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...

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.

Loop-mediated isothermal amplification as an emerging technology for detection of Yersinia ruckeri the causative agent of enteric red mouth disease in fish.

PubMed

Saleh, Mona; Soliman, Hatem; El-Matbouli, Mansour

2008-08-12

Enteric Redmouth (ERM) disease also known as Yersiniosis is a contagious disease affecting salmonids, mainly rainbow trout. The causative agent is the gram-negative bacterium Yersinia ruckeri. The disease can be diagnosed by isolation and identification of the causative agent, or detection of the Pathogen using fluorescent antibody tests, ELISA and PCR assays. These diagnostic methods are laborious, time consuming and need well trained personnel. A loop-mediated isothermal amplification (LAMP) assay was developed and evaluated for detection of Y. ruckeri the etiological agent of enteric red mouth (ERM) disease in salmonids. The assay was optimised to amplify the yruI/yruR gene, which encodes Y. ruckeri quorum sensing system, in the presence of a specific primer set and Bst DNA polymerase at an isothermal temperature of 63 degrees C for one hour. Amplification products were detected by visual inspection, agarose gel electrophoresis and by real-time monitoring of turbidity resulted by formation of LAMP amplicons. Digestion with HphI restriction enzyme demonstrated that the amplified product was unique. The specificity of the assay was verified by the absence of amplification products when tested against related bacteria. The assay had 10-fold higher sensitivity compared with conventional PCR and successfully detected Y. ruckeri not only in pure bacterial culture but also in tissue homogenates of infected fish. The ERM-LAMP assay represents a practical alternative to the microbiological approach for rapid, sensitive and specific detection of Y. ruckeri in fish farms. The assay is carried out in one hour and needs only a heating block or water bath as laboratory furniture. The advantages of the ERM-LAMP assay make it a promising tool for molecular detection of enteric red mouth disease in fish farms.

Antimicrobial peptide CAP18 and its effect on Yersinia ruckeri infections in rainbow trout Oncorhynchus mykiss (Walbaum): comparing administration by injection and oral routes.

PubMed

Chettri, J K; Mehrdana, F; Hansen, E B; Ebbensgaard, A; Overgaard, M T; Lauritsen, A H; Dalsgaard, I; Buchmann, K

2017-01-01

The antimicrobial peptide CAP18 has been demonstrated to have a strong in vitro bactericidal effect on Yersinia ruckeri, but its activity in vivo has not been described. In this work, we investigated whether CAP18 protects rainbow trout Oncorhynchus mykiss (Walbaum) against enteric red mouth disease caused by this pathogen either following i.p. injection or by oral administration (in feed). It was found that injection of CAP18 into juvenile rainbow trout before exposure to Y. ruckeri was associated with lowered mortality compared to non-medicated fish although it was less effective than the conventional antibiotic oxolinic acid. Oral administration of CAP18 to trout did not prevent infection. The proteolytic effect of secretions on the peptide CAP18 in the fish gastrointestinal tract is suggested to account for the inferior effect of oral administration. © 2016 John Wiley & Sons Ltd.

Global 3D Imaging of Yersinia ruckeri Bacterin Uptake in Rainbow Trout Fry

PubMed Central

Ohtani, Maki; Villumsen, Kasper Rømer; Koppang, Erling Olaf; Raida, Martin Kristian

2015-01-01

Yersinia ruckeri is the causative agent of enteric redmouth disease (ERM) in rainbow trout, and the first commercially available fish vaccine was an immersion vaccine against ERM consisting of Y. ruckeri bacterin. The ERM immersion vaccine has been successfully used in aquaculture farming of salmonids for more than 35 years. The gills and the gastrointestinal (GI) tract are believed to be the portals of antigen uptake during waterborne vaccination against ERM; however, the actual sites of bacterin uptake are only partly understood. In order to obtain insight into bacterin uptake during waterborne vaccination, optical projection tomography (OPT) together with immunohistochemistry (IHC) was applied to visualize bacterin uptake and processing in whole rainbow trout fry. Visualization by OPT revealed that the bacterin was initially taken up via gill lamellae from within 30 seconds post vaccination. Later, bacterin uptake was detected on other mucosal surfaces such as skin and olfactory bulb from 5 to 30 minutes post vaccination. The GI tract was found to be filled with a complex of bacterin and mucus at 3 hours post vaccination and the bacterin remained in the GI tract for at least 24 hours. Large amounts of bacterin were present in the blood, and an accumulation of bacterin was found in filtering lymphoid organs such as spleen and trunk kidney where the bacterin accumulates 24 hours post vaccination as demonstrated by OPT and IHC. These results suggest that bacterin is taken up via the gill epithelium in the earliest phases of the bath exposure and from the GI tract in the later phase. The bacterin then enters the blood circulatory system, after which it is filtered by spleen and trunk kidney, before finally accumulating in lymphoid organs where adaptive immunity against ERM is likely to develop. PMID:25658600

Optimization of nested polymerase chain reaction assays for identification of Aeromonas salmonicida, Yersinia ruckeri and Flavobacterium psychrophilum

USGS Publications Warehouse

Taylor, P.W.; Winton, J.R.

2002-01-01

Nested polymerase chain reaction (PCR) assays were developed using first-round primers complementary to highly conserved regions within the bacterial 16S ribosomal RNA (rRNA) gene (universal eubacterial primers) and second-round primers specific for sequences within the 16S rRNA genes of Aeromonas salmonicida, Yersinia ruckeri, andFlavobacterium psychrophilum. Following optimization of the MgCl2 concentration and primer annealing temperature, PCR employing the universal eubacterial primers was used to amplify a 1,500-base-pair (bp) product visible in agarose gels stained with ethidium bromide. The calculated detection limit of this single-round assay was less than 1.4 × 104 colony-forming units (CFU) per reaction for all bacterial species tested. Single-round PCR using primer sets specific for A. salmonicida, Y. ruckeri, and F. psychrophilumamplified bands of 271, 575, and 1,100 bp, respectively, with detection limits of less than 1.4 × 104, 1.4 × 105, and 1.4 × 105 CFU per reaction. Using the universal eubacterial primers in the first round and the species-specific primer sets in the second round of nested PCR assays improved the detection ability by approximately four orders of magnitude to fewer than 14 CFU per sample for each of the three bacterial species. Such nested assays could be adapted to a wide variety of bacterial fish pathogens for which 16S sequences are available.

Effects of Different Levels of Pomegranate Seed Oil on Some Blood Parameters and Disease Resistance Against Yersinia ruckeri in Rainbow Trout

PubMed Central

Acar, Ümit; Parrino, Vincenzo; Kesbiç, Osman Sabri; Lo Paro, Giuseppe; Saoca, Concetta; Abbate, Francesco; Yılmaz, Sevdan; Fazio, Francesco

2018-01-01

This study is aimed to assess the effects of pomegranate seed oil (PSO) supplementation on growth performance, some hematological, biochemical and immunological parameters, and disease resistance against Yersinia ruckeri in cultured rainbow trout Oncorhynchus mykiss (Walbaum, 1792). 240 fish in total were randomly assigned into four triplicate groups (20 fish/per aquarium) corresponding to four dietary treatments: control (PSO0; no addition of PSO), 0.5% (PSO5), 1.00% (PSO10), and 2.00% (PSO20) of PSO, respectively. After the 60 day-feeding trial, fish blood samples were collected and compared. Statistical analysis (one-way ANOVA) showed a significant (P < 0.05) effect of PSO on red blood cell count, hemoglobin concentration, mean corpuscular volume, mean corpuscular hemoglobin concentration, cholesterol, aspartate aminotransferase, alanine aminotransferase, and alkaline phosphatase parameters in PSO5 and PSO10 with regard to control. Moreover, a pronounced (P < 0.05) increased in weight gain, growth and feed conversion was found in fish fed with PSO supplemented diets. After the feeding trial, fish were challenged with Y. ruckeri and survival recorded for 20 days. Cumulative survival was 45.10% in fish fed with the control diet, whereas in fish fed with PSO5, PSO10, and PSO20 supplemented diets, survival was 58.82, 56.86, and 56.86%, respectively. In conclusion, dietary administration of PSO induced a reduction in mortality of rainbow trout infected with Y. ruckeri, intercalary significant differences occurred on growth performance and some blood values among treated groups. These positive effects of PSO could be considered for new applications in aquaculture. PMID:29875694

Pulsed-field gel electrophoresis and multi locus sequence typing for characterizing genotype variability of Yersinia ruckeri isolated from farmed fish in France.

PubMed

Calvez, Ségolène; Fournel, Catherine; Douet, Diane-Gaëlle; Daniel, Patrick

2015-06-23

Yersinia ruckeri is a pathogen that has an impact on aquaculture worldwide. The disease caused by this bacterial species, yersiniosis or redmouth disease, generates substantial economic losses due to the associated mortality and veterinary costs. For predicting outbreaks and improving control strategies, it is important to characterize the population structure of the bacteria. The phenotypic and genetic homogeneities described previously indicate a clonal population structure as observed in other fish bacteria. In this study, the pulsed-field gel electrophoresis (PFGE) and multi locus sequence typing (MLST) methods were used to describe a population of isolates from outbreaks on French fish farms. For the PFGE analysis, two enzymes (NotI and AscI) were used separately and together. Results from combining the enzymes showed the great homogeneity of the outbreak population with a similarity > 80.0% but a high variability within the cluster (cut-off value = 80.0%) with a total of 43 pulsotypes described and an index of diversity = 0.93. The dominant pulsotypes described with NotI (PtN4 and PtN7) have already been described in other European countries (Finland, Germany, Denmark, Spain and Italy). The MLST approach showed two dominant sequence types (ST31 and ST36), an epidemic structure of the French Y. ruckeri population and a preferentially clonal evolution for rainbow trout isolates. Our results point to multiple types of selection pressure on the Y. ruckeri population attributable to geographical origin, ecological niche specialization and movements of farmed fish.

Effect of oral booster vaccination of rainbow trout against Yersinia ruckeri depends on type of primary immunization.

PubMed

Jaafar, Rzgar M; Al-Jubury, Azmi; Dalsgaard, Inger; MohammadKarami, Asma; Kania, Per W; Buchmann, Kurt

2017-10-31

Vaccination of rainbow trout against Enteric Redmouth Disease (ERM) caused by Yersinia ruckeri can be successfully performed by administering vaccine (a bacterin consisting of formalin killed bacteria) by immersion, bath or injection. Booster immunization is known to increase the protection of fish already primed by one of these vaccination methods. Oral vaccination of trout (administering vaccine in feed) is an even more convenient way of presenting antigen to the fish but the effect of an oral booster has not previously been described in detail. The present work describes to what extent protection may be enhanced by oral boostering following priming with different administration methods. The study confirms that vaccination by 30 s dip into a bacterin (diluted 1:10) may confer a significant protection compared to non-vaccinated fish. The immunity may be optimized by booster immunization either provided as dip (most effective), bath (less effective) or orally (least effective). Oral immunization may be used as booster after dip but applied as a single oral application it induced merely a slight and statistically non-significant response. It is noteworthy that primary oral immunization followed by an oral booster vaccination showed a trend for an even weaker response. It should be investigated if continued exposure to a low antigen concentration - as performed by two oral immunizations - may induce tolerance to the pathogen and thereby leave the fish more vulnerable. Copyright © 2017 Elsevier Ltd. All rights reserved.

Comparative susceptibility of channel catfish, Ictalurus punctatus; blue catfish, Ictalurus furcatus; and channel female Blue male Hybrid catfish to Edwardsiella piscicida, Edwardsiella tarda, and Edwardsiella anguillarum

USDA-ARS?s Scientific Manuscript database

Members of the genus Edwardsiella are important pathogens of cultured and wild fish globally. Recent investigations into the phenotypic and genotypic variation of Edwardsiella tarda have led to the segregation of E. tarda into three distinct taxa: E. tarda, Edwardsiella piscicida, and Edwardsiella a...

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®

Hemato - Immunological and biochemical parameters, skin antibacterial activity, and survival in rainbow trout (Oncorhynchus mykiss) following the diet supplemented with Mentha piperita against Yersinia ruckeri.

PubMed

Adel, Milad; Pourgholam, Reza; Zorriehzahra, Jalil; Ghiasi, Maryam

2016-08-01

This study was aimed to assess the potential effects of Mentha piperita on the hemato - immunological and biochemical parameters, skin antibacterial activity and protection against Yersinia ruckeri infection in rainbow trout Oncorhynchus mykiss. Fish were divided into 4 groups before being fed diets supplemented with 0, 1, 2 and 3% of Mentha piperita (MP) plant extract for 8 weeks. Dose-dependent increases immune (both in skin mucus and blood serum) and hematological parameters (number of red and white cells, hematocrit and hemoglobin contents), as well as in respiratory burst activity, total protein, albumin, and neutrophil levels in fish fed supplemented diets compared to the control fish. Furthermore, dietary MP plant extract supplements have no significant effect on blood biochemical parameters and enzymatic activities of liver determined in serum of rainbow trout. After 8 weeks the cessation of feeding with MP plant extract, survival rates of 54.4%, 63.6% and 75.2% were recorded in groups which received 1, 2 and 3% of MP plant extract of feed, respectively, compared to 34.6% survivals in the control. This study underlying several positive effects of dietary administration of MP plant extract to farmed fish. Copyright © 2016 Elsevier Ltd. All rights reserved.

Efficacy testing of a 35 year old commercially produced Yersinia ruckeri bacterin for the control of Enteric Redmouth ERM) Disease

USDA-ARS?s Scientific Manuscript database

In 1976 the United States Department of Agriculture, Veterinary Services, granted the first veterinary product license for a biologic to be administered to fish. That license was issued for Enteric Redmouth Bacterin (Yerisina ruckeri) to the first commercial fish vaccine company, Wildlife Vaccines. ...

Isolation of Edwardsiella tarda from Swine

PubMed Central

Owens, Dwight R.; Nelson, Stuart L.; Addison, J. Bruce

1974-01-01

Edwardsiella tarda was isolated from the intestinal tract of a 2-month-old pig. This is the first reported isolation of Edwardsiella tarda from swine in the United States. Swine have been reported as potential carriers of Edwardsiella tarda, but pathogenicity of this organism for swine has not been determined. Although the pig had access to several farm ponds, the exact source of infection was not determined. PMID:4825978

Complete genome sequence of Yersinia ruckeri str. CSF007-82, etiologic agent of enteric redmouth disease in salmonid fish

USDA-ARS?s Scientific Manuscript database

We present the complete, closed and finished chromosomal and extra-chromosomal genome sequences of Y. ruckeri strain CSF007-82, etiologic agent of enteric red mouth disease in salmonid fish. The chromosome is 3,799,036 bp with a G+C content of 47.5% and encodes 3,530 predicted CDS, 7 ribosomal opero...

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.

In vitro assessment of the antimicrobial activity of silver and zinc oxide nanoparticles against fish pathogens.

PubMed

Shaalan, Mohamed Ibrahim; El-Mahdy, Magdy Mohamed; Theiner, Sarah; El-Matbouli, Mansour; Saleh, Mona

2017-07-21

Antibiotic resistance is a global issue that threatens public health. The excessive use of antibiotics contributes to this problem as the genes of antibiotic resistance can be transferred between the bacteria in humans, animals and aquatic organisms. Metallic nanoparticles could serve as future substitutes for some conventional antibiotics because of their antimicrobial activity. The aim of this study was to evaluate the antimicrobial effects of silver and zinc oxide nanoparticles against major fish pathogens and assess their safety in vitro. Silver nanoparticles were synthesized by chemical reduction and characterized with UV-Vis spectroscopy, transmission electron microscopy and zeta sizer. The concentrations of silver and zinc oxide nanoparticles were measured using inductively coupled plasma-mass spectrometry. Subsequently, silver and zinc oxide nanoparticles were tested for their antimicrobial activity against Aeromonas hydrophila, Aeromonas salmonicida subsp. salmonicida, Edwardsiella ictaluri, Edwardsiella tarda, Francisella noatunensis subsp. orientalis, Yersinia ruckeri and Aphanomyces invadans and the minimum inhibitory concentrations were determined. MTT assay was performed on eel kidney cell line (EK-1) to determine the cell viability after incubation with nanoparticles. The interaction between silver nanoparticles and A. salmonicida was investigated by transmission electron microscopy. The tested nanoparticles exhibited marked antimicrobial activity. Silver nanoparticles inhibited the growth of both A. salmonicida and A. invadans at a concentration of 17 µg/mL. Zinc oxide nanoparticles inhibited the growth of A. salmonicida, Y. ruckeri and A. invadans at concentrations of 15.75, 31.5 and 3.15 µg/mL respectively. Silver nanoparticles showed higher cell viability when compared to zinc oxide nanoparticles in the MTT assay. Transmission electron microscopy showed the attachment of silver nanoparticles to the bacterial membrane and disruption of its

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

Edwardsiella piscicida-like pathogen in cultured grouper.

PubMed

Ucko, Michal; Colorni, Angelo; Dubytska, Lidiya; Thune, Ronald L

2016-09-26

An Edwardsiella sp. was isolated from the kidney of diseased groupers (Epinephelus aeneus and E. marginatus) cultured in Eilat (Israel, Red Sea). Affected fish presented a severe suppurative nephritis with large abscesses occasionally spreading into the surrounding musculature. Biochemical profiles and phenotypic comparisons failed to provide a clear identification to the species level, and genetic analysis of the 16S subunit failed to discriminate between Edwardsiella piscicida, E. tarda and E. ictaluri. Analysis of the gyrB gene, however, placed the grouper isolates into the E. piscicida-like group, a newly recognized taxon which also encompasses the non-motile strains previously classified as atypical E. tarda. Initial genomic analysis revealed the presence of the Edwardsiella type 3 secretion system (T3SS) but also revealed a pathogenicity island encoding a second T3SS with homology to the locus of enterocyte effacement of Escherichia coli. Further analysis revealed 3 different type 6 secretion systems that were also present in all sequenced isolates of Edwardsiella piscicida-like strains. Based on estimated DNA-DNA hybridization values and the average nucleotide index, the grouper strain fits into the E. piscicida-like phylogroup described as E. anguillarum sp. nov. The peculiarities associated with this isolate and the association of other conspecific piscine isolates from multiple marine and brackish water species suggest a link of the entire E. piscicida-like phylogroup to the marine environment.

Real-time PCR assays for detection and quactification of Edwardsiella tarda, Edwardsiella piscicida, Edwardsiella piscicida-like sp. in catfish tissues and pond water

USDA-ARS?s Scientific Manuscript database

Researchers have proposed the adoption of 3 distinct genetic taxa among bacteria previously classified as Edwardsiella tarda; namely E. tarda, E. piscicida, and a taxon presently termed E. piscicida–like. Individual real-time polymerase chain reaction (qPCR) assays were developed, based on published...

Population genetic and evolution analysis of controversial genus Edwardsiella by multilocus sequence typing.

PubMed

Buján, Noemí; Balboa, Sabela; L Romalde, Jesús; E Toranzo, Alicia; Magariños, Beatriz

2018-05-08

At present, the genus Edwardsiella compiles five species: E. tarda, E. hoshinae, E. ictaluri, E. piscicida and E. anguillarum. Some species of this genus such us E. ictaluri and E. piscicida are important pathogens of numerous fish species. With the description of the two latter species, the phylogeny of Edwardsiella became more complicated. With the aim to clarify the relationships among all species in the genus, a multilocus sequence typing (MLST) approach was developed and applied to characterize 56 isolates and 6 reference strains belonging to the five Edwardsiella species. Moreover, several analyses based on the MLST scheme were performed to investigate the evolution within the genus, as well as the influence of recombination and mutation in the speciation. Edwardsiella isolates presented a high genetic variability reflected in the fourteen sequence types (ST) represented by a single isolates out of eighteen total ST. Mutation events were considerably more frequent than recombination, although both approximately equal influenced the genetic diversification. However, the speciation among species occurred mostly by recombination. Edwardsiella genus displays a non-clonal population structure with some degree of geographical isolation followed by a population expansion of E. piscicida. A database from this study was created and hosted on pubmlst.org (http://pubmlst.org/edwardsiella/). Copyright © 2018 Elsevier Inc. All rights reserved.

Pathogen Screening of Naturally Produced Yakima River Spring Chinook Smolts; Yakima/Klickitat Fisheries Project Monitoring and Evaluation Report 6 of 7, 2003-2004 Annual Report.

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

Thomas, Joan B.

2004-05-01

In 1999 the Cle Elum Hatchery began releasing spring chinook salmon smolts into the upper Yakima River to increase natural production. Part of the evaluation of this program is to monitor whether introduction of hatchery produced smolts would impact the prevalence of specific pathogens in the naturally produced spring chinook smolts. Increases in prevalence of any of these pathogens could negatively impact the survival of these fish. In 1998 and 2000 through 2003 naturally produced smolts were collected for monitoring at the Chandler smolt collection facility on the lower Yakima River. Smolts were collected from mid to late outmigration, withmore » a target of 200 fish each year. The pathogens monitored were infectious hematopoeitic necrosis virus, infectious pancreatic necrosis virus, viral hemorrhagic septicemia virus, Flavobacterium psychrophilum, Flavobacterium columnare, Aeromonas salmonicida, Yersinia ruckeri, Edwardsiella ictaluri, Renibacterium salmoninarum and Myxobolus cerebralis. To date, only the bacterial pathogens have been detected and prevalences have been low. Prevalences have varied each year and these changes are attributed to normal fluctuation of prevalence. All of the pathogens detected are widely distributed in Washington State.« less

Aerobic bacterial microbiota isolated from the cloaca of the European pond turtle (Emys orbicularis) in Poland.

PubMed

Nowakiewicz, Aneta; Ziółkowska, Grażyna; Zięba, Przemysław; Dziedzic, Barbara Majer; Gnat, Sebastian; Wójcik, Mariusz; Dziedzic, Roman; Kostruba, Anna

2015-01-01

We conducted a comparative analysis of the aerobic cloacal bacteria of European pond turtles (Emys orbicularis) living in their natural environment and juvenile turtles reared under controlled conditions in a breeding center. We included 130 turtles in the study. The aerobic bacteria isolated from the cloaca of the juvenile turtles were less diverse and more prevalent than the bacteria isolated from free-living adults. We isolated 17 bacterial species from juvenile captive turtles, among which the dominant species were Cellulomonas flavigena (77/96), Enterococcus faecalis (96/96), Escherichia coli (58/96), and Proteus mirabilis (41/96). From the adult, free-living turtles, we isolated 36 bacterial species, some of which are a potential threat to public health (e.g., Salmonella enterica serovars Newport, Daytona, and Braenderup; Listeria monocytogenes; Yersinia enterocolitica; Yersinia ruckeri; Klebsiella pneumoniae; Vibrio fluvialis; and Serratia marcescens), and pathogens that are etiologic agents of diseases of ectothermic animals (e.g., Aeromonas sobria, Aeromonas caviae, Hafnia alvei, Edwardsiella tarda, and Citrobacter braakii; the last two species were isolated from both groups of animals). The cloacal bacterial biota of the European pond turtle was characterized by numerous species of bacteria, and its composition varied with turtle age and environmental conditions. The small number of isolated bacteria that are potential human pathogens may indicate that the European pond turtle is of relatively minor importance as a threat to public health.

Comparative analysis of Edwardsiella tarda isolates from fish in the eastern United States suggests the existence of two genetically distinct species, Edwardsiella tarda and Edwardsiella pseudotarda sp. nov

USDA-ARS?s Scientific Manuscript database

Edwardsiella tarda, a Gram-negative member of the family Enterobacteriaceae, is often implicated in significant losses in aquaculture facilities worldwide. Here, we assessed the intra-specific variability of a collection of E. tarda isolates from 4 different fish species in the eastern United State...

Identification of Bacillus Strains for Biological Control of Catfish Pathogens

PubMed Central

Ran, Chao; Carrias, Abel; Williams, Malachi A.; Capps, Nancy; Dan, Bui C. T.; Newton, Joseph C.; Kloepper, Joseph W.; Ooi, Ei L.; Browdy, Craig L.; Terhune, Jeffery S.; Liles, Mark R.

2012-01-01

Bacillus strains isolated from soil or channel catfish intestine were screened for their antagonism against Edwardsiella ictaluri and Aeromonas hydrophila, the causative agents of enteric septicemia of catfish (ESC) and motile aeromonad septicaemia (MAS), respectively. Twenty one strains were selected and their antagonistic activity against other aquatic pathogens was also tested. Each of the top 21 strains expressed antagonistic activity against multiple aquatic bacterial pathogens including Edwardsiella tarda, Streptococcus iniae, Yersinia ruckeri, Flavobacterium columnare, and/or the oomycete Saprolegnia ferax. Survival of the 21 Bacillus strains in the intestine of catfish was determined as Bacillus CFU/g of intestinal tissue of catfish after feeding Bacillus spore-supplemented feed for seven days followed by normal feed for three days. Five Bacillus strains that showed good antimicrobial activity and intestinal survival were incorporated into feed in spore form at a dose of 8×107 CFU/g and fed to channel catfish for 14 days before they were challenged by E. ictaluri in replicate. Two Bacillus subtilis strains conferred significant benefit in reducing catfish mortality (P<0.05). A similar challenge experiment conducted in Vietnam with four of the five Bacillus strains also showed protective effects against E. ictaluri in striped catfish. Safety of the four strains exhibiting the strongest biological control in vivo was also investigated in terms of whether the strains contain plasmids or express resistance to clinically important antibiotics. The Bacillus strains identified from this study have good potential to mediate disease control as probiotic feed additives for catfish aquaculture. PMID:23029244

Edwardsiella andrillae, a new species of sea anemone from Antarctic ice.

PubMed

Daly, Marymegan; Rack, Frank; Zook, Robert

2013-01-01

Exploration of the lower surface of the Ross Ice Shelf in Antarctica by the Submersible Capable of under-Ice Navigation and Imaging (SCINI) remotely operated vehicle discovered a new species of sea anemone living in this previously undocumented ecosystem. This discovery was a significant outcome of the Coulman High Project's geophysical and environmental fieldwork in 2010-2011 as part of the ANDRILL (ANtarctic geologic DRILLing) program. Edwardsiella andrillae n. sp., lives with most of its column in the ice shelf, with only the tentacle crown extending into the seawater below. In addition to being the only Antarctic representative of the genus, Edwardsiella andrillae is distinguished from all other species of the genus in the number of tentacles and in the size and distribution of cnidae. The anatomy and histology of Edwardsiella andrillae present no features that explain how this animal withstands the challenges of life in such an unusual habitat.

Edwardsiella andrillae, a New Species of Sea Anemone from Antarctic Ice

PubMed Central

Daly, Marymegan; Rack, Frank; Zook, Robert

2013-01-01

Exploration of the lower surface of the Ross Ice Shelf in Antarctica by the Submersible Capable of under-Ice Navigation and Imaging (SCINI) remotely operated vehicle discovered a new species of sea anemone living in this previously undocumented ecosystem. This discovery was a significant outcome of the Coulman High Project’s geophysical and environmental fieldwork in 2010-2011 as part of the ANDRILL (ANtarctic geologic DRILLing) program. Edwardsiella andrillae n. sp., lives with most of its column in the ice shelf, with only the tentacle crown extending into the seawater below. In addition to being the only Antarctic representative of the genus, Edwardsiella andrillae is distinguished from all other species of the genus in the number of tentacles and in the size and distribution of cnidae. The anatomy and histology of Edwardsiella andrillae present no features that explain how this animal withstands the challenges of life in such an unusual habitat. PMID:24349517

Pathogen Screening of Naturally Produced Yakima River Spring Chinook Smolts; Yakima/Klickitat Fisheries Project Monitoring and Evaluation, 2002 Annual Report.

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

Thomas, Joan B.

2003-05-01

In 1999 the Cle Elem Hatchery began releasing spring chinook smolts into the upper Yakima River for restoration and supplementation. This project was designed to evaluate whether introduction of intensively reared hatchery produced smolts would impact the prevalence of specific pathogens in the naturally produced spring chinook smolts. Increases in prevalence of any of these pathogens could negatively impact the survival of these fish. Approximately 200 smolts were collected at the Chandler smolt collection facility on the lower Yakima River during 1998, 2000 and 2001 and 130 smolts were collected in 2002 for monitoring for specific pathogens. The pathogens monitoredmore » were infectious hematopoeitic necrosis virus, infectious pancreatic necrosis virus, viral hemorrhagic septicemia, Flavobacterium psychrophilum, Flavobacterium columnare, Aeromonas salmonicida, Yersinia ruckeri, Edwardsiella ictaluri, Renibacterium salmoninarum and Myxobolus cerebralis. In addition the fish were tested for Ceratomyxa shasta spores in 2000 and 2001 (a correction from the 2001 report). To date, the only changes have been in the levels the bacterial pathogens in the naturally produced smolts and they have been minimal. These changes are attributed to normal fluctuation of prevalence.« less

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

Homology analysis and cross-immunogenicity of OmpA from pathogenic Yersinia enterocolitica, Yersinia pseudotuberculosis and Yersinia pestis.

PubMed

Chen, Yuhuang; Duan, Ran; Li, Xu; Li, Kewei; Liang, Junrong; Liu, Chang; Qiu, Haiyan; Xiao, Yuchun; Jing, Huaiqi; Wang, Xin

2015-12-01

The outer membrane protein A (OmpA) is one of the intra-species conserved proteins with immunogenicity widely found in the family of Enterobacteriaceae. Here we first confirmed OmpA is conserved in the three pathogenic Yersinia: Yersinia pestis, Yersinia pseudotuberculosis and pathogenic Yersinia enterocolitica, with high homology at the nucleotide level and at the amino acid sequence level. The identity of ompA sequences for 262 Y. pestis strains, 134 Y. pseudotuberculosis strains and 219 pathogenic Y. enterocolitica strains are 100%, 98.8% and 97.7% similar. The main pattern of OmpA of pathogenic Yersinia are 86.2% and 88.8% identical at the nucleotide and amino acid sequence levels, respectively. Immunological analysis showed the immunogenicity of each OmpA and cross-immunogenicity of OmpA for pathogenic Yersinia where OmpA may be a vaccine candidate for Y. pestis and other pathogenic Yersinia. Copyright © 2015 Elsevier Ltd. All rights reserved.

Complete genome sequence of Edwardsiella hoshinae ATCC 35051

USDA-ARS?s Scientific Manuscript database

Edwardsiella hoshinae is a Gram-negative, facultative anaerobe that has been primarily isolated from avians and reptiles. We report here the complete and annotated genome of an isolate from a monitor lizard (Varanus sp.), which contains a chromosome of 3,811,650 bp and no plasmids....

Pathogen Screening of Naturally Produced Yakima River Spring Chinook Smolts; Yakima/Klickitat Fisheries Project Monitoring and Evaluation, 2001 Annual Report.

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

Pearsons, Todd N.; Thomas, Joan B.

2003-01-01

The change in pathogens prevalence to wild fish is probably the least studied ecological interaction associated with hatchery operations. In 1999, the Cle Elum Hatchery began releasing spring chinook smolts into the upper Yakima River to increase natural production. Part of the evaluation of this program is to evaluate whether introduction of hatchery produced smolts would impact the prevalence of specific pathogens in the naturally produced spring chinook smolts. Increases in prevalence of any of these pathogens could negatively impact the survival of these fish. Approximately 200 smolts were collected at the Chandler smolt collection facility on the lower Yakimamore » River during 1998, 2000 and 2001 and monitored for specific pathogens. The pathogens monitored were infectious hematopoeitic necrosis virus, infectious pancreatic necrosis virus, viral hemorrhagic septicemia, Flavobacterium psychrophilum, Flavobacterium columnare, Aeromonas salmonicida, Yersinia ruckeri, Edwardsiella ictaluri, Renibacterium salmoninarum and Myxobolus cerebralis. In addition, the fish were tested for Ceratomyxa shasta spores in 2001. Not all testing has been completed for every year, but to date, there have only been minimal changes in levels of the bacterial pathogens in the naturally produced smolts. At this point, due to the limited testing so far, these changes are attributed to normal fluctuation of prevalence.« less

Towards the intelligent design of a vaccine against Edwardsiella ictaluri

USDA-ARS?s Scientific Manuscript database

Edwardsiella ictaluri is the leading cause of disease loss in the catfish industry in the United States, accounting for an estimated 20.2 % loss in 2009. Previous work to establish live-attenuated vaccines for E. ictaluri demonstrated a relatively weak channel catfish immune response, with better im...

Organization and sequence of four flagellin-encoding genes of Edwardsiella icataluri

USDA-ARS?s Scientific Manuscript database

Edwardsiella ictaluri, the cause of enteric septicemia in channel catfish (Ictalurus punctatus), is motile by means of peritrichous flagella. We determined the complete flagellin gene sequences and their organization in E. ictaluri by sequencing genomic segments selected from a lambda-ZAP phage gen...

First report of the occurrence and whole-genome characterization of Edwardsiella tarda in the false killer whale (Pseudorca crassidens).

PubMed

Lee, Kyunglee; Kim, Hye Kwon; Park, Sung-Kyun; Sohn, Hawsun; Cho, Yuna; Choi, Young-Min; Jeong, Dae Gwin; Kim, Ji Hyung

2018-04-25

Although several Edwardsiella tarda infections have been reported, its pathogenic role in marine mammals has not been investigated at the genome level. We investigated the genome of E. tarda strain KC-Pc-HB1, isolated from the false killer whale (Pseudorca crassidens) found bycaught in South Korea. The obtained genome was similar to that of human pathogenic E. tarda strains, but distinct from other Edwardsiella species. Although type III and VI secretion systems, which are essential for the virulence of other Edwardsiella species, were absent, several virulence-related genes involved in the pathogenesis of E. tarda were found in the genome. These results provide important insights into the E. tarda infecting marine mammals and give valuable information on potential virulence factors in this pathogen.

Pathogen Screening of Naturally Produced Yakima River Spring Chinook Smolts; Yakima/Klickitat Fisheries Project Monitoring and Evaluation, 2004-2005 Annual Report.

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

Thomas, Joan B.

2005-05-01

In the spring of 2004 naturally produced smolts outmigrating from the Yakima River Basin were collected for the sixth year of pathogen screening. This component of the evaluation is to monitor whether introduction of hatchery produced smolts would impact the prevalence of specific pathogens in the naturally produced spring chinook smolts. Increases in prevalence of any of these pathogens could negatively impact the survival of these fish. Since 1999 the Cle Elum Hatchery has been releasing spring chinook salmon smolts into the upper Yakima River to increase natural production. In 1998 and 2000 through 2004 naturally produced smolts were collectedmore » for monitoring at the Chandler smolt collection facility on the lower Yakima River. Smolts were collected from mid to late outmigration, with a target of 200 fish each year. The pathogens monitored were infectious hematopoeitic necrosis virus, infectious pancreatic necrosis virus, viral hemorrhagic septicemia virus, Flavobacterium psychrophilum, Flavobacterium columnare, Aeromonas salmonicida, Yersinia ruckeri, Edwardsiella ictaluri, Renibacterium salmoninarum and Myxobolus cerebralis. Of these pathogens, only R. salmoninarum was detected in very low levels in the naturally produced smolts outmigrating in 2004. To date, only bacterial pathogens have been detected and prevalences have been low. There have been small variations each year and these changes are attributed to normal fluctuations in prevalence. All of the pathogens detected are widely distributed in Washington State.« less

Modified live Edwardsiella ictaluri vaccine, AQUAVAC-ESC, lacks multidrug resistance plasmids

USDA-ARS?s Scientific Manuscript database

Plasmid mediated antibiotic resistance was first discovered in Edwardsiella ictaluri in the early 1990’s, and in 2007 an E. ictaluri isolate harboring an IncA/C plasmid was recovered from a moribund channel catfish infected with the bacterium. Due to the identification of multidrug resistance plasm...

Transferable green fluorescence-tagged pEI2 in Edwardsiella ictaluri

USDA-ARS?s Scientific Manuscript database

The pEI2 plasmid of Edwardsiella ictaluri isolate, I49, was tagged using a Tn10-GFP-kan cassette to create the green fluorescence-expressing derivative I49-gfp. The Tn10-GFP-kan insertion site was mapped by plasmid sequencing to 663 bp upstream of orf2 and appeared to be at a neutral site in the pla...

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)).

Pathogens associated with native and exotic trout populations in Shenandoah National Park and the relationships to fish stocking practices

USGS Publications Warehouse

Panek, Frank M.; Atkinson, James; Coll, John

2008-01-01

Restrictive fish stocking policies in National Parks were developed as early as 1936 in order to preserve native fish assemblages and historic genetic diversity. Despite recent efforts to understand the effects of non-native or exotic fish introductions, park managers have limited information regarding the effects of these introductions on native fish communities. Shenandoah National Park was established in 1936 and brook trout (Salvelinus fontinalis) restoration within selected streams in the park began in 1937 in collaboration with the Virginia Department of Game and Inland Fisheries (VDGIF). An analysis of tissue samples from brook, brown (Salmo trutta), and rainbow trout (Oncorhynchus mykiss) from 29 streams within the park from 1998–2002 revealed the presence of Renibacterium salmoninarum, Yersinia ruckeri, and infectious pancreatic necrosis virus (IPNv). In order to investigate the relationships of the occurrence of fish pathogens with stocking histories we classified the streams into three categories: 1) streams with no record of stocking, 2) streams that are known to have been stocked historically, and 3) streams that were historically stocked within the park and continue to be stocked downstream of the park boundary. The occurrences of pathogens were summarized relative to this stocking history. Renibacterium salmoninarum, the causative agent of bacterial kidney disease, was the most prevalent pathogen found, occurring in all three species and stream stocking categories, and appears to be endemic to the park. Two other pathogens, Yersinia ruckeri and infectious pancreatic necrosis virus were also described from brook trout populations within the park. IPNv was only found in brook trout populations in streams with prior stocking histories. Yersinia ruckeri was only found in brook trout in steams that have never been stocked and like R. salmoninarum, is likely endemic.

Complete genome sequence of multidrug-resistant Edwardsiella ictaluri strain MS-17-156

USDA-ARS?s Scientific Manuscript database

Edwardsiella ictaluri is a Gram-negative bacillus in the order Enterobacteriales. It is the etiologic agent of enteric septicemia of catfish (ESC), one of the most significant diseases of the commercial catfish industry in the United States. E. ictaluri strain MS-17-156 was isolated from a diseased...

Denaturing gradient gel electrophoresis for nonlethal detection of Aeromonas salmonicida in salmonid mucus and its potential for other bacterial fish pathogens.

PubMed

Quinn, Robert A; Stevenson, Roselynn M W

2012-05-01

Denaturing gradient gel electrophoresis (DGGE) of 16S rDNA was used to nonlethally detect Aeromonas salmonicida and other bacteria in salmonid skin mucus. Mucus samples from wild spawning coho salmon (Oncorhynchus kisutch) with endemic A. salmonicida and from cultured lake trout (Salvelinus namaycush) were tested by PCR-DGGE and were compared with mucus culture on Coomassie brilliant blue agar and internal organ culture. PCR-DGGE gave a highly reproducible 4-band pattern for 9 strains of typical A. salmonicida, which was different from other Aeromonas spp. Aeromonas salmonicida presence in mucus was evident as a band that comigrated with the bottom band of the A. salmonicida 4-band pattern and was verified by sequencing. PCR-DGGE found 36 of 52 coho salmon positive for A. salmonicida, compared with 31 positive by mucus culture and 16 by organ culture. Numerous other bacteria were detected in salmonid mucus, including Pseudomonas spp., Shewanella putrefaciens, Aeromonas hydrophila and other aeromonads. However, Yersinia ruckeri was not detected in mucus from 27 lake trout, but 1 fish had a sorbitol-positive Y. ruckeri isolated from organ culture. Yersinia ruckeri seeded into a mucus sample suggested that PCR-DGGE detection of this bacterium from mucus was possible. PCR-DGGE allows nonlethal detection of A. salmonicida in mucus and differentiation of some Aeromonas spp. and has the potential to allow simultaneous detection of other pathogens present in fish mucus.

Edwardsiellosis Caused by Edwardsiella ictaluri in Laboratory Populations of Zebrafish Danio rerio

PubMed Central

Hawke, John P.; Kent, Michael; Rogge, Matt; Baumgartner, Wes; Wiles, Judy; Shelley, Johnny; Savolainen, L. Christine; Wagner, Robert; Murray, Katy; Peterson, Tracy S.

2014-01-01

We report the first cases of Edwardsiella ictaluri causing epizootics in laboratory populations of Zebrafish Danio rerio. Edwardsiella ictaluri is primarily recognized as a disease of catfish species and is known to cause an economically important bacterial disease of farm-raised catfish in the USA and abroad; however, it has been isolated on occasion from 10 other genera of nonictalurid fishes. We isolated E. ictaluri from moribund Zebrafish held in quarantine at two different universities in two states and from a research facility in a third state between February 23 and December 6, 2011. Edwardsiellosis in Zebrafish can be described as a severe systemic disease characterized by tissue necrosis and the presence of large numbers of extracellular and intracellular bacteria, often within macrophages. The kidneys (pronephros and mesonephros), spleen, nares, and forebrain were the most commonly and severely affected tissues. In outbreaks, mortality was acute and numerous fish died over a 1–2 week period. Mortality continued until the majority of the population was lost, at which time the remaining fish were euthanized. In addition to these cases, four cultures of bacteria isolated from Zebrafish by another diagnostic laboratory were submitted to the Louisiana Aquatic Diagnostic Laboratory for identification and were confirmed as E. ictaluri. In total, eight cultures of E. ictaluri from Zebrafish from Louisiana, Massachusetts, Pennsylvania, and Florida were identified. The isolates were confirmed as E. ictaluri by biochemical phenotype, API 20E (bioMérieux), and amplification and sequencing of a portion of the 16S rRNA gene. Edwardsiella ictaluri isolates from Zebrafish are believed to comprise a unique group and were differentiated from catfish isolates by exhibiting weaker motility, autoaggregation in broth, a different plasmid profile (two plasmids of 4.0 and 3.5 kb), a different API 20E code (4204000), and lack of lipopolysaccharide recognition with Mab Ed9

Complete genome sequence of Edwardsiella tarda (isolate FL95-01)recovered from channel catfish

USDA-ARS?s Scientific Manuscript database

Edwardsiella tarda is a Gram-negative facultative anaerobe isolated from fish, reptiles, amphibians, and mammals, including humans. This is a report of the complete and annotated genome of E. tarda isolate FL95-01, recovered from channel catfish (Ictalurus punctatus)....

Global gene expression in channel catfish after vaccination with an attenuated Edwardsiella ictaluri

USDA-ARS?s Scientific Manuscript database

To understand the global gene expression in channel catfish after immersion vaccination with an attenuated Edwardsiella ictaluri (AquaVac ESCTM), microarray analysis of 65,182 UniGene transcripts were performed. With a filter of false-discovery rate less than 0.05 and fold change greater than 2, a t...

Efficacy of a live attenuated Edwardsiella ictaluri oral vaccine in channel and hybrid catfish

USDA-ARS?s Scientific Manuscript database

Intensive fish production systems resort to higher stocking densities and feeding rates in culture conditions to manifest suboptimal conditions to facilitate disease outbreaks leading to production losses. This study was conducted to evaluate the efficacy of an oral live-attenuated Edwardsiella ict...

Oral vaccination with LcrV from Yersinia pestis KIM delivered by live attenuated Salmonella enterica serovar Typhimurium elicits a protective immune response against challenge with Yersinia pseudotuberculosis and Yersinia enterocolitica.

PubMed

Branger, Christine G; Torres-Escobar, Ascención; Sun, Wei; Perry, Robert; Fetherston, Jacqueline; Roland, Kenneth L; Curtiss, Roy

2009-08-27

The use of live recombinant attenuated Salmonella vaccines (RASV) synthesizing Yersinia proteins is a promising approach for controlling infection by Yersinia species. In this study, we constructed attenuated Salmonella strains which synthesize a truncated form of LcrV, LcrV196 and evaluated the immune response and protective efficacy elicited by these strains in mice against two other major species of Yersinia: Yersinia pseudotuberculosis and Yersinia enterocolitica. Surprisingly, we found that the RASV strain alone was sufficient to afford nearly full protection against challenge with Y. pseudotuberculosis, indicating the likelihood that Salmonella produces immunogenic cross-protective antigens. In contrast, lcrV196 expression was required for protection against challenge with Y. enterocolitica strain 8081, but was not sufficient to achieve significant protection against challenge with Y. enterocolitica strain WA, which expressed a divergent form of lcrV. Nevertheless, we are encouraged by these findings to continue pursuing our long-term goal of developing a single vaccine to protect against all three human pathogenic species of Yersinia.

Efficacy of a live attenuated Edwardsiella ictaluri oral vaccine in channel and hybrid catfish

USDA-ARS?s Scientific Manuscript database

This study evaluated the efficacy of an oral live-attenuated Edwardsiella ictaluri vaccine against enteric septicemia of catfish (ESC) in channel and hybrid catfish. The vaccine was delivered orally by feeding fish a diet coated with an attenuated E. ictaluri isolate at four doses to deliver betwee...

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.

Comparative phenotypic and genotypic analysis of Edwardsiella spp. isolates from different hosts and geographic origins, with an emphasis on isolates formerly classified as E. tarda and an evaluation of diagnostic methods

USDA-ARS?s Scientific Manuscript database

Aims: Conventional phenotypic and genotypic analyses for the differentiation of phenotypically ambiguous Edwardsiella congeners was evaluated and historical E. tarda designations were linked to current taxonomic nomenclature. Methods and Results: Forty-seven Edwardsiella spp. isolates recovered over...

Efficacy of florfenicol for control of mortality associated with Edwardsiella ictaluri in three species of catfish

USDA-ARS?s Scientific Manuscript database

The efficacy of florfenicol against Edwardsiella icatluri infection was studied in channel catfish (Ictalurus puntatus (Delta strain)), hybrid catfish (Ictalurus punctatus (Delta strain) x Ictalurus furcatus (D&B strain)), and blue catfish (Ictalurus furcatus (D&B strain) fingerlings in 65L aquaria....

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.

