever, a mosquito-borne disease, is associated with illness of varying severity in countries in the tropics and sub tropics. Dengue cases continue to be detected more frequently and its geographic range continues to expand. We report the largest documented laboratory confirmed circulation of dengue virus in parts of Kenya since 1982. From September 2011 to December 2014, 868 samples from febrile patients were received from hospitals in Nairobi, northern and coastal Kenya. The immunoglobulin M enzyme linked immunosorbent assay (IgM ELISA) was used to test for the presence of IgM antibodies against dengue, yellow fever, West Nile and Zika. Reverse transcription polymerase chain reaction (RT-PCR) utilizing flavivirus family, yellow fever, West Nile, consensus and sero type dengue primers were used to detect acute arbovirus infections and determine the infecting serotypes. Representative samples of PCR positive samples for each of the three dengue serotypes detected were sequenced to confirm circulation of the various dengue serotypes. Forty percent (345/868) of the samples tested positive for dengue by either IgM ELISA (14.6 %) or by RT-PCR (25.1 %). Three dengue serotypes 1-3 (DENV1-3) were detected by serotype specific RT-PCR and sequencing with their numbers varying from year to year and by region. The overall predominant serotype detected from 2011-2014 was DENV1 accounting for 44 % (96/218) of all the serotypes detected, followed by DENV2 accounting for 38.5 % (84/218) and then DENV3 which accounted for 17.4 % (38/218). Yellow fever, West Nile and Zika was not detected in any of the samples tested. From 2011-2014 serotypes 1, 2 and 3 were detected in the Northern and Coastal parts of Kenya. This confirmed the occurrence of cases and active circulation of dengue in parts of Kenya. These results have documented three circulating serotypes and highlight the need for the establishment of active dengue surveillance to continuously detect cases, circulating

Retracing the Evolutionary Path that Led to Flea-borne Transmission of Yersinia pestis

PubMed Central

Sun, Yi-Cheng; Jarrett, Clayton O.; Bosio, Christopher F.; Hinnebusch, B. Joseph

2014-01-01

Summary Yersinia pestis is an arthropod-borne bacterial pathogen that evolved recently from Yersinia pseudotuberculosis, an enteric pathogen transmitted via the fecal-oral route. This radical ecological transition can be attributed to a few discrete genetic changes from a still-extant recent ancestor, thus providing a tractable case study in pathogen evolution and emergence. Here, we determined the precise genetic and mechanistic basis of the evolutionary adaptation of Y. pestis to flea-borne transmission. Remarkably, only four minor changes in the bacterial progenitor, representing one gene gain and three gene losses, enabled transmission by flea vectors. All three loss-of-function mutations enhanced c-di-GMP-mediated bacterial biofilm formation in the flea foregut that greatly increased transmissibility. Our results suggest a step-wise evolutionary model in which Y. pestis emerged as a flea-borne clone, with each genetic change incrementally reinforcing the transmission cycle. The model conforms well to the ecological theory of adaptive radiation. PMID:24832452

Retracing the evolutionary path that led to flea-borne transmission of Yersinia pestis.

PubMed

Sun, Yi-Cheng; Jarrett, Clayton O; Bosio, Christopher F; Hinnebusch, B Joseph

2014-05-14

Yersinia pestis is an arthropod-borne bacterial pathogen that evolved recently from Yersinia pseudotuberculosis, an enteric pathogen transmitted via the fecal-oral route. This radical ecological transition can be attributed to a few discrete genetic changes from a still-extant recent ancestor, thus providing a tractable case study in pathogen evolution and emergence. Here, we determined the genetic and mechanistic basis of the evolutionary adaptation of Y. pestis to flea-borne transmission. Remarkably, only four minor changes in the bacterial progenitor, representing one gene gain and three gene losses, enabled transmission by flea vectors. All three loss-of-function mutations enhanced cyclic-di-GMP-mediated bacterial biofilm formation in the flea foregut, which greatly increased transmissibility. Our results suggest a step-wise evolutionary model in which Y. pestis emerged as a flea-borne clone, with each genetic change incrementally reinforcing the transmission cycle. The model conforms well to the ecological theory of adaptive radiation. Copyright © 2014 Elsevier Inc. All rights reserved.

Pulmonary infection by Yersinia pestis rapidly establishes a permissive environment for microbial proliferation.

PubMed

Price, Paul A; Jin, Jianping; Goldman, William E