Oral vaccination of channel catfish against enteric septicemia of catfish using a live attenuated Edwardsiella ictaluri isolate

USDA-ARS?s Scientific Manuscript database

Enteric septicemia of catfish (ESC), caused by Edwardsiella ictaluri, is the most problematic bacterial disease affecting catfish aquaculture in the southeastern United States. Efforts to develop an effective ESC vaccine have had limited industrial success. In commercial settings, ESC vaccines are...

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.

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

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.

Oral vaccination of channel catfish against enteric septicemia of catfish (ESC) using a live attenuated Edwardsiella ictaluri isolate

USDA-ARS?s Scientific Manuscript database

Enteric septicemia of catfish (ESC), caused by Edwardsiella ictaluri, is the most problematic bacterial disease affecting catfish aquaculture in the southeastern United States. Efforts to develop an effective ESC vaccine have had limited industrial success. In commercial settings, ESC vaccines are t...

Ichthyophthirius multifiliis as a potential vector of Edwardsiella ictaluri in channel catfish.

PubMed

Xu, De-Hai; Shoemaker, Craig A; Klesius, Phillip H

2012-04-01

There is limited information on whether parasites act as vectors to transmit bacteria in fish. In this trial, we used Ichthyophthirius multifiliis and fluorescent Edwardsiella ictaluri as a model to study the interaction between parasite, bacterium, and fish. The percentage (23-39%) of theronts fluorescing after exposure to E. ictaluri was significantly higher than control theronts (~ 6%) using flow cytometry. Theronts exposed to E. ictaluri at 4 × 10(7)  CFU mL(-1) showed a higher percentage (~ 60%) of fluorescent theronts compared to those (42%) exposed to 4 × 10(3)  CFU mL(-1) at 4 h. All tomonts (100%) carried the bacterium after exposure to E. ictaluri. Edwardsiella ictaluri survived and replicated during tomont division. Confocal microscopy demonstrated that E. ictaluri was associated with the tomont surface. Among theronts released from tomonts exposed to E. ictaluri, 31-66% were observed with attached E. ictaluri. Sixty percent of fish exposed to theronts treated with 5 × 10(7) E. ictaluri mL(-1) were positive for E. ictaluri at 4 h as determined by qPCR or fluorescent microscopy. Fluorescent E. ictaluri were observed on trophonts in skin and gill wet mounts of dead fish. This study demonstrated that Ich could vector E. ictaluri to channel catfish. © 2012 Federation of European Microbiological Societies. Published by Blackwell Publishing 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.

Production of a reference transcriptome and transcriptomic database (EdwardsiellaBase) for the lined sea anemone, Edwardsiella lineata, a parasitic cnidarian

PubMed Central

2014-01-01

Background The lined sea anemone Edwardsiella lineata is an informative model system for evolutionary-developmental studies of parasitism. In this species, it is possible to compare alternate developmental pathways leading from a larva to either a free-living polyp or a vermiform parasite that inhabits the mesoglea of a ctenophore host. Additionally, E. lineata is confamilial with the model cnidarian Nematostella vectensis, providing an opportunity for comparative genomic, molecular and organismal studies. Description We generated a reference transcriptome for E. lineata via high-throughput sequencing of RNA isolated from five developmental stages (parasite; parasite-to-larva transition; larva; larva-to-adult transition; adult). The transcriptome comprises 90,440 contigs assembled from >15 billion nucleotides of DNA sequence. Using a molecular clock approach, we estimated the divergence between E. lineata and N. vectensis at 215–364 million years ago. Based on gene ontology and metabolic pathway analyses and gene family surveys (bHLH-PAS, deiodinases, Fox genes, LIM homeodomains, minicollagens, nuclear receptors, Sox genes, and Wnts), the transcriptome of E. lineata is comparable in depth and completeness to N. vectensis. Analyses of protein motifs and revealed extensive conservation between the proteins of these two edwardsiid anemones, although we show the NF-κB protein of E. lineata reflects the ancestral structure, while the NF-κB protein of N. vectensis has undergone a split that separates the DNA-binding domain from the inhibitory domain. All contigs have been deposited in a public database (EdwardsiellaBase), where they may be searched according to contig ID, gene ontology, protein family motif (Pfam), enzyme commission number, and BLAST. The alignment of the raw reads to the contigs can also be visualized via JBrowse. Conclusions The transcriptomic data and database described here provide a platform for studying the evolutionary developmental genomics

Production of a reference transcriptome and transcriptomic database (EdwardsiellaBase) for the lined sea anemone, Edwardsiella lineata, a parasitic cnidarian.

PubMed

Stefanik, Derek J; Lubinski, Tristan J; Granger, Brian R; Byrd, Allyson L; Reitzel, Adam M; DeFilippo, Lukas; Lorenc, Allison; Finnerty, John R

2014-01-28

The lined sea anemone Edwardsiella lineata is an informative model system for evolutionary-developmental studies of parasitism. In this species, it is possible to compare alternate developmental pathways leading from a larva to either a free-living polyp or a vermiform parasite that inhabits the mesoglea of a ctenophore host. Additionally, E. lineata is confamilial with the model cnidarian Nematostella vectensis, providing an opportunity for comparative genomic, molecular and organismal studies. We generated a reference transcriptome for E. lineata via high-throughput sequencing of RNA isolated from five developmental stages (parasite; parasite-to-larva transition; larva; larva-to-adult transition; adult). The transcriptome comprises 90,440 contigs assembled from >15 billion nucleotides of DNA sequence. Using a molecular clock approach, we estimated the divergence between E. lineata and N. vectensis at 215-364 million years ago. Based on gene ontology and metabolic pathway analyses and gene family surveys (bHLH-PAS, deiodinases, Fox genes, LIM homeodomains, minicollagens, nuclear receptors, Sox genes, and Wnts), the transcriptome of E. lineata is comparable in depth and completeness to N. vectensis. Analyses of protein motifs and revealed extensive conservation between the proteins of these two edwardsiid anemones, although we show the NF-κB protein of E. lineata reflects the ancestral structure, while the NF-κB protein of N. vectensis has undergone a split that separates the DNA-binding domain from the inhibitory domain. All contigs have been deposited in a public database (EdwardsiellaBase), where they may be searched according to contig ID, gene ontology, protein family motif (Pfam), enzyme commission number, and BLAST. The alignment of the raw reads to the contigs can also be visualized via JBrowse. The transcriptomic data and database described here provide a platform for studying the evolutionary developmental genomics of a derived parasitic life cycle. In

Comparative genomic analysis of bacteriophages specific to the channel catfish pathogen Edwardsiella ictaluri

PubMed Central

2011-01-01

Background The bacterial pathogen Edwardsiella ictaluri is a primary cause of mortality in channel catfish raised commercially in aquaculture farms. Additional treatment and diagnostic regimes are needed for this enteric pathogen, motivating the discovery and characterization of bacteriophages specific to E. ictaluri. Results The genomes of three Edwardsiella ictaluri-specific bacteriophages isolated from geographically distant aquaculture ponds, at different times, were sequenced and analyzed. The genomes for phages eiAU, eiDWF, and eiMSLS are 42.80 kbp, 42.12 kbp, and 42.69 kbp, respectively, and are greater than 95% identical to each other at the nucleotide level. Nucleotide differences were mostly observed in non-coding regions and in structural proteins, with significant variability in the sequences of putative tail fiber proteins. The genome organization of these phages exhibit a pattern shared by other Siphoviridae. Conclusions These E. ictaluri-specific phage genomes reveal considerable conservation of genomic architecture and sequence identity, even with considerable temporal and spatial divergence in their isolation. Their genomic homogeneity is similarly observed among E. ictaluri bacterial isolates. The genomic analysis of these phages supports the conclusion that these are virulent phages, lacking the capacity for lysogeny or expression of virulence genes. This study contributes to our knowledge of phage genomic diversity and facilitates studies on the diagnostic and therapeutic applications of these phages. PMID:21214923

Septicaemia caused by Edwardsiella tarda and Plesiomonas shigelloides in captive penguin chicks.

PubMed

Nimmervoll, H; Wenker, C; Robert, N; Albini, S

2011-03-01

Three cases of fatal septicaemia due to Plesiomonas shigelloides and one due to Edwardsiella tarda were diagnosed in newborn penguins from the Basle Zoo, Switzerland from 2003 to 2007. The affected penguins were of two different species (king penguin, Aptenodytes patagonicus, and African penguin, Spheniscus demersus) and between 2 and 10 days old at the time of death. The causative agents, E. tarda and P. shigelloides are ubiquitous bacteria which are reported to be present in the normal intestinal flora of wild and captive aquatic animals, including penguins. Their occurrence and infectious potential is discussed.

Detection of Yersinia enterocolitica in Retail Chicken Meat, Mashhad, Iran.

PubMed

Sirghani, Khadigeh; Zeinali, Tayebeh; Jamshidi, Abdollah

2018-01-01

Poultry meat is one of the most important sources of infection of Yersinia spp. for humans. The aim of the present study was to evaluate the incidence of Yersinia enterocolitica in chicken meat by using culture method on selective medium and confirmation by PCR assay. Also, biochemical methods were used for biotyping. A total of 100 chicken thigh meat samples were collected randomly from retail outlets in Mashhad, Iran. Samples were enriched in Peptone-Sorbitol-Bile (PSB) broth and then cultured on Cefsulodin-Irgasan-Novobiocin (CIN) agar containing antibiotics supplement. The DNA was extracted from suspected colonies of Yersinia spp. and then PCR test using specific primers for 16S rRNA gene of Yersinia enterocolitica was performed. In this study, 30% of chicken meat was contaminated with Yersinia spp. by culture method and 25% of chicken meat was contaminated with Yersinia enterocolitica . Biotyping of isolated colonies showed that all of the isolates belonged to biotype 1A. Culture and detection of Yersinia spp. from food samples traditionally take 4 days. Due to high accuracy and speed of PCR assay, it is a good alternative method for microbiological techniques. In conclusion, poultry meat can act as a source of Y. enterocolitica and could be considered as a public health hazard.

Analysis of 16S-23S intergenic spacer regions of the rRNA operons in Edwardsiella ictaluri and Edwardsiella tarda isolates from fish.

PubMed

Panangala, V S; van Santen, V L; Shoemaker, C A; Klesius, P H

2005-01-01

To analyse interspecies and intraspecies differences based on the 16S-23S rRNA intergenic spacer region (ISR) sequences of the fish pathogens Edwardsiella ictaluri and Edwardsiella tarda. The 16S-23S rRNA spacer regions of 19 Edw. ictaluri and four Edw. tarda isolates from four geographical regions were amplified by PCR with primers complementary to conserved sequences within the flanking 16S-23S rRNA coding sequences. Two products were generated from all isolates, without interspecies or intraspecific size polymorphisms. Sequence analysis of the amplified fragments revealed a smaller ISR of 350 bp, which contained a gene for tRNA(Glu), and a larger ISR of 441 bp, which contained genes for tRNA(Ile) and tRNA(Ala). The sequences of the smaller ISR of different Edw. ictaluri isolates were essentially identical to each other. Partial sequences of larger ISR from several Edw. ictaluri isolates also revealed no differences from the one complete Edw. ictaluri large ISR sequence obtained. The sequences of the smaller ISR of Edw. tarda were 97% identical to the Edw. ictaluri smaller ISR and the larger ISR were 96-98% identical to the Edw. ictaluri larger ISR sequence. The Edw. tarda isolates displayed limited ISR sequence heterogeneity, with > or =97% sequence identity among isolates for both small and large ISR. There is a high degree of size and sequence similarity of 16S-23S ISR both among isolates within Edw. ictaluri and Edw. tarda species and between the two species. Our results confirm a close genetic relationship between Edw. ictaluri and Edw. tarda and the relative homogeneity of Edw. ictaluri isolates compared with Edw. tarda isolates. Because no differences were found in ISR sequences among Edw. ictaluri isolates, sequence analysis of the ISR will not be useful to distinguish isolates of Edw. ictaluri. However, we identified restriction sites that differ between ISR sequences of Edw. ictaluri and Edw. tarda, which will be useful in distinguishing the two species.

[Occurrence of bacteria of the Yersinia genus in surface water].

PubMed

Krogulska, B; Maleszewska, J

1992-01-01

The aim of the study was determination of the frequency of occurrence of Yersinia genus bacteria in surface waters polluted to various degrees with bacteria of the coliform and of fecal coli. For detection of Yersinia rods the previously elaborated medium Endo MLCe and the membrane filter method were applied. Samples of 42 surface waters were examined, including 26 from rivers and 16 from lakes, ponds and clay-pits. On the basis of sanitary bacteriological analysis 16 surface waters were classified to class I purity, 10 to class II, the remaining ones to class III or beyond classification. Yersinia rods were detected in 15 water bodies that is 35.7% of the examined waters. A total of 27 Yersinia strains were identified with dominance of Y. intermedia (14 strains) and Y. enterocolitica (10 strains). Three strains represented by the species Yersinia frederiksenii. Most of the Y. enterocolitica strains belonged to biotype 1, the particular strains being represented by various serotypes. Hence their different origin may be concluded. The pathogenic serotypes 0:3 and 0:9 of Yersinia enterocolitica were not detected.

Edwardsiella ictaluri Encodes an Acid Activated Urease that is Required for Intracellular Replication in Channel Catfish Ictalurus punctatus Macrophages

USDA-ARS?s Scientific Manuscript database

Genomic analysis indicated that Edwardsiella ictaluri encodes a putative ureasepathogenicity island containing 9 open reading frames, including urea and ammonium transporters. In vitro studies with the wild-type E. ictaluri and a ureG::kan urease mutant strain indicated that E. ictaluri is significa...

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

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 .

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.

Complete genome sequence of Edwardsiella ictaluri isolate RUSVM-1 recovered from nile tilapia (Oreochromis niloticus) in the Western Hemisphere

USDA-ARS?s Scientific Manuscript database

Edwardsiella ictaluri is a Gram-negative, bacillus that has recently been implicated in disease outbreaks in tilapia and zebrafish. We report here the complete and annotated genome of an isolate from a Nile Tilapia (Oreochromis niloticus), which contains a chromosome of 3,630,639 bp and two plasmids...

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

Emergence of Edwardsiella piscicida in farmed channel femal, Ictalurus punctatus X blue male, Ictalurus furcatus, hybrid catfish cultured in Mississippi

USDA-ARS?s Scientific Manuscript database

here is a trend toward the increased incidence and prevalence of Edwardsiella piscicida septicemia in US catfish aquaculture, particularly in channel ', Ictalurus punctatus, × blue ', I. furcatus, hybrid catfish. From 2013 to 2017, a total of 3242 disease case submissions were made to the Aquatic Re...

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.

Effects of a phytogenic feed additive on susceptibility of channel catfish to Edwardsiella ictaluri and levels of rhamnose binding lectin

USDA-ARS?s Scientific Manuscript database

We investigated the effects of a phytogenic feed additive (Digestarom® P.E.P. MGE) on growth performance, disease susceptibility to Edwardsiella ictaluri, and regulation of six rhamnose binding lectin (RBL) genes. Two hundred and fifty juvenile channel catfish (13.4 ± 0.1 g) were allotted to the fo...

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

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.

'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.

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.

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.

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.

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

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.

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.

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.

Influence of Edwardsiella ictaluri Septicemia on nitrite-induced methemoglobinemia in channel catfish (Ictalurus punctatus)

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

Tucker, C.S.; MacMillan, J.R.; Schwedler, T.E.

1984-06-01

In a previous report, the authors showed that lack of acclimation to nitrite can result in abnormally high levels of methemoglobin in nitrite-exposed channel catfish. They also observed abnormal methemoglobin levels in fish when concurrent bacteremias are present. Enteric Septicemia of Catfish is an acute bacterial disease caused by Edwardsiella ictaluri. Nitrite-induced methemoglobinemia and Enteric Septicemia of Catfish are both economically important diseases of commercially cultured channel catfish. In the present study, the authors investigated the influence of acute infection with E. ictaluri on the level of methemoblobin in nitrite-exposed channel catfish fingerlings.

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.

Immunomodulation and disease resistance in postyearling rainbow trout infected with Myxobolus cerebralis, the causative agent of whirling disease

USGS Publications Warehouse

Densmore, Christine L.; Ottinger, C.A.; Blazer, V.S.; Iwanowicz, L.R.; Smith, D.R.

2004-01-01

Myxobolus cerebralis, the myxosporean parasite that causes whirling disease, has a number of deleterious effects on its salmonid host. Although it is well established that juvenile salmonids in the active stages of whirling disease mount an immune response to the pathogen, the occurrence and longevity of any related immunomodulatory effects are unknown. In this study, postyearling rainbow trout Oncorhynchus mykiss infected with M. cerebralis were examined for leukocyte functions and for resistance to Yersinia ruckeri, a bacterial pathogen of salmonids. Compared with uninfected controls, M. cerebralis-infected fish showed lower proliferative lymphocyte responses to four mitogens (concanavalin A, pokeweed mitogen, phytohemagglutinin, and lipopolysaccharide). Conversely, M. cerebralis-infected fish displayed greater bactericidal activity of anterior kidney macrophages than did uninfected fish. After bath challenges with K. ruckeri, M. cerebralis-infected fish had slightly lower survival and a more rapid onset of mortality than did the control fish. Renal tissue and fecal samples from M. cerebralis-infected and uninfected survivors were cultured for the presence of K. ruckeri, and no difference in prevalence was noted between the two groups. Because immunomodulatory changes in the M. cerebralis-infected fish involved functional enhancement and suppression of different leukocyte populations, disease resistance among M. cerebralis-infected fish in the later stages of whirling disease will probably vary with the secondary pathogen and the nature of immune response the pathogen evokes.

Spleen size and plasma levels of mannose binding lectin in channel catfish Ictalurus punctatus families exhibiting different susceptibilities to Flavobacterium columnare and Edwardsiella ictaluri

USDA-ARS?s Scientific Manuscript database

Two major problems in the channel catfish (Ictalurus punctatus) aquaculture industry have been high disease losses to enteric septicemia of catfish (ESC), caused by the bacterium Edwardsiella ictaluri and columnaris disease, caused by the bacterium Flavobacterium columnare. Methods to control these...

Bactericidal efficacy of elevated pH on fish pathogenic and environmental bacteria

USGS Publications Warehouse

Starliper, Clifford E.; Watten, Barnaby J.

2013-01-01

Ship ballast water is a recognized medium for transfer and introductions of nonindigenous species. There is a need for new ballast water treatment methods that effectively and safely eliminate or greatly minimize movements of these species. The present study employed laboratory methods to evaluate the bactericidal efficacy of increased pH (pH 10.0–12.0) for exposure durations of up to 72 h to kill a variety of Gram-negative and Gram-positive bacteria including fish pathogens (Aeromonas spp., Yersinia ruckeri, Edwardsiella ictaluri, Serratia liquefaciens, Carnobacterium sp.), other common aquatic-inhabitant bacteria (Serratia marcescens, Pseudomonas fluorescens, Staphylococcus sp., Bacillus sp.) and indicators listed in International Maritime Organization D2 Standards; namely, Vibrio cholera (an environmental isolate from fish), Escherichia coli and Enterococcus faecalis. Volumes of 5 N NaOH were added to tryptic soy broth to obtain desired pH adjustments. Viable cells were determined after 0, 4, 12, 24, 48, and 72 h. Initial (0 h) cell numbers ranged from 3.40 × 104 cfu/mL for Bacillus sp. to 2.44 × 107 cfu/mL for E. faecalis. The effective endpoints of pH and treatment duration necessary to realize 100% bactericidal effect varied; however, all bacteria tested were killed within 72 h at pH 12.0 or lower. The lowest parameters examined, 4 h at pH 10.0, were bactericidal to V. cholera, E. ictaluri, three of four isolates of E. coli, and (three of four) Aeromonas salmonicida subsp. salmonicida. Bactericidal effect was attained at pH 10.0 within 12 h for the other A. salmonicida subsp. salmonicida, and within 24 h for P. fluorescens, and the remaining E. coli.

Systemic Edwardsiella tarda infection in a Western African lungfish (Protopterus annectens) with cytologic observation of heterophil projections.

PubMed

Rousselet, Estelle; Stacy, Nicole I; Rotstein, David S; Waltzek, Tom B; Griffin, Matt J; Francis-Floyd, Ruth

2018-06-08

This report describes a case of systemic bacterial infection caused by Edwardsiella tarda in a Western African lungfish (Protopterus annectens) exposed to poor environmental and husbandry conditions. The fish presented with a large, external ulcerative lesion and died 2 weeks after developing anorexia. Histological evaluation revealed multifocal areas of necrosis and heterophilic and histiocytic inflammation throughout multiple tissues. Gram stain identified small numbers of intra- and extracellular monomorphic Gram-negative 1 to 2 μm rod-shaped bacilli. Cytology of lung granuloma, kidney and testes imprints identified heterophilic inflammation with phagocytosis of small monomorphic bacilli and some heterophils exhibiting cytoplasmic projections indicative of heterophil extracellular traps (HETs). Initial phenotypic analysis of isolates from coelomic fluid cultures identified E. tarda. Subsequent molecular analysis of spleen, liver and intestine DNA using an E. tarda-specific endpoint PCR assay targeting the bacterial fimbrial subunit yielded a 115 bp band. Sequencing and BLASTN search revealed the sequence was identical (76/76) to E. tarda strain FL95-01 (GenBank acc. CP011359) and displayed 93% sequence identity (66/71) to Edwardsiella hoshinae strain ATCC 35051 (GenBank acc. CP011359). This is the first report of systemic edwardsiellosis in a lungfish with concurrent cytologically identified structures suggestive of HETs. © 2018 John Wiley & Sons Ltd.

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.

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.

Comparison of individual and pooled sampling methods for detecting bacterial pathogens of fish

USGS Publications Warehouse

Mumford, Sonia; Patterson, Chris; Evered, J.; Brunson, Ray; Levine, J.; Winton, J.

2005-01-01

Examination of finfish populations for viral and bacterial pathogens is an important component of fish disease control programs worldwide. Two methods are commonly used for collecting tissue samples for bacteriological culture, the currently accepted standards for detection of bacterial fish pathogens. The method specified in the Office International des Epizooties Manual of Diagnostic Tests for Aquatic Animals permits combining renal and splenic tissues from as many as 5 fish into pooled samples. The American Fisheries Society (AFS) Blue Book/US Fish and Wildlife Service (USFWS) Inspection Manual specifies the use of a bacteriological loop for collecting samples from the kidney of individual fish. An alternative would be to more fully utilize the pooled samples taken for virology. If implemented, this approach would provide substantial savings in labor and materials. To compare the relative performance of the AFS/USFWS method and this alternative approach, cultures of Yersinia ruckeri were used to establish low-level infections in groups of rainbow trout (Oncorhynchus mykiss) that were sampled by both methods. Yersinia ruckeri was cultured from 22 of 37 groups by at least 1 method. The loop method yielded 18 positive groups, with 1 group positive in the loop samples but negative in the pooled samples. The pooled samples produced 21 positive groups, with 4 groups positive in the pooled samples but negative in the loop samples. There was statistically significant agreement (Spearman coefficient 0.80, P < 0.001) in the relative ability of the 2 sampling methods to permit detection of low-level bacterial infections of rainbow trout.

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

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

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.

Oral and Anal Vaccination Confers Full Protection against Enteric Redmouth Disease (ERM) in Rainbow Trout

PubMed Central

Ohtani, Maki; Strøm, Helene Kragelund; Raida, Martin Kristian

2014-01-01

The effect of oral vaccines against bacterial fish diseases has been a topic for debate for decades. Recently both M-like cells and dendritic cells have been discovered in the intestine of rainbow trout. It is therefore likely that antigens reaching the intestine can be taken up and thereby induce immunity in orally vaccinated fish. The objective of this project was to investigate whether oral and anal vaccination of rainbow trout induces protection against an experimental waterborne infection with the pathogenic enterobacteria Yersinia ruckeri O1 biotype 1 the causative agent of enteric redmouth disease (ERM). Rainbow trout were orally vaccinated with AquaVac ERM Oral (MERCK Animal Health) or an experimental vaccine bacterin of Y. ruckeri O1. Both vaccines were tested with and without a booster vaccination four months post the primary vaccination. Furthermore, two groups of positive controls were included, one group receiving the experimental oral vaccine in a 50 times higher dose, and the other group receiving a single dose administered anally in order to bypass the stomach. Each group was bath challenged with 6.3×108 CFU/ml Y. ruckeri, six months post the primary vaccination. The challenge induced significant mortality in all the infected groups except for the groups vaccinated anally with a single dose or orally with the high dose of bacterin. Both of these groups had 100% survival. These results show that a low dose of Y. ruckeri bacterin induces full protection when the bacterin is administered anally. Oral vaccination also induces full protection, however, at a dose 50 times higher than if the fish were to be vaccinated anally. This indicates that much of the orally fed antigen is digested in the stomach before it reaches the second segment of the intestine where it can be taken up as immunogenic antigens and presented to lymphocytes. PMID:24705460

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

Comparative study of CXC chemokines modulation in brown trout (Salmo trutta) following infection with a bacterial or viral pathogen.

PubMed

Gorgoglione, Bartolomeo; Zahran, Eman; Taylor, Nick G H; Feist, Stephen W; Zou, Jun; Secombes, Christopher J

2016-03-01

Chemokine modulation in response to pathogens still needs to be fully characterised in fish, in view of the recently described novel chemokines present. This paper reports the first comparative study of CXC chemokine genes transcription in salmonids (brown trout), with a particular focus on the fish specific CXC chemokines (CXCL_F). Adopting new primer sets, optimised to specifically target mRNA, a RT-qPCR gene screening was carried out. Constitutive gene expression was assessed first in six tissues from SPF brown trout. Transcription modulation was next investigated in kidney and spleen during septicaemic infection induced by a RNA virus (Viral Haemorrhagic Septicaemia virus, genotype Ia) or by a Gram negative bacterium (Yersinia ruckeri, ser. O1/biot. 2). From each target organ specific pathogen burden, measured detecting VHSV-glycoprotein or Y. ruckeri 16S rRNA, and IFN-γ gene expression were analysed for their correlation to chemokine transcription. Both pathogens modulated CXC chemokine gene transcript levels, with marked up-regulation seen in some cases, and with both temporal and tissue specific effects apparent. For example, Y. ruckeri strongly induced chemokine transcription in spleen within 24h, whilst VHS generally induced the largest increases at 3d.p.i. in both tissues. This study gives clues to the role of the novel CXC chemokines, in comparison to the other known CXC chemokines in salmonids. Copyright © 2016 Elsevier Ltd. All rights reserved.

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

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

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.

Polymicrobial bacteremia caused by Escherichia coli, Edwardsiella tarda, and Shewanella putrefaciens.

PubMed

Wang, I-Kuan; Lee, Ming-Hsun; Chen, Yu-Ming; Huang, Chiu-Ching

2004-09-01

Edwardsiella tarda, a member of Enterobacteriaceae, is found in freshwater and marine environments and in animals living in these environments. This bacterium is primarily associated with gastrointestinal diseases, and has been isolated from stool specimens obtained from persons with or without clinical infectious diseases. Shewanella putrefaciens, a saprophytic gram-negative rod, is rarely responsible for clinical syndromes in humans. Debilitated status and exposure to aquatic environments are the major predisposing factors for E. tarda or S. putrefaciens infection. A 61-year-old woman was febrile with diarrhea 8 hours after ingesting shark meat, and two sets of blood cultures grew Escherichia coli, E. tarda and S. putrefaciens at the same time. She was successfully treated with antibiotics. We present this rare case of polymicrobial bacteremia caused by E. coli, E. tarda and S. putrefaciens without underlying disease, which is the first found in Taiwan. This rare case of febrile diarrhea with consequent polymicrobial bacteremia emphasizes that attention should always be extended to these unusual pathogens.

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.

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.

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.

Quantification of Campylobacter spp. in pig feces by direct real-time PCR with an internal control of extraction and amplification.

PubMed

Leblanc-Maridor, Mily; Garénaux, Amélie; Beaudeau, François; Chidaine, Bérangère; Seegers, Henri; Denis, Martine; Belloc, Catherine

2011-04-01

The rapid and direct quantification of Campylobacter spp. in complex substrates like feces or environmental samples is crucial to facilitate epidemiological studies on Campylobacter in pig production systems. We developed a real-time PCR assay for detecting and quantifying Campylobacter spp. directly in pig feces with the use of an internal control. Campylobacter spp. and Yersinia ruckeri primers-probes sets were designed and checked for specificity with diverse Campylobacter, related organisms, and other bacterial pathogens before being used in field samples. The quantification of Campylobacter spp. by the real-time PCR then was realized on 531 fecal samples obtained from experimentally and naturally infected pigs; the numeration of Campylobacter on Karmali plate was done in parallel. Yersinia ruckeri, used as bacterial internal control, was added to the samples before DNA extraction to control DNA-extraction and PCR-amplification. The sensitivity of the PCR assay was 10 genome copies. The established Campylobacter real-time PCR assay showed a 7-log-wide linear dynamic range of quantification (R²=0.99) with a detection limit of 200 Colony Forming Units of Campylobacter per gram of feces. A high correlation was found between the results obtained by real-time PCR and those by culture at both qualitative and quantitative levels. Moreover, DNA extraction followed by real-time PCR reduced the time needed for analysis to a few hours (within a working day). In conclusion, the real-time PCR developed in this study provides new tools for further epidemiological surveys to investigate the carriage and excretion of Campylobacter by pigs. Copyright © 2011 Elsevier B.V. All rights reserved.

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.

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.

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.

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

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.

Edwardsiella tarda Endocarditis Confirmed by Indium-111 White Blood Cell Scan: An Unusual Pathogen and Diagnostic Modality.

PubMed

Litton, Kayleigh M; Rogers, Bret A

2016-01-01

Edwardsiella tarda is a freshwater marine member of the family Enterobacteriaceae which often colonizes fish, lizards, snakes, and turtles but is an infrequent human pathogen. Indium-111- ((111)In-) labeled white blood cell (WBC) scintigraphy is an imaging modality which has a wide range of reported sensitivity and specificity (from 60 to 100% and from 68 to 92%, resp.) for diagnosing acute and chronic infection. We describe a case of suspected E. tarda prosthetic aortic valve and mitral valve endocarditis with probable vegetations and new mitral regurgitation on transthoracic and transesophageal echocardiograms which was supported with the use of (111)In-labeled WBC scintigraphy.

Differentiation of Yersinia enterocolitica biotype 1A from pathogenic Yersinia enterocolitica biotypes by detection of β-glucosidase activity: comparison of two chromogenic culture media and Vitek2.

PubMed

Karhukorpi, Jari; Päivänurmi, Marjut

2014-01-01

Aesculin hydrolysis (ESC) is one of the key reactions in differentiating pathogenic Yersinia enterocolitica biotypes 1B, 2, 3, 4 and 5 from the less-pathogenic biotype 1A. Because the ESC reaction is caused by β-glucosidase (βGLU) activity of the bacteria, we studied whether two commonly used methods (BBL CHROMagar Orientation and Vitek2 Gram-negative identification card) could be used in assessing βGLU activity of 74 Yersinia strains. Both methods were sensitive (100 % and 97 %) and specific (100 % and 100 %) in differentiating βGLU-positive YE BT1A from βGLU-negative Y. enterocolitica biotypes. For a subset of strains (n = 69), a new selective CHROMagar Yersinia showed excellent agreement with the strains' βGLU activity. Thus all the methods evaluated in this study may be used to differentiate between YE BT1A and other Y. enterocolitica biotypes.

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

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.

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.

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.

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).

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

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

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 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

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.

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

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

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

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.

Unique activity spectrum of colicin FY: all 110 characterized Yersinia enterocolitica isolates were colicin FY susceptible.

PubMed

Bosák, Juraj; Micenková, Lenka; Vrba, Martin; Ševčíková, Alena; Dědičová, Daniela; Garzetti, Debora; Šmajs, David

2013-01-01

Colicin FY is a plasmid encoded toxin that recognizes a yersinia-specific outer membrane protein (YiuR) as a receptor molecule. We have previously shown that the activity spectrum of colicin FY comprises strains of the genus Yersinia. In this study, we analyzed the activity of colicin FY against 110 Yersinia enterocolitica isolates differing in geographical origin and source. All isolates were characterized through analysis of 16S rRNA genes, serotyping, biotyping, restriction profiling of genomic DNA, detection of virulence markers and susceptibility to antibiotics. This confirmed the broad variability of the collection, in which all 110 Y. enterocolitica isolates, representing 77 various strains, were inhibited by colicin FY. Although isolates showed variable levels of susceptibility to colicin FY, it was not associated with any strain characteristic. The universal susceptibility of Y. enterocolitica strains to colicin FY together with the absence of activity towards strains outside the Yersinia genus suggests potential therapeutic applications for colicin FY.

Unique Activity Spectrum of Colicin FY: All 110 Characterized Yersinia enterocolitica Isolates Were Colicin FY Susceptible

PubMed Central

Bosák, Juraj; Micenková, Lenka; Vrba, Martin; Ševčíková, Alena; Dědičová, Daniela; Garzetti, Debora; Šmajs, David

2013-01-01

Colicin FY is a plasmid encoded toxin that recognizes a yersinia-specific outer membrane protein (YiuR) as a receptor molecule. We have previously shown that the activity spectrum of colicin FY comprises strains of the genus Yersinia. In this study, we analyzed the activity of colicin FY against 110 Yersinia enterocolitica isolates differing in geographical origin and source. All isolates were characterized through analysis of 16S rRNA genes, serotyping, biotyping, restriction profiling of genomic DNA, detection of virulence markers and susceptibility to antibiotics. This confirmed the broad variability of the collection, in which all 110 Y. enterocolitica isolates, representing 77 various strains, were inhibited by colicin FY. Although isolates showed variable levels of susceptibility to colicin FY, it was not associated with any strain characteristic. The universal susceptibility of Y. enterocolitica strains to colicin FY together with the absence of activity towards strains outside the Yersinia genus suggests potential therapeutic applications for colicin FY. PMID:24339971

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...

Metabolome strategy against Edwardsiella tarda infection through glucose-enhanced metabolic modulation in tilapias.

PubMed

Peng, Bo; Ma, Yan-Mei; Zhang, Jian-Ying; Li, Hui

2015-08-01

Edwardsiella tarda causes fish disease and great economic loss. However, metabolic strategy against the pathogen remains unexplored. In the present study, GC-MS based metabolomics was used to investigate the metabolic profile from tilapias infected by sublethal dose of E. tarda. The metabolic differences between the dying group and survival group allow the identification of key pathways and crucial metabolites during infections. More importantly, those metabolites may modulate the survival-related metabolome to enhance the anti-infective ability. Our data showed that tilapias generated two different strategies, survival-metabolome and death-metabolome, to encounter EIB202 infection, leading to differential outputs of the survival and dying. Glucose was the most crucial biomarker, which was upregulated and downregulated in the survival and dying groups, respectively. Exogenous glucose by injection or oral administration enhanced hosts' ability against EIB202 infection and increased the chances of survival. These findings highlight that host mounts the metabolic strategy to cope with bacterial infection, from which crucial biomarkers may be identified to enhance the metabolic strategy. Copyright © 2015 Elsevier Ltd. All rights reserved.

Identification of Differentially Abundant Proteins of Edwardsiella ictaluri during Iron Restriction

PubMed Central

Dumpala, Pradeep R.; Peterson, Brian C.; Lawrence, Mark L.; Karsi, Attila

2015-01-01

Edwardsiella ictaluri is a Gram-negative facultative anaerobe intracellular bacterium that causes enteric septicemia in channel catfish. Iron is an essential inorganic nutrient of bacteria and is crucial for bacterial invasion. Reduced availability of iron by the host may cause significant stress for bacterial pathogens and is considered a signal that leads to significant alteration in virulence gene expression. However, the precise effect of iron-restriction on E. ictaluri protein abundance is unknown. The purpose of this study was to identify differentially abundant proteins of E. ictaluri during in vitro iron-restricted conditions. We applied two-dimensional difference in gel electrophoresis (2D-DIGE) for determining differentially abundant proteins and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI TOF/TOF MS) for protein identification. Gene ontology and pathway-based functional modeling of differentially abundant proteins was also conducted. A total of 50 unique differentially abundant proteins at a minimum of 2-fold (p ≤ 0.05) difference in abundance due to iron-restriction were detected. The numbers of up- and down-regulated proteins were 37 and 13, respectively. We noted several proteins, including EsrB, LamB, MalM, MalE, FdaA, and TonB-dependent heme/hemoglobin receptor family proteins responded to iron restriction in E. ictaluri. PMID:26168192

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

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

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

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

Potentials and limits for the use of ozone as a fish disease control agent

USGS Publications Warehouse

Wedemeyer, Gary A.; Nelson, Nancy C.; Yasutake, Wm. T.

1979-01-01

Ozone and chlorine inactivation curves were determined in three types of freshwater at 20 C for the destruction of the fish pathogens Aeromonas salmonicida the etiologic agent of furunculosis, and Yersinia ruckeri the enteric redmouth bacterium (ERM). Ozone and chlorine inactivation curves were also obtained in the same water types at 10 C for the fish pathogenic viruses infectious hematopoietic necrosis (IHNV), and infectious pancreatic necrosis (IPNV). Acute toxicity tests using the rainbow trout as a representative salmonid revealed that ozone was highly toxic at the dose levels used. Partial chronic (3. mo.) testing revealed that ozone exposure at 2 μg/L causes only minimal physiological changes, none of which would be expected to compromise biological function.

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.

Detection of pathogenic Yersinia enterocolitica in pet Djungarian hamsters in Japan

PubMed Central

KAMEYAMA, Mitsuhiro; YABATA, Junko; OBANE, Noriko; OTSUKA, Hitoshi; NOMURA, Yasuharu

2016-01-01

The prevalence of Yersinia enterocolitica (Y. enterocolitica) and Yersinia pseudotuberculosis was examined in 151 pet animals including 108 rodents, 39 rabbits and four sugar gliders from 13 pet stores in the Yamaguchi Prefecture, Japan. Y. enterocolitica serogroup O:3 biotype 3 negative for the Voges-Proskauer reaction (O:3/3 variant VP-) was isolated from five Djungarian hamsters (Phodopus sungorus) raised at the same pet store. These pathogenic Y. enterocolitica isolates carried the virulence genes, yadA, ail and virF, and were shown to be clonal by pulsed-field gel electrophoresis with NotI digestion. This is a first report of pathogenic Y. enterocolitica O:3/3 variant VP- in pet Djungarian hamsters in Japan. PMID:27396397

Glucose enhances tilapia against Edwardsiella tarda infection through metabolome reprogramming.

PubMed

Zeng, Zao-hai; Du, Chao-Chao; Liu, Shi-Rao; Li, Hui; Peng, Xuan-Xian; Peng, Bo

2017-02-01

We have recently reported that the survival of tilapia, Oreochromis niloticus, during Edwardsiella tarda infection is tightly associated with their metabolome, where the survived O. niloticus has distinct metabolomic profile to dying O. niloticus. Glucose is the key metabolite to distinguish the survival- and dying-metabolome. More importantly, exogenous administration of glucose to the fish greatly enhances their survival for the infection, indicating the functional roles of glucose in metabolome repurposing, known as reprogramming metabolomics. However, the underlying information for the reprogramming is not yet available. Here, GC/MS based metabolomics is used to understand the mechanisms by which how exogenous glucose elevates O. niloticus, anti-infectious ability to E. tarda. Results showed that exogenous glucose promotes stearic acid and palmitic acid biosynthesis but attenuates TCA cycle to potentiate O. niloticus against bacterial infection, which is confirmed by the fact that exogenous stearic acid increases immune protection in O. niloticus against E. tarda infection in a manner of Mx protein. These results indicate that exogenous glucose reprograms O. niloticus anti-infective metabolome that characterizes elevation of stearic acid and palmitic acid and attenuation of the TCA cycle. Therefore, our results proposed a novel mechanism that glucose promotes unsaturated fatty acid biosynthesis to cope with infection, thereby highlighting a potential way of enhancing fish immunity in aquaculture. Copyright © 2016 Elsevier Ltd. 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

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.

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

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.

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.

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%.

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.

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.

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.

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.

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

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

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

Identification and validation of sRNAs in Edwardsiella tarda S08.

PubMed

Sun, Yuying; Zhang, Jiquan; Qin, Lei; Yan, Cui; Zhang, Xiaojun; Liu, Dandan

2017-01-01

Bacterial small non-coding RNAs (sRNAs) are known as novel regulators involved in virulence, stress responsibility, and so on. Recently, a lot of new researches have highlighted the critical roles of sRNAs in fine-tune gene regulation in both prokaryotes and eukaryotes. Edwardsiella tarda (E. tarda) is a gram-negative, intracellular pathogen that causes edwardsiellosis in fish. Thus far, no sRNA has been reported in E. tarda. The present study represents the first attempt to identify sRNAs in E. tarda S08. Ten sRNAs were validated by RNA sequencing and quantitative PCR (qPCR). ET_sRNA_1 and ET_sRNA_2 were homolous to tmRNA and GcvB, respectively. However, the other candidate sRNAs have not been reported till now. The cellular abundance of 10 validated sRNA was detected by qPCR at different growth phases to monitor their biosynthesis. Nine candidate sRNAs were expressed in the late-stage of exponential growth and stationary stages of growth (36~60 h). And the expression of the nine sRNAs was growth phase-dependent. But ET_sRNA_10 was almost expressed all the time and reached the highest peak at 48 h. Their targets were predicted by TargetRNA2 and each sRNA target contains some genes that directly or indirectly relate to virulence. These results preliminary showed that sRNAs probably play a regulatory role of virulence in E. tarda.

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.

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.

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.

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.

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.

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.

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...

Comparative analysis of Edwardsiella isolates from fish in the eastern United States identifies two distinct genetic taxa amongst organisms phenotypically classified as E. tarda

USGS Publications Warehouse

Griffin, Matt J.; Quiniou, Sylvie M.; Cody, Theresa; Tabuchi, Maki; Ware, Cynthia; Cipriano, Rocco C.; Mauel, Michael J.; Soto, Esteban

2013-01-01

Edwardsiella tarda, a Gram-negative member of the family Enterobacteriaceae, has been implicated in significant losses in aquaculture facilities worldwide. Here, we assessed the intra-specific variability of E. tarda isolates from 4 different fish species in the eastern United States. Repetitive sequence mediated PCR (rep-PCR) using 4 different primer sets (ERIC I & II, ERIC II, BOX, and GTG5) and multi-locus sequence analysis of 16S SSU rDNA, groEl, gyrA, gyrB, pho, pgi, pgm, and rpoA gene fragments identified two distinct genotypes of E. tarda (DNA group I; DNA group II). Isolates that fell into DNA group II demonstrated more similarity to E. ictaluri than DNA group I, which contained the reference E. tarda strain (ATCC #15947). Conventional PCR analysis using published E. tarda-specific primer sets yielded variable results, with several primer sets producing no observable amplification of target DNA from some isolates. Fluorometric determination of G + C content demonstrated 56.4% G + C content for DNA group I, 60.2% for DNA group II, and 58.4% for E. ictaluri. Surprisingly, these isolates were indistinguishable using conventional biochemical techniques, with all isolates demonstrating phenotypic characteristics consistent with E. tarda. Analysis using two commercial test kits identified multiple phenotypes, although no single metabolic characteristic could reliably discriminate between genetic groups. Additionally, anti-microbial susceptibility and fatty acid profiles did not demonstrate remarkable differences between groups. The significant genetic variation (<90% similarity at gyrA, gyrB, pho, phi and pgm; <40% similarity by rep-PCR) between these groups suggests organisms from DNA group II may represent an unrecognized, genetically distinct taxa of Edwardsiella that is phenotypically indistinguishable from E. tarda.

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

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.

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

Growth inhibition of Aeromonas salmonicida and Yersinia ruckeri by disinfectants containing peracetic acid

USDA-ARS?s Scientific Manuscript database

Peracetic acid is a therapeutic agent used for disinfection, but it must be investigated in order to mitigate diseases without harmful effects to the fish. These agents should not leave dangerous residues in the environment in order to successfully contribute to sustainable aquaculture. The aim of ...

Growth inhibition of Aeromonas salmonicida and Yersinia ruckeri by disinfectants containing peracetic acid

USDA-ARS?s Scientific Manuscript database

Peracetic acid is a therapeutic agent used for disinfection in aquaculture, but it must be investigated thoroughly in order to mitigate diseases without harmful effects to fish. These agents should not leave dangerous residues in the environment in order to successfully contribute to sustainable aq...

Growth inhibition of Aeromonas salmonicida and Yersinia ruckeri by disinfectants containing peracetic acid

USDA-ARS?s Scientific Manuscript database

Peracetic acid (PAA) is an agent used for disinfection in aquaculture. PAA contributes to sustainable aquaculture, because it releases no harmful residue in the environment. However, there is lack of guideline about the effective application of different PAA products against various pathogens in p...

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.

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

Mortality and pathology in brown bullheads Amieurus nebulosus associated with a spontaneous Edwardsiella ictaluri outbreak under tank culture conditions

USGS Publications Warehouse

Iwanowicz, L.R.; Griffin, A.R.; Cartwright, Deborah D.; Blazer, V.S.

2006-01-01

Brown bullheads Amieurus nebulosus (family Ictaluridae) are commonly used as a sentinel of environmental contamination. These fish are not generally cultured under laboratory conditions and little is known about their disease susceptibility. Here we report an outbreak of disease due to Edwardsiella ictaluri in a laboratory population of tank-reared, wild-caught brown bullheads. The isolate was positively identified as E. ictaluri using standard bacteriological substrate utilization tests and a monoclonal antibody specific for this bacterium. This pathogen causes a significant disease in channel catfish Ictalurus punctatus and is associated with disease in other ictalurid and non-ictalurid fishes. It appears that E. ictaluri is also a significant pathogen in brown bullheads and produces clinical signs and lesions similar but not identical to those observed in channel catfish. Since commercial sources of bullheads for laboratory tank studies are not available, precautions should be taken to prevent potential E. ictaluri disease outbreaks from wild-caught bullheads intended for laboratory research. ?? Inter-Research 2006.

Mortality and pathology in brown bullheads Amieurus nebulosus associated with a spontaneous Edwardsiella ictaluri outbreak under tank culture conditions.

PubMed

Iwanowicz, Luke R; Griffin, Alison R; Cartwright, Deborah D; Blazer, Vicki S

2006-06-23

Brown bullheads Amieurus nebulosus (family Ictaluridae) are commonly used as a sentinel of environmental contamination. These fish are not generally cultured under laboratory conditions and little is known about their disease susceptibility. Here we report an outbreak of disease due to Edwardsiella ictaluri in a laboratory population of tank-reared, wild-caught brown bullheads. The isolate was positively identified as E. ictaluri using standard bacteriological substrate utilization tests and a monoclonal antibody specific for this bacterium. This pathogen causes a significant disease in channel catfish Ictalurus punctatus and is associated with disease in other ictalurid and non-ictalurid fishes. It appears that E. ictaluri is also a significant pathogen in brown bullheads and produces clinical signs and lesions similar but not identical to those observed in channel catfish. Since commercial sources of bullheads for laboratory tank studies are not available, precautions should be taken to prevent potential E. ictaluri disease outbreaks from wild-caught bullheads intended for laboratory research.

YebC controls virulence by activating T3SS gene expression in the pathogen Edwardsiella piscicida.

PubMed

Wei, Lifan; Wu, Yanyan; Qiao, Haoxian; Xu, Wensheng; Zhang, Yuanxing; Liu, Xiaohong; Wang, Qiyao

2018-06-12

Edwardsiella piscicida is an infectious Gram-negative bacterium that causes great losses to the aquaculture industry worldwide. Based on pattern analysis of conditional essentiality (PACE), a new method for transposon insertion sequencing (Tn-seq) data analysis, we investigated the genome-wide genetic requirements during the dynamic process of infection and colonization in turbot in this study. As a result, disruption of ETAE_1437 was discovered to lead to substantially reduced colonization, which was similar to the in vivo dynamic patterns of the mutants of T3SS or T6SS. Bioinformatics analysis indicated that ETAE_1437 is a YebC/PmpR family regulator. Moreover, we found that ETAE_1437 not only regulated quorum sensing by directly binding to the edwR promoter region but also activated T3SS expression by directly binding to the promoter region of the T3SS gene ETAE_0873. In addition, ETAE_1437 mutants exhibited substantial colonization defects and significantly decreased virulence in turbot. Overall, this study identified ETAE_1437 as a novel virulence regulator in E. piscicida and enriched our understanding of the pathogenesis of E. piscicida in fish. We thus reannotated ETAE_1437 as YebC.

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

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

[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

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.

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

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.

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

2012-02-21

Disease progression of primary pneumonic plague is biphasic, consisting of a preinflammatory and a proinflammatory phase. During the long preinflammatory phase, bacteria replicate to high levels, seemingly uninhibited by normal pulmonary defenses. In a coinfection model of pneumonic plague, it appears that Yersinia pestis quickly creates a localized, dominant anti-inflammatory state that allows for the survival and rapid growth of both itself and normally avirulent organisms. Yersinia pseudotuberculosis, the relatively recent progenitor of Y. pestis, shows no similar trans-complementation effect, which is unprecedented among other respiratory pathogens. We demonstrate that the effectors secreted by the Ysc type III secretion system are necessary but not sufficient to mediate this apparent immunosuppression. Even an unbiased negative selection screen using a vast pool of Y. pestis mutants revealed no selection against any known virulence genes, demonstrating the transformation of the lung from a highly restrictive to a generally permissive environment during the preinflammatory phase of pneumonic plague.

An Encapsulated Yersinia pseudotuberculosis Is a Highly Efficient Vaccine against Pneumonic Plague

PubMed Central

Derbise, Anne; Cerdà Marín, Alba; Ave, Patrick; Blisnick, Thierry; Huerre, Michel; Carniel, Elisabeth; Demeure, Christian E.

2012-01-01

Background 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. Methodology and Principal Findings 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×LD50 of the fully virulent Y. pestis CO92 strain) and 94% against a high challenge dose (3,300×LD50). Both F1 and other Yersinia antigens were recognized and V674pF1 efficiently protected against a F1-negative Y. pestis. Conclusions and Significance 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. PMID:22348169

Antigenic profiling of Yersinia pestis infection in the Wyoming coyote (Canis latrans)

USGS Publications Warehouse

Vernati, G.; Edwards, W.H.; Rocke, T.E.; Little, S.F.; Andrews, G.P.

2011-01-01

Although Yersinia pestis is classified as a "high-virulence" pathogen, some host species are variably susceptible to disease. Coyotes (Canis latrans) exhibit mild, if any, symptoms during infection, but antibody production occurs postinfection. This immune response has been reported to be against the F1 capsule, although little subsequent characterization has been conducted. To further define the nature of coyote humoral immunity to plague, qualitative serology was conducted to assess the antiplague antibody repertoire. Humoral responses to six plasmid-encoded Y. pestis virulence factors were first examined. Of 20 individual immune coyotes, 90% were reactive to at least one other antigen in the panel other than F1. The frequency of reactivity to low calcium response plasmid (pLcr)-encoded Yersinia protein kinase A (YpkA) and Yersinia outer protein D (YopD) was significantly greater than that previously observed in a murine model for plague. Additionally, both V antigen and plasminogen activator were reactive with over half of the serum samples tested. Reactivity to F1 was markedly less frequent in coyotes (35%). Twenty previously tested antibody-negative samples were also examined. While the majority were negative across the panel, 15% were positive for 1-3 non-F1 antigens. In vivo-induced antigen technology employed to identify novel chromosomal genes of Y. pestis that are up-regulated during infection resulted in the identification of five proteins, including a flagellar component (FliP) that was uniquely reactive with the coyote serum compared with immune serum from two other host species. Collectively, these data suggest that humoral immunity to pLcr-encoded antigens and the pesticin plasmid (pPst)-encoded Pla antigen may be relevant to plague resistance in coyotes. The serologic profile of Y. pestis chromosomal antigens up-regulated in vivo specific to C. latrans may provide insight into the differences in the pathogen-host responses during Y. pestis infection.

Tripeptide inhibitors of Yersinia protein-tyrosine phosphatase.

PubMed

Lee, Kyeong; Gao, Yang; Yao, Zhu-Jun; Phan, Jason; Wu, Li; Liang, Jiao; Waugh, David S; Zhang, Zhong-Yin; Burke, Terrence R

2003-08-04

The protein-tyrosine phosphatase (PTP) 'YopH' is a virulence factor of Yersinia pestis, the causative agent of plague. Potential use of Yersinia as a bioterrorism agent renders YopH inhibitors of therapeutic importance. Previously, we had examined the inhibitory potencies of a variety of phosphotyrosyl (pTyr) mimetics against the human PTP1B enzyme by displaying them in the EGFR-derived hexapeptide sequence, 'Ac-Asp-Ala-Asp-Glu-Xxx-Leu-amide', where Xxx=pTyr mimetic. The poor inhibitory potencies of certain of these pTyr mimetics were attributed to restricted orientation within the PTP1B catalytic pocket incurred by extensive peripheral interaction of the hexapeptide platform. Utilizing the smaller tripeptide platform, 'Fmoc-Glu-Xxx-Leu-amide' we demonstrate herein that several of the low affinity hexapeptide-expressed pTyr mimetics exhibit high PTP1B affinity within the context of the tripeptide platform. Of particular note, the mono-anionic 4-(carboxydifluoromethyl)Phe residue exhibits affinity equivalent to the di-anionic F(2)Pmp residue, which had previously been among the most potent PTP-binding motifs. Against YopH, it was found that all tripeptides having Glu residues with an unprotected side chain carboxyl were inactive. Alternatively, in their Glu-OBn ester forms, several of the tripeptides exhibited good YopH affinity with the mono-anionic peptide, Fmoc-Glu(OBn)-Xxx-Leu-amide, where Xxx=4-(carboxymethyloxy)Phe providing an IC(50) value of 2.8 microM. One concern with such inhibitors is that they may potentially function by non-specific mechanisms. Studies with representative inhibitors, while failing to provide evidence of a non-specific promiscuous mode of inhibition, did indicate that non-classical inhibition may be involved.

Hfq Regulates Biofilm Gut Blockage That Facilitates Flea-Borne Transmission of Yersinia pestis

PubMed Central

Rempe, Katherine A.; Hinz, Angela K.

2012-01-01

The plague bacillus Yersinia pestis can achieve transmission by biofilm blockage of the foregut proventriculus of its flea vector. Hfq is revealed to be essential for biofilm blockage formation and acquisition and fitness of Y. pestis during flea gut infection, consistent with posttranscriptional regulatory mechanisms in plague transmission. PMID:22328669

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

Optimization of protectant, salinity and freezing condition for freeze-drying preservation of Edwardsiella tarda

NASA Astrophysics Data System (ADS)

Yu, Yongxiang; Zhang, Zheng; Wang, Yingeng; Liao, Meijie; Li, Bin; Xue, Liangyi

2017-10-01

Novel preservation condition without ultra-low temperature is needed for the study of pathogen in marine fishes. Freeze-drying is such a method usually used for preservation of terrigenous bacteria. However, studies using freeze-drying method to preserving marine microorganisms remain very limited. In this study, we optimized the composition of protectants during the freeze-drying of Edwardsiella tarda, a fish pathogen that causes systemic infection in marine fishes. We found that the optimal composition of protectant mixture contained trehalose (8.0%), skim milk (12.0%), sodium citrate (2.0%), serum (12.0%) and PVP (2.0%). Orthogonal and interaction analyses demonstrated the interaction between serum and skim milk or sodium citrate. The highest survival rate of E. tarda was observed when the concentration of NaCl was 10.0, 30.0 and between 5.0 and 10.0 g L-1 for preparing TSB medium, E. tarda suspension and protectant mixture, respectively. When E. tarda was frozen at -80°C or -40°C for 6 h, its survival rate was higher than that under other tested conditions. Under the optimized conditions, when the protectant mixture was used during freeze-drying process, the survival rate (79.63%-82.30%) of E. tarda was significantly higher than that obtained using single protectant. Scanning electron microscopy (SEM) image indicated that E. tarda was embedded in thick matrix with detectable aggregation. In sum, the protectant mixture may be used as a novel cryoprotective additive for E. tarda.

IQGAP1 is important for activation of caspase-1 in macrophages and is targeted by Yersinia pestis type III effector YopM.

PubMed

Chung, Lawton K; Philip, Naomi H; Schmidt, Valentina A; Koller, Antonius; Strowig, Till; Flavell, Richard A; Brodsky, Igor E; Bliska, James B

2014-07-01

YopM is a leucine-rich repeat (LRR)-containing effector in several Yersinia species, including Yersinia pestis and Y. pseudotuberculosis. Different Yersinia strains encode distinct YopM isoforms with variable numbers of LRRs but conserved C-terminal tails. A 15-LRR isoform in Y. pseudotuberculosis YPIII was recently shown to bind and inhibit caspase-1 via a YLTD motif in LRR 10, and attenuation of YopM(-) YPIII was reversed in mice lacking caspase-1, indicating that caspase-1 inhibition is a major virulence function of YopM(YPIII). To determine if other YopM proteins inhibit caspase-1, we utilized Y. pseudotuberculosis strains natively expressing a 21-LRR isoform lacking the YLTD motif (YopM(32777)) or ectopically expressing a Y. pestis 15-LRR version with a functional (YopM(KIM)) or inactivated (YopM(KIM) D271A) YLTD motif. Results of mouse and macrophage infections with these strains showed that YopM(32777), YopM(KIM), and YopM(KIM) D271A inhibit caspase-1 activation, indicating that the YLTD motif is dispensable for this activity. Analysis of YopM(KIM) deletion variants revealed that LRRs 6 to 15 and the C-terminal tail are required to inhibit caspase-1 activation. YopM(32777), YopM(KIM), and YopM(KIM) deletion variants were purified, and binding partners in macrophage lysates were identified. Caspase-1 bound to YopM(KIM) but not YopM(32777). Additionally, YopM(KIM) bound IQGAP1 and the use of Iqgap1(-/-) macrophages revealed that this scaffolding protein is important for caspase-1 activation upon infection with YopM(-) Y. pseudotuberculosis. Thus, while multiple YopM isoforms inhibit caspase-1 activation, their variable LRR domains bind different host proteins to perform this function and the LRRs of YopM(KIM) target IQGAP1, a novel regulator of caspase-1, in macrophages. Importance: Activation of caspase-1, mediated by macromolecular complexes termed inflammasomes, is important for innate immune defense against pathogens. Pathogens can, in turn, subvert

Application of the flow cytometry for determination of the amount of DNA in Yersinia pestis cells under the influence of serotonin (5-hydroxytryptamine)

NASA Astrophysics Data System (ADS)

Korsukov, Vladimir N.; Shchukovskaya, Tatyana N.; Kravtsov, Alexander L.; Popov, Youri A.

2002-07-01

Using flow cytometry a low DNA content in inoculated Yersinia pestis EV cells have been shown at the beginning of culture in Hottinger broth pH 7.2. The dependence serotonin action of its concentration on DNA content have been demonstrated. Serotonin accelerated Yersinia pestis culture growth during cultivation in Hottinger broth pH 7.2 both at 28 degrees C and 37 degrees C at concentration of 10-5 M.

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

Inactivation of avirulent pgm+ and delta pgm Yersinia pestis by ultraviolet light (UV-C)

USDA-ARS?s Scientific Manuscript database

Yersinia pestis is the causative agent of bubonic plague. Though not considered a foodborne pathogen, Y. pestis can survive, and even grow, in some foods, and the foodborne route of transmission is not without precedent. As such, concerns exist over the possible intentional contamination of foods wi...

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...

Yersinia pestis--etiologic agent of plague.

PubMed Central

Perry, R D; Fetherston, J D

1997-01-01

Plague is a widespread zoonotic disease that is caused by Yersinia pestis and has had devastating effects on the human population throughout history. Disappearance of the disease is unlikely due to the wide range of mammalian hosts and their attendant fleas. The flea/rodent life cycle of Y. pestis, a gram-negative obligate pathogen, exposes it to very different environmental conditions and has resulted in some novel traits facilitating transmission and infection. Studies characterizing virulence determinants of Y. pestis have identified novel mechanisms for overcoming host defenses. Regulatory systems controlling the expression of some of these virulence factors have proven quite complex. These areas of research have provide new insights into the host-parasite relationship. This review will update our present understanding of the history, etiology, epidemiology, clinical aspects, and public health issues of plague. PMID:8993858

Yersinia pestis Targets the Host Endosome Recycling Pathway during the Biogenesis of the Yersinia-Containing Vacuole To Avoid Killing by Macrophages

PubMed Central

Connor, Michael G.; Pulsifer, Amanda R.; Ceresa, Brian K.

2018-01-01

ABSTRACT Yersinia pestis has evolved many strategies to evade the innate immune system. One of these strategies is the ability to survive within macrophages. Upon phagocytosis, Y. pestis prevents phagolysosome maturation and establishes a modified compartment termed the Yersinia-containing vacuole (YCV). Y. pestis actively inhibits the acidification of this compartment, and eventually, the YCV transitions from a tight-fitting vacuole into a spacious replicative vacuole. The mechanisms to generate the YCV have not been defined. However, we hypothesized that YCV biogenesis requires Y. pestis interactions with specific host factors to subvert normal vesicular trafficking. In order to identify these factors, we performed a genome-wide RNA interference (RNAi) screen to identify host factors required for Y. pestis survival in macrophages. This screen revealed that 71 host proteins are required for intracellular survival of Y. pestis. Of particular interest was the enrichment for genes involved in endosome recycling. Moreover, we demonstrated that Y. pestis actively recruits Rab4a and Rab11b to the YCV in a type three secretion system-independent manner, indicating remodeling of the YCV by Y. pestis to resemble a recycling endosome. While recruitment of Rab4a was necessary to inhibit YCV acidification and lysosomal fusion early during infection, Rab11b appeared to contribute to later stages of YCV biogenesis. We also discovered that Y. pestis disrupts global host endocytic recycling in macrophages, possibly through sequestration of Rab11b, and this process is required for bacterial replication. These data provide the first evidence that Y. pestis targets the host endocytic recycling pathway to avoid phagolysosomal maturation and generate the YCV. PMID:29463656

Occurrence of enteric redmouth disease in rainbow trout (Oncorhynchus mykiss) on farms in Croatia.

PubMed

Oraić, D; Zrncić, Snjezana; Sostarić, B; Bazulić, D; Lipej, Z

2002-01-01

During the spring of 1996 and autumn of 1997 unusual mortality outbreaks among rainbow trout fry and yearlings occurred at two different trout farms, resulting in mortality of 20 and 10 per cent, respectively. Generally, the affected fish, swimming at the water surface, were reluctant to eat and were dark pigmented with visible haemorrhages around and within the oral cavity. Bacterial isolates from moribund fish from both cases were identified as Yersinia ruckeri by standard biochemical tests and API 20E. The isolated strains were found to be sensitive to tetracycline, chloramphenicol, co-trimoxazole, nalidixic acid, flumequine, enrofloxacin, carbenicillin and gentamicin. Microplate agglutination assay confirmed that both isolates belonged to serotype O1. The pathogenicity of the isolated bacteria was confirmed by challenge experiment. Titres of specific antibodies were determined in the sera of survivors. The titre was highest on the 21st day postchallenge and was detectable until the 81st day.

Immunomodulatory Yersinia outer proteins (Yops)–useful tools for bacteria and humans alike

PubMed Central

Grabowski, Benjamin; Schmidt, M. Alexander; Rüter, Christian

2017-01-01

ABSTRACT Human-pathogenic Yersinia produce plasmid-encoded Yersinia outer proteins (Yops), which are necessary to down-regulate anti-bacterial responses that constrict bacterial survival in the host. These Yops are effectively translocated directly from the bacterial into the target cell cytosol by the type III secretion system (T3SS). Cell-penetrating peptides (CPPs) in contrast are characterized by their ability to autonomously cross cell membranes and to transport cargo – independent of additional translocation systems. The recent discovery of bacterial cell-penetrating effector proteins (CPEs) – with the prototype being the T3SS effector protein YopM – established a new class of autonomously translocating immunomodulatory proteins. CPEs represent a vast source of potential self-delivering, anti-inflammatory therapeutics. In this review, we give an update on the characteristic features of the plasmid-encoded Yops and, based on recent findings, propose the further development of these proteins for potential therapeutic applications as natural or artificial cell-penetrating forms of Yops might be of value as bacteria-derived biologics. PMID:28296562

Expression and Association of the Yersinia pestis Translocon Proteins, YopB and YopD, Are Facilitated by Nanolipoprotein Particles

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

Coleman, Matthew A.; Cappuccio, Jenny A.; Blanchette, Craig D.

Yersinia pestis enters host cells and evades host defenses, in part, through interactions between Yersinia pestis proteins and host membranes. One such interaction is through the type III secretion system, which uses a highly conserved and ordered complex for Yersinia pestis outer membrane effector protein translocation called the injectisome. The portion of the injectisome that interacts directly with host cell membranes is referred to as the translocon. The translocon is believed to form a pore allowing effector molecules to enter host cells. To facilitate mechanistic studies of the translocon, we have developed a cell-free approach for expressing translocon pore proteinsmore » as a complex supported in a bilayer membrane mimetic nano-scaffold known as a nanolipoprotein particle (NLP) Initial results show cell-free expression of Yersinia pestis outer membrane proteins YopB and YopD was enhanced in the presence of liposomes. However, these complexes tended to aggregate and precipitate. With the addition of co-expressed (NLP) forming components, the YopB and/or YopD complex was rendered soluble, increasing the yield of protein for biophysical studies. Biophysical methods such as Atomic Force Microscopy and Fluorescence Correlation Spectroscopy were used to confirm that the soluble YopB/D complex was associated with NLPs. An interaction between the YopB/D complex and NLP was validated by immunoprecipitation. The YopB/D translocon complex embedded in a NLP provides a platform for protein interaction studies between pathogen and host proteins. Ultimately, these studies will help elucidate the poorly understood mechanism which enables this pathogen to inject effector proteins into host cells, thus evading host defenses.« less

Expression and Association of the Yersinia pestis Translocon Proteins, YopB and YopD, Are Facilitated by Nanolipoprotein Particles

DOE PAGES

Coleman, Matthew A.; Cappuccio, Jenny A.; Blanchette, Craig D.; ...

2016-03-25

Yersinia pestis enters host cells and evades host defenses, in part, through interactions between Yersinia pestis proteins and host membranes. One such interaction is through the type III secretion system, which uses a highly conserved and ordered complex for Yersinia pestis outer membrane effector protein translocation called the injectisome. The portion of the injectisome that interacts directly with host cell membranes is referred to as the translocon. The translocon is believed to form a pore allowing effector molecules to enter host cells. To facilitate mechanistic studies of the translocon, we have developed a cell-free approach for expressing translocon pore proteinsmore » as a complex supported in a bilayer membrane mimetic nano-scaffold known as a nanolipoprotein particle (NLP) Initial results show cell-free expression of Yersinia pestis outer membrane proteins YopB and YopD was enhanced in the presence of liposomes. However, these complexes tended to aggregate and precipitate. With the addition of co-expressed (NLP) forming components, the YopB and/or YopD complex was rendered soluble, increasing the yield of protein for biophysical studies. Biophysical methods such as Atomic Force Microscopy and Fluorescence Correlation Spectroscopy were used to confirm that the soluble YopB/D complex was associated with NLPs. An interaction between the YopB/D complex and NLP was validated by immunoprecipitation. The YopB/D translocon complex embedded in a NLP provides a platform for protein interaction studies between pathogen and host proteins. Ultimately, these studies will help elucidate the poorly understood mechanism which enables this pathogen to inject effector proteins into host cells, thus evading host defenses.« less

A bibliography of literature pertaining to plague (Yersinia pestis)

USGS Publications Warehouse

Ellison, Laura E.; Frank, Megan K. Eberhardt

2011-01-01

Plague is an acute and often fatal zoonotic disease caused by the bacterium Yersinia pestis. Y. pestis mainly cycles between small mammals and their fleas; however, it has the potential to infect humans and frequently causes fatalities if left untreated. It is often considered a disease of the past; however, since the late 1800s, plagueis geographic range has expanded greatly, posing new threats in previously unaffected regions of the world, including the Western United States. A literature search was conducted using Internet resources and databases. The keywords chosen for the searches included plague, Yersinia pestis, management, control, wildlife, prairie dogs, fleas, North America, and mammals. Keywords were used alone or in combination with the other terms. Although this search pertains mostly to North America, citations were included from the international research community, as well. Databases and search engines used included Google (http://www.google.com), Google Scholar (http://scholar.google.com), SciVerse Scopus (http://www.scopus.com), ISI Web of Knowledge (http://apps.isiknowledge.com), and the USGS Library's Digital Desktop (http://library.usgs.gov). The literature-cited sections of manuscripts obtained from keyword searches were cross-referenced to identify additional citations or gray literature that was missed by the Internet search engines. This Open-File Report, published as an Internet-accessible bibliography, is intended to be periodically updated with new citations or older references that may have been missed during this compilation. Hence, the authors would be grateful to receive notice of any new or old papers that the audience (users) think need to be included.

Yersinia philomiragia sp. n., a new member of the Pasteurella group of bacteria, naturally pathogenic for the muskrat (Ondatra zibethica)

USGS Publications Warehouse

Jensen, W.I.; Owen, C.R.; Jellison, W.L.

1969-01-01

A bacterium experimentally pathogenic for muskrats (Ondatra zibethica), white mice, mountain voles (Microtus montanus), and deer mice (Peromyscus maniculatus) was isolated from the tissues of a sick muskrat captured on the Bear River Migratory Bird Refuge (Brigham City, Utah) and from four surface water samples collected within 15 miles of that point. In culture, the cells are chiefly coccoid, but in the tissues of muskrats and voles they resemble the bizarre forms of Yersinia pestis, except for their smaller size. The characteristics of the organism are described and the name Yersinia philomiragia sp. n. is proposed.

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.

Oral vaccination with different antigens from Yersinia pestis KIM delivered by live attenuated Salmonella typhimurium elicits a protective immune response against plague.

PubMed

Branger, Christine G; Fetherston, Jacqueline D; Perry, Robert D; Curtiss, Roy

2007-01-01

The use of live recombinant Salmonella attenuated vaccine (RASV) encoding Yersinia proteins is a promising new approach for the vaccination against Yersinia pestis. We have tested the efficacy of 2 proteins, Psn and a portion of LcrV in protecting mice against virulent Yersinia pestis challenge. To remove the immunosuppressive properties of LcrV protein, the lcrV gene, without the TLR2 receptor sequence, was cloned into a beta-lactamase secretion vector. Immunizations were performed with RSAV expressing LcrV or Psn. Challenge with a virulent Y. pestis strain was performed 4 weeks after the last immunization. Our results show that the truncated LcrV protein delivered by RASV is sufficient to afford a full protective immune response in a mouse model of bubonic plague and the Psn protein afforded partial protection in a non-optimized system. This finding should facilitate the design and development of a new generation of vaccines against Y. pestis.

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.

TolC plays a crucial role in immune protection conferred by Edwardsiella tarda whole-cell vaccines.

PubMed

Wang, Chao; Peng, Bo; Li, Hui; Peng, Xuan-Xian

2016-07-12

Although vaccines developed from live organisms have better efficacy than those developed from dead organisms, the mechanisms underlying this differential efficacy remain unexplored. In this study, we combined sub-immunoproteomics with immune challenge to investigate the action of the outer membrane proteome in the immune protection conferred by four Edwardsiella tarda whole-cell vaccines prepared via different treatments and to identify protective immunogens that play a key role in this immune protection. Thirteen spots representing five outer membrane proteins and one cytoplasmic protein were identified, and it was found that their abundance was altered in relation with the immune protective abilities of the four vaccines. Among these proteins, TolC and OmpA were found to be the key immunogens conferring the first and second highest degrees of protection, respectively. TolC was detected in the two effective vaccines (live and inactivated-30-F). The total antiserum and anti-OmpA titers were higher for the two effective vaccines than for the two ineffective vaccines (inactivated-80-F and inactivated-100). Further evidence demonstrated that the live and inactivated-30-F vaccines demonstrated stronger abilities to induce CD8+ and CD4+ T cell differentiation than the other two evaluated vaccines. Our results indicate that the outer membrane proteome changes dramatically following different treatments, which contributes to the effectiveness of whole-cell vaccines.

Yersinia pestis CO92 delta yopH is a potent live, attenuated plague vaccine.

PubMed

Bubeck, Sarah S; Dube, Peter H

2007-09-01

An in-frame deletion of the yopH gene in Yersinia pestis CO92 attenuates virulence in both bubonic and pneumonic plague models. When it is used as a live, attenuated vaccine, CO92 delta yopH provides a high degree of protection from parental and respiratory challenge with Y. pestis CO92.

A Csr-type regulatory system, including small non-coding RNAs, regulates the global virulence regulator RovA of Yersinia pseudotuberculosis through RovM.

PubMed

Heroven, Ann Kathrin; Böhme, Katja; Rohde, Manfred; Dersch, Petra

2008-06-01

The MarR-type regulator RovA controls expression of virulence genes of Yersinia pseudotuberculosis in response to environmental signals. Using a genetic strategy to discover components that influence rovA expression, we identified new regulatory factors with homology to components of the carbon storage regulator system (Csr). We showed that overexpression of a CsrB- or a CsrC-type RNA activates rovA, whereas a CsrA-like protein represses RovA synthesis. We further demonstrate that influence of the Csr system on rovA is indirect and occurs through control of the LysR regulator RovM, which inhibits rovA transcription. The CsrA protein had also a major influence on the motility of Yersinia, which was independent of RovM. The CsrB and CsrC RNAs are differentially expressed in Yersinia. CsrC is highly induced in complex but not in minimal media, indicating that medium-dependent rovM expression is mediated through CsrC. CsrB synthesis is generally very low. However, overexpression of the response regulator UvrY was found to activate CsrB production, which in turn represses CsrC synthesis independent of the growth medium. In summary, the post-transcriptional Csr-type components were shown to be key regulators in the co-ordinated environmental control of physiological processes and virulence factors, which are crucial for the initiation of Yersinia infections.

Microarray Bactericidal Testing of Natural Products Against Yersinia intermedia and Bacillus anthracis

DTIC Science & Technology

2002-01-01

Based Preservation Systems and Probiotic Bacteria. In Food Microbiology: Fundamentals and Frontiers. M. P. Doyle, L.R. Beuchat and T.J. Montville...Microarray Bactericidal Testing of Natural Products Against Yersinia intermedia and Bacillus anthracis I.J. Fry1, F.K. Lee2, A. Turetsky2 and J.J...effective protection against biological warfare agents (BWA’s), natural products with a historical record of bactericidal efficacy such as

MarA-Like Regulator of Multidrug Resistance in Yersinia pestis

PubMed Central

Udani, Rupa A.; Levy, Stuart B.

2006-01-01

MarA47Yp from Yersinia pestis, showing 47% identity to Escherichia coli MarA in its N terminus, caused resistance to antibiotics and to organic solvents when expressed in both E. coli and Y. pestis. Resistance was linked to increased expression of the AcrAB multidrug efflux pump. In four of five spontaneous multidrug-resistant mutants of Y. pestis independently selected by growth on tetracycline, the marA47Yp gene was overexpressed. The findings suggest that marA47Yp is a marA ortholog in Y. pestis. PMID:16940090

MarA-like regulator of multidrug resistance in Yersinia pestis.

PubMed

Udani, Rupa A; Levy, Stuart B

2006-09-01

MarA47(Yp) from Yersinia pestis, showing 47% identity to Escherichia coli MarA in its N terminus, caused resistance to antibiotics and to organic solvents when expressed in both E. coli and Y. pestis. Resistance was linked to increased expression of the AcrAB multidrug efflux pump. In four of five spontaneous multidrug-resistant mutants of Y. pestis independently selected by growth on tetracycline, the marA47(Yp) gene was overexpressed. The findings suggest that marA47(Yp) is a marA ortholog in Y. pestis.

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

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

[Standard algorithm of molecular typing of Yersinia pestis strains].

PubMed

Eroshenko, G A; Odinokov, G N; Kukleva, L M; Pavlova, A I; Krasnov, Ia M; Shavina, N Iu; Guseva, N P; Vinogradova, N A; Kutyrev, V V

2012-01-01

Development of the standard algorithm of molecular typing of Yersinia pestis that ensures establishing of subspecies, biovar and focus membership of the studied isolate. Determination of the characteristic strain genotypes of plague infectious agent of main and nonmain subspecies from various natural foci of plague of the Russian Federation and the near abroad. Genotyping of 192 natural Y. pestis strains of main and nonmain subspecies was performed by using PCR methods, multilocus sequencing and multilocus analysis of variable tandem repeat number. A standard algorithm of molecular typing of plague infectious agent including several stages of Yersinia pestis differentiation by membership: in main and nonmain subspecies, various biovars of the main subspecies, specific subspecies; natural foci and geographic territories was developed. The algorithm is based on 3 typing methods--PCR, multilocus sequence typing and multilocus analysis of variable tandem repeat number using standard DNA targets--life support genes (terC, ilvN, inv, glpD, napA, rhaS and araC) and 7 loci of variable tandem repeats (ms01, ms04, ms06, ms07, ms46, ms62, ms70). The effectiveness of the developed algorithm is shown on the large number of natural Y. pestis strains. Characteristic sequence types of Y. pestis strains of various subspecies and biovars as well as MLVA7 genotypes of strains from natural foci of plague of the Russian Federation and the near abroad were established. The application of the developed algorithm will increase the effectiveness of epidemiologic monitoring of plague infectious agent, and analysis of epidemics and outbreaks of plague with establishing the source of origin of the strain and routes of introduction of the infection.

The Role of Early-Phase Transmission in the Spread of Yersinia pestis

PubMed Central

EISEN, REBECCA J.; DENNIS, DAVID T.; GAGE, KENNETH L.

2015-01-01

Early-phase transmission (EPT) of Yersinia pestis by unblocked fleas is a well-documented, replicable phenomenon with poorly defined mechanisms. We review evidence demonstrating EPT and current knowledge on its biological and biomechanical processes. We discuss the importance of EPT in the epizootic spread of Y. pestis and its role in the maintenance of plague bacteria in nature. We further address the role of EPT in the epidemiology of plague. PMID:26336267

Ecology of Yersinia pestis and the Epidemiology of Plague.

PubMed

Dubyanskiy, Vladimir M; Yeszhanov, Aidyn B

2016-01-01

This chapter summarizes information about the natural foci of plague in the world. We describe the location, main hosts, and vectors of Yersinia pestis. The ecological features of the hosts and vectors of plague are listed, including predators - birds and mammals and their role in the epizootic. The epizootic process in plague and the factors affecting the dynamics of epizootic activity of natural foci of Y. pestis are described in detail. The mathematical models of the epizootic process in plague and predictive models are briefly described. The most comprehensive list of the hosts and vectors of Y. pestis in the world is presented as well.

Far East Scarlet-Like Fever Caused by a Few Related Genotypes of Yersinia pseudotuberculosis, Russia.

PubMed

Timchenko, Nelly F; Adgamov, Ruslan R; Popov, Alexander F; Psareva, Ekaterina K; Sobyanin, Konstantin A; Gintsburg, Alexander L; Ermolaeva, Svetlana A

2016-03-01

We used multivirulence locus sequence typing to analyze 68 Yersinia pseudotuberculosis isolates from patients in Russia during 1973-2014, including 41 isolates from patients with Far East scarlet-like fever. Four genotypes were found responsible, with 1 being especially prevalent. Evolutionary analysis suggests that epidemiologic advantages could cause this genotype's dominance.

Protocol for Detection of Yersinia pestis in Environmental ...

EPA Pesticide Factsheets

Methods Report This is the first ever open-access and detailed protocol available to all government departments and agencies, and their contractors to detect Yersinia pestis, the pathogen that causes plague, from multiple environmental sample types including water. Each analytical method includes sample processing procedure for each sample type in a step-by-step manner. It includes real-time PCR, traditional microbiological culture, and the Rapid Viability PCR (RV-PCR) analytical methods. For large volume water samples it also includes an ultra-filtration-based sample concentration procedure. Because of such a non-restrictive availability of this protocol to all government departments and agencies, and their contractors, the nation will now have increased laboratory capacity to analyze large number of samples during a wide-area plague incident.

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

Attenuated enzootic (pestoides) isolates of Yersinia pestis express active aspartase.

PubMed

Bearden, Scott W; Sexton, Christopher; Pare, Joshua; Fowler, Janet M; Arvidson, Cindy G; Yerman, Lyudmyla; Viola, Ronald E; Brubaker, Robert R

2009-01-01

It is established that Yersinia pestis, the causative agent of bubonic plague, recently evolved from enteropathogenic Yersinia pseudotuberculosis by undergoing chromosomal degeneration while acquiring two unique plasmids that facilitate tissue invasion (pPCP) and dissemination by fleabite (pMT). Thereafter, plague bacilli spread from central Asia to sylvatic foci throughout the world. These epidemic isolates exhibit a broad host range including man as opposed to enzootic (pestoides) variants that remain in ancient reservoirs where infection is limited to muroid rodents. Cells of Y. pseudotuberculosis are known to express glucose-6-phosphate dehydrogenase (Zwf) and aspartase (AspA); these activities are not detectable in epidemic Y. pestis due to missense mutations (substitution of proline for serine at amino position 155 of Zwf and leucine for valine at position 363 of AspA). In this study, functional Zwf was found in pestoides strains E, F and G but not seven other enzootic isolates; enzymic activity was associated with retention of serine at amino acid position 155. Essentially, full AspA activity occurred in pestoides isolates where valine (pestoides A, B, C and D) or serine (pestoides E, F, G and I) occupied position 363. Reduced activity occurred in strains Angola and A16, which contained phenylalanine at this position. The kcat but not Km of purified AspA from strain Angola was significantly reduced. In this context, aspA of the recently described attenuated enzootic microtus biovar encodes active valine at position 363, further indicating that functional AspA is a biomarker for avirulence of Y. pestis in man.

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

Far East Scarlet-Like Fever Caused by a Few Related Genotypes of Yersinia pseudotuberculosis, Russia

PubMed Central

Timchenko, Nelly F.; Adgamov, Ruslan R.; Popov, Alexander F.; Psareva, Ekaterina K.; Sobyanin, Konstantin A.; Gintsburg, Alexander L.

2016-01-01

We used multivirulence locus sequence typing to analyze 68 Yersinia pseudotuberculosis isolated in Russia during 1973–2014, including 41 isolates from patients with Far East scarlet-like fever. Four genotypes were found responsible, with 1 being especially prevalent. Evolutionary analysis suggests that epidemiologic advantages could cause this genotype’s dominance. PMID:26889961

Growth of a plasmid-bearing (pYV) Yersinia pestis KIM5 in retail raw ground pork

USDA-ARS?s Scientific Manuscript database

Yersinia pestis can cause oro-pharyngeal plague as a result of consumption or handling of meat from infected animals. Thus, food naturally or intentionally contaminated can have a role in the dissemination of human plague. The growth of a conditionally virulent plasmid (pYV)-bearing rifampicin-res...

Yersiniabactin iron uptake: mechanisms and role in Yersinia pestis pathogenesis

PubMed Central

Perry, Robert D.; Fetherston, Jacqueline D.

2011-01-01

Yersiniabactin (Ybt) is a siderophore-dependent iron uptake system encoded on a pathogenicity island that is widespread among pathogenic bacteria including the Yersiniae. While biosynthesis of the siderophore has been elucidated, the secretion mechanism and a few components of the uptake/utilization pathway are unidentified. ybt genes are transcriptionally repressed by Fur but activated by YbtA, likely in combination with the siderophore itself. The Ybt system is essential for the ability of Y. pestis to cause bubonic plague and important in pneumonic plague as well. However, the ability to cause fatal septicemic plague is independent of Ybt. PMID:21609780

Yersinia pestis Requires Host Rab1b for Survival in Macrophages

PubMed Central

Connor, Michael G.; Pulsifer, Amanda R.; Price, Christopher T.; Abu Kwaik, Yousef; Lawrenz, Matthew B.

2015-01-01

Yersinia pestis is a facultative intracellular pathogen that causes the disease known as plague. During infection of macrophages Y. pestis actively evades the normal phagosomal maturation pathway to establish a replicative niche within the cell. However, the mechanisms used by Y. pestis to subvert killing by the macrophage are unknown. Host Rab GTPases are central mediators of vesicular trafficking and are commonly targeted by bacterial pathogens to alter phagosome maturation and killing by macrophages. Here we demonstrate for the first time that host Rab1b is required for Y. pestis to effectively evade killing by macrophages. We also show that Rab1b is specifically recruited to the Yersinia containing vacuole (YCV) and that Y. pestis is unable to subvert YCV acidification when Rab1b expression is knocked down in macrophages. Furthermore, Rab1b knockdown also altered the frequency of association between the YCV with the lysosomal marker Lamp1, suggesting that Rab1b recruitment to the YCV directly inhibits phagosome maturation. Finally, we show that Rab1b knockdown also impacts the pH of the Legionella pneumophila containing vacuole, another pathogen that recruits Rab1b to its vacuole. Together these data identify a novel role for Rab1b in the subversion of phagosome maturation by intracellular pathogens and suggest that recruitment of Rab1b to the pathogen containing vacuole may be a conserved mechanism to control vacuole pH. PMID:26495854

Microbiome Composition and Diversity of the Ice-Dwelling Sea Anemone, Edwardsiella andrillae.

PubMed

Murray, Alison E; Rack, Frank R; Zook, Robert; Williams, Michael J M; Higham, Mary L; Broe, Michael; Kaufmann, Ronald S; Daly, Marymegan

2016-10-01

Edwardsiella andrillae is a sea anemone (Cnidaria: Anthozoa: Actiniaria) only known to live embedded in the ice at the seawater interface on the underside of the Ross Ice Shelf, Antarctica. Although the anatomy and morphological characteristics of E. andrillae have been described, the adaptations of this species to the under-ice ecosystem have yet to be examined. One feature that may be important to the physiology and ecology of E. andrillae is its microbiome, which may play a role in health and survival, as has been deduced in other metazoans, including anthozoans. Here we describe the microbiome of five specimens of E. andrillae, compare the diversity we recovered to that known for temperate anemones and another Antarctic cnidarian, and consider the phylogenetic and functional implications of microbial diversity for these animals. The E. andrillae microbiome was relatively low in diversity, with seven phyla detected, yet included substantial phylogenetic novelty. Among the five anemones investigated, the distribution of microbial taxa varied; this trait appears to be shared by many anthozoans. Most importantly, specimens either appeared to be dominated by Proteobacteria-affiliated members or by deeply branching Tenericute sequences. There were few closely related sequence types that were common to temperate and Antarctic sea anemone microbiomes, the exception being an Acinetobacter-related representative. Similar observations were made between microbes associated with E. andrillae and an Antarctic soft coral; however, there were several closely-related, low abundance Gammaproteobacteria in both Antarctic microbiomes, particularly from the soft coral, that are also commonly detected in Southern Ocean seawater. Although this preliminary study leaves open many questions concerning microbiome diversity and its role in host ecology, we identify major lineages of microbes (e.g., diverse deep-branching Alphaproteobacteria, Epsilonproteobacteria, and divergent

Yersinia enterocolitica in fermented sausages

NASA Astrophysics Data System (ADS)

Mitrović, R.; Janković, V.; Baltić, B.; Ivanović, J.

2017-09-01

Different types of food, among them meat, can be the cause of food-borne diseases, and infections are commonly caused by Campylobacter, Salmonella, Yersinia enterocolitica, verotoxic Escherichia coli and Listeria monocytogenes. All these bacteria, depending on a number of factors, including animal species, geographical origin, climatic factors, methods of animal breeding and meat production, could cause disease. Here, we summarise results on production of different groups of sausages produced with or without added starter culture, and contaminated with Y.enterocolitica (control sausages were not contaminated). During the ripening, changes in the microbiological status of the fermented sausages and their physical and chemical properties were monitored. For all tests, standard methods were used. In these fermented sausages, the number of Y. enterocolitica decreased during ripening. The number of Y. enterocolitica was statistically significantly lower in sausages with added starter culture on all days of the study Zoonotic pathogens in meat should be controlled through the complete production chain, from the farms to consumers, in order to reduce the probability of disease in humans. However, the necessary controls in the production chain are not the same for all bacteria.

Inactivation of avirulent Yersinia pestis on food and food contact surfaces by ultraviolet light and freezing

USDA-ARS?s Scientific Manuscript database

Yersinia pestis, the causative agent of plague, can occasionally be contracted as a naso-pharangeal or gastrointestinal illness through consumption of contaminated meat. In this study, the use of 254 nm ultraviolet light (UV-C) to inactivate a multi-isolate cocktail of avirulent Y. pestis on food an...

Simultaneous and Rapid Detection of Salmonella typhi, Bacillus anthracis, and Yersinia pestis by Using Multiplex Polymerase Chain Reaction (PCR)

PubMed Central

Safari Foroshani, Nargess; Karami, Ali; Pourali, Fatemeh

2013-01-01

Background Salmonella typhi, Bacillus anthracis, and Yersinia pestis are some serious human pathogens, which their early diagnosis is of great importance. Salmonella typhi, Bacillus anthracis, and Yersinia pestis cause typhoid fever, anthrax, and plague respectively. These bacteria can be used to make biologic weapons. Objectives In this study, we designed a new and rapid diagnostic method based on Uniplex and Multiplex PCR method. Materials and Methods Uniplex and multiplex Polymerase Chain Reaction (PCR) were conducted on virulent genes of hp and invA of Salmonella typhimurium, Pa and chr of Bacillus anthracis, and pla of Yersinia pestis. A genome from other bacteria was used to study the specificity of the primer and the PCR test. Results Standard strains used in this study showed that primers were specific. As for sensitivity, it was shown that this method can diagnose 1-10 copies of the genome, or 1-10 Colony Forming Units (CFU) for each of the bacteria. All pieces except anthrax were sequenced in PCR to validate the product. DNA fragment resulted from Bacillus anthracis was confirmed by restriction enzyme digestions. Conclusion The designed methods are accurate, rapid, and inexpensive to find and differentiate these bacteria from similar bacteria. They can be applied for rapid diagnosis of these agents in different specimens, and bioterrorism cases. PMID:24719692

Epidemiological study of Yersinia enterocolitica in swine herds in Québec.

PubMed Central

Pilon, J; Higgins, R; Quessy, S

2000-01-01

The objectives of this study were the identification of the different contamination sources of Yersinia enterocolitica, as well as the determination of the prevalence and the distribution of the different genotypes in swine herds. The owners of 20 farms, located in the Richelieu-Yamaska region, agreed to participate in the study. Each farm was visited a minimum of 5 times between May and October 1997, and, at each visit, 20 environmental and 10 fecal samples were collected. Yersinia enterocolitica isolates were identified, serotyped, and submitted to a genetic characterization by pulsed-field gel electrophoresis. The correlation coefficient (0.61) between prevalence in environment and in feces was significant (P = 0.004). Among the 153 positive samples, 93.5% belonged to serotype 0:3. The comparison of PFGE profiles revealed that all environmental Y. enterocolitica isolates had a profile identical to that of isolates recovered in feces from the corresponding farms. Also, when the genetic profiles of isolates recovered from feces collected at the first visit were compared with the profiles of isolates obtained from the subsequent visits, the same profile was observed on every farm. We concluded that environment does not represent the main source of contamination of swine by Y. enterocolitica and that, in most instances, the same strain persists in a barn from one production lot to another. Images Figure 1. Figure 2. PMID:10816831

[Susceptibility to azithromycin and other antibiotics in recent isolates of Salmonella, Shigella and Yersinia].

PubMed

Martín-Pozo, Angeles; Arana, David M; Fuentes, Miriam; Alós, Juan-Ignacio

2014-01-01

Azithromycin represents an alternative option to treat bacterial diarrhea when the antibiotic therapy is indicated. Little is known regarding the susceptibility to azithromycin in enteropathogens in Spain. The MICs of azithromycin were determined by E-test against Salmonella non-typhi (SNT), Shigella and Yersinia isolates collected over the last three years (2010-2012). In addition, the susceptibility to other antibiotics usually used to treat gastrointestinal diseases was determined in these isolates by using a microdilution method. A total of 139 strains of SNT, Shigella and Yersinia were studied. All of them, except one strain, had a MIC≤16mg/L of azithromycin. In the adult population, 14.7% and 40.6% of SNT and Shigella isolates, respectively, were resistant to at least 2 of following antibiotics: amoxicillin, trimethoprim-sulfamethoxazole and ciprofloxacin. In the pediatric population, 10% of SNT clinical isolates and 28.6% (2/7) of Shigella isolates were resistant to amoxicillin and trimethoprim-sulfamethoxazole. In our experience, azithromycin would be a useful antibiotic alternative to treat bacterial diarrhea. Copyright © 2013 Elsevier España, S.L. y Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

Pneumonic Plague: The Darker Side of Yersinia pestis.

PubMed

Pechous, Roger D; Sivaraman, Vijay; Stasulli, Nikolas M; Goldman, William E

2016-03-01

Inhalation of the bacterium Yersinia pestis results in primary pneumonic plague. Pneumonic plague is the most severe manifestation of plague, with mortality rates approaching 100% in the absence of treatment. Its rapid disease progression, lethality, and ability to be transmitted via aerosol have compounded fears of the intentional release of Y. pestis as a biological weapon. Importantly, recent epidemics of plague have highlighted a significant role for pneumonic plague during outbreaks of Y. pestis infections. In this review we describe the characteristics of pneumonic plague, focusing on its disease progression and pathogenesis. The rapid time-course, severity, and difficulty of treating pneumonic plague highlight how differences in the route of disease transmission can enhance the lethality of an already deadly pathogen. Copyright © 2015 Elsevier Ltd. All rights reserved.

Three-dimensional structures of unligated uridine phosphorylase from Yersinia pseudotuberculosis at 1.4 Å resolution and its complex with an antibacterial drug

NASA Astrophysics Data System (ADS)

Balaev, V. V.; Lashkov, A. A.; Gabdulkhakov, A. G.; Dontsova, M. V.; Mironov, A. S.; Betzel, C.; Mikhailov, A. M.

2015-07-01

Uridine phosphorylases play an essential role in the cellular metabolism of some antibacterial agents. Acute infectious diseases (bubonic plague, yersiniosis, pseudotuberculosis, etc., caused by bacteria of the genus Yersinia) are treated using both sulfanilamide medicines and antibiotics, including trimethoprim. The action of an antibiotic on a bacterial cell is determined primarily by the character of its interactions with cellular components, including those which are not targets (for example, with pyrimidine phosphorylases). This type of interaction should be taken into account in designing drugs. The three-dimensional structure of uridine phosphorylase from the bacterium Yersinia pseudotuberculosis ( YptUPh) with the free active site was determined for the first time by X-ray crystallography and refined at 1.40 Å resolution (DPI = 0.062 Å; ID PDB: 4OF4). The structure of the complex of YptUPh with the bacteriostatic drug trimethoprim was studied by molecular docking and molecular dynamics methods. The trimethoprim molecule was shown to be buffered by the enzyme YptUPh, resulting in a decrease in the efficiency of the treatment of infectious diseases caused by bacteria of the genus Yersinia with trimethoprim.

Synergies between vaccination and dietary arginine and glutamine supplementation improve the immune response of channel catfish against Edwardsiella ictaluri.

PubMed

Pohlenz, Camilo; Buentello, Alejandro; Criscitiello, Michael F; Mwangi, Waithaka; Smith, Roger; Gatlin, Delbert M

2012-09-01

Channel catfish was used to investigate the enhancement of vaccine efficacy following dietary supplementation with arginine (ARG, 4% of diet), glutamine (GLN, 2% of diet), or a combination of both. After vaccination against Edwardsiella ictaluri, humoral and cellular immune responses, along with lymphoid organ responses were evaluated. E. ictaluri-specific antibody titers in plasma were higher (P < 0.05) in fish fed the supplemented diets compared to those fed the basal diet as early as 7 d post-vaccination (dpv). B-cell proportion in head-kidney was higher (P < 0.05) at 14 dpv in vaccinated fish fed the GLN diet. The responsiveness of spleen and head-kidney lymphocytes against E. ictaluri was enhanced (P < 0.05) by dietary supplementation of ARG or GLN at 14 dpv. Additionally, at 7 dpv, vaccinated fish fed the GLN diet had higher (P < 0.05) head kidney weights relative to the other dietary treatments, and vaccinated fish fed ARG-supplemented diets had higher (P < 0.05) protein content in this tissue. Results from this study suggest that dietary supplementation of ARG and GLN may improve specific cellular and humoral mechanisms, enhancing the acquired immunity in vaccinated channel catfish. Copyright © 2012 Elsevier Ltd. All rights reserved.

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...

The Effects of Low-Shear Mechanical Stress on Yersinia pestis Virulence

NASA Astrophysics Data System (ADS)

Lawal, Abidat; Jejelowo, Olufisayo A.; Rosenzweig, Jason A.

2010-11-01

Manned space exploration has created a need to evaluate the effects of spacelike stress on pathogenic and opportunistic microbes astronauts could carry with them to the International Space Station and beyond. Yersinia pestis (YP) causes bubonic, septicemic, and pneumonic plague and is capable of killing infected patients within 3-7 days. In this study, low-shear modeled microgravity (LSMMG), a spacelike stress, was used to physically stress YP; and its effects on proliferation, cold growth, and type III secretion system (T3SS) function were evaluated. YP was grown to saturation in either LSMMG or normal gravity (NG) conditions prior to being used for RAW 246.7 cell infections, HeLa cell infections, and Yop secretion assays. A mutant strain of YP (ΔyopB) that lacks the ability to inject Yersinia outer membrane proteins (Yops) into the host cell was used as a negative control in cell infection experiments. Our experimental results indicate that YP cultivated under LSMMG resulted in reduced YopM production and secretion compared to its NG-grown counterpart. Similarly, NG-grown YP induced more cell rounding in HeLa cells than did the LSMMG-grown YP, which suggests that LSMMG somehow impairs T3SS optimum function. Also, LSMMG-grown YP used to infect cultured RAW 246.7 cells showed a similar pattern of dysfunction in that it proliferated less than did its NG-grown counterpart during an 8-hour infection period. This study suggests that LSMMG can attenuate bacterial virulence contrary to previously published data that have demonstrated LSMMG-induced hypervirulence of other Gram-negative enterics.

The effects of low-shear mechanical stress on Yersinia pestis virulence.

PubMed

Lawal, Abidat; Jejelowo, Olufisayo A; Rosenzweig, Jason A

2010-11-01

Manned space exploration has created a need to evaluate the effects of spacelike stress on pathogenic and opportunistic microbes astronauts could carry with them to the International Space Station and beyond. Yersinia pestis (YP) causes bubonic, septicemic, and pneumonic plague and is capable of killing infected patients within 3-7 days. In this study, low-shear modeled microgravity (LSMMG), a spacelike stress, was used to physically stress YP; and its effects on proliferation, cold growth, and type III secretion system (T3SS) function were evaluated. YP was grown to saturation in either LSMMG or normal gravity (NG) conditions prior to being used for RAW 246.7 cell infections, HeLa cell infections, and Yop secretion assays. A mutant strain of YP (ΔyopB) that lacks the ability to inject Yersinia outer membrane proteins (Yops) into the host cell was used as a negative control in cell infection experiments. Our experimental results indicate that YP cultivated under LSMMG resulted in reduced YopM production and secretion compared to its NG-grown counterpart. Similarly, NG-grown YP induced more cell rounding in HeLa cells than did the LSMMG-grown YP, which suggests that LSMMG somehow impairs T3SS optimum function. Also, LSMMG-grown YP used to infect cultured RAW 246.7 cells showed a similar pattern of dysfunction in that it proliferated less than did its NG-grown counterpart during an 8-hour infection period. This study suggests that LSMMG can attenuate bacterial virulence contrary to previously published data that have demonstrated LSMMG-induced hypervirulence of other Gram-negative enterics.

Viral and bacterial septicaemic infections modulate the expression of PACAP splicing variants and VIP/PACAP receptors in brown trout immune organs.

PubMed

Gorgoglione, Bartolomeo; Carpio, Yamila; Secombes, Christopher J; Taylor, Nick G H; Lugo, Juana María; Estrada, Mario Pablo

2015-12-01

Pituitary Adenylate Cyclase-Activating Polypeptide (PACAP) and PACAP-Related Peptide (PRP) are structurally similar peptides encoded in the same transcripts. Their transcription has been detected not only in the brain but also in a wide range of peripheral tissues, even including organs of the immune system. PACAP exerts pleiotropic activities through G-protein coupled membrane receptors: the PACAP-specific PAC-1 and the VPAC-1 and VPAC-2 receptors that exhibit similar affinities for the Vasoactive Intestinal Peptide (VIP) and PACAP. Recent findings added PACAP and its receptors to the growing list of mediators that allow cross-talk between the nervous, endocrine and immune systems in fish. In this study the expression of genes encoding for PACAP and PRP, as well as VIP/PACAP receptors was studied in laboratory-reared brown trout (Salmo trutta) after septicaemic infections. Respectively Viral Haemorrhagic Septicaemia Virus (VHSV-Ia) or the Gram-negative bacterium Yersinia ruckeri (ser. O1 - biot. 2) were used in infection challenges. Kidney and spleen, the teleost main lymphopoietic organs, were sampled during the first two weeks post-infection. RT-qPCR analysis assessed specific pathogens burden and gene expression levels. PACAP and PRP transcription in each organ was positively correlated to the respective pathogen burden, assessed targeting the VHSV-glycoprotein or Y. ruckeri 16S rRNA. Results showed as the transcription of PACAP splicing variants and VIP/PACAP receptors is modulated in these organs during an acute viral and bacterial septicaemic infections in brown trout. These gene expression results provide clues as to how the PACAP system is modulated in fish, confirming an involvement during active immune responses elicited by both viral and bacterial aetiological agents. However, further experimental evidence is still required to fully elucidate and characterize the role of PACAP and PRP for an efficient immune response against pathogens. Copyright © 2015

A procedure for maintenance of the virulence plasmid (pYV) in Yersinia pestis under culture conditions

USDA-ARS?s Scientific Manuscript database

The pathogenicity of Yersinia pestis depends on the presence of a virulence plasmid (pYV). The unstable nature of pYV in Y. pestis leads to the eventual outgrowth of pYV less cells due to its higher growth rate. Thus, it was necessary to develop procedures to monitor the presence of the plasmid du...

Development of In Vitro Correlate Assays of Immunity to Infection with Yersinia Pestis

DTIC Science & Technology

2007-05-01

cynomolgus macaques (CM) and African green (Chlorocebus aethiops) monkeys (AGM) vaccinated s.c. three times at 4-week intervals with the F1-V fusion...Yersinia pestis in African green monkeys . Arch. Pathol. Lab. Med. 120:156–163. 15. Faure, K., J. Fujimoto, D. W. Shimabukuro, T. Ajayi, N. Shime, K...A. Kuwae, C. Sasakawa, and S. Imajoh-Ohmi. 1999. Shigella flexneri YSH6000 induces two types of cell death, apoptosis and oncosis, in the

JAK and STAT members in channel catfish: Identification, phylogenetic analysis and expression profiling after Edwardsiella ictaluri infection.

PubMed

Jin, Yulin; Zhou, Tao; Li, Ning; Liu, Shikai; Xu, Xiaoyan; Pan, Ying; Tan, Suxu; Shi, Huitong; Yang, Yujia; Yuan, Zihao; Wang, Wenwen; Luo, Jian; Gao, Dongya; Dunham, Rex; Liu, Zhanjiang

2018-04-01

The Janus kinase/signal transducers and activators of transcription (JAK/STAT) signaling pathway is one of the main pleiotropic cascades used to transmit information from extracellular receptors to the nucleus, which results in DNA transcription and expression of genes involved in immunity, proliferation, differentiation, migration, apoptosis, and cell survival. Members of JAK family and STAT family have been extensively studied in different mammalian species because of their important roles in innate and adaptive immune responses. However, they have not been systematically studied among teleost fish species. In this study, five JAK family members and eight STAT family members were identified and characterized from channel catfish. Phylogenetic analysis was conducted to properly annotate these genes. Syntenic analysis was also conducted to establish orthology, and confirm the results from phylogenetic analysis. Compared to mammals, more members of the JAK and STAT family were identified in channel catfish genome. Expression of JAK and STAT family members was detected in healthy catfish tissues, but was induced in gill, liver, and intestine after bacterial challenge. Notably, the significant upregulation of STAT1b gene in catfish liver, gill and intestine after Edwardsiella ictaluri infection supported the notion that high STAT1 expression are involved in defense against pathogens. Collectively, the increased expression of JAK and STAT members in tested tissues suggested their crucial function in defending the host against pathogen invasion. Copyright © 2017 Elsevier Ltd. All rights reserved.

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.

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...

LcrV Mutants That Abolish Yersinia Type III Injectisome Function

PubMed Central

Ligtenberg, Katherine Given; Miller, Nathan C.; Mitchell, Anthony; Plano, Gregory V.

2013-01-01

LcrV, the type III needle cap protein of pathogenic Yersinia, has been proposed to function as a tether between YscF, the needle protein, and YopB-YopD to constitute the injectisome, a conduit for the translocation of effector proteins into host cells. Further, insertion of LcrV-capped needles from a calcium-rich environment into host cells may trigger the low-calcium signal for effector translocation. Here, we used a genetic approach to test the hypothesis that the needle cap responds to the low-calcium signal by promoting injectisome assembly. Growth restriction of Yersinia pestis in the absence of calcium (low-calcium response [LCR+] phenotype) was exploited to isolate dominant negative lcrV alleles with missense mutations in its amber stop codon (lcrV*327). The addition of at least four amino acids or the eight-residue Strep tag to the C terminus was sufficient to generate an LCR− phenotype, with variant LcrV capping type III needles that cannot assemble the YopD injectisome component. The C-terminal Strep tag appears buried within the cap structure, blocking effector transport even in Y. pestis yscF variants that are otherwise calcium blind, a constitutive type III secretion phenotype. Thus, LcrV*327 mutants arrest the needle cap in a state in which it cannot respond to the low-calcium signal with either injectisome assembly or the activation of type III secretion. Insertion of the Strep tag at other positions of LcrV produced variants with wild-type LCR+, LCR−, or dominant negative LCR− phenotypes, thereby allowing us to identify discrete sites within LcrV as essential for its attributes as a secretion substrate, needle cap, and injectisome assembly factor. PMID:23222719

Investigating the ?Trojan Horse? Mechanism of Yersinia pestis Virulence

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

McCutchen-Maloney, S L; Fitch, J P

2005-02-08

Yersinia pestis, the etiological agent of plague, is a Gram-negative, highly communicable, enteric bacterium that has been responsible for three historic plague pandemics. Currently, several thousand cases of plague are reported worldwide annually, and Y. pestis remains a considerable threat from a biodefense perspective. Y. pestis infection can manifest in three forms: bubonic, septicemic, and pneumonic plague. Of these three forms, pneumonic plague has the highest fatality rate ({approx}100% if left untreated), the shortest intervention time ({approx}24 hours), and is highly contagious. Currently, there are no rapid, widely available vaccines for plague and though plague may be treated with antibiotics,more » the emergence of both naturally occurring and potentially engineered antibiotic resistant strains makes the search for more effective therapies and vaccines for plague of pressing concern. The virulence mechanism of this deadly bacterium involves induction of a Type III secretion system, a syringe-like apparatus that facilitates the injection of virulence factors, termed Yersinia outer membrane proteins (Yops), into the host cell. These virulence factors inhibit phagocytosis and cytokine secretion, and trigger apoptosis of the host cell. Y. pestis virulence factors and the Type III secretion system are induced thermally, when the bacterium enters the mammalian host from the flea vector, and through host cell contact (or conditions of low Ca{sup 2+} in vitro). Apart from the temperature increase from 26 C to 37 C and host cell contact (or low Ca{sup 2+} conditions), other molecular mechanisms that influence virulence induction in Y. pestis are largely uncharacterized. This project focused on characterizing two novel mechanisms that regulate virulence factor induction in Y. pestis, immunoglobulin G (IgG) binding and quorum sensing, using a real-time reporter system to monitor induction of virulence. Incorporating a better understanding of the mechanisms of

[Yersinia pestis and plague - an update].

PubMed

Stock, Ingo

2014-12-01

The plague of man is a severe, systemic bacterial infectious disease. Without antibacterial therapy, the disease is associated with a high case fatality rate, ranging from 40% (bubonic plague) to nearly 100% (septicemic and pneumonic plague). The disease is caused by Yersinia pestis, a non-motile, gram-negative, facultative anaerobic bacterium belonging to the family of Enterobacteriaceae. In nature, Y. pestis has been found in several rodent species and some other small animals such as shrews. Within its reservoir host, Y. pestis circulates via flea bites. Transmission of Y. pestis to humans occurs by the bite of rat fleas, other flea vectors or by non vectorial routes, e. g., handling infected animals or consumption of contaminated food. Human-to-human transmission of the pathogen occurs primarily through aerosol droplets. Compared to the days when plague was a pandemic scourge, the disease is now relatively rare and limited to some rural areas of Africa. During the last ten years, however, plague outbreaks have been registered repea- tedly in some African regions. For treatment of plague, streptomycin is still considered the drug of choice. Chloramphenicol, doxycycline, gentamicin and ciprofloxacin are also promising drugs. Recombinant vaccines against plague are in clinical development.

Misidentification of Yersinia pestis by automated systems, resulting in delayed diagnoses of human plague infections--Oregon and New Mexico, 2010-2011.

PubMed

Tourdjman, Mathieu; Ibraheem, Mam; Brett, Meghan; Debess, Emilio; Progulske, Barbara; Ettestad, Paul; McGivern, Teresa; Petersen, Jeannine; Mead, Paul

2012-10-01

One human plague case was reported in Oregon in September 2010 and another in New Mexico in May 2011. Misidentification of Yersinia pestis by automated identification systems contributed to delayed diagnoses for both cases.

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.

Use of bioluminescence mutant screening for identification of Edwardsiella ictaluri genes involved in channel catfish (Ictalurus punctatus) skin colonization.

PubMed

Menanteau-Ledouble, Simon; Lawrence, Mark L

2013-03-23

Initial invasion of the host is the first and vital part of any infection process. We have demonstrated that Edwardsiella ictaluri is capable of colonizing and penetrating catfish skin. Therefore, a mutant library was constructed by random insertion of the Mar2xT7 transposon into the chromosome of E. ictaluri harboring the bioluminescence plasmid pAKgfplux1. This library was then screened through a series of three consecutive challenges for mutants showing a decreased ability to colonize the catfish epithelium. Eighteen mutants were identified that have decreased adhesion and virulence. Mutated genes encoded one sensor protein, two transport proteins, five enzymes, two regulatory proteins, and five hypothetical proteins. Among the mutated genes, the first one identified was a gene encoding for RstA/B, which is known to play a role in regulating the expression of invasion genes in Salmonella enterica Typhimurium. Another mutant was lacking a putative ribonuclease similar to a Shigella protein that regulates the expression of adhesin. A third mutant was defective in a protein similar to a Brucella protein that was initially identified as a transporter, but actually is a member of a newly discovered adhesin family. Results from this study could enable development of a new strategy for blocking E. ictaluri invasion at the initial adherence stage. Copyright © 2012 Elsevier B.V. All rights reserved.

Evaluation of Commercial Off-the-Shelf Solutions for Supporting Viability Retention of Yersinia Pestis Cells

DTIC Science & Technology

2017-11-01

either trade or manufacturers ’ names in this report does not constitute an official endorsement of any commercial products. The report may not be cited...were not the result of residual environmental contamination . Major threat agents such as Bacillus anthracis, Yersinia pestis, and Burkholderia...presence of Y. pestis and B. anthracis, even though no deliberate contamination was verified (Afshinnekoo et al., 2015). In fact, as of 2015, there have

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.

The NLRP12 inflammasome recognizes Yersinia pestis

PubMed Central

Vladimer, Gregory I.; Weng, Dan; Paquette, Sara W. Montminy; Vanaja, Sivapriya Kailasan; Rathinam, Vijay A. K.; Aune, Marie Hjelmseth; Conlon, Joseph E.; Burbage, Joseph J.; Proulx, Megan K.; Liu, Qin; Reed, George; Mecsas, Joan C.; Iwakura, Yoichiro; Bertin, John; Goguen, Jon D.; Fitzgerald, Katherine A.; Lien, Egil

2013-01-01

Summary Yersinia pestis, the causative agent of plague, is able to suppress production of inflammatory cytokines IL-18 and IL-1β, which are generated through caspase-1–activating nucleotide-binding domain and leucine-rich repeat (NLR)-containing inflammasomes. Here, we sought to elucidate the role of NLRs and IL-18 during plague. Lack of IL-18 signaling led to increased susceptibility to Y. pestis, producing tetra-acylated lipid A,and an attenuated strain producing a Y. pseudotuberculosis-like hexa-acylated lipid A. We found that the NLRP12 inflammasome was an important regulator controlling IL-18 and IL-1β production after Y. pestis infection, and NLRP12-deficient mice were more susceptible to bacterial challenge. NLRP12 also directed interferon-γ production via induction of IL-18, but had minimal effect on signaling to the transcription factor NF-κB._ These studies reveal a role for NLRP12 in host resistance against pathogens. Minimizing NLRP12 inflammasome activation may have been a central factor in evolution of the high virulence of Y. pestis. PMID:22840842

Interaction of the Disordered Yersinia Effector Protein YopE with Its Cognate Chaperone SycE

DTIC Science & Technology

2009-01-01

structures of YopECBD were molten globules with a hydrophobic core. Molecular dynamics (MD) simulations indi- cated that the structure remained compact at...ensembles of unfolded conformations of the Yersinia effector YopE using REMD simulations and docked them to the chaper- one SycE using a multistep protein...disordered state but transitions into an ordered state upon binding to its cognate chaperone (7). The dynamics of the disordered effector protein and

Braun lipoprotein (Lpp) contributes to virulence of yersiniae: potential role of Lpp in inducing bubonic and pneumonic plague.

PubMed

Sha, Jian; Agar, Stacy L; Baze, Wallace B; Olano, Juan P; Fadl, Amin A; Erova, Tatiana E; Wang, Shaofei; Foltz, Sheri M; Suarez, Giovanni; Motin, Vladimir L; Chauhan, Sadhana; Klimpel, Gary R; Peterson, Johnny W; Chopra, Ashok K

2008-04-01

Yersinia pestis evolved from Y. pseudotuberculosis to become the causative agent of bubonic and pneumonic plague. We identified a homolog of the Salmonella enterica serovar Typhimurium lipoprotein (lpp) gene in Yersinia species and prepared lpp gene deletion mutants of Y. pseudotuberculosis YPIII, Y. pestis KIM/D27 (pigmentation locus minus), and Y. pestis CO92 with reduced virulence. Mice injected via the intraperitoneal route with 5 x 10(7) CFU of the Deltalpp KIM/D27 mutant survived a month, even though this would have constituted a lethal dose for the parental KIM/D27 strain. Subsequently, these Deltalpp KIM/D27-injected mice were solidly protected against an intranasally administered, highly virulent Y. pestis CO92 strain when it was given as five 50% lethal doses (LD(50)). In a parallel study with the pneumonic plague mouse model, after 72 h postinfection, the lungs of animals infected with wild-type (WT) Y. pestis CO92 and given a subinhibitory dose of levofloxacin had acute inflammation, edema, and masses of bacteria, while the lung tissue appeared essentially normal in mice inoculated with the Deltalpp mutant of CO92 and given the same dose of levofloxacin. Importantly, while WT Y. pestis CO92 could be detected in the bloodstreams and spleens of infected mice at 72 h postinfection, the Deltalpp mutant of CO92 could not be detected in those organs. Furthermore, the levels of cytokines/chemokines detected in the sera were significantly lower in animals infected with the Deltalpp mutant than in those infected with WT CO92. Additionally, the Deltalpp mutant was more rapidly killed by macrophages than was the WT CO92 strain. These data provided evidence that the Deltalpp mutants of yersiniae were significantly attenuated and could be useful tools in the development of new vaccines.

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.

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.

Effect of fat in ground beef on the growth and virulence plasmid (pYV) stability in Yersinia pestis

USDA-ARS?s Scientific Manuscript database

Knowledge of the behavior of Yersinia pestis in food may be useful in the event Y. pestis is used in a bioterrorism attack on the food supply. However, there are no reports on the growth of plasmid-bearing (pYV) virulent Y. pestis in food. The growth of a conditionally virulent pYV-bearing Yersini...

A procedure for monitoring the presence of the virulence plasmid (pYV) in Yersinia pestis under culture conditions

USDA-ARS?s Scientific Manuscript database

The pathogenicity of Yersinia pestis depends on the presence of a virulence plasmid (pYV). The unstable nature of pYV in Y. pestis leads to the eventual outgrowth of pYV less cells due its higher growth rate. Thus, it was necessary to develop procedures to monitor the presence of the plasmid durin...

Developing live vaccines against Yersinia pestis

PubMed Central

Sun, Wei; Roland, Kenneth L.; Curtiss, Roy

2014-01-01

Three great plague pandemics caused by the gram-negative bacterium Yersinia pestis have killed nearly 200 million people and it has been linked to biowarfare in the past. Plague is endemic in many parts of the world. In addition, the risk of plague as a bioweapon has prompted increased research to develop plague vaccines against this disease. Injectable subunit vaccines are being developed in the United States and United Kingdom. However, the live attenuated Y. pestis-EV NIIEG strain has been used as a vaccine for more than 70 years in the former Soviet Union and in some parts of Asia and provides a high degree of efficacy against plague. This vaccine has not gained general acceptance because of safety concerns. In recent years, modern molecular biological techniques have been applied to Y. pestis to construct strains with specific defined mutations designed to create safe, immunogenic vaccines with potential for use in humans and as bait vaccines to reduce the load of Y. pestis in the environment. In addition, a number of live, vectored vaccines have been reported using attenuated viral vectors or attenuated Salmonella strains to deliver plague antigens. Here we summarize the progress of live attenuated vaccines against plague. PMID:21918302

Humoral immune response against lipopolysaccharide and cytoplasmic proteins of Brucella abortus in cattle vaccinated with B. abortus S19 or experimentally infected with Yersinia enterocolitica serotype 0:9.

PubMed Central

Baldi, P C; Giambartolomei, G H; Goldbaum, F A; Abdón, L F; Velikovsky, C A; Kittelberger, R; Fossati, C A

1996-01-01

The humoral immune responses against three different antigens of Brucella abortus were monitored by enzyme-linked immunosorbent assay in cattle vaccinated with B. abortus S19 or experimentally infected with Yersinia enterocolitica serotype 0:9. Immunoglobulin G (IgG) and IgM responses against (i) B. abortus lipopolysaccharide (LPS), (ii) total cytoplasmic proteins depleted of LPS (LPS-free CYT), and (iii) B. abortus 18-kDa cytoplasmic protein were measured. Vaccinated animals and Yersinia-infected animals developed high anti-LPS IgM and IgG titers, which overlapped with those obtained with sera from B. abortus 544-infected animals used as positive controls. In contrast, only a slight or negative IgG and IgM response against LPS-free CYT and the 18-kDa protein was detected in vaccinated or Yersinia-infected cattle, although its levels were always significantly lower than those of B. abortus 544-infected animals. These data indicate that cytoplasmic proteins of B. abortus could be useful for the differential diagnosis of bovine brucellosis. PMID:8807216

Defective Innate Cell Response and Lymph Node Infiltration Specify Yersinia pestis Infection

PubMed Central

Guinet, Françoise; Avé, Patrick; Jones, Louis; Huerre, Michel; Carniel, Elisabeth

2008-01-01

Since its recent emergence from the enteropathogen Yersinia pseudotuberculosis, Y. pestis, the plague agent, has acquired an intradermal (id) route of entry and an extreme virulence. To identify pathophysiological events associated with the Y. pestis high degree of pathogenicity, we compared disease progression and evolution in mice after id inoculation of the two Yersinia species. Mortality studies showed that the id portal was not in itself sufficient to provide Y. pseudotuberculosis with the high virulence power of its descendant. Surprisingly, Y. pseudotuberculosis multiplied even more efficiently than Y. pestis in the dermis, and generated comparable histological lesions. Likewise, Y. pseudotuberculosis translocated to the draining lymph node (DLN) and similar numbers of the two bacterial species were found at 24 h post infection (pi) in this organ. However, on day 2 pi, bacterial loads were higher in Y. pestis-infected than in Y. pseudotuberculosis-infected DLNs. Clustering and multiple correspondence analyses showed that the DLN pathologies induced by the two species were statistically significantly different and identified the most discriminating elementary lesions. Y. pseudotuberculosis infection was accompanied by abscess-type polymorphonuclear cell infiltrates containing the infection, while Y. pestis-infected DLNs exhibited an altered tissue density and a vascular congestion, and were typified by an invasion of the tissue by free floating bacteria. Therefore, Y. pestis exceptional virulence is not due to its recently acquired portal of entry into the host, but is associated with a distinct ability to massively infiltrate the DLN, without inducing in this organ an organized polymorphonuclear cell reaction. These results shed light on pathophysiological processes that draw the line between a virulent and a hypervirulent pathogen. PMID:18301765

Defective innate cell response and lymph node infiltration specify Yersinia pestis infection.

PubMed

Guinet, Françoise; Avé, Patrick; Jones, Louis; Huerre, Michel; Carniel, Elisabeth

2008-02-27

Since its recent emergence from the enteropathogen Yersinia pseudotuberculosis, Y. pestis, the plague agent, has acquired an intradermal (id) route of entry and an extreme virulence. To identify pathophysiological events associated with the Y. pestis high degree of pathogenicity, we compared disease progression and evolution in mice after id inoculation of the two Yersinia species. Mortality studies showed that the id portal was not in itself sufficient to provide Y. pseudotuberculosis with the high virulence power of its descendant. Surprisingly, Y. pseudotuberculosis multiplied even more efficiently than Y. pestis in the dermis, and generated comparable histological lesions. Likewise, Y. pseudotuberculosis translocated to the draining lymph node (DLN) and similar numbers of the two bacterial species were found at 24 h post infection (pi) in this organ. However, on day 2 pi, bacterial loads were higher in Y. pestis-infected than in Y. pseudotuberculosis-infected DLNs. Clustering and multiple correspondence analyses showed that the DLN pathologies induced by the two species were statistically significantly different and identified the most discriminating elementary lesions. Y. pseudotuberculosis infection was accompanied by abscess-type polymorphonuclear cell infiltrates containing the infection, while Y. pestis-infected DLNs exhibited an altered tissue density and a vascular congestion, and were typified by an invasion of the tissue by free floating bacteria. Therefore, Y. pestis exceptional virulence is not due to its recently acquired portal of entry into the host, but is associated with a distinct ability to massively infiltrate the DLN, without inducing in this organ an organized polymorphonuclear cell reaction. These results shed light on pathophysiological processes that draw the line between a virulent and a hypervirulent pathogen.

Resistance of Mice of the 129 Background to Yersinia pestis Maps to Multiple Loci on Chromosome 1

PubMed Central

Tencati, Michael

2016-01-01

Yersinia pestis is a Gram-negative bacterium that is the causative agent of bubonic and pneumonic plague. It is commonly acquired by mammals such as rodents and humans via the bite of an infected flea. We previously reported that multiple substrains of the 129 mouse background are resistant to pigmentation locus-negative (pgm−) Yersinia pestis and that this phenotype maps to a 30-centimorgan (cM) region located on chromosome 1. In this study, we have further delineated this plague resistance locus to a region of less than 20 cM through the creation and phenotyping of recombinant offspring arising from novel crossovers in this region. Furthermore, our experiments have revealed that there are at least two alleles in this initial locus, both of which are required for resistance on a susceptible C57BL/6 background. These two alleles work in trans since resistance is restored in offspring possessing one allele contributed by each parent. Our studies also indicated that the Slc11a1 gene (formerly known as Nramp1) located within the chromosome1 locus is not responsible for conferring resistance to 129 mice. PMID:27481241

Comparative Omics-Driven Genome Annotation Refinement: Application across Yersiniae

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

Rutledge, Alexandra C.; Jones, Marcus B.; Chauhan, Sadhana

2012-03-27

Genome sequencing continues to be a rapidly evolving technology, yet most downstream aspects of genome annotation pipelines remain relatively stable or are even being abandoned. To date, the perceived value of manual curation for genome annotations is not offset by the real cost and time associated with the process. In order to balance the large number of sequences generated, the annotation process is now performed almost exclusively in an automated fashion for most genome sequencing projects. One possible way to reduce errors inherent to automated computational annotations is to apply data from 'omics' measurements (i.e. transcriptional and proteomic) to themore » un-annotated genome with a proteogenomic-based approach. This approach does require additional experimental and bioinformatics methods to include omics technologies; however, the approach is readily automatable and can benefit from rapid developments occurring in those research domains as well. The annotation process can be improved by experimental validation of transcription and translation and aid in the discovery of annotation errors. Here the concept of annotation refinement has been extended to include a comparative assessment of genomes across closely related species, as is becoming common in sequencing efforts. Transcriptomic and proteomic data derived from three highly similar pathogenic Yersiniae (Y. pestis CO92, Y. pestis pestoides F, and Y. pseudotuberculosis PB1/+) was used to demonstrate a comprehensive comparative omic-based annotation methodology. Peptide and oligo measurements experimentally validated the expression of nearly 40% of each strain's predicted proteome and revealed the identification of 28 novel and 68 previously incorrect protein-coding sequences (e.g., observed frameshifts, extended start sites, and translated pseudogenes) within the three current Yersinia genome annotations. Gene loss is presumed to play a major role in Y. pestis acquiring its niche as a virulent

Delineation and analysis of chromosomal regions specifying Yersinia pestis.

PubMed

Derbise, Anne; Chenal-Francisque, Viviane; Huon, Christèle; Fayolle, Corinne; Demeure, Christian E; Chane-Woon-Ming, Béatrice; Médigue, Claudine; Hinnebusch, B Joseph; Carniel, Elisabeth

2010-09-01

Yersinia pestis, the causative agent of plague, has recently diverged from the less virulent enteropathogen Yersinia pseudotuberculosis. Its emergence has been characterized by massive genetic loss and inactivation and limited gene acquisition. The acquired genes include two plasmids, a filamentous phage, and a few chromosomal loci. The aim of this study was to characterize the chromosomal regions acquired by Y. pestis. Following in silico comparative analysis and PCR screening of 98 strains of Y. pseudotuberculosis and Y. pestis, we found that eight chromosomal loci (six regions [R1pe to R6pe] and two coding sequences [CDS1pe and CDS2pe]) specified Y. pestis. Signatures of integration by site specific or homologous recombination were identified for most of them. These acquisitions and the loss of ancestral DNA sequences were concentrated in a chromosomal region opposite to the origin of replication. The specific regions were acquired very early during Y. pestis evolution and were retained during its microevolution, suggesting that they might bring some selective advantages. Only one region (R3pe), predicted to carry a lambdoid prophage, is most likely no longer functional because of mutations. With the exception of R1pe and R2pe, which have the potential to encode a restriction/modification and a sugar transport system, respectively, no functions could be predicted for the other Y. pestis-specific loci. To determine the role of the eight chromosomal loci in the physiology and pathogenicity of the plague bacillus, each of them was individually deleted from the bacterial chromosome. None of the deletants exhibited defects during growth in vitro. Using the Xenopsylla cheopis flea model, all deletants retained the capacity to produce a stable and persistent infection and to block fleas. Similarly, none of the deletants caused any acute flea toxicity. In the mouse model of infection, all deletants were fully virulent upon subcutaneous or aerosol infections. Therefore

Antibody producing capacity to the bacteriophage phi X174 in yersinia arthritis.

PubMed Central

Bucknall, R; Leirisalo-Repo, M; Laitinen, O; Jones, J V

1987-01-01

Antibody production in response to the primary immunogen bacteriophage phi X174 was investigated in 14 patients with previous yersinia arthritis (YA) and in 15 controls. HLA-B27 occurred in 10 patients with YA and in three controls. After primary and secondary immunisation the antibody responses were essentially similar both in patients with YA and controls. Consequently our results suggest that antibody response to a foreign antigen does not differ between patients with YA and a normal control population. In addition, there was no difference in peak antibody responses between individuals with HLA-B27 and those without HLA-B27. PMID:2962540

Genome-scale reconstruction of the metabolic network in Yersinia pestis CO92

NASA Astrophysics Data System (ADS)

Navid, Ali; Almaas, Eivind

2007-03-01

The gram-negative bacterium Yersinia pestis is the causative agent of bubonic plague. Using publicly available genomic, biochemical and physiological data, we have developed a constraint-based flux balance model of metabolism in the CO92 strain (biovar Orientalis) of this organism. The metabolic reactions were appropriately compartmentalized, and the model accounts for the exchange of metabolites, as well as the import of nutrients and export of waste products. We have characterized the metabolic capabilities and phenotypes of this organism, after comparing the model predictions with available experimental observations to evaluate accuracy and completeness. We have also begun preliminary studies into how cellular metabolism affects virulence.

Yersinia pestis Survival and Replication in Potential Ameba Reservoir

PubMed Central

Antolin, Michael F.; Bowen, Richard A.; Wheat, William H.; Woods, Michael; Gonzalez-Juarrero, Mercedes; Jackson, Mary

2018-01-01

Plague ecology is characterized by sporadic epizootics, then periods of dormancy. Building evidence suggests environmentally ubiquitous amebae act as feral macrophages and hosts to many intracellular pathogens. We conducted environmental genetic surveys and laboratory co-culture infection experiments to assess whether plague bacteria were resistant to digestion by 5 environmental ameba species. First, we demonstrated that Yersinia pestis is resistant or transiently resistant to various ameba species. Second, we showed that Y. pestis survives and replicates intracellularly within Dictyostelium discoideum amebae for ˃48 hours postinfection, whereas control bacteria were destroyed in <1 hour. Finally, we found that Y. pestis resides within ameba structures synonymous with those found in infected human macrophages, for which Y. pestis is a competent pathogen. Evidence supporting amebae as potential plague reservoirs stresses the importance of recognizing pathogen-harboring amebae as threats to public health, agriculture, conservation, and biodefense. PMID:29350155

Yersinia pestis Yop secretion protein F: purification, characterization, and protective efficacy against bubonic plague.

PubMed

Swietnicki, Wieslaw; Powell, Bradford S; Goodin, Jeremy

2005-07-01

Yersinia pestis is a gram-negative human pathogen that uses a type III secretion system to deliver virulence factors into human hosts. The delivery is contact-dependent and it has been proposed that polymerization of Yop secretion protein F (YscF) is used to puncture mammalian cell membranes to facilitate delivery of Yersinia outer protein effectors into host cells. To evaluate the potential immunogenicity and protective efficacy of YscF against Y. pestis, we used a purified recombinant YscF protein as a potential vaccine candidate in a mouse subcutaneous infection model. YscF was expressed and purified from Escherichia coli by immobilized metal-ion affinity chromatography and protein identity was confirmed by ion trap mass spectrometry. The recombinant protein was highly alpha-helical and formed relatively stable aggregates under physiological conditions. The properties were consistent with behavior expected for the native YscF, suggesting that the antigen was properly folded. Ten mice were inoculated subcutaneously, administered booster injections after one month, and challenged with 130 LD(50) of wild type Y. pestis CO92. Six animals in the vaccinated group but none in the control group survived the challenge. The vaccinated animals produced high levels of specific antibodies against YscF as determined by Western blot. The data were statistically significant (P = 0.053 by two-tailed Fisher's test), suggesting that the YscF protein can provide a protective immune response against lethal plague challenge during subcutaneous plague infection.

Transcriptomic and innate immune responses to Yersinia pestis in the lymph node during bubonic plague.

PubMed

Comer, Jason E; Sturdevant, Daniel E; Carmody, Aaron B; Virtaneva, Kimmo; Gardner, Donald; Long, Dan; Rosenke, Rebecca; Porcella, Stephen F; Hinnebusch, B Joseph

2010-12-01

A delayed inflammatory response is a prominent feature of infection with Yersinia pestis, the agent of bubonic and pneumonic plague. Using a rat model of bubonic plague, we examined lymph node histopathology, transcriptome, and extracellular cytokine levels to broadly characterize the kinetics and extent of the host response to Y. pestis and how it is influenced by the Yersinia virulence plasmid (pYV). Remarkably, dissemination and multiplication of wild-type Y. pestis during the bubonic stage of disease did not induce any detectable gene expression or cytokine response by host lymph node cells in the developing bubo. Only after systemic spread had led to terminal septicemic plague was a transcriptomic response detected, which included upregulation of several cytokine, chemokine, and other immune response genes. Although an initial intracellular phase of Y. pestis infection has been postulated, a Th1-type cytokine response associated with classical activation of macrophages was not observed during the bubonic stage of disease. However, elevated levels of interleukin-17 (IL-17) were present in infected lymph nodes. In the absence of pYV, sustained recruitment to the lymph node of polymorphonuclear leukocytes (PMN, or neutrophils), the major IL-17 effector cells, correlated with clearance of infection. Thus, the ability to counteract a PMN response in the lymph node appears to be a major in vivo function of the Y. pestis virulence plasmid.

Synergistic protection of mice against plague with monoclonal antibodies specific for the F1 and V antigens of Yersinia pestis.

PubMed

Hill, Jim; Copse, Catherine; Leary, Sophie; Stagg, Anthony J; Williamson, E Diane; Titball, Richard W

2003-04-01

Monoclonal antibodies specific for Yersinia pestis V antigen and F1 antigen, administered singly or in combination, protected mice in models of bubonic and pneumonic plague. Antibodies showed synergy when administered prophylactically and as a therapy 48 h postinfection. Monoclonal antibodies therefore have potential as a treatment for plague.

Identification of the interactome between fish plasma proteins and Edwardsiella tarda reveals tissue-specific strategies against bacterial infection.

PubMed

Li, Hui; Huang, Xiaoyan; Zeng, Zaohai; Peng, Xuan-Xian; Peng, Bo

2016-09-01

Elucidating the complex pathogen-host interaction is essential for a comprehensive understanding of how these remarkable agents invade their hosts and how the hosts defend against these invaders. During the infection, pathogens interact intensively with host to enable their survival, which can be revealed through their interactome. Edwardsiella tarda is a Gram-negative bacterial pathogen causing huge economic loss in aquaculture and a spectrum of intestinal and extraintestinal diseases in humans. E. tarda is an ideal model for host-pathogen investigation as it infects fish in three distinct steps: entering the host, circulating through the blood and establishing infection. We adopted a previous established proteomic approach that inactivated E. tarda cells and covalent crosslink fish plasma proteins were used to capture plasma proteins and bacterial outer membrane proteins, respectively. By the combinatorial use of proteomic and biochemical approaches, six plasma proteins and seven outer membrane proteins (OMPs) were identified. Interactions among these proteins were validated with protein-array, far-Western blotting and co-immunoprecipitation. At last, seventeen plasma protein-bacteria protein-protein interaction were confirmed to be involved in the interaction network, forming a complex interactome. Compared to our previous results, different host proteins were detected, whereas some of the bacterial proteins were similar, which indicates that hosts adopt tissue-specific strategies to cope with the same pathogen during infection. Thus, our results provide a robust demonstration of both bacterial initiators and host receptors or interacting proteins to further explore infection and anti-infective mechanisms between hosts and microbes. Copyright © 2016 Elsevier Ltd. All rights reserved.

Manipulation of host membranes by the bacterial pathogens Listeria, Francisella, Shigella and Yersinia.

PubMed

Pizarro-Cerdá, Javier; Charbit, Alain; Enninga, Jost; Lafont, Frank; Cossart, Pascale

2016-12-01

Bacterial pathogens display an impressive arsenal of molecular mechanisms that allow survival in diverse host niches. Subversion of plasma membrane and cytoskeletal functions are common themes associated to infection by both extracellular and intracellular pathogens. Moreover, intracellular pathogens modify the structure/stability of their membrane-bound compartments and escape degradation from phagocytic or autophagic pathways. Here, we review the manipulation of host membranes by Listeria monocytogenes, Francisella tularensis, Shigella flexneri and Yersinia spp. These four bacterial model pathogens exemplify generalized strategies as well as specific features observed during bacterial infection processes. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Cultural and morphological properties of the vaccine strain Yersinia pestis EV NIIEG bacteria after photodynamic inactivation

NASA Astrophysics Data System (ADS)

Ulianova, Onega V.; Lyapina, Anna M.; Khizhnyakova, Mariya A.; Laskavy, Vladislav N.; Feodorova, Valentina A.; Ulyanov, Sergey S.

2015-03-01

New method of photoinactivation of plague microbes (bacteria Yersinia pestis) has been suggested. Rate of growth of colonies of Y. pestis EV NIIEG at specific regimes of photo processing have been analyzed. Dependence of growth on exposure time and concentrations of photosensitizer (methylene blue) has been studied. Number of colony forming units of Y. pestis EV NIIEG bacteria as a function of intensity of light and concentration of methylene blue has been scrutinized.

Pyrazinamidase, CR-MOX agar, salicin fermentation-esculin hydrolysis, and D-xylose fermentation for identifying pathogenic serotypes of Yersinia enterocolitica.

PubMed Central

Farmer, J J; Carter, G P; Miller, V L; Falkow, S; Wachsmuth, I K

1992-01-01

We evaluated several simple laboratory tests that have been used to identify pathogenic serotypes of Yersinia enterocolitica or to indicate the pathogenic potential of individual strains. A total of 100 strains of Y. enterocolitica were studied, including 25 isolated during five outbreak investigations, 63 from sporadic cases, and 12 from stock cultures. The pyrazinamidase test, which does not depend on the Yersinia virulence plasmid, correctly identified 60 of 63 (95% sensitivity) strains of pathogenic serotypes and 34 of 37 (92% specificity) strains of nonpathogenic serotypes. Salicin fermentation-esculin hydrolysis (25 degrees C, 48 h) correctly identified all 63 (100% sensitivity) strains of the pathogenic serotypes and 34 of 37 (92% specificity) strains of the nonpathogenic serotypes. The results of the pyrazinamidase and salicin-esculin tests disagreed for only 7 of the 100 strains of Y. enterocolitica, and these would require additional testing. Congo red-magnesium oxalate (CR-MOX) agar determines Congo red dye uptake and calcium-dependent growth at 36 degrees C, and small red colonies are present only if the strain contains the Yersinia virulence plasmid. This test has proven to be extremely useful for freshly isolated cultures, but only 15 of 62 strains of pathogenic serotypes that had been stored for 1 to 10 years were CR-MOX positive. None of the 16 strains of Y. enterocolitica serotype O3 fermented D-xylose, so this test easily differentiated strains of this serotype, which now appears to be the most common in the United States. Although antisera that can actually be used to serotype strains of Y. enterocolitica are not readily available, the four simple tests described above can be used to screen for pathogenic serotypes. Images PMID:1400958

Structure of a complex of uridine phosphorylase from Yersinia pseudotuberculosis with the modified bacteriostatic antibacterial drug determined by X-ray crystallography and computer analysis

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

Balaev, V. V.; Lashkov, A. A., E-mail: alashkov83@gmail.com; Gabdoulkhakov, A. G.

2015-03-15

Pseudotuberculosis and bubonic plague are acute infectious diseases caused by the bacteria Yersinia pseudotuberculosis and Yersinia pestis. These diseases are treated, in particular, with trimethoprim and its modified analogues. However, uridine phosphorylases (pyrimidine nucleoside phosphorylases) that are present in bacterial cells neutralize the action of trimethoprim and its modified analogues on the cells. In order to reveal the character of the interaction of the drug with bacterial uridine phosphorylase, the atomic structure of the unligated molecule of uridine-specific pyrimidine nucleoside phosphorylase from Yersinia pseudotuberculosis (YptUPh) was determined by X-ray diffraction at 1.7 Å resolution with high reliability (R{sub work} =more » 16.2, R{sub free} = 19.4%; r.m.s.d. of bond lengths and bond angles are 0.006 Å and 1.005°, respectively; DPI = 0.107 Å). The atoms of the amino acid residues of the functionally important secondary-structure elements—the loop L9 and the helix H8—of the enzyme YptUPh were located. The three-dimensional structure of the complex of YptUPh with modified trimethoprim—referred to as 53I—was determined by the computer simulation. It was shown that 53I is a pseudosubstrate of uridine phosphorylases, and its pyrimidine-2,4-diamine group is located in the phosphate-binding site of the enzyme YptUPh.« less

Structure of a complex of uridine phosphorylase from Yersinia pseudotuberculosis with the modified bacteriostatic antibacterial drug determined by X-ray crystallography and computer analysis

NASA Astrophysics Data System (ADS)

Balaev, V. V.; Lashkov, A. A.; Gabdoulkhakov, A. G.; Seregina, T. A.; Dontsova, M. V.; Mikhailov, A. M.

2015-03-01

Pseudotuberculosis and bubonic plague are acute infectious diseases caused by the bacteria Yersinia pseudotuberculosis and Yersinia pestis. These diseases are treated, in particular, with trimethoprim and its modified analogues. However, uridine phosphorylases (pyrimidine nucleoside phosphorylases) that are present in bacterial cells neutralize the action of trimethoprim and its modified analogues on the cells. In order to reveal the character of the interaction of the drug with bacterial uridine phosphorylase, the atomic structure of the unligated molecule of uridine-specific pyrimidine nucleoside phosphorylase from Yersinia pseudotuberculosis ( YptUPh) was determined by X-ray diffraction at 1.7 Å resolution with high reliability ( R work = 16.2, R free = 19.4%; r.m.s.d. of bond lengths and bond angles are 0.006 Å and 1.005°, respectively; DPI = 0.107 Å). The atoms of the amino acid residues of the functionally important secondary-structure elements—the loop L9 and the helix H8—of the enzyme YptUPh were located. The three-dimensional structure of the complex of YptUPh with modified trimethoprim—referred to as 53I—was determined by the computer simulation. It was shown that 53I is a pseudosubstrate of uridine phosphorylases, and its pyrimidine-2,4-diamine group is located in the phosphate-binding site of the enzyme YptUPh.

Prevalence of Antibiotic-resistance Enterobacteriaceae strains Isolated from Chicken Meat at Traditional Markets in Surabaya, Indonesia

NASA Astrophysics Data System (ADS)

Yulistiani, R.; Praseptiangga, D.; Supyani; Sudibya; Raharjo, D.; Shirakawa, T.

2017-04-01

Antibiotic resistance in bacteria from the family Enterobacteriaceae is an important indicator of the emergence of resistant bacterial strains in the community. This study investigated the prevalence of antibiotic-resistant Enterobacteriaceae isolated from chicken meat sold at traditional markets in Surabaya Indonesia. In all, 203 isolates (43 Salmonella spp., 53 Escherichia coli, 16 Shigella spp., 22 Citrobacter spp., 13 Klebsiella spp, 24 Proteus spp., 15 Yersinia spp., 7 Enterobacter spp., 6 Serratia spp., 3 Edwardsiella spp. were resistant to tetracycline (69.95 %), nalidixid acid (54.19 %), sulfamethoxazole/sulfamethizole (42.36 %), chloramphenicol (12.81%), cefoxitin (6.40 %), gentamicin (5.91 %). Tetracycline was the antimicrobial that showed the highest frequency of resistance among Salmonella, E. coli, Citrobacter, Proteus and Erdwardsiella isolates, and nalidixid acid was second frequency of resistance. Overall, 124 (61.08 %) out of 203 isolates demonstrated multidrug resistance to at least two unrelated antimicrobial agents. The high rate of antimicrobial resistance in bacterial isolates from chicken meat may have major implications for human and animal health with adverse economic implications.

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.

Temperature-responsive in vitro RNA structurome of Yersinia pseudotuberculosis.

PubMed

Righetti, Francesco; Nuss, Aaron M; Twittenhoff, Christian; Beele, Sascha; Urban, Kristina; Will, Sebastian; Bernhart, Stephan H; Stadler, Peter F; Dersch, Petra; Narberhaus, Franz

2016-06-28

RNA structures are fundamentally important for RNA function. Dynamic, condition-dependent structural changes are able to modulate gene expression as shown for riboswitches and RNA thermometers. By parallel analysis of RNA structures, we mapped the RNA structurome of Yersinia pseudotuberculosis at three different temperatures. This human pathogen is exquisitely responsive to host body temperature (37 °C), which induces a major metabolic transition. Our analysis profiles the structure of more than 1,750 RNAs at 25 °C, 37 °C, and 42 °C. Average mRNAs tend to be unstructured around the ribosome binding site. We searched for 5'-UTRs that are folded at low temperature and identified novel thermoresponsive RNA structures from diverse gene categories. The regulatory potential of 16 candidates was validated. In summary, we present a dynamic bacterial RNA structurome and find that the expression of virulence-relevant functions in Y. pseudotuberculosis and reprogramming of its metabolism in response to temperature is associated with a restructuring of numerous mRNAs.

Neutrophils are important in early control of lung infection by Yersinia pestis.

PubMed

Laws, Thomas R; Davey, Martin S; Titball, Richard W; Lukaszewski, Roman

2010-04-01

In this paper we evaluate the role of neutrophils in pneumonic plague. Splenic neutrophils from naïve BALB/c mice were found to reduce numbers of culturable Yersinia pestis strain GB in suspension. A murine, BALB/c, intranasal model of pneumonic plague was used in conjunction with in vivo neutrophil ablation, using the GR-1 antibody. This treatment reduced neutrophil numbers without affecting other leukocyte numbers. Neutrophil ablated mice exhibited increased bacterial colonisation of the lung 24h post infection. Furthermore, exposure of Y. pestis to human neutrophils resulted in a 5-fold reduction in the number of viable bacterial cells, whereas, PBMCs had no effect. Crown Copyright 2010. Published by Elsevier SAS. All rights reserved.

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

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

The complete genome sequence of Yersinia pseudotuberculosis IP31758, the causative agent of Far East scarlet-like fever.

PubMed

Eppinger, Mark; Rosovitz, M J; Fricke, Wolfgang Florian; Rasko, David A; Kokorina, Galina; Fayolle, Corinne; Lindler, Luther E; Carniel, Elisabeth; Ravel, Jacques

2007-08-01

The first reported Far East scarlet-like fever (FESLF) epidemic swept the Pacific coastal region of Russia in the late 1950s. Symptoms of the severe infection included erythematous skin rash and desquamation, exanthema, hyperhemic tongue, and a toxic shock syndrome. The term FESLF was coined for the infection because it shares clinical presentations with scarlet fever caused by group A streptococci. The causative agent was later identified as Yersinia pseudotuberculosis, although the range of morbidities was vastly different from classical pseudotuberculosis symptoms. To understand the origin and emergence of the peculiar clinical features of FESLF, we have sequenced the genome of the FESLF-causing strain Y. pseudotuberculosis IP31758 and compared it with that of another Y. pseudotuberculosis strain, IP32953, which causes classical gastrointestinal symptoms. The unique gene pool of Y pseudotuberculosis IP31758 accounts for more than 260 strain-specific genes and introduces individual physiological capabilities and virulence determinants, with a significant proportion horizontally acquired that likely originated from Enterobacteriaceae and other soil-dwelling bacteria that persist in the same ecological niche. The mobile genome pool includes two novel plasmids phylogenetically unrelated to all currently reported Yersinia plasmids. An icm/dot type IVB secretion system, shared only with the intracellular persisting pathogens of the order Legionellales, was found on the larger plasmid and could contribute to scarlatinoid fever symptoms in patients due to the introduction of immunomodulatory and immunosuppressive capabilities. We determined the common and unique traits resulting from genome evolution and speciation within the genus Yersinia and drew a more accurate species border between Y. pseudotuberculosis and Y. pestis. In contrast to the lack of genetic diversity observed in the evolutionary young descending Y. pestis lineage, the population genetics of Y

Virulence markers of LCR plasmid in Indian isolates of Yersinia pestis.

PubMed

Khushiramani, Rekha; Tuteja, Urmil; Shukla, Jyoti; Panikkar, Anupama; Batra, Harsh Vardhan

2006-01-01

Presence of 10 important yop genes in Yersinia pestis isolates (18 in number) of Indian origin from 1994 plague outbreak regions of Maharashtra (6 Rattus rattus & Tetera indica rodents) and Gujarat (11 from human patients, 1 from R. rattus) and from plague endemic regions of the Deccan plateau (8 from T. indica) was located by PCR and specific enzyme immunoassay. PCRs were standardized for six effector yops (YopE, YopH, YopJ, YopM, YopO and YopT), three translocator yops (YopB, YopD and YopK) and a regulator LcrV gene. Amplification of all the 10 yop genes was observed in isolates recovered from pneumonic patients and in 5 of 7 rodents from outbreak regions. Among these, amplification of the yopD gene was absent in all eight isolates, and that of yopM in all except one (10R). One of the isolates from rodents of the Deccan plateau (24H) was consistently negative for all the yops. Cloning and expression of truncated yopM (780 bp), yopB (700 bp) and lcrV (796 bp) genes in pQE vectors with SG13009 host cells yielded recombinant proteins for generation of monoclonal antibodies for further use in enzyme immunoassay. Ten stable reactive clones for YopB, nine for YopM and six for LcrV were obtained, all of them exhibiting specific reactions only to Y. pestis. Testing of 26 Y. pestis isolates by monoclonal antibody dot-ELISA and Western blotting provided results identical to PCR, suggesting that the isolates that failed to show PCR amplification also had no expression of their respective proteins. The Y. pestis isolates of outbreak regions had their virulence factors intact in the LCR plasmid. Yersinia pestis isolates recovered from rodents of the Deccan plateau were relatively heterogeneous. It appears that a long residency of Y. pestis of nearly 100 years in the enzootic plague foci has resulted in shedding of virulence genes in the LCR plasmid region in a fairly large proportion of the organisms, possibly due to natural recombination.

Rapid biochemical screening for Salmonella, Shigella, Yersinia, and Aeromonas isolates from stool specimens.

PubMed Central

De Ryck, R; Struelens, M J; Serruys, E

1994-01-01

Four screens for the rapid (4 to 6 h) biochemical detection of pathogens from enteric isolation media are described. The Salmonella screen consisted of Kligler iron agar (KIA), motility-indole-urea-tryptophan-deamination semisolid medium (MIU-TDA), and the o-nitrophenyl-beta-D-galactopyranoside (ONPG) test; the Shigella screen consisted of KIA, MIU-TDA, the ONPG test, and the lysine decarboxylation-indole test; the Yersinia screen consisted of a rhamnose broth; the Aeromonas screen consisted of a xylose agar plate. When tested on 2,102 fresh isolates and 71 stock strains, the screens correctly detected 212 enteric pathogens (sensitivity, 100%), with a specificity of 98.1%. PMID:8077408

Negatively Charged Lipid Membranes Promote a Disorder-Order Transition in the Yersinia YscU Protein

PubMed Central

Weise, Christoph F.; Login, Frédéric H.; Ho, Oanh; Gröbner, Gerhard; Wolf-Watz, Hans; Wolf-Watz, Magnus

2014-01-01

The inner membrane of Gram-negative bacteria is negatively charged, rendering positively charged cytoplasmic proteins in close proximity likely candidates for protein-membrane interactions. YscU is a Yersinia pseudotuberculosis type III secretion system protein crucial for bacterial pathogenesis. The protein contains a highly conserved positively charged linker sequence that separates membrane-spanning and cytoplasmic (YscUC) domains. Although disordered in solution, inspection of the primary sequence of the linker reveals that positively charged residues are separated with a typical helical periodicity. Here, we demonstrate that the linker sequence of YscU undergoes a largely electrostatically driven coil-to-helix transition upon binding to negatively charged membrane interfaces. Using membrane-mimicking sodium dodecyl sulfate micelles, an NMR derived structural model reveals the induction of three helical segments in the linker. The overall linker placement in sodium dodecyl sulfate micelles was identified by NMR experiments including paramagnetic relaxation enhancements. Partitioning of individual residues agrees with their hydrophobicity and supports an interfacial positioning of the helices. Replacement of positively charged linker residues with alanine resulted in YscUC variants displaying attenuated membrane-binding affinities, suggesting that the membrane interaction depends on positive charges within the linker. In vivo experiments with bacteria expressing these YscU replacements resulted in phenotypes displaying significantly reduced effector protein secretion levels. Taken together, our data identify a previously unknown membrane-interacting surface of YscUC that, when perturbed by mutations, disrupts the function of the pathogenic machinery in Yersinia. PMID:25418176

Negatively charged lipid membranes promote a disorder-order transition in the Yersinia YscU protein.

PubMed

Weise, Christoph F; Login, Frédéric H; Ho, Oanh; Gröbner, Gerhard; Wolf-Watz, Hans; Wolf-Watz, Magnus

2014-10-21

The inner membrane of Gram-negative bacteria is negatively charged, rendering positively charged cytoplasmic proteins in close proximity likely candidates for protein-membrane interactions. YscU is a Yersinia pseudotuberculosis type III secretion system protein crucial for bacterial pathogenesis. The protein contains a highly conserved positively charged linker sequence that separates membrane-spanning and cytoplasmic (YscUC) domains. Although disordered in solution, inspection of the primary sequence of the linker reveals that positively charged residues are separated with a typical helical periodicity. Here, we demonstrate that the linker sequence of YscU undergoes a largely electrostatically driven coil-to-helix transition upon binding to negatively charged membrane interfaces. Using membrane-mimicking sodium dodecyl sulfate micelles, an NMR derived structural model reveals the induction of three helical segments in the linker. The overall linker placement in sodium dodecyl sulfate micelles was identified by NMR experiments including paramagnetic relaxation enhancements. Partitioning of individual residues agrees with their hydrophobicity and supports an interfacial positioning of the helices. Replacement of positively charged linker residues with alanine resulted in YscUC variants displaying attenuated membrane-binding affinities, suggesting that the membrane interaction depends on positive charges within the linker. In vivo experiments with bacteria expressing these YscU replacements resulted in phenotypes displaying significantly reduced effector protein secretion levels. Taken together, our data identify a previously unknown membrane-interacting surface of YscUC that, when perturbed by mutations, disrupts the function of the pathogenic machinery in Yersinia.

The Yersinia Virulence Factor YopM Hijacks Host Kinases to Inhibit Type III Effector-Triggered Activation of the Pyrin Inflammasome.

PubMed

Chung, Lawton K; Park, Yong Hwan; Zheng, Yueting; Brodsky, Igor E; Hearing, Patrick; Kastner, Daniel L; Chae, Jae Jin; Bliska, James B

2016-09-14

Pathogenic Yersinia, including Y. pestis, the agent of plague in humans, and Y. pseudotuberculosis, the related enteric pathogen, deliver virulence effectors into host cells via a prototypical type III secretion system to promote pathogenesis. These effectors, termed Yersinia outer proteins (Yops), modulate multiple host signaling responses. Studies in Y. pestis and Y. pseudotuberculosis have shown that YopM suppresses infection-induced inflammasome activation; however, the underlying molecular mechanism is largely unknown. Here we show that YopM specifically restricts the pyrin inflammasome, which is triggered by the RhoA-inactivating enzymatic activities of YopE and YopT, in Y. pseudotuberculosis-infected macrophages. The attenuation of a yopM mutant is fully reversed in pyrin knockout mice, demonstrating that YopM inhibits pyrin to promote virulence. Mechanistically, YopM recruits and activates the host kinases PRK1 and PRK2 to negatively regulate pyrin by phosphorylation. These results show how a virulence factor can hijack host kinases to inhibit effector-triggered pyrin inflammasome activation. Copyright © 2016 Elsevier Inc. All rights reserved.

Duration of plague (Yersinia pestis) outbreaks in black-tailed prairie dog (Cynomys ludovicianus) colonies of northern Colorado.

PubMed

St Romain, Krista; Tripp, Daniel W; Salkeld, Daniel J; Antolin, Michael F

2013-09-01

Plague, caused by the bacterium Yersinia pestis, triggers die-offs in colonies of black-tailed prairie dogs (Cynomys ludovicianus), but the time-frame of plague activity is not well understood. We document plague activity in fleas from prairie dogs and their burrows on three prairie dog colonies that suffered die-offs. We demonstrate that Y. pestis transmission occurs over periods from several months to over a year in prairie dog populations before observed die-offs.

Edwardsiella ictaluri Encodes an Acid-Activated Urease That Is Required for Intracellular Replication in Channel Catfish (Ictalurus punctatus) Macrophages▿

PubMed Central

Booth, Natha J.; Beekman, Judith B.; Thune, Ronald L.

2009-01-01

Genomic analysis indicated that Edwardsiella ictaluri encodes a putative urease pathogenicity island containing the products of nine open reading frames, including urea and ammonium transporters. In vitro studies with wild-type E. ictaluri and a ureG::kan urease mutant strain indicated that E. ictaluri is significantly tolerant of acid conditions (pH 3.0) but that urease activity is not required for acid tolerance. Growth studies demonstrated that E. ictaluri is unable to grow at pH 5 in the absence of urea but is able to elevate the environmental pH from pH 5 to pH 7 and grow when exogenous urea is available. Substantial production of ammonia was observed for wild-type E. ictaluri in vitro in the presence of urea at low pH, and optimal activity occurred at pH 2 to 3. No ammonia production was detected for the urease mutant. Proteomic analysis with two-dimensional gel electrophoresis indicated that urease proteins are expressed at both pH 5 and pH 7, although urease activity is detectable only at pH 5. Urease was not required for initial invasion of catfish but was required for subsequent proliferation and virulence. Urease was not required for initial uptake or survival in head kidney-derived macrophages but was required for intracellular replication. Intracellular replication of wild-type E. ictaluri was significantly enhanced when urea was present, indicating that urease plays an important role in intracellular survival and replication, possibly through neutralization of the acidic environment of the phagosome. PMID:19749068

Further development of raccoon poxvirus-vectored vaccines against plague (Yersinia pestis)

USGS Publications Warehouse

Rocke, Tonie E.; Iams, Keith P.; Dawe, S.; Smith, Susan; Williamson, Judy L.; Heisey, Dennis M.; Osorio, Jorge E.

2009-01-01

In previous studies, we demonstrated protection against plague in mice and prairie dogs using a raccoon pox (RCN) virus-vectored vaccine that expressed the F1 capsular antigen of Yersinia pestis. In order to improve vaccine efficacy, we have now constructed additional RCN-plague vaccines containing two different forms of the lcrV (V) gene, including full-length (Vfull) and a truncated form (V307). Mouse challenge studies with Y. pestis strain CO92 showed that vaccination with a combination of RCN-F1 and the truncated V construct (RCN-V307) provided the greatest improvement (P = 0.01) in protection against plague over vaccination with RCN-F1 alone. This effect was mediated primarily by anti-F1 and anti-V antibodies and both contributed independently to increased survival of vaccinated mice.

Further development of raccoon poxvirus-vectored vaccines against plague (Yersinia pestis).

PubMed

Rocke, Tonie E; Iams, Keith P; Dawe, Sandra; Smith, Susan R; Williamson, Judy L; Heisey, Dennis M; Osorio, Jorge E

2009-12-11

In previous studies, we demonstrated protection against plague in mice and prairie dogs using a raccoon pox (RCN) virus-vectored vaccine that expressed the F1 capsular antigen of Yersinia pestis. In order to improve vaccine efficacy, we have now constructed additional RCN-plague vaccines containing two different forms of the lcrV (V) gene, including full-length (Vfull) and a truncated form (V307). Mouse challenge studies with Y. pestis strain CO92 showed that vaccination with a combination of RCN-F1 and the truncated V construct (RCN-V307) provided the greatest improvement (P=0.01) in protection against plague over vaccination with RCN-F1 alone. This effect was mediated primarily by anti-F1 and anti-V antibodies and both contributed independently to increased survival of vaccinated mice.

Short-term starvation and realimentation helps stave off Edwardsiella tarda infection in red sea bream (Pagrus major).

PubMed

Mohapatra, Sipra; Chakraborty, Tapas; Reza, Mohammad Ali Noman; Shimizu, Sonoko; Matsubara, Takahiro; Ohta, Kohei

2017-04-01

Dietary regime modifications have been an integral part of health and healing practices throughout the animal kingdom. Thus, to assess the effects of periodic starvation and refeeding schedule on the physiological and immunological perturbations in Edwardsiella tarda infected red sea bream, we conducted a 20day experiment using 4 treatment groups, namely, pre-fed placebo (PFP); pre-starved placebo (PSP); pre-fed infected (PFI); and pre-starved infected (PSI), wherein a 5h E. tarda infection was done on the 11th day. In the present investigation, the pre-starved groups showed significant (P<0.05) alterations in the liver Hexokinase and Glucose-6-phosphatase activity. The pre-starved fish also exhibited significant (P<0.05) increment in the hepatosomatic index, along with increased hepatic glycogen content, in a time dependent fashion. The PPAR (peroxisome proliferator activated receptors)α transcription in the pre-starved group decreased significantly (P<0.05) by 10dai, while the PPARγ showcased a reverse pattern. The transcription of Hepcidin1 and Transferrin (iron homeostasis related genes), and Cathepsin D and Ubiquitin (programmed cell death related genes) portrayed a time responsive decrease and increase in PSI and PFI groups, respectively. Additionally, in comparison to the PFI group, the PSI fish demonstrated substantially reduced oxidative stress level. Fluorescent Immunohistochemistry showed significant (P<0.05) increase in p63 positive cells in the 10dai PFI fish in relation to the PSI group. Therefore, these findings provide new insight into the beneficial role of alternating starvation and refeeding schedule, preferably short-term starvation prior to an infection, in order to obtain better capability to battle against E. tarda infection in red sea bream. Copyright © 2017 Elsevier Inc. All rights reserved.

Effects of ammonia stress, dietary linseed oil and Edwardsiella ictaluri challenge on juvenile darkbarbel catfish Pelteobagrus vachelli.

PubMed

Li, Ming; Yu, Na; Qin, Jian G; Li, Erchao; Du, Zhenyu; Chen, Liqiao

2014-05-01

A two-stage study was carried out to test the response of juvenile darkbarbel catfish Pelteobagrus vachelli to ammonia stress, dietary lipid and bacterial challenge. At stage 1, the catfish (0.99 ± 0.01 g) fed a commercial diet were exposed to 0.01 and 5.70 mg L(-1) total ammonia nitrogen in nine replicates for 14 days. At stage 2, all fish previously exposed to either low or high ammonia were separately transferred into low ammonia (<0.01 mg L(-1)), and divided into three feeding groups. Fish were then fed three levels of linseed oil (0, 2 and 4%) in triplicate for 46 days. Fish growth performance and immune response were low in high ammonia at stage 1. At stage 2, fish growth and immune response were not significantly different between fish previously exposed to low and high ammonia in all diets. Fish fed 4% linseed oil showed the greatest weight gain, feed efficiency ratio, red blood cells, hemoglobin and hematocrit, and achieved higher lysozyme activity, phagocytic index, respiratory burst and total immunoglobulin than fish fed 0% linseed oil, but did not differ from fish fed 2% linseed oil regardless of previous ammonia exposure. After 14-day infection of Edwardsiella ictaluri, cumulative mortality of fish previously exposed to low ammonia was lower than that of fish exposed to high ammonia in all diets. Cumulative mortality of fish fed 0% linseed oil was highest, but the antibody titer of fish fed 4% linseed oil was highest regardless of previous ammonia treatments. This study indicates that ammonia stress has a lasting effect even after ammonia is lowed, but the adverse effect on fish can be mitigated through manipulation of dietary oil inclusion, especially under the challenge of pathogenic bacteria. Copyright © 2014 Elsevier Ltd. All rights reserved.

Quantitative trait loci detection of Edwardsiella tarda resistance in Japanese flounder Paralichthys olivaceus using bulked segregant analysis

NASA Astrophysics Data System (ADS)

Wang, Xiaoxia; Xu, Wenteng; Liu, Yang; Wang, Lei; Sun, Hejun; Wang, Lei; Chen, Songlin

2016-11-01

In recent years, Edwardsiella tarda has become one of the most deadly pathogens of Japanese flounder ( Paralichthys olivaceus), causing serious annual losses in commercial production. In contrast to the rapid advances in the aquaculture of P. olivaceus, the study of E. tarda resistance-related markers has lagged behind, hindering the development of a disease-resistant strain. Thus, a marker-trait association analysis was initiated, combining bulked segregant analysis (BSA) and quantitative trait loci (QTL) mapping. Based on 180 microsatellite loci across all chromosomes, 106 individuals from the F1333 (♀: F0768 ×♂: F0915) (Nomenclature rule: F+year+family number) were used to detect simple sequence repeats (SSRs) and QTLs associated with E. tarda resistance. After a genomic scan, three markers (Scaffold 404-21589, Scaffold 404-21594 and Scaffold 270-13812) from the same linkage group (LG)-1 exhibited a significant difference between DNA, pooled/bulked from the resistant and susceptible groups (P <0.001). Therefore, 106 individuals were genotyped using all the SSR markers in LG1 by single marker analysis. Two different analytical models were then employed to detect SSR markers with different levels of significance in LG1, where 17 and 18 SSR markers were identified, respectively. Each model found three resistance-related QTLs by composite interval mapping (CIM). These six QTLs, designated qE1-6, explained 16.0%-89.5% of the phenotypic variance. Two of the QTLs, qE-2 and qE-4, were located at the 66.7 cM region, which was considered a major candidate region for E. tarda resistance. This study will provide valuable data for further investigations of E. tarda resistance genes and facilitate the selective breeding of disease-resistant Japanese flounder in the future.

The Aspartate-Semialdehyde Dehydrogenase of Edwardsiella ictaluri and Its Use as Balanced-Lethal System in Fish Vaccinology

PubMed Central

Santander, Javier; Xin, Wei; Yang, Zhao; Curtiss, Roy

2010-01-01

asdA mutants of Gram-negative bacteria have an obligate requirement for diaminopimelic acid (DAP), which is an essential constituent of the peptidoglycan layer of the cell wall of these organisms. In environments deprived of DAP, i.e., animal tissues, they will undergo lysis. Deletion of the asdA gene has previously been exploited to develop antibiotic-sensitive strains of live attenuated recombinant bacterial vaccines. Introduction of an Asd+ plasmid into a ΔasdA mutant makes the bacterial strain plasmid-dependent. This dependence on the Asd+ plasmid vector creates a balanced-lethal complementation between the bacterial strain and the recombinant plasmid. E. ictaluri is an enteric Gram-negative fish pathogen that causes enteric septicemia in catfish. Because E. ictaluri is a nasal/oral invasive intracellular pathogen, this bacterium is a candidate to develop a bath/oral live recombinant attenuated Edwardsiella vaccine (RAEV) for the catfish aquaculture industry. As a first step to develop an antibiotic-sensitive RAEV strain, we characterized and deleted the E. ictaluri asdA gene. E. ictaluri ΔasdA01 mutants exhibit an absolute requirement for DAP to grow. The asdA gene of E. ictaluri was complemented by the asdA gene from Salmonella. Several Asd+ expression vectors with different origins of replication were transformed into E. ictaluri ΔasdA01. Asd+ vectors were compatible with the pEI1 and pEI2 E. ictaluri native plasmids. The balanced-lethal system was satisfactorily evaluated in vivo. Recombinant GFP, PspA, and LcrV proteins were synthesized by E. ictaluri ΔasdA01 harboring Asd+ plasmids. Here we constructed a balanced-lethal system, which is the first step to develop an antibiotic-sensitive RAEV for the aquaculture industry. PMID:21209920

The aspartate-semialdehyde dehydrogenase of Edwardsiella ictaluri and its use as balanced-lethal system in fish vaccinology.

PubMed

Santander, Javier; Xin, Wei; Yang, Zhao; Curtiss, Roy

2010-12-29

asdA mutants of gram-negative bacteria have an obligate requirement for diaminopimelic acid (DAP), which is an essential constituent of the peptidoglycan layer of the cell wall of these organisms. In environments deprived of DAP, i.e., animal tissues, they will undergo lysis. Deletion of the asdA gene has previously been exploited to develop antibiotic-sensitive strains of live attenuated recombinant bacterial vaccines. Introduction of an Asd(+) plasmid into a ΔasdA mutant makes the bacterial strain plasmid-dependent. This dependence on the Asd(+) plasmid vector creates a balanced-lethal complementation between the bacterial strain and the recombinant plasmid. E. ictaluri is an enteric gram-negative fish pathogen that causes enteric septicemia in catfish. Because E. ictaluri is a nasal/oral invasive intracellular pathogen, this bacterium is a candidate to develop a bath/oral live recombinant attenuated Edwardsiella vaccine (RAEV) for the catfish aquaculture industry. As a first step to develop an antibiotic-sensitive RAEV strain, we characterized and deleted the E. ictaluri asdA gene. E. ictaluri ΔasdA01 mutants exhibit an absolute requirement for DAP to grow. The asdA gene of E. ictaluri was complemented by the asdA gene from Salmonella. Several Asd(+) expression vectors with different origins of replication were transformed into E. ictaluri ΔasdA01. Asd(+) vectors were compatible with the pEI1 and pEI2 E. ictaluri native plasmids. The balanced-lethal system was satisfactorily evaluated in vivo. Recombinant GFP, PspA, and LcrV proteins were synthesized by E. ictaluri ΔasdA01 harboring Asd(+) plasmids. Here we constructed a balanced-lethal system, which is the first step to develop an antibiotic-sensitive RAEV for the aquaculture industry.

Proteolytic processing of the Yersinia pestis YapG autotransporter by the omptin protease Pla and the contribution of YapG to murine plague pathogenesis

PubMed Central

Lane, M. Chelsea; Lenz, Jonathan D.

2013-01-01

Autotransporter protein secretion represents one of the simplest forms of secretion across Gram-negative bacterial membranes. Once secreted, autotransporter proteins either remain tethered to the bacterial surface or are released following proteolytic cleavage. Autotransporters possess a diverse array of virulence-associated functions such as motility, cytotoxicity, adherence and autoaggregation. To better understand the role of autotransporters in disease, our research focused on the autotransporters of Yersinia pestis, the aetiological agent of plague. Y. pestis strain CO92 has nine functional conventional autotransporters, referred to as Yaps for Yersinia autotransporter proteins. Three Yaps have been directly implicated in virulence using established mouse models of plague infection (YapE, YapJ and YapK). Whilst previous studies from our laboratory have shown that most of the CO92 Yaps are cell associated, YapE and YapG are processed and released by the omptin protease Pla. In this study, we identified the Pla cleavage sites in YapG that result in many released forms of YapG in Y. pestis, but not in the evolutionarily related gastrointestinal pathogen, Yersinia pseudotuberculosis, which lacks Pla. Furthermore, we showed that YapG does not contribute to Y. pestis virulence in established mouse models of bubonic and pneumonic infection. As Y. pestis has a complex life cycle involving a wide range of mammalian hosts and a flea vector for transmission, it remains to be elucidated whether YapG has a measurable role in any other stage of plague disease. PMID:23657527

Starvation beneficially influences the liver physiology and nutrient metabolism in Edwardsiella tarda infected red sea bream (Pagrus major).

PubMed

Mohapatra, Sipra; Chakraborty, Tapas; Shimizu, Sonoko; Urasaki, Shintaro; Matsubara, Takahiro; Nagahama, Yoshitaka; Ohta, Kohei

2015-11-01

Dietary compromises, especially food restrictions, possess species-specific effects on the health status and infection control in several organisms, including fish. To understand the starvation-mediated physiological responses in Edwardsiella tarda infected red sea bream, especially in the liver, we performed a 20-day starvation experiment using 4 treatment (2 fed and 2 starved) groups, namely, fed-placebo, starved-placebo, fed-infected, and starved-infected, wherein bacterial exposure was done on the 11th day. In the present study, the starved groups showed reduced hepatosomatic index and drastic depletion in glycogen storage and vacuole formation. The fed-infected fish showed significant (P<0.05) increase in catalase and superoxide dismutase activity in relation to its starved equivalent. Significant (P<0.05) alteration in glucose and energy metabolism, as evident from hexokinase and glucose-6-phosphate dehydrogenase activity, was recorded in the starved groups. Interestingly, coinciding with the liver histology, PPAR (peroxisome proliferator activated receptors) α transcription followed a time-dependent activation in starved groups while PPARγ exhibited an opposite pattern. The transcription of hepcidin 1 and transferrin, initially increased in 0dai (days after infection) starved fish but reduced significantly (P<0.05) at later stages. Two-color immunohistochemistry and subsequent cell counting showed significant increase in P63-positive cells at 0dai and 5dai but later reduced slightly at 10dai. Similar results were also obtained in the lysosomal (cathepsin D) and non-lysosomal (ubiquitin) gene transcription level. All together, our data suggest that starvation exerts multidirectional responses, which allows for better physiological adaptations during any infectious period, in red sea bream. Copyright © 2015 Elsevier Inc. All rights reserved.

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 pestis: still a plague in the 21st century.

PubMed

Josko, Deborah

2004-01-01

Yersinia pestis, the causative agent of plague, is an aerobic, non-motile, gram-negative bacillus belonging to the family Enterobacteriacea. It is a zoonotic infection transmitted to humans via the bite of a flea. Three clinical forms of human plague exist: bubonic, pneumonic, and septicemic. Many important virulence factors associated with this organism are responsible for its extreme pathogenicity and high mortality rates. The bubonic form of plague is usually not transmitted human to human but the pneumonic form is--through inhalation of contaminated aerosol droplets. The pneumonic plague would be the form most likely implicated in the event of an intentional attack. Inhalation of aerosols can cause devastating consequences resulting in many casualties. Unless antibiotics are administered within 24 hours of the initial symptoms, death is inevitable. Its potential for use as a biological weapon is of major concern to public health officials.

Early emergence of Yersinia pestis as a severe respiratory pathogen.

PubMed

Zimbler, Daniel L; Schroeder, Jay A; Eddy, Justin L; Lathem, Wyndham W

2015-06-30

Yersinia pestis causes the fatal respiratory disease pneumonic plague. Y. pestis recently evolved from the gastrointestinal pathogen Y. pseudotuberculosis; however, it is not known at what point Y. pestis gained the ability to induce a fulminant pneumonia. Here we show that the acquisition of a single gene encoding the protease Pla was sufficient for the most ancestral, deeply rooted strains of Y. pestis to cause pneumonic plague, indicating that Y. pestis was primed to infect the lungs at a very early stage in its evolution. As Y. pestis further evolved, modern strains acquired a single amino-acid modification within Pla that optimizes protease activity. While this modification is unnecessary to cause pneumonic plague, the substitution is instead needed to efficiently induce the invasive infection associated with bubonic plague. These findings indicate that Y. pestis was capable of causing pneumonic plague before it evolved to optimally cause invasive infections in mammals.

The Yersinia pestis Rcs phosphorelay inhibits biofilm formation by repressing transcription of the diguanylate cyclase gene hmsT.

PubMed

Sun, Yi-Cheng; Guo, Xiao-Peng; Hinnebusch, B Joseph; Darby, Creg

2012-04-01

Yersinia pestis, which causes bubonic plague, forms biofilms in fleas, its insect vectors, as a means to enhance transmission. Biofilm development is positively regulated by hmsT, encoding a diguanylate cyclase that synthesizes the bacterial second messenger cyclic-di-GMP. Biofilm development is negatively regulated by the Rcs phosphorelay signal transduction system. In this study, we show that Rcs-negative regulation is accomplished by repressing transcription of hmsT.

Biologically active ligands for yersinia outer protein H (YopH): feature based pharmacophore screening, docking and molecular dynamics studies.

PubMed

Tamilvanan, Thangaraju; Hopper, Waheeta

2014-01-01

Yersinia pestis, a Gram negative bacillus, spreads via lymphatic to lymph nodes and to all organs through the bloodstream, causing plague. Yersinia outer protein H (YopH) is one of the important effector proteins, which paralyzes lymphocytes and macrophages by dephosphorylating critical tyrosine kinases and signal transduction molecules. The purpose of the study is to generate a three-dimensional (3D) pharmacophore model by using diverse sets of YopH inhibitors, which would be useful for designing of potential antitoxin. In this study, we have selected 60 biologically active inhibitors of YopH to perform Ligand based pharmacophore study to elucidate the important structural features responsible for biological activity. Pharmacophore model demonstrated the importance of two acceptors, one hydrophobic and two aromatic features toward the biological activity. Based on these features, different databases were screened to identify novel compounds and these ligands were subjected for docking, ADME properties and Binding energy prediction. Post docking validation was performed using molecular dynamics simulation for selected ligands to calculate the Root Mean Square Deviation (RMSD) and Root Mean Square Fluctuation (RMSF). The ligands, ASN03270114, Mol_252138, Mol_31073 and ZINC04237078 may act as inhibitors against YopH of Y. pestis.

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.

Galectin-1-Driven Tolerogenic Programs Aggravate Yersinia enterocolitica Infection by Repressing Antibacterial Immunity.

PubMed

Davicino, Roberto C; Méndez-Huergo, Santiago P; Eliçabe, Ricardo J; Stupirski, Juan C; Autenrieth, Ingo; Di Genaro, María S; Rabinovich, Gabriel A

2017-08-15

Yersinia enterocolitica is an enteropathogenic bacterium that causes gastrointestinal disorders, as well as extraintestinal manifestations. To subvert the host's immune response, Y. enterocolitica uses a type III secretion system consisting of an injectisome and effector proteins, called Yersinia outer proteins (Yops), that modulate activation, signaling, and survival of immune cells. In this article, we show that galectin-1 (Gal-1), an immunoregulatory lectin widely expressed in mucosal tissues, contributes to Y. enterocolitica pathogenicity by undermining protective antibacterial responses. We found higher expression of Gal-1 in the spleen and Peyer's patches of mice infected orogastrically with Y. enterocolitica serotype O:8 compared with noninfected hosts. This effect was prevented when mice were infected with Y. enterocolitica lacking YopP or YopH, two critical effectors involved in bacterial immune evasion. Consistent with a regulatory role for this lectin during Y. enterocolitica pathogenesis, mice lacking Gal-1 showed increased weight and survival, lower bacterial load, and attenuated intestinal pathology compared with wild-type mice. These protective effects involved modulation of NF-κB activation, TNF production, and NO synthesis in mucosal tissue and macrophages, as well as systemic dysregulation of IL-17 and IFN-γ responses. In vivo neutralization of these proinflammatory cytokines impaired bacterial clearance and eliminated host protection conferred by Gal-1 deficiency. Finally, supplementation of recombinant Gal-1 in mice lacking Gal-1 or treatment of wild-type mice with a neutralizing anti-Gal-1 mAb confirmed the immune inhibitory role of this endogenous lectin during Y. enterocolitica infection. Thus, targeting Gal-1-glycan interactions may contribute to reinforce antibacterial responses by reprogramming innate and adaptive immune mechanisms. Copyright © 2017 by The American Association of Immunologists, Inc.

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

An additional step in the transmission of Yersinia pestis?

PubMed Central

Easterday, W Ryan; Kausrud, Kyrre L; Star, Bastiaan; Heier, Lise; Haley, Bradd J; Ageyev, Vladimir; Colwell, Rita R; Stenseth, Nils Chr

2012-01-01

Plague, caused by the bacterium Yersinia pestis, is a mammalian vector-borne disease, transmitted by fleas that serve as the vector between rodent hosts. For many pathogens, including Y. pestis, there are strong evolutionary pressures that lead to a reduction in ‘useless genes', with only those retained that reflect function in the specific environment inhabited by the pathogen. Genetic traits critical for survival and transmission between two environments, the rodent and the flea, are conserved in epizootic/epidemic plague strains. However, there are genes that remain conserved for which no function in the flea–rodent cycle has yet been observed, indicating an additional environment may exist in the transmission cycle of plague. Here, we present evidence for highly conserved genes that suggests a role in the persistence of Y. pestis after death of its host. Furthermore, maintenance of these genes points to Y. pestis traversing a post-mortem path between, and possibly within, epizootic periods and offering insight into mechanisms that may allow Y. pestis an alternative route of transmission in the natural environment. PMID:21833036

Fibrinolytic and procoagulant activities of Yersinia pestis and Salmonella enterica.

PubMed

Korhonen, T K

2015-06-01

Pla of the plague bacterium Yersinia pestis and PgtE of the enteropathogen Salmonella enterica are surface-exposed, transmembrane β-barrel proteases of the omptin family that exhibit a complex array of interactions with the hemostatic systems in vitro, and both proteases are established virulence factors. Pla favors fibrinolysis by direct activation of plasminogen, inactivation of the serpins plasminogen activator inhibitor-1 and α2-antiplasmin, inactivation of the thrombin-activable fibrinolysis inhibitor, and activation of single-chain urokinase. PgtE is structurally very similar but exhibits partially different functions and differ in expression control. PgtE proteolysis targets control aspects of fibrinolysis, and mimicry of matrix metalloproteinases enhances cell migration that should favor the intracellular spread of the bacterium. Enzymatic activity of both proteases is strongly influenced by the environment-induced variations in lipopolysaccharide that binds to the β-barrel. Both proteases cleave the tissue factor pathway inhibitor and thus also express procoagulant activity. © 2015 International Society on Thrombosis and Haemostasis.

Early emergence of Yersinia pestis as a severe respiratory pathogen

PubMed Central

Zimbler, Daniel L.; Schroeder, Jay A.; Eddy, Justin L.; Lathem, Wyndham W.

2015-01-01

Yersinia pestis causes the fatal respiratory disease pneumonic plague. Y. pestis recently evolved from the gastrointestinal pathogen Y. pseudotuberculosis; however, it is not known at what point Y. pestis gained the ability to induce a fulminant pneumonia. Here we show that the acquisition of a single gene encoding the protease Pla was sufficient for the most ancestral, deeply rooted strains of Y. pestis to cause pneumonic plague, indicating that Y. pestis was primed to infect the lungs at a very early stage in its evolution. As Y. pestis further evolved, modern strains acquired a single amino-acid modification within Pla that optimizes protease activity. While this modification is unnecessary to cause pneumonic plague, the substitution is instead needed to efficiently induce the invasive infection associated with bubonic plague. These findings indicate that Y. pestis was capable of causing pneumonic plague before it evolved to optimally cause invasive infections in mammals. PMID:26123398

Effect of Ichthyophthirius multifiliis parasitism on the survival, hematology and bacterial load in channel catfish previously exposed to Edwardsiella ictaluri.

PubMed

Shoemaker, Craig A; Martins, Maurício L; Xu, De-Hai; Klesius, Phillip H

2012-11-01

The effect of Ichthyophthirius multifiliis (Ich) parasitism on survival, hematology and bacterial load in channel catfish, Ictalurus punctatus, previously exposed to Edwardsiella ictaluri was studied. Fish were exposed to E. ictaluri 1 day prior to Ich in the following treatments: (1) infected by E. ictaluri and Ich at 2,500 theronts/fish; (2) infected by E. ictaluri only; (3) infected by Ich at 2,500 theronts/fish only; and (4) non infected control. Mortality was significantly higher in fish previously exposed to E. ictaluri and then infected by Ich (71.1 %). Mortalities were 26.7 %, 28.9 % and 0 % for fish infected by E. ictaluri only, by Ich only and non-infected control, respectively. Quantitative polymerase chain reaction demonstrated the presence of E. ictaluri in the brain, gill, kidney and liver of fish infected with E. ictaluri regardless of Ich parasitism. At day 8, E. ictaluri parasitized fish had significantly more bacteria present in the brain, gill and liver, with no bacteria detected in these organs in the E. ictaluri-only treatment, suggesting that the bacteria persisted longer in parasitized fish. Decreased red blood cells count and hematocrit in fish at days 8 and 19 after co-infection suggests chronic anemia. Lymphocyte numbers significantly decreased in all infected treatments versus the non-infected controls at days 2, 8 and 19. Lymphopenia suggests that lymphocytes were actively involved in the immune response. Bacterial clearance was probably influenced by the stress of parasitism and/or the mucosal response induced by ectoparasitic Ich that resulted in the higher mortality seen in the co-infected treatment.

Glutathionylation of Yersinia pestis LcrV and Its Effects on Plague Pathogenesis.

PubMed

Mitchell, Anthony; Tam, Christina; Elli, Derek; Charlton, Thomas; Osei-Owusu, Patrick; Fazlollahi, Farbod; Faull, Kym F; Schneewind, Olaf

2017-05-16

Glutathionylation, the formation of reversible mixed disulfides between glutathione and protein cysteine residues, is a posttranslational modification previously observed for intracellular proteins of bacteria. Here we show that Yersinia pestis LcrV, a secreted protein capping the type III secretion machine, is glutathionylated at Cys 273 and that this modification promotes association with host ribosomal protein S3 (RPS3), moderates Y. pestis type III effector transport and killing of macrophages, and enhances bubonic plague pathogenesis in mice and rats. Secreted LcrV was purified and analyzed by mass spectrometry to reveal glutathionylation, a modification that is abolished by the codon substitution Cys 273 Ala in lcrV Moreover, the lcrV C273A mutation enhanced the survival of animals in models of bubonic plague. Investigating the molecular mechanism responsible for these virulence attributes, we identified macrophage RPS3 as a ligand of LcrV, an association that is perturbed by the Cys 273 Ala substitution. Furthermore, macrophages infected by the lcrV C273A variant displayed accelerated apoptotic death and diminished proinflammatory cytokine release. Deletion of gshB , which encodes glutathione synthetase of Y. pestis , resulted in undetectable levels of intracellular glutathione, and we used a Y. pestis Δ gshB mutant to characterize the biochemical pathway of LcrV glutathionylation, establishing that LcrV is modified after its transport to the type III needle via disulfide bond formation with extracellular oxidized glutathione. IMPORTANCE Yersinia pestis , the causative agent of plague, has killed large segments of the human population; however, the molecular bases for the extraordinary virulence attributes of this pathogen are not well understood. We show here that LcrV, the cap protein of bacterial type III secretion needles, is modified by host glutathione and that this modification contributes to the high virulence of Y. pestis in mouse and rat

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.

The Complete Genome Sequence of Yersinia pseudotuberculosis IP31758, the Causative Agent of Far East Scarlet-Like Fever

PubMed Central

Eppinger, Mark; Rosovitz, M. J; Fricke, Wolfgang Florian; Rasko, David A; Kokorina, Galina; Fayolle, Corinne; Lindler, Luther E; Carniel, Elisabeth; Ravel, Jacques

2007-01-01

The first reported Far East scarlet-like fever (FESLF) epidemic swept the Pacific coastal region of Russia in the late 1950s. Symptoms of the severe infection included erythematous skin rash and desquamation, exanthema, hyperhemic tongue, and a toxic shock syndrome. The term FESLF was coined for the infection because it shares clinical presentations with scarlet fever caused by group A streptococci. The causative agent was later identified as Yersinia pseudotuberculosis, although the range of morbidities was vastly different from classical pseudotuberculosis symptoms. To understand the origin and emergence of the peculiar clinical features of FESLF, we have sequenced the genome of the FESLF-causing strain Y. pseudotuberculosis IP31758 and compared it with that of another Y. pseudotuberculosis strain, IP32953, which causes classical gastrointestinal symptoms. The unique gene pool of Y pseudotuberculosis IP31758 accounts for more than 260 strain-specific genes and introduces individual physiological capabilities and virulence determinants, with a significant proportion horizontally acquired that likely originated from Enterobacteriaceae and other soil-dwelling bacteria that persist in the same ecological niche. The mobile genome pool includes two novel plasmids phylogenetically unrelated to all currently reported Yersinia plasmids. An icm/dot type IVB secretion system, shared only with the intracellular persisting pathogens of the order Legionellales, was found on the larger plasmid and could contribute to scarlatinoid fever symptoms in patients due to the introduction of immunomodulatory and immunosuppressive capabilities. We determined the common and unique traits resulting from genome evolution and speciation within the genus Yersinia and drew a more accurate species border between Y. pseudotuberculosis and Y. pestis. In contrast to the lack of genetic diversity observed in the evolutionary young descending Y. pestis lineage, the population genetics of Y

Proteomic Characterization of Yersinia pestis Virulence

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

Chromy, B; Murphy, G; Gonzales, A

2005-01-05

Yersinia pestis, the etiological agent of plague, functions via the Type III secretion mechanism whereby virulence factors are induced upon interactions with a mammalian host. Here, the Y. pestis proteome was studied by two-dimensional differential gel electrophoresis (2-D DIGE) under physiologically relevant growth conditions mimicking the calcium concentrations and temperatures that the pathogen would encounter in the flea vector and upon interaction with the mammalian host. Over 4100 individual protein spots were detected of which hundreds were differentially expressed in the entire comparative experiment. A total of 43 proteins that were differentially expressed between the vector and host growth conditionsmore » were identified by mass spectrometry. Expected differences in expression were observed for several known virulence factors including catalase-peroxidase (KatY), murine toxin (Ymt), plasminogen activator (Pla), and F1 capsule antigen (Caf1), as well as putative virulence factors. Chaperone proteins and signaling molecules hypothesized to be involved in virulence due to their role in Type III secretion were also identified. Other differentially expressed proteins not previously reported to contribute to virulence are candidates for more detailed mechanistic studies, representing potential new virulence determinants. For example, several sugar metabolism proteins were differentially regulated in response to lower calcium and higher temperature, suggesting these proteins, while not directly connected to virulence, either represent a metabolic switch for survival in the host environment or may facilitate production of virulence factors. Results presented here contribute to a more thorough understanding of the virulence mechanism of Y. pestis through proteomic characterization of the pathogen under induced virulence.« less

Probable transmission of Yersinia enterocolitica from a pet dog with diarrhoea to a 1-year-old infant.

PubMed

Hetem, D J; Pekelharing, M; Thijsen, S F T

2013-08-16

We report a highly probable case of transmission of a Yersinia enterocolitica from a pet puppy dog, adopted from a Spanish asylum, to a 1-year-old girl. After several weeks of diarrhoea, a PCR detecting enteropathogenic bacteria was performed on the faeces, revealing Y enterocolitica. Following cultures yielded a Y enterocolitica biotype 4, serotype O:3 in the faeces of the girl as well as puppy dog. Despite antibiotic treatment, symptoms and shedding of the organism in the faeces endured during a 2 month period.

Studies on a lipopolysaccharide-protein complex from Yersinia pseudotuberculosis. 1 isolation and characterization.

PubMed

Solov'eva, T F; Yermak, I M; Bondarenko, O D; Frolova, G M; Ovodov, Y S

1979-01-01

A comparative study of various procedures of a lipopolysaccharide-protein complex (LPPC) from Yersinia pseudotuberculosis was carried out. The materials obtained were fractionated by molecular-sieve chromatography on Sepharose 2B resulting in highly aggregated complexes with antigen activity. LPPC aggregates dissociated in the presence of sodium dodecylsulphate (SDS) and urea. The chemical composition and serologic properties of fractions obtained are under consideration. The protein component of the complex consists of two major polypeptides (molecular weights--45,000 and 20,000) and some minor ones. The LPS component appeared to give 2--3 narrow bands in gel under conditions of SDS-polyacrylamide gel electrophoresis. It is suggested that such fractionation is caused by LPS association-dissociation in the course of electrophoresis.

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.

Substrains of 129 Mice Are Resistant to Yersinia pestis KIM5: Implications for Interleukin-10-Deficient Mice▿

PubMed Central

Turner, Joshua K.; Xu, John L.; Tapping, Richard I.

2009-01-01

Interleukin-10 (IL-10)-deficient mice are resistant to several pathogens, including Yersinia pestis. Surprisingly, we observed that heterozygous IL-10+/− mice also survive high-dose intravenous infection with Y. pestis KIM5 (Pgm−). Analysis of commercial IL-10−/− mice revealed that at least 30 cM of genomic DNA from the original 129 strain remains, including a functional Slc11a1 (Nramp1) gene. Interestingly, two substrains of 129 mice were resistant to high-dose Y. pestis KIM5. Resistance does not appear to be recessive, as F1 mice (C57BL/6J × 129) also survived a high-dose challenge. A QTL-based genetic scan of chromosome 1 with 35 infected F1 backcrossed mice revealed that resistance to KIM5 maps to a region near IL-10. Two novel IL-10+/+ mouse strains which each possess most of the original 30-cM stretch of 129 DNA maintained resistance to high-dose infection with Y. pestis KIM5 even in a heterozygous state. Conversely, a novel IL-10−/− mouse strain in which most of the 129 DNA has been crossed out exhibited intermediate resistance to KIM5, while the corresponding IL-10+/− strain was completely susceptible. Taken together, these results demonstrate that 129-derived genomic DNA near IL-10 confers resistance to Yersinia pestis KIM5 and contributes to the observed resistance of IL-10−/− mice. PMID:18955473

Functional and structural analysis of a highly-expressed Yersinia pestis small RNA following infection of cultured macrophages

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

Li, Nan; Hennelly, Scott P.; Stubben, Chris J.

Non-coding small RNAs (sRNAs) are found in practically all bacterial genomes and play important roles in regulating gene expression to impact bacterial metabolism, growth, and virulence. We performed transcriptomics analysis to identify sRNAs that are differentially expressed in Yersinia pestis that invaded the human macrophage cell line THP-1, compared to pathogens that remained extracellular in the presence of host. Using ultra high-throughput sequencing, we identified 37 novel and 143 previously known sRNAs in Y. pestis. In particular, the sRNA Ysr170 was highly expressed in intracellular Yersinia and exhibited a log2 fold change ~3.6 higher levels compared to extracellular bacteria. Wemore » found that knock-down of Ysr170 expression attenuated infection efficiency in cell culture and growth rate in response to different stressors. In addition, we applied selective 2’-hydroxyl acylation analyzed by primer extension (SHAPE) analysis to determine the secondary structure of Ysr170 and observed structural changes resulting from interactions with the aminoglycoside antibiotic gentamycin and the RNA chaperone Hfq. Interestingly, gentamicin stabilized helix 4 of Ysr170, which structurally resembles the native gentamicin 16S ribosomal binding site. Lastly, we modeled the tertiary structure of Ysr170 binding to gentamycin using RNA motif modeling. Integration of these experimental and structural methods can provide further insight into the design of small molecules that can inhibit function of sRNAs required for pathogen virulence.« less

Functional and structural analysis of a highly-expressed Yersinia pestis small RNA following infection of cultured macrophages

DOE PAGES

Li, Nan; Hennelly, Scott P.; Stubben, Chris J.; ...

2016-12-28

Non-coding small RNAs (sRNAs) are found in practically all bacterial genomes and play important roles in regulating gene expression to impact bacterial metabolism, growth, and virulence. We performed transcriptomics analysis to identify sRNAs that are differentially expressed in Yersinia pestis that invaded the human macrophage cell line THP-1, compared to pathogens that remained extracellular in the presence of host. Using ultra high-throughput sequencing, we identified 37 novel and 143 previously known sRNAs in Y. pestis. In particular, the sRNA Ysr170 was highly expressed in intracellular Yersinia and exhibited a log2 fold change ~3.6 higher levels compared to extracellular bacteria. Wemore » found that knock-down of Ysr170 expression attenuated infection efficiency in cell culture and growth rate in response to different stressors. In addition, we applied selective 2’-hydroxyl acylation analyzed by primer extension (SHAPE) analysis to determine the secondary structure of Ysr170 and observed structural changes resulting from interactions with the aminoglycoside antibiotic gentamycin and the RNA chaperone Hfq. Interestingly, gentamicin stabilized helix 4 of Ysr170, which structurally resembles the native gentamicin 16S ribosomal binding site. Lastly, we modeled the tertiary structure of Ysr170 binding to gentamycin using RNA motif modeling. Integration of these experimental and structural methods can provide further insight into the design of small molecules that can inhibit function of sRNAs required for pathogen virulence.« less

Effects of host cell sterol composition upon internalization of Yersinia pseudotuberculosis and clustered β1 integrin.

PubMed

Kim, JiHyun; Fukuto, Hana S; Brown, Deborah A; Bliska, James B; London, Erwin

2018-01-26

Yersinia pseudotuberculosis is a foodborne pathogenic bacterium that causes acute gastrointestinal illness, but its mechanisms of infection are incompletely described. We examined how host cell sterol composition affected Y. pseudotuberculosis uptake. To do this, we depleted or substituted cholesterol in human MDA-MB-231 epithelial cells with various alternative sterols. Decreasing host cell cholesterol significantly reduced pathogen internalization. When host cell cholesterol was substituted with various sterols, only desmosterol and 7-dehydrocholesterol supported internalization. This specificity was not due to sterol dependence of bacterial attachment to host cells, which was similar with all sterols studied. Because a key step in Y. pseudotuberculosis internalization is interaction of the bacterial adhesins invasin and YadA with host cell β1 integrin, we compared the sterol dependence of wildtype Y. pseudotuberculosis internalization with that of Δ inv , Δ yadA , and Δ inv Δ yadA mutant strains. YadA deletion decreased bacterial adherence to host cells, whereas invasin deletion had no effect. Nevertheless, host cell sterol substitution had a similar effect on internalization of these bacterial deletion strains as on the wildtype bacteria. The Δ inv Δ yadA double mutant adhered least to cells and so was not significantly internalized. The sterol structure dependence of Y. pseudotuberculosis internalization differed from that of endocytosis, as monitored using antibody-clustered β1 integrin and previous studies on other proteins, which had a more permissive sterol dependence. This study suggests that agents could be designed to interfere with internalization of Yersinia without disturbing endocytosis. © 2018 by The American Society for Biochemistry and Molecular Biology, Inc.

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

Rapid and Sensitive Detection of Yersinia pestis Using Amplification of Plague Diagnostic Bacteriophages Monitored by Real-Time PCR

DTIC Science & Technology

2010-06-01

validation of real-time PCR assays for the identification of Yersinia pestis. Clin Chem Lab Med 46: 1239–1244. 25. Matero P, Pasanen T , Laukkanen R ...research was supported by the Defense Threat Reduction Agency, Joint Science and Technology Office, Medical S& T Division. The funders had no role in study...QA1122-F 59-CCAAATGGAAGCACTGCCCTGTAG-39 24 61.8 54.2 105 QA1122- R 59-ATGCGGTGAGAGCCTCAGGATTC-39 23 62.1 56.5 L-413C-F 59-ACGTGGTCATGTCCGTCACAATC-39 23

Comparative anatomy and histology of developmental and parasitic stages in the life cycle of the lined sea anemone Edwardsiella lineata.

PubMed

Reitzel, Adam M; Daly, Marymegan; Sullivan, James C; Finnerty, John R

2009-02-01

The evolution of parasitism is often accompanied by profound changes to the developmental program. However, relatively few studies have directly examined the developmental evolution of parasitic species from free-living ancestors. The lined sea anemone Edwardsiella lineata is a relatively recently evolved parasite for which closely related free-living outgroups are known, including the starlet sea anemone Nematostella vectensis. The larva of E. lineata parasitizes the ctenophore Mnemiopsis leidyi, and, once embedded in its host, the anemone assumes a novel vermiform body plan. That we might begin to understand how the developmental program of this species has been transformed during the evolution of parasitism, we characterized the gross anatomy, histology, and cnidom of the parasitic stage, post-parasitic larval stage, and adult stage of the E. lineata life cycle. The distinct parasitic stage of the life cycle differs from the post-parasitic larva with respect to overall shape, external ciliation, cnida frequency, and tissue architecture. The parasitic stage and planula both contain holotrichs, a type of cnida not previously reported in Edwardsiidae. The internal morphology of the post-parasitic planula is extremely similar to the adult morphology, with a complete set of mesenterial tissue and musculature despite this stage having little external differentiation. Finally, we observed 2 previously undocumented aspects of asexual reproduction in E. lineata: (1) the parasitic stage undergoes transverse fission via physal pinching, the first report of asexual reproduction in a pre-adult stage in the Edwardsiidae; and (2) the juvenile polyp undergoes transverse fission via polarity reversal, the first time this form of fission has been reported in E. lineata.

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.

Analysis of temperature-dependent changes in the metabolism of Yersinia pestis.

NASA Astrophysics Data System (ADS)

Navid, Ali; Almaas, Eivind

2008-03-01

The gram-negative bacterium Yersinia pestis is the aetiological agent of bubonic plague, a zoonotic infection that occurs through the bite of a flea. It has long been known that Y. pestis has different metabolic needs upon transition from the flea gut environment (26 C) to that of a mammalian host (37 C). To study this and other outstanding questions about metabolic function of Y. pestis, we used the available genomic, biochemical and physiological data to develop a constraint-based flux balance model of metabolism in the avirulent 91001 strain (biovar Mediaevalis) of this organism. Utilizing two sets of whole-genome DNA microarray expression data, we examined the system level changes that occur when Y. pestis acclimatizes to temperature shifts. Our results point to fundamental changes in its oxidative metabolism of sugars and use of amino acids, in particular that of arginine. This behavior is indicative of an inefficient metabolism that could be caused by adaptation to life in a nutrient rich environment.

Influence of extremely low frequency electromagnetic fields on growth performance, innate immune response, biochemical parameters and disease resistance in rainbow trout, Oncorhynchus mykiss.

PubMed

Nofouzi, Katayoon; Sheikhzadeh, Najmeh; Mohamad-Zadeh Jassur, Davood; Ashrafi-Helan, Javad

2015-06-01

The effects of extremely low frequency electromagnetic fields on rainbow trout growth performance, innate immunity and biochemical parameters were studied. Rainbow trout (17-18 g) were exposed to electromagnetic fields (15 Hz) at 0.01, 0.1, 0.5, 5 and 50 µT, for 1 h daily over period of 60 days. Growth performance of fish improved in different treatment groups, especially at 0.1, 0.5, 5 and 50 µT. Immunological parameters, specifically hemagglutinating titer, total antiprotease and α1-antiprotease levels in treatment groups, were also enhanced. Total protein and globulin contents in the serum of fish exposed to 0.1, 0.5, 5 and 50 µT were significantly higher than those in the control group. No significant differences were found in serum enzyme activities, namely aspartate aminotransferase and alanine aminotransferase of fish in all treatment groups. Conversely, alkaline phosphatase level decreased in fish exposed to 0.01 and 50 µT electromagnetic fields. Meanwhile, electromagnetic induction at 0.1, 0.5, 5 and 50 µT enhanced fish protection against Yersinia ruckeri. These results indicated that these specific electromagnetic fields had possible effects on growth performance, nonspecific immunity and disease resistance of rainbow trout.

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.

Human Anti-Plague Monoclonal Antibodies Protect Mice from Yersinia pestis in a Bubonic Plague Model

PubMed Central

Xiao, Xiaodong; Zhu, Zhongyu; Dankmeyer, Jennifer L.; Wormald, Michael M.; Fast, Randy L.; Worsham, Patricia L.; Cote, Christopher K.; Amemiya, Kei; Dimitrov, Dimiter S.

2010-01-01

Yersinia pestis is the etiologic agent of plague that has killed more than 200 million people throughout the recorded history of mankind. Antibiotics may provide little immediate relief to patients who have a high bacteremia or to patients infected with an antibiotic resistant strain of plague. Two virulent factors of Y. pestis are the capsid F1 protein and the low-calcium response (Lcr) V-protein or V-antigen that have been proven to be the targets for both active and passive immunization. There are mouse monoclonal antibodies (mAbs) against the F1- and V-antigens that can passively protect mice in a murine model of plague; however, there are no anti-Yersinia pestis monoclonal antibodies available for prophylactic or therapeutic treatment in humans. We identified one anti-F1-specific human mAb (m252) and two anti-V-specific human mAb (m253, m254) by panning a naïve phage-displayed Fab library against the F1- and V-antigens. The Fabs were converted to IgG1s and their binding and protective activities were evaluated. M252 bound weakly to peptides located at the F1 N-terminus where a protective mouse anti-F1 mAb also binds. M253 bound strongly to a V-antigen peptide indicating a linear epitope; m254 did not bind to any peptide from a panel of 53 peptides suggesting that its epitope may be conformational. M252 showed better protection than m253 and m254 against a Y, pestis challenge in a plague mouse model. A synergistic effect was observed when the three antibodies were combined. Incomplete to complete protection was achieved when m252 was given at different times post-challenge. These antibodies can be further studied to determine their potential as therapeutics or prophylactics in Y. pestis infection in humans. PMID:20976274

Human anti-plague monoclonal antibodies protect mice from Yersinia pestis in a bubonic plague model.

PubMed

Xiao, Xiaodong; Zhu, Zhongyu; Dankmeyer, Jennifer L; Wormald, Michael M; Fast, Randy L; Worsham, Patricia L; Cote, Christopher K; Amemiya, Kei; Dimitrov, Dimiter S

2010-10-13

Yersinia pestis is the etiologic agent of plague that has killed more than 200 million people throughout the recorded history of mankind. Antibiotics may provide little immediate relief to patients who have a high bacteremia or to patients infected with an antibiotic resistant strain of plague. Two virulent factors of Y. pestis are the capsid F1 protein and the low-calcium response (Lcr) V-protein or V-antigen that have been proven to be the targets for both active and passive immunization. There are mouse monoclonal antibodies (mAbs) against the F1- and V-antigens that can passively protect mice in a murine model of plague; however, there are no anti-Yersinia pestis monoclonal antibodies available for prophylactic or therapeutic treatment in humans. We identified one anti-F1-specific human mAb (m252) and two anti-V-specific human mAb (m253, m254) by panning a naïve phage-displayed Fab library against the F1- and V-antigens. The Fabs were converted to IgG1s and their binding and protective activities were evaluated. M252 bound weakly to peptides located at the F1 N-terminus where a protective mouse anti-F1 mAb also binds. M253 bound strongly to a V-antigen peptide indicating a linear epitope; m254 did not bind to any peptide from a panel of 53 peptides suggesting that its epitope may be conformational. M252 showed better protection than m253 and m254 against a Y, pestis challenge in a plague mouse model. A synergistic effect was observed when the three antibodies were combined. Incomplete to complete protection was achieved when m252 was given at different times post-challenge. These antibodies can be further studied to determine their potential as therapeutics or prophylactics in Y. pestis infection in humans.

Yersinia enterocolitica: its isolation by cold enrichment from patients and healthy subjects.

PubMed Central

Van Noyen, R; Vandepitte, J; Wauters, G; Selderslaghs, R

1981-01-01

Routine culture and cold enrichment were compared in a prospective study on the isolation of Yersinia enterocolitica from patients with intestinal disease. Healthy controls were examined with the cold enrichment method only. Y enterocolitica was isolated from 5.9% of 1635 patient stools, 3.4% of 206 appendices, and 4.0% of 555 control stools. Serotypes 0:3 and 0:9 were eight times more prevalent in patients than in controls. Other serotypes were twice as prevalent in controls than in patients. Cold enrichment did not significantly increase the recovery of serotypes 0:3 and 0:9 in acute enteritis, but it was responsible for all isolates of the other serotypes. Evidence is presented that the other serotypes are not pathogenic. In patient stools, Y enterocolitica was demonstrated less frequently than Salmonella (9.1%), and more often than Campylobacter jejuni (1.8%) and Shigella (0.1%). PMID:7024325

Concerted Actions of a Thermo-labile Regulator and a Unique Intergenic RNA Thermosensor Control Yersinia Virulence

PubMed Central

Kortmann, Jens; Seekircher, Stephanie; Heroven, Ann Kathrin; Berger, Evelin; Pisano, Fabio; Thiermann, Tanja; Wolf-Watz, Hans; Narberhaus, Franz; Dersch, Petra

2012-01-01

Expression of all Yersinia pathogenicity factors encoded on the virulence plasmid, including the yop effector and the ysc type III secretion genes, is controlled by the transcriptional activator LcrF in response to temperature. Here, we show that a protein- and RNA-dependent hierarchy of thermosensors induce LcrF synthesis at body temperature. Thermally regulated transcription of lcrF is modest and mediated by the thermo-sensitive modulator YmoA, which represses transcription from a single promoter located far upstream of the yscW-lcrF operon at moderate temperatures. The transcriptional response is complemented by a second layer of temperature-control induced by a unique cis-acting RNA element located within the intergenic region of the yscW-lcrF transcript. Structure probing demonstrated that this region forms a secondary structure composed of two stemloops at 25°C. The second hairpin sequesters the lcrF ribosomal binding site by a stretch of four uracils. Opening of this structure was favored at 37°C and permitted ribosome binding at host body temperature. Our study further provides experimental evidence for the biological relevance of an RNA thermometer in an animal model. Following oral infections in mice, we found that two different Y. pseudotuberculosis patient isolates expressing a stabilized thermometer variant were strongly reduced in their ability to disseminate into the Peyer's patches, liver and spleen and have fully lost their lethality. Intriguingly, Yersinia strains with a destabilized version of the thermosensor were attenuated or exhibited a similar, but not a higher mortality. This illustrates that the RNA thermometer is the decisive control element providing just the appropriate amounts of LcrF protein for optimal infection efficiency. PMID:22359501

Prevalence, conservation and functional analysis of Yersinia and Escherichia CRISPR regions in clinical Pseudomonas aeruginosa isolates

PubMed Central

Cady, K. C.; White, A. S.; Hammond, J. H.; Abendroth, M. D.; Karthikeyan, R. S. G.; Lalitha, P.; Zegans, M. E.; O'Toole, G. A.

2011-01-01

Here, we report the characterization of 122 Pseudomonas aeruginosa clinical isolates from three distinct geographical locations: Dartmouth Hitchcock Medical Center in New Hampshire, USA, the Charles T. Campbell Eye Microbiology Lab at the University of Pittsburgh Medical Center, USA, and the Aravind Eye Hospital in Madurai, India. We identified and located clustered regularly interspaced short palindromic repeats (CRISPR) in 45/122 clinical isolates and sequenced these CRISPR, finding that Yersinia subtype CRISPR regions (33 %) were more prevalent than the Escherichia CRISPR region subtype (6 %) in these P. aeruginosa clinical isolates. Further, we observed 132 unique spacers from these 45 CRISPR that are 100 % identical to prophages or sequenced temperate bacteriophage capable of becoming prophages. Most intriguingly, all of these 132 viral spacers matched to temperate bacteriophage/prophages capable of inserting into the host chromosome, but not to extrachromosomally replicating lytic P. aeruginosa bacteriophage. We next assessed the ability of the more prevalent Yersinia subtype CRISPR regions to mediate resistance to bacteriophage infection or lysogeny by deleting the entire CRISPR region from sequenced strain UCBPP-PA14 and six clinical isolates. We found no change in CRISPR-mediated resistance to bacteriophage infection or lysogeny rate even for CRISPR with spacers 100 % identical to a region of the infecting bacteriophage. Lastly, to show these CRISPR and cas genes were expressed and functional, we demonstrated production of small CRISPR RNAs. This work provides both the first examination to our knowledge of CRISPR regions within clinical P. aeruginosa isolates and a collection of defined CRISPR-positive and -negative strains for further CRISPR and cas gene studies. PMID:21081758

Concerted actions of a thermo-labile regulator and a unique intergenic RNA thermosensor control Yersinia virulence.

PubMed

Böhme, Katja; Steinmann, Rebekka; Kortmann, Jens; Seekircher, Stephanie; Heroven, Ann Kathrin; Berger, Evelin; Pisano, Fabio; Thiermann, Tanja; Wolf-Watz, Hans; Narberhaus, Franz; Dersch, Petra

2012-02-01

Expression of all Yersinia pathogenicity factors encoded on the virulence plasmid, including the yop effector and the ysc type III secretion genes, is controlled by the transcriptional activator LcrF in response to temperature. Here, we show that a protein- and RNA-dependent hierarchy of thermosensors induce LcrF synthesis at body temperature. Thermally regulated transcription of lcrF is modest and mediated by the thermo-sensitive modulator YmoA, which represses transcription from a single promoter located far upstream of the yscW-lcrF operon at moderate temperatures. The transcriptional response is complemented by a second layer of temperature-control induced by a unique cis-acting RNA element located within the intergenic region of the yscW-lcrF transcript. Structure probing demonstrated that this region forms a secondary structure composed of two stemloops at 25°C. The second hairpin sequesters the lcrF ribosomal binding site by a stretch of four uracils. Opening of this structure was favored at 37°C and permitted ribosome binding at host body temperature. Our study further provides experimental evidence for the biological relevance of an RNA thermometer in an animal model. Following oral infections in mice, we found that two different Y. pseudotuberculosis patient isolates expressing a stabilized thermometer variant were strongly reduced in their ability to disseminate into the Peyer's patches, liver and spleen and have fully lost their lethality. Intriguingly, Yersinia strains with a destabilized version of the thermosensor were attenuated or exhibited a similar, but not a higher mortality. This illustrates that the RNA thermometer is the decisive control element providing just the appropriate amounts of LcrF protein for optimal infection efficiency.

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.

Inheritance of the lysozyme inhibitor Ivy was an important evolutionary step by Yersinia pestis to avoid the host innate immune response.

PubMed

Derbise, Anne; Pierre, François; Merchez, Maud; Pradel, Elizabeth; Laouami, Sabrina; Ricard, Isabelle; Sirard, Jean-Claude; Fritz, Jill; Lemaître, Nadine; Akinbi, Henry; Boneca, Ivo G; Sebbane, Florent

2013-05-15

Yersinia pestis (the plague bacillus) and its ancestor, Yersinia pseudotuberculosis (which causes self-limited bowel disease), encode putative homologues of the periplasmic lysozyme inhibitor Ivy and the membrane-bound lysozyme inhibitor MliC. The involvement of both inhibitors in virulence remains subject to debate. Mutants lacking ivy and/or mliC were generated. We evaluated the mutants' ability to counter lysozyme, grow in serum, and/or counter leukocytes; to produce disease in wild-type, neutropenic, or lysozyme-deficient rodents; and to induce host inflammation. MliC was not required for lysozyme resistance and the development of plague. Deletion of ivy decreased Y. pestis' ability to counter lysozyme and polymorphonuclear neutrophils, but it did not affect the bacterium's ability to grow in serum or resist macrophages. Y. pestis lacking Ivy had attenuated virulence, unless animals were neutropenic or lysozyme deficient. The Ivy mutant induced inflammation to a degree similar to that of the parental strain. Last, Y. pseudotuberculosis did not require Ivy to counter lysozyme and for virulence. Ivy is required to counter lysozyme during infection, but its role as a virulence factor is species dependent. Our study also shows that a gene that is not necessary for the virulence of an ancestral bacterium may become essential in the emergence of a new pathogen.

A mutation in rcsB, a gene encoding the core component of the Rcs cascade, enhances the virulence of Edwardsiella tarda.

PubMed

Xu, Ying; Xu, Tingting; Wang, Bin; Dong, Xue; Sheng, Aibo; Zhang, Xiao-Hua

2014-04-01

Edwardsiella tarda, a Gram-negative bacterium of the family Enterobacteriaceae, is the causative agent of the systemic disease edwardsiellosis, which is a major problem in aquaculture industry worldwide. Many virulence-related genes in E. tarda have been investigated, but the Rcs phosphorelay, a two-component pathway, which regulates several cell-surface-associated structures related to invasion and survival in host cells, has not yet been thoroughly studied. In the present study, an rcsB in-frame deletion mutant ΔrcsB was constructed through double-crossover allelic exchange. To complement the rcsB mutation, the ΔrcsB (pACYC184K-rcsB) mutant was constructed by transformation of a low-copy plasmid carrying the intact rcsB into the ΔrcsB mutant of E. tarda. Several virulence-associated characters of the mutants and wild-type strain were tested. Compared with wild-type strain EIB202, biofilm formation decreased significantly in ΔrcsB, while ΔrcsB (pACYC184K-rcsB) recovered the phenotype to some extent. In addition, the capacity for autoagglutination, the percentage of adherence and internalization to Epithelioma papulosum cyprini cells and lethality toward zebrafish embryos significantly increased in ΔrcsB. All these phenomena displayed by mutant ΔrcsB showed a certain degree of recovery, though incomplete, in strain ΔrcsB (pACYC184K-rcsB). Present results indicate that rcsB is involved in regulating the gene expression of virulence factors in E. tarda, as shown in other members of Enterobacteriaceae. Copyright © 2014 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

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.

Na+/H+ antiport is essential for Yersinia pestis virulence.

PubMed

Minato, Yusuke; Ghosh, Amit; Faulkner, Wyatt J; Lind, Erin J; Schesser Bartra, Sara; Plano, Gregory V; Jarrett, Clayton O; Hinnebusch, B Joseph; Winogrodzki, Judith; Dibrov, Pavel; Häse, Claudia C

2013-09-01

Na(+)/H(+) antiporters are ubiquitous membrane proteins that play a central role in the ion homeostasis of cells. In this study, we examined the possible role of Na(+)/H(+) antiport in Yersinia pestis virulence and found that Y. pestis strains lacking the major Na(+)/H(+) antiporters, NhaA and NhaB, are completely attenuated in an in vivo model of plague. The Y. pestis derivative strain lacking the nhaA and nhaB genes showed markedly decreased survival in blood and blood serum ex vivo. Complementation of either nhaA or nhaB in trans restored the survival of the Y. pestis nhaA nhaB double deletion mutant in blood. The nhaA nhaB double deletion mutant also showed inhibited growth in an artificial serum medium, Opti-MEM, and a rich LB-based medium with Na(+) levels and pH values similar to those for blood. Taken together, these data strongly suggest that intact Na(+)/H(+) antiport is indispensable for the survival of Y. pestis in the bloodstreams of infected animals and thus might be regarded as a promising noncanonical drug target for infections caused by Y. pestis and possibly for those caused by other blood-borne bacterial pathogens.

[Evaluation of the protection efficiency of secretory antibodies in experimental Yersinia infection in guinea-pigs immunized with polyvalent vaccine against this infection].

PubMed

Pogorel'skiĭ, I P; Drobkov, V I

2009-01-01

The paper presents the results of experiments to elucidate the protection efficiency of secretory antibodies via parenteral and oral inoculation with pathogenic Yersinia in guinea pigs immunized with a polyvalent yersiniasis vaccine designed on the basis of the pseudotuberculosis microbial strain that synthesizes the F1 antigen of a plague microbe. Immunization of guinea pigs with the polyvalent yersiniasis vaccine protects experimental animals against pseudotuberculosis, intestinal yersiniasis, and plague infections.

Subcellular proteomic analysis of host-pathogen interactions using human monocytes exposed to Yersinia pestis and Yersinia pseudotuberculosis

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

Zhang, C G; Gonzales, A D; Choi, M W

2004-05-20

Yersinia pestis, the etiological agent of plague, is of concern to human health both from an infectious disease and a civilian biodefense perspective. While Y. pestis and Y. pseudotuberculosis share more than 90% DNA homology, they have significantly different clinical manifestations. Plague is often fatal if untreated, yet Y. pseudotuberculosis causes severe intestinal distress and is rarely fatal. A better understanding of host response to these closely related pathogens may help explain the different mechanisms of virulence and pathogenesis that result in such different clinical outcomes. The aim of this study was to characterize host protein expression changes in humanmore » monocyte-like U937 cells after exposure to Y. pestis and Y. pseudotuberculosis. In order to gain global proteomic coverage of host response, proteins from cytoplasmic, nuclear and membrane fractions of host cells were studied by 2-dimensional differential gel electrophoresis (2-D DIGE) and relative protein expression differences were quantitated. Differentially expressed proteins, with at least 1.5 fold expression changes and p values of 0.01 or less, were identified by MALDI-MS or LC/MS/MS. With these criteria, differential expression was detected in 16 human proteins after Y. pestis exposure and 13 human proteins after Y. pseudotuberculosis exposure, of which only two of the differentially expressed proteins identified were shared between the two exposures. Proteins identified in this study are reported to be involved in a wide spectrum of cellular functions and host defense mechanisms including apoptosis, cytoskeletal rearrangement, protein synthesis and degradation, DNA replication and transcription, metabolism, protein folding, and cell signaling. Notably, the differential expression patterns observed can distinguish the two pathogen exposures from each other and from unexposed host cells. The functions of the differentially expressed proteins identified provide insight on the

Yersinia pestis caf1 variants and the limits of plague vaccine protection.

PubMed

Quenee, Lauriane E; Cornelius, Claire A; Ciletti, Nancy A; Elli, Derek; Schneewind, Olaf

2008-05-01

Yersinia pestis, the highly virulent agent of plague, is a biological weapon. Strategies that prevent plague have been sought for centuries, and immunization with live, attenuated (nonpigmented) strains or subunit vaccines with F1 (Caf1) antigen is considered effective. We show here that immunization with live, attenuated strains generates plague-protective immunity and humoral immune responses against F1 pilus antigen and LcrV. Y. pestis variants lacking caf1 (F1 pili) are not only fully virulent in animal models of bubonic and pneumonic plague but also break through immune responses generated with live, attenuated strains or F1 subunit vaccines. In contrast, immunization with purified LcrV, a protein at the tip of type III needles, generates protective immunity against the wild-type and the fully virulent caf1 mutant strain, in agreement with the notion that LcrV can elicit vaccine protection against both types of virulent plague strains.

yadBC of Yersinia pestis, a new virulence determinant for bubonic plague.

PubMed

Forman, Stanislav; Wulff, Christine R; Myers-Morales, Tanya; Cowan, Clarissa; Perry, Robert D; Straley, Susan C

2008-02-01

In all Yersinia pestis strains examined, the adhesin/invasin yadA gene is a pseudogene, yet Y. pestis is invasive for epithelial cells. To identify potential surface proteins that are structurally and functionally similar to YadA, we searched the Y. pestis genome for open reading frames with homology to yadA and found three: the bicistronic operon yadBC (YPO1387 and YPO1388 of Y. pestis CO92; y2786 and y2785 of Y. pestis KIM5), which encodes two putative surface proteins, and YPO0902, which lacks a signal sequence and likely is nonfunctional. In this study we characterized yadBC regulation and tested the importance of this operon for Y. pestis adherence, invasion, and virulence. We found that loss of yadBC caused a modest loss of invasiveness for epithelioid cells and a large decrease in virulence for bubonic plague but not for pneumonic plague in mice.

Diverse Genotypes of Yersinia pestis Caused Plague in Madagascar in 2007.

PubMed

Riehm, Julia M; Projahn, Michaela; Vogler, Amy J; Rajerison, Minoaerisoa; Andersen, Genevieve; Hall, Carina M; Zimmermann, Thomas; Soanandrasana, Rahelinirina; Andrianaivoarimanana, Voahangy; Straubinger, Reinhard K; Nottingham, Roxanne; Keim, Paul; Wagner, David M; Scholz, Holger C

2015-06-01

Yersinia pestis is the causative agent of human plague and is endemic in various African, Asian and American countries. In Madagascar, the disease represents a significant public health problem with hundreds of human cases a year. Unfortunately, poor infrastructure makes outbreak investigations challenging. DNA was extracted directly from 93 clinical samples from patients with a clinical diagnosis of plague in Madagascar in 2007. The extracted DNAs were then genotyped using three molecular genotyping methods, including, single nucleotide polymorphism (SNP) typing, multi-locus variable-number tandem repeat analysis (MLVA), and Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) analysis. These methods provided increasing resolution, respectively. The results of these analyses revealed that, in 2007, ten molecular groups, two newly described here and eight previously identified, were responsible for causing human plague in geographically distinct areas of Madagascar. Plague in Madagascar is caused by numerous distinct types of Y. pestis. Genotyping method choice should be based upon the discriminatory power needed, expense, and available data for any desired comparisons. We conclude that genotyping should be a standard tool used in epidemiological investigations of plague outbreaks.

The responses of an anaerobic microorganism, Yersinia intermedia MASE-LG-1 to individual and combined simulated Martian stresses

PubMed Central

Bohmeier, Maria; Perras, Alexandra K.; Schwendner, Petra; Rabbow, Elke; Moissl-Eichinger, Christine; Cockell, Charles S.; Pukall, Rüdiger; Vannier, Pauline; Marteinsson, Viggo T.; Monaghan, Euan P.; Ehrenfreund, Pascale; Garcia-Descalzo, Laura; Gómez, Felipe; Malki, Moustafa; Amils, Ricardo; Gaboyer, Frédéric; Westall, Frances; Cabezas, Patricia; Walter, Nicolas; Rettberg, Petra

2017-01-01

The limits of life of aerobic microorganisms are well understood, but the responses of anaerobic microorganisms to individual and combined extreme stressors are less well known. Motivated by an interest in understanding the survivability of anaerobic microorganisms under Martian conditions, we investigated the responses of a new isolate, Yersinia intermedia MASE-LG-1 to individual and combined stresses associated with the Martian surface. This organism belongs to an adaptable and persistent genus of anaerobic microorganisms found in many environments worldwide. The effects of desiccation, low pressure, ionizing radiation, varying temperature, osmotic pressure, and oxidizing chemical compounds were investigated. The strain showed a high tolerance to desiccation, with a decline of survivability by four orders of magnitude during a storage time of 85 days. Exposure to X-rays resulted in dose-dependent inactivation for exposure up to 600 Gy while applied doses above 750 Gy led to complete inactivation. The effects of the combination of desiccation and irradiation were additive and the survivability was influenced by the order in which they were imposed. Ionizing irradiation and subsequent desiccation was more deleterious than vice versa. By contrast, the presence of perchlorates was not found to significantly affect the survival of the Yersinia strain after ionizing radiation. These data show that the organism has the capacity to survive and grow in physical and chemical stresses, imposed individually or in combination that are associated with Martian environment. Eventually it lost its viability showing that many of the most adaptable anaerobic organisms on Earth would be killed on Mars today. PMID:29069099

Immunological responses and disease resistance of rainbow trout (Oncorhynchus mykiss) juveniles following dietary administration of stinging nettle (Urtica dioica).

PubMed

Saeidi Asl, Mohammad Reza; Adel, Milad; Caipang, Christopher Marlowe A; Dawood, Mahmoud A O

2017-12-01

The present study investigated the effects of dietary supplementation of stinging nettle (Urtica dioica) on growth performance, skin mucus, immune response and disease resistance of rainbow trout (Oncorhynchus mykiss) fed with diets supplemented with U. dioica at 0, 1, 2 and 3%. After 8 weeks of feeding, the addition of U. dioica at 3% level resulted in improved weight gain, specific growth rate and feed conversion ratio significantly when compared to the other groups (P < 0.05). Hematological responses including: hematocrit (Htc), hemoglobin (Hb), lymphocyte and neutrophil populations enhanced significantly in fish fed 3% of stinging nettle when measured after 4 weeks; while, total red blood cells, white blood, Htc, Hb, lymphocyte and neutrophil populations significantly increased after 8 weeks in the same group (P < 0.05). Total serum protein and glucose contents increased significantly in fish fed stinging nettle at 3% when compared to the other groups after 8 weeks; however, triglycerides decreased significantly in the same group on the 4th and 8th week (P < 0.05). Additionally, several immune parameters, namely, IgM, lysozyme, complement components C3 and C4, and respiratory burst of blood leukocytes significantly increased in the 3% fed group on the 4th week; while, after 8 weeks the immune responses enhanced in fish fed 2 and 3% diets (P < 0.05). At the end of the feeding trial, mucus samples obtained from the fish fed stinging nettle supplementation exhibited improved antagonistic activities against several bacterial pathogens (Streptococcus iniae, Yersinia ruckeri, Vibrio anguillarum and Lactococcus garviae), skin mucus enzymes activities (alkaline phosphatase, lysozyme, protease and esterase) and protein levels in 2 and 3% groups with the highest being in case of 3% group when compared to the other groups (P < 0.05). The cumulative mortality of rainbow trout subjected to Y. ruckeri infectious exhibited relatively low mortality levels in all

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.

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

Protein abundances can distinguish between naturally-occurring and laboratory strains of Yersinia pestis, the causative agent of plague

DOE PAGES

Merkley, Eric D.; Sego, Landon H.; Lin, Andy; ...

2017-08-30

Adaptive processes in bacterial species can occur rapidly in laboratory culture, leading to genetic divergence between naturally occurring and laboratory-adapted strains. Differentiating wild and closely-related laboratory strains is clearly important for biodefense and bioforensics; however, DNA sequence data alone has thus far not provided a clear signature, perhaps due to lack of understanding of how diverse genome changes lead to adapted phenotypes. Protein abundance profiles from mass spectrometry-based proteomics analyses are a molecular measure of phenotype. Proteomics data contains sufficient information that powerful statistical methods can uncover signatures that distinguish wild strains of Yersinia pestis from laboratory-adapted strains.

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

Environmental drivers of Yersinia pestis - a holistic perspective on Medieval Europe

NASA Astrophysics Data System (ADS)

Buentgen, U.

2009-09-01

Recent studies have indicated some evidence for a link between climate variability and plague (Yersinia pestis) dynamics in Central Asia and during most of the 20th century. An intensification of plague outbreaks via population peaks in its host-species, the great gerbil (Rhombomys opimus) and its fleas (Xenopsylla spp) has been found to occur during periods of warmer spring and wetter summer climate. This is important, as human epidemics of plague ultimately originate in its wildlife reservoirs. Given the fact that Medieval Europe was strongly devastated by the Black Death - the second pandemic after the Justinian plague ~540AD, and that the worldwide highest quality and quantity of climate proxy data exist for Europe, we here present, for the first time, a holistic approach to enhance understanding of the mid-14th century Black Death. This is of primary importance not only for medical/epidemiological research, but also for other scientific communities, because the Black Death disease had a sustainable impact on the socio-economic development, culture, art, and religion of Medieval Europe. Palaeoclimatic records of annually resolved European temperature and drought variability are compiled, a high-resolution time-series of anthropogenic deforestation is utilized, documentary archives of socio-economic relevance are considered, and the animal-born plague bacterium is placed in the ecological web. Considering the European/North Atlantic sector and the last millennium, periods of high solar radiation and reduced volcanic activity shift the North Atlantic Oscillation into a generally positive mode, yielding towards warmer temperatures and an intensification of the hydrological cycle. We now argue that increased internal circulation resulted in an overall wetter and warmer climate ~1350AD, which most likely was able to promote the prevalence of existing and widespread Yersinia pestis bacillus. Resulting outbreaks of bubonic plague could have been also supported by the

No evidence of deer mouse involvement in plague (Yersinia pestis) epizootics in prairie dogs.

PubMed

Salkeld, Daniel J; Stapp, Paul

2008-06-01

Plague, the disease caused by the bacterium Yersinia pestis, can have devastating impacts on black-tailed prairie dog (Cynomys ludovicianus) colonies. One suggested mechanism behind sporadic prairie dog die-offs involves an alternative mammal host, such as the deer mouse (Peromyscus maniculatus), which often inhabits prairie dog colonies. We examined the flea populations of deer mice to investigate the potential of flea-borne transmission of plague between deer mice and prairie dogs in northern Colorado, where plague is active in prairie dog colonies. Deer mice were predominantly infested with the flea Aetheca wagneri, and were rarely infested with prairie dog fleas, Oropsylla hirsuta. Likelihood of flea infestation increased with average monthly temperature, and flea loads were higher in reproductive animals. These results suggest that the deer mouse is an unlikely maintenance host of plague in this region.

Discerning Viable from Nonviable Yersinia pestis pgm- and Bacillus anthracis Sterne using Propidium Monoazide in the Presence of White Powders

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

Hess, Becky M.; Kaiser, Brooke LD; Sydor, Michael A.

ABSTRACT Aims To develop and optimize an assay to determine viability status of Bacillus anthracis Sterne and Yersinia pestis pgm- strains in the presence of white powders by coupling propidium monoazide (PMA) treatment with real-time PCR (qPCR) analysis. Methods and Results PMA selectively enters nonviable cells and binds DNA, thereby increasing qPCR assay cycle threshold (CT) values compared to untreated samples. Dye concentration, cell number and fitness, incubation time, inactivation methods, and assay buffer were optimized for B. anthracis Sterne and Y. pestis pgm-. Differences in CT values in nonviable cells compared to untreated samples were consistently > 9 formore » both B. anthracis Sterne vegetative cells and Y. pestis pgm- in the presence and absence of three different white powders. Our method eliminates the need for a DNA extraction step prior to detection by qPCR. Conclusions The developed assay enables simultaneous identification and viability assessment for B. anthracis Sterne and Y. pestis pgm- under laboratory conditions, even in the presence of white powders. Eliminating the DNA extraction step that is typically used reduces total assay time and labor requirements for sample analysis. Significance and Impact of the Study The method developed for simultaneous detection and viability assessment for B. anthracis and Y. pestis can be employed in forming decisions about the severity of a biothreat event or the safety of food. Keywords Bacillus anthracis, Yersinia pestis, Propidium Monoazide, qPCR, White Powders, Rapid Viability Detection« less

Yersinia pestis YopJ suppresses tumor necrosis factor alpha induction and contributes to apoptosis of immune cells in the lymph node but is not required for virulence in a rat model of bubonic plague.

PubMed

Lemaître, Nadine; Sebbane, Florent; Long, Daniel; Hinnebusch, B Joseph

2006-09-01

The virulence of the pathogenic Yersinia species depends on a plasmid-encoded type III secretion system that transfers six Yop effector proteins into host cells. One of these proteins, YopJ, has been shown to disrupt host cell signaling pathways involved in proinflammatory cytokine production and to induce macrophage apoptosis in vitro. YopJ-dependent apoptosis in mesenteric lymph nodes has also been demonstrated in a mouse model of Yersinia pseudotuberculosis infection. These results suggest that YopJ attenuates the host innate and adaptive immune response during infection, but the role of YopJ during bubonic plague has not been completely established. We evaluated the role of Yersinia pestis YopJ in a rat model of bubonic plague following intradermal infection with a fully virulent Y. pestis strain and an isogenic yopJ mutant. Deletion of yopJ resulted in a twofold decrease in the number of apoptotic immune cells in the bubo and a threefold increase in serum tumor necrosis factor alpha levels but did not result in decreased virulence, systemic spread, or colonization levels in the spleen and blood. Our results indicate that YopJ is not essential for bubonic plague pathogenesis, even after peripheral inoculation of low doses of Y. pestis. Instead, the effects of YopJ appear to overlap and augment the immunomodulatory effects of other Y. pestis virulence factors.

Expression profiling of Yersinia pestis during mouse pulmonary infection.

PubMed

Lawson, Jonathan N; Lyons, C Rick; Johnston, Stephen Albert

2006-11-01

Yersinia pestis, the causative agent of plague, can be transmitted by infected flea bite or inhaled aerosol. Both routes of infection have a high mortality rate, and pneumonic infections of Y. pestis represent a significant concern as a tool of bioterrorism. Understanding the transcriptional program of this pathogen during pulmonary infection should be valuable in understanding plague pathogenesis, as well as potentially offering insights into new vaccines and therapeutics. Toward this goal we developed a long oligonucleotide microarray to the plague bacillus and evaluated the expression profiles of Y. pestis in vitro and in the mouse pulmonary infection model in vivo. The in vitro analysis compared expression patterns at 27 versus 37 degrees C, as a surrogate of the transition from the flea to the mammalian host. The in vivo analysis used intranasal challenge to the mouse lung. By amplifying the Y. pestis RNA from individual mouse lungs we were able to map the transcriptional profile of plague at postinfection days 1 to 3. Our data present a very different transcriptional profile between in vivo and in vitro expression, suggesting Y. pestis responds to a variety of host signals during infection. Of note was the number of genes found in genomic regions with altered %GC content that are upregulated within the mouse lung environment. These data suggest these regions may provide particularly promising targets for both vaccines and therapeutics.

Comparative Ability of Oropsylla montana and Xenopsylla cheopis Fleas to Transmit Yersinia pestis by Two Different Mechanisms

PubMed Central

Bland, David M.; Bosio, Christopher F.; Jarrett, Clayton O.

2017-01-01

Background Transmission of Yersinia pestis by flea bite can occur by two mechanisms. After taking a blood meal from a bacteremic mammal, fleas have the potential to transmit the very next time they feed. This early-phase transmission resembles mechanical transmission in some respects, but the mechanism is unknown. Thereafter, transmission occurs after Yersinia pestis forms a biofilm in the proventricular valve in the flea foregut. The biofilm can impede and sometimes completely block the ingestion of blood, resulting in regurgitative transmission of bacteria into the bite site. In this study, we compared the relative efficiency of the two modes of transmission for Xenopsylla cheopis, a flea known to become completely blocked at a high rate, and Oropsylla montana, a flea that has been considered to rarely develop proventricular blockage. Methodology/Principal findings Fleas that took an infectious blood meal containing Y. pestis were maintained and monitored for four weeks for infection and proventricular blockage. The number of Y. pestis transmitted by groups of fleas by the two modes of transmission was also determined. O. montana readily developed complete proventricular blockage, and large numbers of Y. pestis were transmitted by that mechanism both by it and by X. cheopis, a flea known to block at a high rate. In contrast, few bacteria were transmitted in the early phase by either species. Conclusions A model system incorporating standardized experimental conditions and viability controls was developed to more reliably compare the infection, proventricular blockage and transmission dynamics of different flea vectors, and was used to resolve a long-standing uncertainty concerning the vector competence of O. montana. Both X. cheopis and O. montana are fully capable of transmitting Y. pestis by the proventricular biofilm-dependent mechanism. PMID:28081130

Adaptive strategies of Yersinia pestis to persist during inter-epizootic and epizootic periods

PubMed Central

Eisen, Rebecca J.; Gage, Kenneth L.

2009-01-01

Plague is a flea-borne zoonotic bacterial disease caused by Yersinia pestis. It has caused three historical pandemics, including the Black Death which killed nearly a third of Europe's population in the 14th century. In modern times, plague epizootics can extirpate entire susceptible wildlife populations and then disappear for long time periods. Understanding how Y. pestis is maintained during inter-epizootic periods and the factors responsible for transitioning to epizootics is important for preventing and controlling pathogen transmission and ultimately reducing the burden of human disease. In this review, we focus primarily on plague in North American foci and discuss the potential adaptive strategies Y. pestis might employ to ensure not only its survival during inter-epizootic periods but also the rapid epizootic spread and invasion of new territories that are so characteristic of plague and have resulted in major pandemics and establishment of plague foci throughout much of the world. PMID:18803931

Crystallization and preliminary X-ray diffraction analysis of FabG from Yersinia pestis.

PubMed

Nanson, Jeffrey David; Forwood, Jade Kenneth

2014-01-01

The type II fatty-acid biosynthesis pathway of bacteria provides enormous potential for antibacterial drug development owing to the structural differences between this and the type I fatty-acid biosynthesis system found in mammals. β-Ketoacyl-ACP reductase (FabG) is responsible for the reduction of the β-ketoacyl group linked to acyl carrier protein (ACP), and is essential for the formation of fatty acids and bacterial survival. Here, the cloning, expression, purification, crystallization and diffraction of FabG from Yersinia pestis (ypFabG), the highly virulent causative agent of plague, are reported. Recombinant FabG was expressed, purified to homogeneity and crystallized via the hanging-drop vapour-diffusion technique. Diffraction data were collected at the Australian Synchrotron to 2.30 Å resolution. The crystal displayed P2(1)2(1)2(1) symmetry, with unit-cell parameters a = 68.22, b = 98.68, c = 169.84 Å, and four ypFabG molecules in the asymmetric unit.

An Active Site Water Network in the Plasminogen Activator Pla from Yersinia pestis

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

Eren, Elif; Murphy, Megan; Goguen, Jon

2010-08-13

The plasminogen activator Pla from Yersinia pestis is an outer membrane protease (omptin) that is important for the virulence of plague. Here, we present the high-resolution crystal structure of wild-type, enzymatically active Pla at 1.9 {angstrom}. The structure shows a water molecule located between active site residues D84 and H208, which likely corresponds to the nucleophilic water. A number of other water molecules are present in the active site, linking residues important for enzymatic activity. The R211 sidechain in loop L4 is close to the nucleophilic water and possibly involved in the stabilization of the oxyanion intermediate. Subtle conformational changesmore » of H208 result from the binding of lipopolysaccharide to the outside of the barrel, explaining the unusual dependence of omptins on lipopolysaccharide for activity. The Pla structure suggests a model for the interaction with plasminogen substrate and provides a more detailed understanding of the catalytic mechanism of omptin proteases.« less

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.

The complete genome sequence and proteomics of Yersinia pestis phage Yep-phi.

PubMed

Zhao, Xiangna; Wu, Weili; Qi, Zhizhen; Cui, Yujun; Yan, Yanfeng; Guo, Zhaobiao; Wang, Zuyun; Wang, Hu; Deng, Haijun; Xue, Yan; Chen, Weijun; Wang, Xiaoyi; Yang, Ruifu

2011-01-01

Yep-phi, a lytic phage of Yersinia pestis, was isolated in China and is routinely used as a diagnostic phage for the identification of the plague pathogen. Yep-phi has an isometric hexagonal head containing dsDNA and a short non-contractile conical tail. In this study, we sequenced the Yep-phi genome (GenBank accession no. HQ333270) and performed proteomics analysis. The genome consists of 38 ,616 bp of DNA, including direct terminal repeats of 222 bp, and is predicted to contain 45 ORFs. Most structural proteins were identified by proteomics analysis. Compared with the three available genome sequences of lytic phages for Y. pestis, the phages could be divided into two subgroups. Yep-phi displays marked homology to the bacteriophages Berlin (GenBank accession no. AM183667) and Yepe2 (GenBank accession no. EU734170), and these comprise one subgroup. The other subgroup is represented by bacteriophage ΦA1122 (GenBank accession no. AY247822). Potential recombination was detected among the Yep-phi subgroup.

Yersinia pestis IS1541 transposition provides for escape from plague immunity.

PubMed

Cornelius, Claire A; Quenee, Lauriane E; Elli, Derek; Ciletti, Nancy A; Schneewind, Olaf

2009-05-01

Yersinia pestis is perhaps the most feared infectious agent due to its ability to cause epidemic outbreaks of plague disease in animals and humans with high mortality. Plague infections elicit strong humoral immune responses against the capsular antigen (fraction 1 [F1]) of Y. pestis, and F1-specific antibodies provide protective immunity. Here we asked whether Y. pestis generates mutations that enable bacterial escape from protective immunity and isolated a variant with an IS1541 insertion in caf1A encoding the F1 outer membrane usher. The caf1A::IS1541 insertion prevented assembly of F1 pili and provided escape from plague immunity via F1-specific antibodies without a reduction in virulence in mouse models of bubonic or pneumonic plague. F1-specific antibodies interfere with Y. pestis type III transport of effector proteins into host cells, an inhibitory effect that was overcome by the caf1A::IS1541 insertion. These findings suggest a model in which IS1541 insertion into caf1A provides for reversible changes in envelope structure, enabling Y. pestis to escape from adaptive immune responses and plague immunity.

Biomarker Candidate Identification in Yersinia Pestis Using Organism-Wide Semiquantitative Proteomics

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

Hixson, Kim K.; Adkins, Joshua N.; Baker, Scott E.

2006-11-03

Yersinia pestis, the causative agent of plague, is listed by the CDC as a level A select pathogen. To better enable detection, intervention and treatment of Y. pestis infections, it is necessary to understand its protein expression under conditions that promote or inhibit virulence. To this end, we have utilized a novel combination of the accurate mass and time tag methodology of mass spectrometry and clustering analysis using OmniViz™ to compare the protein abundance changes of 992 identified proteins under four growth conditions. Temperature and Ca2+ concentration were used to trigger virulence associated protein expression fundamental to the low calciummore » response. High-resolution liquid chromatography and electrospray ionization mass spectrometry were utilized to determine protein identity and abundance on the genome-wide level. The cluster analyses revealed, in a rapid visual platform, the reproducibility of the current method as well as relevant protein abundance changes of expected and novel proteins relating to a specific growth condition and sub-cellular location. Using this method, 89 proteins were identified as having a similar abundance change profile to 29 known virulence associated proteins, providing additional biomarker candidates for future detection and vaccine development strategies.« less

A prebiotic role of Ecklonia cava improves the mortality of Edwardsiella tarda-infected zebrafish models via regulating the growth of lactic acid bacteria and pathogen bacteria.

PubMed

Lee, WonWoo; Oh, Jae Young; Kim, Eun-A; Kang, Nalae; Kim, Kil-Nam; Ahn, Ginnae; Jeon, You-Jin

2016-07-01

In this study, the beneficial prebiotic roles of Ecklonia cava (E. cava, EC) were evaluated on the growth of lactic acid bacteria (LAB) and pathogen bacteria and the mortality of pathogen-bacteria infected zebrafish model. The result showed that the original E. cava (EC) led to the highest growth effects on three LABs (Lactobacillus brevis, L. brevis; Lactobacillus pentosus, L. pentosus; Lactobacillus plantarum; L. plantarum) and it was dose-dependent manners. Also, EC, its Celluclast enzymatic (ECC) and 100% ethanol extracts (ECE) showed the anti-bacterial activities on the fish pathogenic bacteria such as (Edwardsiella tarda; E. tarda, Streptococcus iniae; S. iniae, and Vibrio harveyi; V. harveyi). Interestingly, EC induced the higher production of the secondary metabolites from L. plantarum in MRS medium. The secondary metabolites produced by EC significantly inhibited the growth of pathogen bacteria. In further in vivo study, the co-treatment of EC and L. plantarum improved the growth and mortality of E. tarda-infected zebrafish as regulating the expression of inflammatory molecules such as iNOS and COX2. Taken together, our present study suggests that the EC plays an important role as a potential prebiotic and has a protective effect against the infection caused by E. tarda injection in zebrafish. Also, our conclusion from this evidence is that EC can be used and applied as a useful prebiotic. Copyright © 2016 Elsevier Ltd. All rights reserved.

Detection of Rickettsia felis, Rickettsia typhi, Bartonella Species and Yersinia pestis in Fleas (Siphonaptera) from Africa.

PubMed

Leulmi, Hamza; Socolovschi, Cristina; Laudisoit, Anne; Houemenou, Gualbert; Davoust, Bernard; Bitam, Idir; Raoult, Didier; Parola, Philippe

2014-10-01

Little is known about the presence/absence and prevalence of Rickettsia spp, Bartonella spp. and Yersinia pestis in domestic and urban flea populations in tropical and subtropical African countries. Fleas collected in Benin, the United Republic of Tanzania and the Democratic Republic of the Congo were investigated for the presence and identity of Rickettsia spp., Bartonella spp. and Yersinia pestis using two qPCR systems or qPCR and standard PCR. In Xenopsylla cheopis fleas collected from Cotonou (Benin), Rickettsia typhi was detected in 1% (2/199), and an uncultured Bartonella sp. was detected in 34.7% (69/199). In the Lushoto district (United Republic of Tanzania), R. typhi DNA was detected in 10% (2/20) of Xenopsylla brasiliensis, and Rickettsia felis was detected in 65% (13/20) of Ctenocephalides felis strongylus, 71.4% (5/7) of Ctenocephalides canis and 25% (5/20) of Ctenophthalmus calceatus calceatus. In the Democratic Republic of the Congo, R. felis was detected in 56.5% (13/23) of Ct. f. felis from Kinshasa, in 26.3% (10/38) of Ct. f. felis and 9% (1/11) of Leptopsylla aethiopica aethiopica from Ituri district and in 19.2% (5/26) of Ct. f. strongylus and 4.7% (1/21) of Echidnophaga gallinacea. Bartonella sp. was also detected in 36.3% (4/11) of L. a. aethiopica. Finally, in Ituri, Y. pestis DNA was detected in 3.8% (1/26) of Ct. f. strongylus and 10% (3/30) of Pulex irritans from the villages of Wanyale and Zaa. Most flea-borne infections are neglected diseases which should be monitored systematically in domestic rural and urban human populations to assess their epidemiological and clinical relevance. Finally, the presence of Y. pestis DNA in fleas captured in households was unexpected and raises a series of questions regarding the role of free fleas in the transmission of plague in rural Africa, especially in remote areas where the flea density in houses is high.

Clinical role for a superantigen in Yersinia pseudotuberculosis infection.

PubMed Central

Abe, J; Onimaru, M; Matsumoto, S; Noma, S; Baba, K; Ito, Y; Kohsaka, T; Takeda, T

1997-01-01

Yersinia pseudotuberculosis is an enteric pathogen that causes a variety of clinical symptoms in the human. Recently, we reported the production of a superantigen (Y. pseudotuberculosis-derived mitogen, YPM) by this organism and characterized the gene structure of ypm. To further study the potential pathogenic role of YPM in Y. pseudotuberculosis infection, we assayed IgG anti-YPM antibodies and T cell antigen receptor-Vbeta expression of the T cells in peripheral blood and in mesenteric lymph node in patients acutely infected with Y. pseudotuberculosis. 20 out of 33 patients (61%) had an elevated antibody titer compared with healthy controls (P = 0.0001). Patients with systemic symptoms such as lymphadenopathy, transient renal dysfunction, and arthritis had significantly higher titers of anti-YPM than patients with gastrointestinal tract symptoms alone. T cells bearing the Vbeta3 gene segment were significantly increased (P = 0.009) among acute phase patients compared with healthy children. During the convalescence phase of the illness, there was a reduction in the abnormal level of Vbeta3 T cells. Moreover, in the mesenteric lymph node, an elevated level of Vbeta3 T cells compared with peripheral blood and a sequence diversity in the junctional region of the T cell antigen receptor beta-chain containing Vbeta3 element was observed in one patient. Together, these findings suggest that YPM was produced in vivo and played an important role in the pathogenesis of Y. pseudotuberculosis infection. PMID:9109426

Distinct clones of Yersinia pestis caused the black death.

PubMed

Haensch, Stephanie; Bianucci, Raffaella; Signoli, Michel; Rajerison, Minoarisoa; Schultz, Michael; Kacki, Sacha; Vermunt, Marco; Weston, Darlene A; Hurst, Derek; Achtman, Mark; Carniel, Elisabeth; Bramanti, Barbara

2010-10-07

From AD 1347 to AD 1353, the Black Death killed tens of millions of people in Europe, leaving misery and devastation in its wake, with successive epidemics ravaging the continent until the 18(th) century. The etiology of this disease has remained highly controversial, ranging from claims based on genetics and the historical descriptions of symptoms that it was caused by Yersinia pestis to conclusions that it must have been caused by other pathogens. It has also been disputed whether plague had the same etiology in northern and southern Europe. Here we identified DNA and protein signatures specific for Y. pestis in human skeletons from mass graves in northern, central and southern Europe that were associated archaeologically with the Black Death and subsequent resurgences. We confirm that Y. pestis caused the Black Death and later epidemics on the entire European continent over the course of four centuries. Furthermore, on the basis of 17 single nucleotide polymorphisms plus the absence of a deletion in glpD gene, our aDNA results identified two previously unknown but related clades of Y. pestis associated with distinct medieval mass graves. These findings suggest that plague was imported to Europe on two or more occasions, each following a distinct route. These two clades are ancestral to modern isolates of Y. pestis biovars Orientalis and Medievalis. Our results clarify the etiology of the Black Death and provide a paradigm for a detailed historical reconstruction of the infection routes followed by this disease.

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...

In vitro activities of 14 antibiotics against 100 human isolates of Yersinia pestis from a southern African plague focus.

PubMed Central

Frean, J A; Arntzen, L; Capper, T; Bryskier, A; Klugman, K P

1996-01-01

A limited repertoire of antimicrobial agents is currently in use for the treatment of plague. We investigated the in vitro activities of some newer antimicrobial agents against Yersinia pestis. Among the injectable agents tested, cefotaxime was the most active, and among the oral agents, both levofloxacin and ofloxacin were highly active, with MICs at which 90% of isolates are inhibited of < 0.03 microgram/ml. the susceptibilities to the ketolide RU004 and the penem faropenem warrant attention. The enhanced activities of quinolones against Y. pestis suggest that these agents should be further investigated for the treatment of human plague in the future. PMID:8913481

Protection of mice from fatal bubonic and pneumonic plague by passive immunization with monoclonal antibodies against the F1 protein of Yersinia pestis.

PubMed

Anderson, G W; Worsham, P L; Bolt, C R; Andrews, G P; Welkos, S L; Friedlander, A M; Burans, J P

1997-04-01

Monoclonal antibodies (MAbs) to the fraction 1 (F1) protein of Yersinia pestis protected mice against fatal pneumonic as well as bubonic plague from wild-type F1+ organisms. The rare isolation of a virulent F1- isolate from surviving animals supports earlier studies suggesting that improved vaccines should consist of immunogens to protect against F1- variants. The high degree of protection with IgG MAb suggests that secretory IgA is not required for protection from pneumonic plague.

Cell-mediated immune response and Th/Th cytokine profile of B-T constructs of F1 and V antigen of Yersinia pestis.

PubMed

Gupta, G; Khan, A A; Rao, D N

2010-03-01

Yersinia pestis, a Gram-negative bacterium, is the etiological agent of pneumonic and bubonic plague and still active in various regions of the world. Because plague is highly infectious and can readily spread by aerosolization, it poses a bioterrorism threat. The effective induction of mucosal as well as systemic immunity is an important attribute of an improved vaccine for plague. An alternative approach described here is the use of protective epitopes derived from immunodominant antigens (F1 and V) of Yersinia pestis. As T-cell immunity is also a major contributor of protection, microencapsulated B-T constructs of F1 and V antigen were used to immunize outbred and inbred mice through intranasal route, and lympho-proliferative response and cytokine profile of both Th(1) and Th(2) arms were measured in spleen, lamina propria and Peyer's patches. Three B-T constructs of F1 antigen and seven of V antigen showed significantly high T-cell response in terms of inducing systemic as well as mucosal response when compared to constituent peptides. These ten conjugates showed Th(1) cytokine profile whereas rest of the conjugates showed mixed Th(1)/Th(2) response. Four conjugates of V antigen showed high level of IL-10 production. In present study, microencapsulated B-T constructs after intranasal immunization generated systemic as well as mucosal immune response in all three sites, which offers an alternative approach for plague vaccine.

Fibrin facilitates both innate and T cell-mediated defense against Yersinia pestis.1

PubMed Central

Luo, Deyan; Lin, Shiuan; Parent, Michelle A.; Kanevsky, Isis Mullarky; Szaba, Frank M.; Kummer, Lawrence W.; Duso, Debra K.; Tighe, Michael; Hill, Jim; Gruber, Andras; Mackman, Nigel; Gailani, David; Smiley, Stephen T.

2013-01-01

The gram-negative bacterium Yersinia pestis causes plague, a rapidly progressing and often fatal disease. The formation of fibrin at sites of Y. pestis infection supports innate host defense against plague, perhaps by providing a non-diffusible spatial cue that promotes the accumulation of inflammatory cells expressing fibrin-binding integrins. This report demonstrates that fibrin is an essential component of T cell-mediated defense against plague but can be dispensable for antibody-mediated defense. Genetic or pharmacologic depletion of fibrin abrogated innate and T cell-mediated defense in mice challenged intranasally with Y. pestis. The fibrin-deficient mice displayed reduced survival, increased bacterial burden, and exacerbated hemorrhagic pathology. They also showed fewer neutrophils within infected lung tissue and reduced neutrophil viability at sites of liver infection. Depletion of neutrophils from wild type mice weakened T cell-mediated defense against plague. The data suggest that T cells combat plague in conjunction with neutrophils, which require help from fibrin in order to withstand Y. pestis encounters and effectively clear bacteria. PMID:23487423

Plague vaccines and the molecular basis of immunity against Yersinia pestis.

PubMed

Quenee, Lauriane E; Schneewind, Olaf

2009-12-01

Yersinia pestis is the causative agent of bubonic and pneumonic plague, human diseases with high mortality. Due to the microbe's ability to spread rapidly, plague epidemics present a serious public health threat. A search for prophylactic measures was initially based on historical reports of bubonic plague survivors and their apparent immunity. Due to safety and efficacy concerns, killed whole-cell preparations or live-attenuated plague vaccines are no longer considered in the United States. Vaccine developers have focused on specific subunits of plague bacteria. LcrV, a protein at the tip of type III secretion needles, and F1, the capsular pilus antigen, are both recognized as plague protective antigens. Antibodies against LcrV and F1 interfere with Y. pestis type III injection of host cells. While LcrV is absolutely essential for Y. pestis virulence, expression of F1 is dispensable for plague pathogenesis in small animals, non-human primates and presumably also in humans. Several subunit vaccines, for example rF1+rV (rYP002), rF1V or rV10, are being developed to generate plague protection in humans. Efficacy testing and licensure for human use requires the establishment of correlates for plague immunity.

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.

[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.

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.

The crystal structure of the Yersinia pestis iron chaperone YiuA reveals a basic triad binding motif for the chelated metal

PubMed Central

2017-01-01

Biological chelating molecules called siderophores are used to sequester iron and maintain its ferric state. Bacterial substrate-binding proteins (SBPs) bind iron–siderophore complexes and deliver these complexes to ATP-binding cassette (ABC) transporters for import into the cytoplasm, where the iron can be transferred from the siderophore to catalytic enzymes. In Yersinia pestis, the causative agent of plague, the Yersinia iron-uptake (Yiu) ABC transporter has been shown to improve iron acquisition under iron-chelated conditions. The Yiu transporter has been proposed to be an iron–siderophore transporter; however, the precise siderophore substrate is unknown. Therefore, the precise role of the Yiu transporter in Y. pestis survival remains uncharacterized. To better understand the function of the Yiu transporter, the crystal structure of YiuA (YPO1310/y2875), an SBP which functions to present the iron–siderophore substrate to the transporter for import into the cytoplasm, was determined. The 2.20 and 1.77 Å resolution X-ray crystal structures reveal a basic triad binding motif at the YiuA canonical substrate-binding site, indicative of a metal-chelate binding site. Structural alignment and computational docking studies support the function of YiuA in binding chelated metal. Additionally, YiuA contains two mobile helices, helix 5 and helix 10, that undergo 2–3 Å shifts across crystal forms and demonstrate structural breathing of the c-clamp architecture. The flexibility in both c-clamp lobes suggest that YiuA substrate transfer resembles the Venus flytrap mechanism that has been proposed for other SBPs. PMID:29095164

Eighteenth century Yersinia pestis genomes reveal the long-term persistence of an historical plague focus.

PubMed

Bos, Kirsten I; Herbig, Alexander; Sahl, Jason; Waglechner, Nicholas; Fourment, Mathieu; Forrest, Stephen A; Klunk, Jennifer; Schuenemann, Verena J; Poinar, Debi; Kuch, Melanie; Golding, G Brian; Dutour, Olivier; Keim, Paul; Wagner, David M; Holmes, Edward C; Krause, Johannes; Poinar, Hendrik N

2016-01-21

The 14th-18th century pandemic of Yersinia pestis caused devastating disease outbreaks in Europe for almost 400 years. The reasons for plague's persistence and abrupt disappearance in Europe are poorly understood, but could have been due to either the presence of now-extinct plague foci in Europe itself, or successive disease introductions from other locations. Here we present five Y. pestis genomes from one of the last European outbreaks of plague, from 1722 in Marseille, France. The lineage identified has not been found in any extant Y. pestis foci sampled to date, and has its ancestry in strains obtained from victims of the 14th century Black Death. These data suggest the existence of a previously uncharacterized historical plague focus that persisted for at least three centuries. We propose that this disease source may have been responsible for the many resurgences of plague in Europe following the Black Death.

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.

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.

[Determination of genetic bases of auxotrophy in Yersinia pestis ssp. caucasica strains].

PubMed

Odinokov, G N; Eroshenko, G A; Kukleva, L M; Shavina, N Iu; Krasnov, Ia M; Kutyrev, V V

2012-04-01

Based on the results of computer analysis of nucleotide sequences in strains Yersinia pestis and Y. pseudotuberculosis recorded in the files of NCBI GenBank database, differences between genes argA, aroG, aroF, thiH, and thiG of strain Pestoides F (subspecies caucasica) were found, compared to other strains of plaque agent and pseudotuberculosis microbe. Using PCR with calculated primers and the method of sequence analysis, the structure of variable regions of these genes was studied in 96 natural Y. pestis and Y. pseudotuberculosis strains. It was shown that all examined strains of subspecies caucasica, unlike strains of plague-causing agent of other subspecies and pseudotubercolosis microbe, had identical mutations in genes argA (integration of the insertion sequence IS100), aroG (insertion of ten nucleotides), aroF (inserion of IS100), thiH (insertion of nucleotide T), and thiG (deletion of 13 nucleotides). These mutations are the reason for the absence in strains belonging to this subspecies of the ability to synthesize arginine, phenylalanine, tyrosine, and vitamin B1 (thiamine), and cause their auxotrophy for these growth factors.

Thrombin-activatable fibrinolysis inhibitor is degraded by Salmonella enterica and Yersinia pestis.

PubMed

Valls Serón, M; Haiko, J; DE Groot, P G; Korhonen, T K; Meijers, J C M

2010-10-01

 Pathogenic bacteria modulate the host coagulation system to evade immune responses or to facilitate dissemination through extravascular tissues. In particular, the important bacterial pathogens Salmonella enterica and Yersinia pestis intervene with the plasminogen/fibrinolytic system. Thrombin-activatable fibrinolysis inhibitor (TAFI) has anti-fibrinolytic properties as the active enzyme (TAFIa) removes C-terminal lysine residues from fibrin, thereby attenuating accelerated plasmin formation.  Here, we demonstrate inactivation and cleavage of TAFI by homologous surface proteases, the omptins Pla of Y. pestis and PgtE of S. enterica. We show that omptin-expressing bacteria decrease TAFI activatability by thrombin-thrombomodulin and that the anti-fibrinolytic potential of TAFIa was reduced by recombinant Escherichia coli expressing Pla or PgtE. The functional impairment resulted from C-terminal cleavage of TAFI by the omptins.  Our results indicate that TAFI is degraded directly by the omptins PgtE of S. enterica and Pla of Y. pestis. This may contribute to the ability of PgtE and Pla to damage tissue barriers, such as fibrin, and thereby to enhance spread of S. enterica and Y. pestis during infection. © 2010 International Society on Thrombosis and Haemostasis.

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.

Survival and growth of Yersinia enterocolitica strains inoculated in skimmed milk treated with high hydrostatic pressure.

PubMed

De Lamo-Castellví, Sílvia; Roig-Sagués, Artur X; Capellas, Marta; Hernández-Herrero, Manuela; Guamis, Buenaventura

2005-07-25

Four human pathogenic strains of Yersinia enterocolitica (serotypes O:1, O:3, O:8, and O:9) were inoculated (7-8 log CFU/ml) in UHT skimmed milk and treated at 300, 400, and 500 MPa for 10 min at 20 degrees C, and then kept at 8 degrees C to assess their evolution for 15 days. Treatments at 400 and 500 MPa caused the highest lethality, generally reaching counts below detection level (1 CFU/ml) in the culture media. At 300 MPa, the most baroresistant serotypes were O:3 and O:8. After 15 days of storage at 8 degrees C, Y. enterocolitica showed growth over 8 log (CFU/ml) in all treatments. Kinetic study of microbial inactivation in skimmed milk was performed with serotype O:8 at 300 MPa, showing a tailing after 35 min of pressure treatment.

Yersinia pestis subverts the dermal neutrophil response in a mouse model of bubonic plague.

PubMed

Shannon, Jeffrey G; Hasenkrug, Aaron M; Dorward, David W; Nair, Vinod; Carmody, Aaron B; Hinnebusch, B Joseph

2013-08-27

The majority of human Yersinia pestis infections result from introduction of bacteria into the skin by the bite of an infected flea. Once in the dermis, Y. pestis can evade the host's innate immune response and subsequently disseminate to the draining lymph node (dLN). There, the pathogen replicates to large numbers, causing the pathognomonic bubo of bubonic plague. In this study, several cytometric and microscopic techniques were used to characterize the early host response to intradermal (i.d.) Y. pestis infection. Mice were infected i.d. with fully virulent or attenuated strains of dsRed-expressing Y. pestis, and tissues were analyzed by flow cytometry. By 4 h postinfection, there were large numbers of neutrophils in the infected dermis and the majority of cell-associated bacteria were associated with neutrophils. We observed a significant effect of the virulence plasmid (pCD1) on bacterial survival and neutrophil activation in the dermis. Intravital microscopy of i.d. Y. pestis infection revealed dynamic interactions between recruited neutrophils and bacteria. In contrast, very few bacteria interacted with dendritic cells (DCs), indicating that this cell type may not play a major role early in Y. pestis infection. Experiments using neutrophil depletion and a CCR7 knockout mouse suggest that dissemination of Y. pestis from the dermis to the dLN is not dependent on neutrophils or DCs. Taken together, the results of this study show a very rapid, robust neutrophil response to Y. pestis in the dermis and that the virulence plasmid pCD1 is important for the evasion of this response. Yersinia pestis remains a public health concern today because of sporadic plague outbreaks that occur throughout the world and the potential for its illegitimate use as a bioterrorism weapon. Since bubonic plague pathogenesis is initiated by the introduction of Y. pestis into the skin, we sought to characterize the response of the host's innate immune cells to bacteria early after

Isothiazolidinone (IZD) as a phosphoryl mimetic in inhibitors of the Yersinia pestis protein tyrosine phosphatase YopH

PubMed Central

Kim, Sung-Eun; Bahta, Medhanit; Lountos, George T.; Ulrich, Robert G.; Burke, Terrence R.; Waugh, David S.

2011-01-01

Isothiazolidinone (IZD) heterocycles can act as effective components of protein tyrosine phosphatase (PTP) inhibitors by simultaneously replicating the binding interactions of both a phosphoryl group and a highly conserved water molecule, as exemplified by the structures of several PTP1B–inhibitor complexes. In the first unambiguous demonstration of IZD interactions with a PTP other than PTP1B, it is shown by X-ray crystallography that the IZD motif binds within the catalytic site of the Yersinia pestis PTP YopH by similarly displacing a highly conserved water molecule. It is also shown that IZD-based bidentate ligands can inhibit YopH in a nonpromiscuous fashion at low micromolar concentrations. Hence, the IZD moiety may represent a useful starting point for the development of YopH inhibitors. PMID:21697602

Prevalence and abundance of fleas in black-tailed prairie dog burrows: implications for the transmission of plague (Yersinia pestis).

PubMed

Salkeld, Dan J; Stapp, Paul

2008-06-01

Plague, the disease caused by the bacterium Yersinia pestis, can have devastating impacts on North American wildlife. Epizootics, or die-offs, in prairie dogs (Cynomys ludovicianus) occur sporadically and fleas (Siphonaptera) are probably important in the disease's transmission and possibly as maintenance hosts of Y. pestis between epizootics. We monitored changes in flea abundance in prairie dog burrows in response to precipitation, temperature, and plague activity in shortgrass steppe in northern Colorado. Oropsylla hirsuta was the most commonly found flea, and it increased in abundance with temperature. In contrast, Oropsylla tuberculata cynomuris declined with rising temperature. During plague epizootics, flea abundance in burrows increased and then subsequently declined after the extirpation of their prairie dog hosts.

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.

Analysis of 3800-year-old Yersinia pestis genomes suggests Bronze Age origin for bubonic plague.

PubMed

Spyrou, Maria A; Tukhbatova, Rezeda I; Wang, Chuan-Chao; Valtueña, Aida Andrades; Lankapalli, Aditya K; Kondrashin, Vitaly V; Tsybin, Victor A; Khokhlov, Aleksandr; Kühnert, Denise; Herbig, Alexander; Bos, Kirsten I; Krause, Johannes

2018-06-08

The origin of Yersinia pestis and the early stages of its evolution are fundamental subjects of investigation given its high virulence and mortality that resulted from past pandemics. Although the earliest evidence of Y. pestis infections in humans has been identified in Late Neolithic/Bronze Age Eurasia (LNBA 5000-3500y BP), these strains lack key genetic components required for flea adaptation, thus making their mode of transmission and disease presentation in humans unclear. Here, we reconstruct ancient Y. pestis genomes from individuals associated with the Late Bronze Age period (~3800 BP) in the Samara region of modern-day Russia. We show clear distinctions between our new strains and the LNBA lineage, and suggest that the full ability for flea-mediated transmission causing bubonic plague evolved more than 1000 years earlier than previously suggested. Finally, we propose that several Y. pestis lineages were established during the Bronze Age, some of which persist to the present day.

Eighteenth century Yersinia pestis genomes reveal the long-term persistence of an historical plague focus

PubMed Central

Bos, Kirsten I; Herbig, Alexander; Sahl, Jason; Waglechner, Nicholas; Fourment, Mathieu; Forrest, Stephen A; Klunk, Jennifer; Schuenemann, Verena J; Poinar, Debi; Kuch, Melanie; Golding, G Brian; Dutour, Olivier; Keim, Paul; Wagner, David M; Holmes, Edward C; Krause, Johannes; Poinar, Hendrik N

2016-01-01

The 14th–18th century pandemic of Yersinia pestis caused devastating disease outbreaks in Europe for almost 400 years. The reasons for plague’s persistence and abrupt disappearance in Europe are poorly understood, but could have been due to either the presence of now-extinct plague foci in Europe itself, or successive disease introductions from other locations. Here we present five Y. pestis genomes from one of the last European outbreaks of plague, from 1722 in Marseille, France. The lineage identified has not been found in any extant Y. pestis foci sampled to date, and has its ancestry in strains obtained from victims of the 14th century Black Death. These data suggest the existence of a previously uncharacterized historical plague focus that persisted for at least three centuries. We propose that this disease source may have been responsible for the many resurgences of plague in Europe following the Black Death. DOI: http://dx.doi.org/10.7554/eLife.12994.001 PMID:26795402

Electrophoretic characterisation of the outer membrane proteins of Yersinia pestis isolated in north-east Brazil.

PubMed Central

Abath, F. G.; Almeida, A. M.; Ferreira, L. C.

1989-01-01

The outer membrane proteins of 38 Yersinia pestis isolates from all known plague foci of north-east Brazil were analysed by SDS-PAGE. Approximately 20 bands were consistently found in all strains analysed and 11 were selected for comparative studies. Although qualitative differences among the electrophoretic profiles of outer membrane proteins of wild Y. pestis isolates were not observed, quantitative alterations were clearly noted for most of these proteins. No particular quantitative alteration of the electrophoretic profile of outer membrane proteins could be associated with the period of isolation and geographic origin of the isolates. The 64 kDa outer membrane protein was significantly expressed in higher amounts among Y. pestis strains isolated from a recent plague outbreak. The possible use of electrophoretic profiles of outer membrane proteins of wild Y. pestis isolates as a tool for epidemiological studies and for the analysis of virulence determinants is discussed. Images Fig. 2 PMID:2606164

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.

Role of the Yersinia pestis yersiniabactin iron acquisition system in the incidence of flea-borne plague.

PubMed

Sebbane, Florent; Jarrett, Clayton; Gardner, Donald; Long, Daniel; Hinnebusch, B Joseph

2010-12-17

Plague is a flea-borne zoonosis caused by the bacterium Yersinia pestis. Y. pestis mutants lacking the yersiniabactin (Ybt) siderophore-based iron transport system are avirulent when inoculated intradermally but fully virulent when inoculated intravenously in mice. Presumably, Ybt is required to provide sufficient iron at the peripheral injection site, suggesting that Ybt would be an essential virulence factor for flea-borne plague. Here, using a flea-to-mouse transmission model, we show that a Y. pestis strain lacking the Ybt system causes fatal plague at low incidence when transmitted by fleas. Bacteriology and histology analyses revealed that a Ybt-negative strain caused only primary septicemic plague and atypical bubonic plague instead of the typical bubonic form of disease. The results provide new evidence that primary septicemic plague is a distinct clinical entity and suggest that unusual forms of plague may be caused by atypical Y. pestis strains.

The effects of modeled microgravity on growth kinetics, antibiotic susceptibility, cold growth, and the virulence potential of a Yersinia pestis ymoA-deficient mutant and its isogenic parental strain.

PubMed

Lawal, Abidat; Kirtley, Michelle L; van Lier, Christina J; Erova, Tatiana E; Kozlova, Elena V; Sha, Jian; Chopra, Ashok K; Rosenzweig, Jason A

2013-09-01

Previously, we reported that there was no enhancement in the virulence potential (as measured by cell culture infections) of the bacterial pathogen Yersinia pestis (YP) following modeled microgravity/clinorotation growth. We have now further characterized the effects of clinorotation (CR) on YP growth kinetics, antibiotic sensitivity, cold growth, and YP's virulence potential in a murine model of infection. Surprisingly, none of the aforementioned phenotypes were altered. To better understand why CR did not enhance YP's virulence potential as it did for other bacterial pathogens, a YP ΔymoA isogenic mutant in the KIM/D27 background strain that is unable to produce the histone-like YmoA protein and influences DNA topography was used in both cell culture and murine models of infection. YmoA represses type three secretion system (T3SS) virulence gene expression in the yersiniae. Similar to our CR-grown parental YP strain data, the CR-grown ΔymoA mutant induced reduced HeLa cell cytotoxicity with concomitantly decreased Yersinia outer protein E (YopE) and low calcium response V (LcrV) antigen production and secretion. Important, however, were our findings that, although no significant differences were observed in survival of mice infected intraperitoneally with either normal gravity (NG)- or CR-grown parental YP, the ΔymoA mutant induced significantly more mortality in infected mice than did the parental strain following CR growth. Taken together, our data demonstrate that CR did enhance the virulence potential of the YP ΔymoA mutant in a murine infection model (relative to the CR-grown parental strain), despite inducing less HeLa cell rounding in our cell culture infection assay due to reduced T3SS activity. Therefore, CR, which induces a unique type of bacterial stress, might be enhancing YP's virulence potential in vivo through a T3SS-independent mechanism when the histone-like YmoA protein is absent.

[Influence of glucose and galactose on the morphology and biological properties of Yersinia pseudotuberculosis].

PubMed

Bakholdina, S I; Solov'eva, T F; Shubin, F N; Timchenko, N F

2005-01-01

When cultivated in the presence of glucose, irrespective of temperature and the degree of aeration, Y. pseudotuberculosis cells have the ovoid form, constant size and low hydrophobic properties of their surface. Meanwhile the characteristics of the bacteria grown in the medium, carbohydrate-free or with galactose added, essentially depend on the conditions of medium aeration. Under the conditions of intensive stirring at both temperatures these bacteria acquire the coccoid form, not typical for Yersinia, they have a smaller area (approximately 2 times) and more hydrophobic surface in comparison with the cells grown in the presence of glucose. Under stationary conditions the differences between the cells, cultivated in the presence of galactose and glucose, in form and area disappear, but the differences in the hydrophobic properties of the surface are retained. As revealed in this study, the cells grown in the presence of galactose and under the conditions of intensive medium stirring, in contrast to those grown with glucose, have 1.5-fold greater invasive activity, irrespective of aeration conditions, eightfold greater resistance to ampicillin and twofold greater resistance to streptomycin and erythromycin.

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

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

A High-Coverage Yersinia pestis Genome from a Sixth-Century Justinianic Plague Victim

PubMed Central

Feldman, Michal; Harbeck, Michaela; Keller, Marcel; Spyrou, Maria A.; Rott, Andreas; Trautmann, Bernd; Scholz, Holger C.; Päffgen, Bernd; Peters, Joris; McCormick, Michael; Bos, Kirsten; Herbig, Alexander; Krause, Johannes

2016-01-01

The Justinianic Plague, which started in the sixth century and lasted to the mid eighth century, is thought to be the first of three historically documented plague pandemics causing massive casualties. Historical accounts and molecular data suggest the bacterium Yersinia pestis as its etiological agent. Here we present a new high-coverage (17.9-fold) Y. pestis genome obtained from a sixth-century skeleton recovered from a southern German burial site close to Munich. The reconstructed genome enabled the detection of 30 unique substitutions as well as structural differences that have not been previously described. We report indels affecting a lacl family transcription regulator gene as well as nonsynonymous substitutions in the nrdE, fadJ, and pcp genes, that have been suggested as plague virulence determinants or have been shown to be upregulated in different models of plague infection. In addition, we identify 19 false positive substitutions in a previously published lower-coverage Y. pestis genome from another archaeological site of the same time period and geographical region that is otherwise genetically identical to the high-coverage genome sequence reported here, suggesting low-genetic diversity of the plague during the sixth century in rural southern Germany. PMID:27578768

An Experimentally-Supported Genome-Scale Metabolic Network Reconstruction for Yersinia pestis CO92

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

Charusanti, Pep; Chauhan, Sadhana; Mcateer, Kathleen

2011-10-13

Yersinia pestis is a gram-negative bacterium that causes plague, a disease linked historically to the Black Death in Europe during the Middle Ages and to several outbreaks during the modern era. Metabolism in Y. pestis displays remarkable flexibility and robustness, allowing the bacterium to proliferate in both warm-blooded mammalian hosts and cold-blooded insect vectors such as fleas. Here we report a genome-scale reconstruction and mathematical model of metabolism for Y. pestis CO92 and supporting experimental growth and metabolite measurements. The model contains 815 genes, 678 proteins, 963 unique metabolites and 1678 reactions, accurately simulates growth on a range of carbonmore » sources both qualitatively and quantitatively, and identifies gaps in several key biosynthetic pathways and suggests how those gaps might be filled. Furthermore, our model presents hypotheses to explain certain known nutritional requirements characteristic of this strain. Y. pestis continues to be a dangerous threat to human health during modern times. The Y. pestis genome-scale metabolic reconstruction presented here, which has been benchmarked against experimental data and correctly reproduces known phenotypes, thus provides an in silico platform with which to investigate the metabolism of this important human pathogen.« less

The Yersinia pestis gcvB gene encodes two small regulatory RNA molecules

PubMed Central

McArthur, Sarah D; Pulvermacher, Sarah C; Stauffer, George V

2006-01-01

Background In recent years it has become clear that small non-coding RNAs function as regulatory elements in bacterial virulence and bacterial stress responses. We tested for the presence of the small non-coding GcvB RNAs in Y. pestis as possible regulators of gene expression in this organism. Results In this study, we report that the Yersinia pestis KIM6 gcvB gene encodes two small RNAs. Transcription of gcvB is activated by the GcvA protein and repressed by the GcvR protein. The gcvB-encoded RNAs are required for repression of the Y. pestis dppA gene, encoding the periplasmic-binding protein component of the dipeptide transport system, showing that the GcvB RNAs have regulatory activity. A deletion of the gcvB gene from the Y. pestis KIM6 chromosome results in a decrease in the generation time of the organism as well as a change in colony morphology. Conclusion The results of this study indicate that the Y. pestis gcvB gene encodes two small non-coding regulatory RNAs that repress dppA expression. A gcvB deletion is pleiotropic, suggesting that the sRNAs are likely involved in controlling genes in addition to dppA. PMID:16768793

Evaluation of Psn, HmuR and a modified LcrV protein delivered to mice by live attenuated Salmonella as a vaccine against bubonic and pneumonic Yersinia pestis challenge.

PubMed

Branger, Christine G; Sun, Wei; Torres-Escobar, Ascención; Perry, Robert; Roland, Kenneth L; Fetherston, Jacqueline; Curtiss, Roy

2010-12-16

We evaluated the ability of Yersinia pestis antigens HmuR, Psn and modified forms of LcrV delivered by live attenuated Salmonella strains to stimulate a protective immune response against subcutaneous or intranasal challenge with Y. pestis CO92. LcrV196 is a previously described truncated protein that includes aa 131-326 of LcrV and LcrV5214 has been modified to replace five key amino acids required for interaction with the TLR2 receptor. Psn is the outer membrane receptor for the siderophore, yersiniabactin, and the bacteriocin, pesticin. Mice immunized with Salmonella synthesizing Psn, LcrV196 or LcrV5214 developed serum IgG responses to the respective Yersinia antigen and were protected against pneumonic challenge with Y. pestis. Immunization with Salmonella synthesizing Psn or LcrV196 was sufficient to afford nearly full protection against bubonic challenge, while immunization with the strain synthesizing LcrV5214 was not protective. Immunization with Salmonella synthesizing HmuR, an outer membrane protein involved in heme acquisition in Y. pestis, was poorly immunogenic and did not elicit a protective response against either challenge route. These findings indicate that both Psn and LcrV196 delivered by Salmonella provide protection against both bubonic and pneumonic plague. Copyright © 2010 Elsevier Ltd. All rights reserved.

BIRC7 gene in channel catfish (Ictalurus punctatus): identification and expression analysis in response to Edwardsiella tarda, Streptococcus iniae and Channel catfish Hemorrhage Reovirus.

PubMed

Li, Min; Liu, Yang; Wang, Qi-Long; Chen, Song-Lin; Sha, Zhen-Xia

2012-07-01

A family member of inhibitor of apoptosis protein (IAP) termed baculoviral IAP repeat-containing 7 (BIRC7) from channel catfish (Ictalurus punctatus) was identified, the full length cDNA sequence of channel catfish BIRC7 (CcBIRC7) was 1686 bp, containing a 5'UTR of 93 bp, a 3'UTR of 399 bp with a poly (A) tail and an ORF of 1194 bp encoding a putative protein of 398 amino acids. The putative CcBIRC7 protein contains two BIR super-family conservative domains and a C-terminal RING finger motif. Phylogenetic analysis showed that catfish CcBIRC7 was moderately conserved with other BIRC7. Quantitative real-time PCR was conducted to examine the expression profiles of CcBIRC7 in healthy tissues and responding to different pathogens (Edwardsiella tarda, Streptococcus iniae and Channel catfish Hemorrhage Reovirus (CCRV)). CcBIRC7 was widely expressed in healthy tissues of channel catfish and with the highest 37.28-fold expression in blood. E. tarda and S. iniae could induce CcBIRC7 gene expression drastically in head kidney, liver and spleen, which the peak value reached 31.6-fold, 613.9-fold and 34.4-fold increase by E. tarda infection, and 248.3-fold, 1540.3-fold and 120.4-fold increase post S. iniae challenge, respectively. While, CCRV virus could slightly induce CcBIRC7 expression in head kidney and liver but reduce it in spleen. The result suggested BIRC7 may play a potential role in channel catfish innate immune system against bacterial and virus infections, especially as the anti-bacteria immune gene. This is the first report of BIRC7 gene identification and its expression in fish. Copyright © 2012 Elsevier Ltd. All rights reserved.

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

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.

The Csr/Rsm system of Yersinia and related pathogens: a post-transcriptional strategy for managing virulence.

PubMed

Heroven, Ann Kathrin; Böhme, Katja; Dersch, Petra

2012-04-01

This review emphasizes the function and regulation of the Csr regulatory system in the human enteropathogen Yersinia pseudotuberculosis and compares its features with the homologous Csr/Rsm systems of related pathogens. The Csr/Rsm systems of eubacteria form a complex regulatory network in which redundant non-translated Csr/Rsm-RNAs bind the RNA-binding protein CsrA/RsmA, thereby preventing its interaction with mRNA targets. The Csr system is controlled by the BarA/UvrY-type of two-component sensor-regulator systems. Apart from that, common or pathogen-specific regulators control the abundance of the Csr components. The coordinate control of virulence factors and infection-linked physiological traits by the Csr/Rsm systems helps the pathogens to adapt individually to rapidly changing conditions to which they are exposed during the different stages of an infection. As Csr/Rsm function is relevant for full virulence, it represents a target suitable for antimicrobial drug development.

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

Experimental infection of domestic ferrets (Mustela putorius furo) and Siberian polecats (Mustela eversmanni) with Yersinia pestis.

PubMed

Williams, E S; Thorne, E T; Quan, T J; Anderson, S L

1991-07-01

Eight domestic ferrets (Mustela putorius furo) and two Siberian polecats (M. eversmanni) were inoculated subcutaneously with 12 to 1.2 x 10(7) Yersinia pestis originally isolated during an epizootic of plague in white-tailed prairie dogs (Cynomys leucurus) near Meeteetse, Park County, Wyoming (USA) in 1985. None of the ferrets or polecats developed clinical signs of disease which suggested that black-footed ferrets (M. nigripes), a congener, also would be resistant to plague. All animals receiving greater than or equal to 1.2 X 10(3) organisms produced serum antibodies detected by the passive hemagglutination test with titers peaking at 1:1,024 and remaining positive until at least 219 days postinoculation. Sera collected from 12 free-ranging black-footed ferrets near Meeteetse in 1984 and 1985 were negative for antibodies against Y. pestis. Prevalence of antibodies against Y. pestis was high in other carnivores collected from the same area in 1986.

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.

Recombinant V antigen protects mice against pneumonic and bubonic plague caused by F1-capsule-positive and -negative strains of Yersinia pestis.

PubMed

Anderson, G W; Leary, S E; Williamson, E D; Titball, R W; Welkos, S L; Worsham, P L; Friedlander, A M

1996-11-01

The purified recombinant V antigen from Yersinia pestis, expressed in Escherichia coli and adsorbed to aluminum hydroxide, an adjuvant approved for human use, was used to immunize outbred Hsd:ND4 mice subcutaneously. Immunization protected mice from lethal bubonic and pneumonic plague caused by CO92, a wild-type F1+ strain, or by the isogenic F1- strain C12. This work demonstrates that a subunit plague vaccine formulated for human use provides significant protection against bubonic plague caused by an F1- strain (C12) or against substantial aerosol challenges from either F1+ (CO92) or F1-(C12) Y. pestis.

Evaluation of the FilmArray® system for detection of Bacillus anthracis, Francisella tularensis, and Yersinia pestis

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

Seiner, Derrick R.; Colburn, Heather A.; Baird, Cheryl L.

2013-04-29

To evaluate the sensitivity and specificity of the Idaho Technologies FilmArray® Biothreat Panel for the detection of Bacillus anthracis (Ba), Francisella tularensis (Ft), and Yersinia pestis (Yp) DNA, and demonstrate the detection of Ba spores. Methods and Results: DNA samples from Ba, Ft and Yp strains and near-neighbors, and live Ba spores were analyzed using the Biothreat Panel, a multiplexed PCR-based assay for 17 pathogens and toxins. Sensitivity studies with DNA suggest a limit of detection of 250 genome equivalents (GEs) per sample. Furthermore, the correct call of Ft, Yp or Bacillus species was made in 63 of 72 samplesmore » tested at 25 GE or less. With samples containing 25 Ba Sterne spores, at least one of the two possible Ba markers were identified in all samples tested. We observed no cross-reactivity with near-neighbor DNAs.« less

Seroprevalence and spatial distribution dynamics of Yersinia pestis antibodies in dogs and cats from plague foci in the State of Ceará, Northeastern Brazil.

PubMed

Sousa, Larissa Leão Ferrer de; Alencar, Carlos Henrique Morais de; Almeida, Alzira Maria Paiva de; Cavalcanti, Luciano Pamplona de Góes

2017-01-01

In Brazil, the plague is established in several foci located mainly in the northeastern part of the country, where it alternates between active and quiescent periods. These foci in the State of Ceará have high epidemiological importance. In addition to other plague detection activities, plague areas can be monitored through serological surveys of dogs and cats (domestic carnivores), which, following feeding on plague-infected rodents, can develop mild to severe forms of the disease and produce long-lasting antibodies. This study aimed to characterize the circulation dynamics and spatial distribution of Yersinia pestis antibodies in dogs and cats in plague foci areas of Ceará. An ecological study was conducted to analyze the temporal series and spatial distribution of secondary data obtained from domestic carnivore serum surveillance in Ceará's plague areas from 1990 to 2014. Joinpoint analysis revealed that the overall trend was a reduction in antibody-positive animals. The mean proportion of antibody-positivity during the whole study period was 1.5% (3,023/203,311) for dogs, and 0.7% (426/61,135) for cats, with more than 4% antibody-positivity in dogs in 1997 and 2002. Antibody titers ranging from 1/16 to 1/64 were frequent. Despite fluctuations and a significant reduction, in recent years, there were antibody-positive animals annually throughout the study period, and the localities containing antibody-positive animals increased in number. Yersinia pestis is actively circulating in the study areas, posing a danger to the human population.

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

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.

Structure of the cytoplasmic domain of Yersinia pestis YscD, an essential component of the type III secretion system

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

Lountos, George T.; Tropea, Joseph E.; Waugh, David S.

2012-09-17

The Yersinia pestis YscD protein is an essential component of the type III secretion system. YscD consists of an N-terminal cytoplasmic domain (residues 1-121), a transmembrane linker (122-142) and a large periplasmic domain (143-419). Both the cytoplasmic and the periplasmic domains are required for the assembly of the type III secretion system. Here, the structure of the YscD cytoplasmic domain solved by SAD phasing is presented. Although the three-dimensional structure is similar to those of forkhead-associated (FHA) domains, comparison with the structures of canonical FHA domains revealed that the cytoplasmic domain of YscD lacks the conserved residues that are requiredmore » for binding phosphothreonine and is therefore unlikely to function as a true FHA domain.« less

Detection and prevalence of pathogenic Yersinia enterocolitica in refrigerated and frozen dairy products by duplex PCR and dot hybridization targeting the virF and ail genes.

PubMed

Ye, Y W; Ling, N; Han, Y J; Wu, Q P

2014-11-01

Pathogenic Yersinia enterocolitica is involved in yersiniosis through expression of chromosome-borne or plasmid-borne virulence factors. Yersinia enterocolitica is a cold-tolerant pathogen frequently isolated from refrigerated or frozen foods. However, little attention has been focused on the prevalence of pathogenic Y. enterocolitica in refrigerated or frozen dairy samples in China. In this study, we developed a new duplex PCR targeting the plasmid-borne virF gene and chromosome-borne ail gene for detection of pathogenic Y. enterocolitica isolates. We established a detection limit for the duplex PCR of 6.5 × 10(2)cfu/mL in artificially contaminated dairy samples. In addition, the duplex PCR could detect directly 4.5 to 5.7 cfu of Y. enterocolitica in 5 mL of brain heart infusion broth after 6 h of enrichment at 28 °C. A newly developed dot hybridization assay further confirmed specificity of the duplex PCR for detection of virulent Y. enterocolitica. Furthermore, 13 Y. enterocolitica and 5 pathogenic strains, from 88 commercial frozen or refrigerated dairy products, were detected successfully by the China National Standard method (GB/T4789.8-2008) and the duplex PCR, respectively. Finally, biotypes and serotypes of pathogenic Y. enterocolitica strains were further characterized. The duplex PCR developed here is reliable for large-scale screening, routine monitoring, and risk assessment of pathogenic Y. enterocolitica in refrigerated or frozen dairy products. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Beyond Chloride Brines: Variable Metabolomic Responses in the Anaerobic Organism Yersinia intermedia MASE-LG-1 to NaCl and MgSO4 at Identical Water Activity

PubMed Central

Schwendner, Petra; Bohmeier, Maria; Rettberg, Petra; Beblo-Vranesevic, Kristina; Gaboyer, Frédéric; Moissl-Eichinger, Christine; Perras, Alexandra K.; Vannier, Pauline; Marteinsson, Viggó T.; Garcia-Descalzo, Laura; Gómez, Felipe; Malki, Moustafa; Amils, Ricardo; Westall, Frances; Riedo, Andreas; Monaghan, Euan P.; Ehrenfreund, Pascale; Cabezas, Patricia; Walter, Nicolas; Cockell, Charles

2018-01-01

Growth in sodium chloride (NaCl) is known to induce stress in non-halophilic microorganisms leading to effects on the microbial metabolism and cell structure. Microorganisms have evolved a number of adaptations, both structural and metabolic, to counteract osmotic stress. These strategies are well-understood for organisms in NaCl-rich brines such as the accumulation of certain organic solutes (known as either compatible solutes or osmolytes). Less well studied are responses to ionic environments such as sulfate-rich brines which are prevalent on Earth but can also be found on Mars. In this paper, we investigated the global metabolic response of the anaerobic bacterium Yersinia intermedia MASE-LG-1 to osmotic salt stress induced by either magnesium sulfate (MgSO4) or NaCl at the same water activity (0.975). Using a non-targeted mass spectrometry approach, the intensity of hundreds of metabolites was measured. The compatible solutes L-asparagine and sucrose were found to be increased in both MgSO4 and NaCl compared to the control sample, suggesting a similar osmotic response to different ionic environments. We were able to demonstrate that Yersinia intermedia MASE-LG-1 accumulated a range of other compatible solutes. However, we also found the global metabolic responses, especially with regard to amino acid metabolism and carbohydrate metabolism, to be salt-specific, thus, suggesting ion-specific regulation of specific metabolic pathways. PMID:29535699

Oral vaccination against bubonic plague using a live avirulent Yersinia pseudotuberculosis strain.

PubMed

Blisnick, Thierry; Ave, Patrick; Huerre, Michel; Carniel, Elisabeth; Demeure, Christian E

2008-08-01

We evaluated the possibility of using Yersinia pseudotuberculosis as a live vaccine against plague because it shares high genetic identity with Y. pestis while being much less virulent, genetically much more stable, and deliverable orally. A total of 41 Y. pseudotuberculosis strains were screened by PCR for the absence of the high pathogenicity island, the superantigens YPM, and the type IV pilus and the presence of the pYV virulence plasmid. One strain (IP32680) fulfilled these criteria. This strain was avirulent in mice upon intragastric or subcutaneous inoculation and persisted for 2 months in the mouse intestine without clinical signs of disease. IP32680 reached the mesenteric lymph nodes, spleen, and liver without causing major histological lesions and was cleared after 13 days. The antibodies produced in vaccinated animals recognized both Y. pseudotuberculosis and Y. pestis antigens efficiently. After a subcutaneous challenge with Y. pestis CO92, bacteria were found in low amounts in the organs and rarely in the blood of vaccinated animals. One oral IP32680 inoculation protected 75% of the mice, and two inoculations induced much higher antibody titers and protected 88% of the mice. Our results thus validate the concept that an attenuated Y. pseudotuberculosis strain can be an efficient, inexpensive, safe, and easy-to-produce live vaccine for oral immunization against bubonic plague.

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

Hierarchy of Iron Uptake Systems: Yfu and Yiu Are Functional in Yersinia pestis▿

PubMed Central

Kirillina, Olga; Bobrov, Alexander G.; Fetherston, Jacqueline D.; Perry, Robert D.

2006-01-01

In addition to the yersiniabactin (Ybt) siderophore-dependent system, two inorganic iron ABC transport systems of Yersinia pestis, Yfe and Yfu, have been characterized. Here we show that the Yfu system functions in Y. pestis: a Ybt− Yfe− Yfu− mutant exhibited a greater growth defect under iron-deficient conditions than its Ybt− Yfe− parental strain. We also demonstrate that another putative Y. pestis iron uptake system, Yiu, which potentially encodes an outer membrane receptor, YiuR, and an ABC iron transport cassette, YiuABC, is functional. The cloned yiuABC operon restored growth of an enterobactin-deficient mutant Escherichia coli strain, 1017, under iron-chelated conditions. Iron uptake by the Yiu system in Y. pestis was demonstrated only when the Ybt, Yfe, and Yfu systems were mutated. Using a yiuA::lacZ fusion, we show that the yiuABC promoter is repressed by iron through Fur. A mouse model of bubonic plague failed to show a significant role for the Yiu system in the disease process. These results demonstrate that two additional iron transporters are functional in Y. pestis and indicate that there is a hierarchy of iron transporters, with Ybt being most effective and Yiu being the least effective of those systems which have been characterized. PMID:16954402

Recent Findings Regarding Maintenance of Enzootic Variants of Yersinia pestis in Sylvatic Reservoirs and Their Significance in the Evolution of Epidemic Plague

PubMed Central

Brubaker, Robert R.

2010-01-01

Abstract Despite the widespread presence of bubonic plague in sylvatic reservoirs throughout the world, the causative agent (Yersinia pestis) evolved in its present form within the last 20,000 years from enteropathogenic Yersinia pseudotuberculosis. Comparison of the genomes from the two species revealed that Y. pestis possesses only a few unique plasmid-encoded genes that contribute to acute disease, whereas this organism has lost about 13% of the chromosomal genes that remain active in Y. pseudotuberculosis. These losses reflect readily detectable additions, deletions, transpositions, inversions, and acquisition of about 70 insertion sequence (IS) inserts, none of which are likely to promote increased virulence. In contrast, major enzymes of intermediary metabolism, including glucose 6-phosphate dehydrogenase (Zwf ) and aspartase, are present but not catalytically functional due to the presence of missense mutations. The latter are generally not detectable by the technology of bioinformatics and, in the case of Y. pestis, result in radical changes in the metabolic flow of carbon. As an important consequence, plague bacilli exhibit a stringent low-calcium response characterized by conversion of L-glutamate (and metabolically related amino acids) to L-aspartate with secretion of the latter into supernatant fluid at 37°C in culture media containing Na+ but lacking added Ca2+. This phenomenon also occurs in vivo and likely adversely affects the bioenergetics of host amino acid pools. Curiously, aspartase is functional in all tested enzootic (pestoides) strains of Y. pestis. These isolates are typically restricted to the ancient plague reservoirs of Central Asia and Africa and are fully virulent in members of the rodent Superfamily Muroidea but avirulent in guinea pigs and man. The implications of these findings for the distribution and ecology of Y. pestis could be significant. PMID:20158336

Recent findings regarding maintenance of enzootic variants of Yersinia pestis in sylvatic reservoirs and their significance in the evolution of epidemic plague.

PubMed

Bearden, Scott W; Brubaker, Robert R

2010-01-01

Despite the widespread presence of bubonic plague in sylvatic reservoirs throughout the world, the causative agent (Yersinia pestis) evolved in its present form within the last 20,000 years from enteropathogenic Yersinia pseudotuberculosis. Comparison of the genomes from the two species revealed that Y. pestis possesses only a few unique plasmid-encoded genes that contribute to acute disease, whereas this organism has lost about 13% of the chromosomal genes that remain active in Y. pseudotuberculosis. These losses reflect readily detectable additions, deletions, transpositions, inversions, and acquisition of about 70 insertion sequence (IS) inserts, none of which are likely to promote increased virulence. In contrast, major enzymes of intermediary metabolism, including glucose 6-phosphate dehydrogenase (Zwf ) and aspartase, are present but not catalytically functional due to the presence of missense mutations. The latter are generally not detectable by the technology of bioinformatics and, in the case of Y. pestis, result in radical changes in the metabolic flow of carbon. As an important consequence, plague bacilli exhibit a stringent low-calcium response characterized by conversion of L-glutamate (and metabolically related amino acids) to L-aspartate with secretion of the latter into supernatant fluid at 37 degrees C in culture media containing Na(+) but lacking added Ca(2+). This phenomenon also occurs in vivo and likely adversely affects the bioenergetics of host amino acid pools. Curiously, aspartase is functional in all tested enzootic (pestoides) strains of Y. pestis. These isolates are typically restricted to the ancient plague reservoirs of Central Asia and Africa and are fully virulent in members of the rodent Superfamily Muroidea but avirulent in guinea pigs and man. The implications of these findings for the distribution and ecology of Y. pestis could be significant.

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.

Regulation of the Yersinia type III secretion system: traffic control

PubMed Central

Dewoody, Rebecca S.; Merritt, Peter M.; Marketon, Melanie M.

2013-01-01

Yersinia species, as well as many other Gram-negative pathogens, use a type III secretion system (T3SS) to translocate effector proteins from the bacterial cytoplasm to the host cytosol. This T3SS resembles a molecular syringe, with a needle-like shaft connected to a basal body structure, which spans the inner and outer bacterial membranes. The basal body of the injectisome shares a high degree of homology with the bacterial flagellum. Extending from the T3SS basal body is the needle, which is a polymer of a single protein, YscF. The distal end of the needle serves as a platform for the assembly of a tip complex composed of LcrV. Though never directly observed, prevailing models assume that LcrV assists in the insertion of the pore-forming proteins YopB and YopD into the host cell membrane. This completes a bridge between the bacterium and host cell to provide a continuous channel through which effectors are delivered. Significant effort has gone into understanding how the T3SS is assembled, how its substrates are recognized and how substrate delivery is controlled. Arguably the latter topic is the least understood; however, recent advances have provided new insight, and therefore, this review will focus primarily on summarizing the current state of knowledge regarding the control of substrate delivery by the T3SS. Specifically, we will discuss the roles of YopK, as well as YopN and YopE, which have long been linked to regulation of translocation. We also propose models whereby the YopK regulator communicates with the basal body of the T3SS to control translocation. PMID:23390616

A Noise Trimming and Positional Significance of Transposon Insertion System to Identify Essential Genes in Yersinia pestis

NASA Astrophysics Data System (ADS)

Yang, Zheng Rong; Bullifent, Helen L.; Moore, Karen; Paszkiewicz, Konrad; Saint, Richard J.; Southern, Stephanie J.; Champion, Olivia L.; Senior, Nicola J.; Sarkar-Tyson, Mitali; Oyston, Petra C. F.; Atkins, Timothy P.; Titball, Richard W.

2017-02-01

Massively parallel sequencing technology coupled with saturation mutagenesis has provided new and global insights into gene functions and roles. At a simplistic level, the frequency of mutations within genes can indicate the degree of essentiality. However, this approach neglects to take account of the positional significance of mutations - the function of a gene is less likely to be disrupted by a mutation close to the distal ends. Therefore, a systematic bioinformatics approach to improve the reliability of essential gene identification is desirable. We report here a parametric model which introduces a novel mutation feature together with a noise trimming approach to predict the biological significance of Tn5 mutations. We show improved performance of essential gene prediction in the bacterium Yersinia pestis, the causative agent of plague. This method would have broad applicability to other organisms and to the identification of genes which are essential for competitiveness or survival under a broad range of stresses.

A Noise Trimming and Positional Significance of Transposon Insertion System to Identify Essential Genes in Yersinia pestis

PubMed Central

Yang, Zheng Rong; Bullifent, Helen L.; Moore, Karen; Paszkiewicz, Konrad; Saint, Richard J.; Southern, Stephanie J.; Champion, Olivia L.; Senior, Nicola J.; Sarkar-Tyson, Mitali; Oyston, Petra C. F.; Atkins, Timothy P.; Titball, Richard W.

2017-01-01

Massively parallel sequencing technology coupled with saturation mutagenesis has provided new and global insights into gene functions and roles. At a simplistic level, the frequency of mutations within genes can indicate the degree of essentiality. However, this approach neglects to take account of the positional significance of mutations - the function of a gene is less likely to be disrupted by a mutation close to the distal ends. Therefore, a systematic bioinformatics approach to improve the reliability of essential gene identification is desirable. We report here a parametric model which introduces a novel mutation feature together with a noise trimming approach to predict the biological significance of Tn5 mutations. We show improved performance of essential gene prediction in the bacterium Yersinia pestis, the causative agent of plague. This method would have broad applicability to other organisms and to the identification of genes which are essential for competitiveness or survival under a broad range of stresses. PMID:28165493

Isothiazolidinone (IZD) as a phosphoryl mimetic in inhibitors of the Yersinia pestis protein tyrosine phosphatase YopH

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

Kim, Sung-Eun; Bahta, Medhanit; Lountos, George T.

2011-07-01

The first X-ray crystal structure of the Y. pestis protein tyrosine phosphatase YopH in complex with an isothiazolidinone-based lead-fragment compound is reported. Isothiazolidinone (IZD) heterocycles can act as effective components of protein tyrosine phosphatase (PTP) inhibitors by simultaneously replicating the binding interactions of both a phosphoryl group and a highly conserved water molecule, as exemplified by the structures of several PTP1B–inhibitor complexes. In the first unambiguous demonstration of IZD interactions with a PTP other than PTP1B, it is shown by X-ray crystallography that the IZD motif binds within the catalytic site of the Yersinia pestis PTP YopH by similarly displacingmore » a highly conserved water molecule. It is also shown that IZD-based bidentate ligands can inhibit YopH in a nonpromiscuous fashion at low micromolar concentrations. Hence, the IZD moiety may represent a useful starting point for the development of YopH inhibitors.« less

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

The subcutaneous inoculation of pH 6 antigen mutants of Yersinia pestis does not affect virulence and immune response in mice.

PubMed

Anisimov, Andrey P; Bakhteeva, Irina V; Panfertsev, Evgeniy A; Svetoch, Tat'yana E; Kravchenko, Tat'yana B; Platonov, Mikhail E; Titareva, Galina M; Kombarova, Tat'yana I; Ivanov, Sergey A; Rakin, Alexander V; Amoako, Kingsley K; Dentovskaya, Svetlana V

2009-01-01

Two isogenic sets of Yersinia pestis strains were generated, composed of wild-type strains 231 and I-1996, their non-polar pH 6(-) mutants with deletions in the psaA gene that codes for its structural subunit or the whole operon, as well as strains with restored ability for temperature- and pH-dependent synthesis of adhesion pili or constitutive production of pH 6 antigen. The mutants were generated by site-directed mutagenesis of the psa operon and subsequent complementation in trans. It was shown that the loss of synthesis or constitutive production of pH 6 antigen did not influence Y. pestis virulence or the average survival time of subcutaneously inoculated BALB/c naïve mice or animals immunized with this antigen.

YERSINIA PSEUDOTUBERCULOSIS, SEROGROUP O:1A, INFECTION IN TWO AMAZON PARROTS (AMAZONA AESTIVA AND AMAZONA ORATRIX) WITH HEPATIC HEMOSIDEROSIS.

PubMed

Galosi, Livio; Farneti, Silvana; Rossi, Giacomo; Cork, Susan Catherine; Ferraro, Stefano; Magi, Gian Enrico; Petrini, Stefano; Valiani, Andrea; Cuteri, Vincenzo; Attili, Anna-Rita

2015-09-01

Necropsies were conducted on a female blue-fronted Amazon (Amazona aestiva) and a female yellow-headed Amazon (Amazona oratrix) that died after depression, ruffled feathers, diarrhea, and biliverdin in the urine. Gross and microscopic examinations revealed multifocal necrosis in the liver, spleen, lungs, kidneys, intestines, and heart caused by acute bacteremia. Yersinia pseudotuberculosis, serogroup O:1a, was isolated by culturing from the visceral lesions in the liver, intestines, and spleen. Virulence gene analysis showed the presence of the inv gene and the complete pathogenicity island: IS100, psn, yptE, irp1, irp2 ybtP-ybtQ, ybtX-ybtS, and int asnT-Int. Histopathologic findings and chemical analysis also demonstrated hepatic hemosiderosis. As has been demonstrated in other species, hemosiderosis may predispose Amazona spp. to systemic infection with Y. pseudotuberculosis after enteric disease.

A Yersinia pestis lpxM-mutant live vaccine induces enhanced immunity against bubonic plague in mice and guinea pigs.

PubMed

Feodorova, V A; Pan'kina, L N; Savostina, E P; Sayapina, L V; Motin, V L; Dentovskaya, S V; Shaikhutdinova, R Z; Ivanov, S A; Lindner, B; Kondakova, A N; Bystrova, O V; Kocharova, N A; Senchenkova, S N; Holst, O; Pier, G B; Knirel, Y A; Anisimov, A P

2007-11-01

The lpxM mutant of the live vaccine Yersinia pestis EV NIIEG strain synthesising a less toxic penta-acylated lipopolysaccharide was found to be avirulent in mice and guinea pigs, notably showing no measurable virulence in Balb/c mice which do retain some susceptibility to the parental strain itself. Twenty-one days after a single injection of the lpxM-mutant, 85-100% protection was achieved in outbred mice and guinea pigs, whereas a 43% protection rate was achieved in Balb/c mice given single low doses (10(3) to 2.5 x 10(4) CFU) of this vaccine. A subcutaneous challenge with 2000 median lethal doses (equal to 20,000 CFU) of fully virulent Y. pestis 231 strain, is a 6-10-fold higher dose than that which the EV NIIEG itself can protect against.

Inactivation of Peroxiredoxin 6 by the Pla Protease of Yersinia pestis

PubMed Central

Zimbler, Daniel L.; Eddy, Justin L.; Schroeder, Jay A.

2015-01-01

Pneumonic plague represents the most severe form of disease caused by Yersinia pestis due to its ease of transmission, rapid progression, and high mortality rate. The Y. pestis outer membrane Pla protease is essential for the development of pneumonic plague; however, the complete repertoire of substrates cleaved by Pla in the lungs is not known. In this study, we describe a proteomic screen to identify host proteins contained within the bronchoalveolar lavage fluid of mice that are cleaved and/or processed by Y. pestis in a Pla-dependent manner. We identified peroxiredoxin 6 (Prdx6), a host factor that contributes to pulmonary surfactant metabolism and lung defense against oxidative stress, as a previously unknown substrate of Pla. Pla cleaves Prdx6 at three distinct sites, and these cleavages disrupt both the peroxidase and phospholipase A2 activities of Prdx6. In addition, we found that infection with wild-type Y. pestis reduces the abundance of extracellular Prdx6 in the lungs compared to that after infection with Δpla Y. pestis, suggesting that Pla cleaves Prdx6 in the pulmonary compartment. However, following infection with either wild-type or Δpla Y. pestis, Prdx6-deficient mice exhibit no differences in bacterial burden, host immune response, or lung damage from wild-type mice. Thus, while Pla is able to disrupt Prdx6 function in vitro and reduce Prdx6 levels in vivo, the cleavage of Prdx6 has little detectable impact on the progression or outcome of pneumonic plague. PMID:26553463

Inactivation of Peroxiredoxin 6 by the Pla Protease of Yersinia pestis.

PubMed

Zimbler, Daniel L; Eddy, Justin L; Schroeder, Jay A; Lathem, Wyndham W

2016-01-01

Pneumonic plague represents the most severe form of disease caused by Yersinia pestis due to its ease of transmission, rapid progression, and high mortality rate. The Y. pestis outer membrane Pla protease is essential for the development of pneumonic plague; however, the complete repertoire of substrates cleaved by Pla in the lungs is not known. In this study, we describe a proteomic screen to identify host proteins contained within the bronchoalveolar lavage fluid of mice that are cleaved and/or processed by Y. pestis in a Pla-dependent manner. We identified peroxiredoxin 6 (Prdx6), a host factor that contributes to pulmonary surfactant metabolism and lung defense against oxidative stress, as a previously unknown substrate of Pla. Pla cleaves Prdx6 at three distinct sites, and these cleavages disrupt both the peroxidase and phospholipase A2 activities of Prdx6. In addition, we found that infection with wild-type Y. pestis reduces the abundance of extracellular Prdx6 in the lungs compared to that after infection with Δpla Y. pestis, suggesting that Pla cleaves Prdx6 in the pulmonary compartment. However, following infection with either wild-type or Δpla Y. pestis, Prdx6-deficient mice exhibit no differences in bacterial burden, host immune response, or lung damage from wild-type mice. Thus, while Pla is able to disrupt Prdx6 function in vitro and reduce Prdx6 levels in vivo, the cleavage of Prdx6 has little detectable impact on the progression or outcome of pneumonic plague. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

The Pla Protease of Yersinia pestis Degrades Fas Ligand to Manipulate Host Cell Death and Inflammation

PubMed Central

Caulfield, Adam J.; Walker, Margaret E.; Gielda, Lindsay M.; Lathem, Wyndham W.

2014-01-01

SUMMARY Pneumonic plague is a deadly respiratory disease caused by Yersinia pestis. The bacterial protease Pla contributes to disease progression and manipulation of host immunity, but the mechanisms by which this occurs are largely unknown. Here we show that Pla degrades the apoptotic signaling molecule Fas ligand (FasL) to prevent host cell apoptosis and inflammation. Wild-type Y. pestis, but not a Pla mutant (Δpla), degrades FasL, which results in decreased downstream caspase-3/7 activation and reduced apoptosis. Similarly, lungs of mice challenged with wild-type Y. pestis show reduced levels of FasL and activated caspase-3/7 compared to Δpla infection. Consistent with a role for FasL in regulating immune responses, Δpla infection results in aberrant pro-inflammatory cytokine levels. The loss of FasL or inhibition of caspase activity alters host inflammatory responses and enables enhanced Y. pestis outgrowth in the lungs. Thus, by degrading FasL, Y. pestis manipulates host cell death pathways to facilitate infection. PMID:24721571

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

Glutathionylation of Yersinia pestis LcrV and Its Effects on Plague Pathogenesis

PubMed Central

Mitchell, Anthony; Tam, Christina; Elli, Derek; Charlton, Thomas; Osei-Owusu, Patrick; Fazlollahi, Farbod; Faull, Kym F.

2017-01-01

ABSTRACT Glutathionylation, the formation of reversible mixed disulfides between glutathione and protein cysteine residues, is a posttranslational modification previously observed for intracellular proteins of bacteria. Here we show that Yersinia pestis LcrV, a secreted protein capping the type III secretion machine, is glutathionylated at Cys273 and that this modification promotes association with host ribosomal protein S3 (RPS3), moderates Y. pestis type III effector transport and killing of macrophages, and enhances bubonic plague pathogenesis in mice and rats. Secreted LcrV was purified and analyzed by mass spectrometry to reveal glutathionylation, a modification that is abolished by the codon substitution Cys273Ala in lcrV. Moreover, the lcrVC273A mutation enhanced the survival of animals in models of bubonic plague. Investigating the molecular mechanism responsible for these virulence attributes, we identified macrophage RPS3 as a ligand of LcrV, an association that is perturbed by the Cys273Ala substitution. Furthermore, macrophages infected by the lcrVC273A variant displayed accelerated apoptotic death and diminished proinflammatory cytokine release. Deletion of gshB, which encodes glutathione synthetase of Y. pestis, resulted in undetectable levels of intracellular glutathione, and we used a Y. pestis ΔgshB mutant to characterize the biochemical pathway of LcrV glutathionylation, establishing that LcrV is modified after its transport to the type III needle via disulfide bond formation with extracellular oxidized glutathione. PMID:28512097

A draft genome of Yersinia pestis from victims of the Black Death.

PubMed

Bos, Kirsten I; Schuenemann, Verena J; Golding, G Brian; Burbano, Hernán A; Waglechner, Nicholas; Coombes, Brian K; McPhee, Joseph B; DeWitte, Sharon N; Meyer, Matthias; Schmedes, Sarah; Wood, James; Earn, David J D; Herring, D Ann; Bauer, Peter; Poinar, Hendrik N; Krause, Johannes

2011-10-12

Technological advances in DNA recovery and sequencing have drastically expanded the scope of genetic analyses of ancient specimens to the extent that full genomic investigations are now feasible and are quickly becoming standard. This trend has important implications for infectious disease research because genomic data from ancient microbes may help to elucidate mechanisms of pathogen evolution and adaptation for emerging and re-emerging infections. Here we report a reconstructed ancient genome of Yersinia pestis at 30-fold average coverage from Black Death victims securely dated to episodes of pestilence-associated mortality in London, England, 1348-1350. Genetic architecture and phylogenetic analysis indicate that the ancient organism is ancestral to most extant strains and sits very close to the ancestral node of all Y. pestis commonly associated with human infection. Temporal estimates suggest that the Black Death of 1347-1351 was the main historical event responsible for the introduction and widespread dissemination of the ancestor to all currently circulating Y. pestis strains pathogenic to humans, and further indicates that contemporary Y. pestis epidemics have their origins in the medieval era. Comparisons against modern genomes reveal no unique derived positions in the medieval organism, indicating that the perceived increased virulence of the disease during the Black Death may not have been due to bacterial phenotype. These findings support the notion that factors other than microbial genetics, such as environment, vector dynamics and host susceptibility, should be at the forefront of epidemiological discussions regarding emerging Y. pestis infections.

Susceptibility of the Siberian polecat to subcutaneous and oral Yersinia pestis exposure.

PubMed

Castle, K T; Biggins, D; Carter, L G; Chu, M; Innes, K; Wimsatt, J

2001-10-01

To determine if the Siberian polecat (Mustela eversmannii) represents a suitable model for the study of plague pathogenesis and prevention in the black-footed ferret (Mustela nigripes), polecats were exposed to 10(3), 10(7), or 10(10) Yersinia pestis organisms by subcutaneous injection; an additional group was exposed to Y. pestis via ingestion of a plague-killed mouse. Plague killed 88% of polecats exposed to Y. pestis (71% mortality in the 10(3) group, 100% mortality in the 10(7) and 10(10) groups, and 83% mortality in the mouse-fed group). Within the challenged group, mean day of death post-challenge ranged from 3.6 to 7.6 days; all polecats died on or before day 12 post-challenge. Animals receiving the lowest parenteral dose survived significantly longer than those receiving higher parenteral doses. Within challenged animals, mean survival time was lower in those presenting with significant weight loss by day 3, lethargy, and low fecal output; time to onset of lethargy and other signs was also related to risk of dying and/or plague dose. Six polecats developed serum antibody titers to the Y. pestis F1 protein. Three seropositive polecats survived the initial challenge and a subsequent exposure to a plague-killed mouse, while two seropositive animals later died. This study confirms that the Siberian polecat is susceptible to plague and suggests that this species will offer an appropriate surrogate for black-footed ferrets in future plague studies and related vaccine trials.

Susceptibility to Yersinia pestis experimental infection in wild Rattus rattus, reservoir of plague in Madagascar.

PubMed

Tollenaere, C; Rahalison, L; Ranjalahy, M; Duplantier, J-M; Rahelinirina, S; Telfer, S; Brouat, C

2010-06-01

In Madagascar, the black rat, Rattus rattus, is the main reservoir of plague (Yersinia pestis infection), a disease still responsible for hundreds of cases each year in this country. This study used experimental plague challenge to assess susceptibility in wild-caught rats to better understand how R. rattus can act as a plague reservoir. An important difference in plague resistance between rat populations from the plague focus (central highlands) and those from the plague-free zone (low altitude area) was confirmed to be a widespread phenomenon. In rats from the plague focus, we observed that sex influenced plague susceptibility, with males slightly more resistant than females. Other individual factors investigated (weight and habitat of sampling) did not affect plague resistance. When infected at high bacterial dose (more than 10⁵ bacteria injected), rats from the plague focus died mainly within 3-5 days and produced specific antibodies, whereas after low-dose infection (< 5,000 bacteria), delayed mortality was observed and surviving seronegative rats were not uncommon. These results concerning plague resistance level and the course of infection in the black rat would contribute to a better understanding of plague circulation in Madagascar.

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.

Oral Vaccination against Bubonic Plague Using a Live Avirulent Yersinia pseudotuberculosis Strain ▿

PubMed Central

Blisnick, Thierry; Ave, Patrick; Huerre, Michel; Carniel, Elisabeth; Demeure, Christian E.

2008-01-01

We evaluated the possibility of using Yersinia pseudotuberculosis as a live vaccine against plague because it shares high genetic identity with Y. pestis while being much less virulent, genetically much more stable, and deliverable orally. A total of 41 Y. pseudotuberculosis strains were screened by PCR for the absence of the high pathogenicity island, the superantigens YPM, and the type IV pilus and the presence of the pYV virulence plasmid. One strain (IP32680) fulfilled these criteria. This strain was avirulent in mice upon intragastric or subcutaneous inoculation and persisted for 2 months in the mouse intestine without clinical signs of disease. IP32680 reached the mesenteric lymph nodes, spleen, and liver without causing major histological lesions and was cleared after 13 days. The antibodies produced in vaccinated animals recognized both Y. pseudotuberculosis and Y. pestis antigens efficiently. After a subcutaneous challenge with Y. pestis CO92, bacteria were found in low amounts in the organs and rarely in the blood of vaccinated animals. One oral IP32680 inoculation protected 75% of the mice, and two inoculations induced much higher antibody titers and protected 88% of the mice. Our results thus validate the concept that an attenuated Y. pseudotuberculosis strain can be an efficient, inexpensive, safe, and easy-to-produce live vaccine for oral immunization against bubonic plague. PMID:18505804

A High-Coverage Yersinia pestis Genome from a Sixth-Century Justinianic Plague Victim.

PubMed

Feldman, Michal; Harbeck, Michaela; Keller, Marcel; Spyrou, Maria A; Rott, Andreas; Trautmann, Bernd; Scholz, Holger C; Päffgen, Bernd; Peters, Joris; McCormick, Michael; Bos, Kirsten; Herbig, Alexander; Krause, Johannes

2016-11-01

The Justinianic Plague, which started in the sixth century and lasted to the mid eighth century, is thought to be the first of three historically documented plague pandemics causing massive casualties. Historical accounts and molecular data suggest the bacterium Yersinia pestis as its etiological agent. Here we present a new high-coverage (17.9-fold) Y. pestis genome obtained from a sixth-century skeleton recovered from a southern German burial site close to Munich. The reconstructed genome enabled the detection of 30 unique substitutions as well as structural differences that have not been previously described. We report indels affecting a lacl family transcription regulator gene as well as nonsynonymous substitutions in the nrdE, fadJ, and pcp genes, that have been suggested as plague virulence determinants or have been shown to be upregulated in different models of plague infection. In addition, we identify 19 false positive substitutions in a previously published lower-coverage Y. pestis genome from another archaeological site of the same time period and geographical region that is otherwise genetically identical to the high-coverage genome sequence reported here, suggesting low-genetic diversity of the plague during the sixth century in rural southern Germany. © The Author 2016. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

Gene flow in a Yersinia pestis vector, Oropsylla hirsuta, during a plague epizootic.

PubMed

Jones, Philip H; Washburn, Leigh R; Britten, Hugh B

2011-09-01

Appreciating how Yersinia pestis, the etiological agent of plague, spreads among black - tailed prairie dog (Cynomys ludovicianus) colonies (BTPD), is vital to wildlife conservation programs in North American grasslands. A little - studied aspect of the system is the role of Y. pestis vectors, i.e. fleas, play in the spreading of plague in natural settings. We investigated the genetic structure and variability of a common prairie dog flea (Oropsylla hirsuta) in BTPD colonies in order to examine dispersal patterns. Given that this research took place during a widespread plague epizootic, there was the added advantage of gaining information on the dynamics of sylvatic plague. Oropsylla hirsuta were collected from BTPD burrows in nine colonies from May 2005 to July 2005, and eight polymorphic microsatellite markers were used to generate genotypic data from them. Gene flow estimates revealed low genetic differentiation among fleas sampled from different colonies. NestedPCR plague assays confirmed the presence of Y. pestis with the average Y. pestis prevalence across all nine colonies at 12%. No significant correlations were found between the genetic variability and gene flow of O. hirsuta and Y. pestis prevalence on a per -colony basis. Oropsylla hirsuta dispersal among BTPD colonies was high, potentially explaining the rapid spread of Y. pestis in our study area in 2005 and 2006.

Protein markers for identification of Yersinia pestis and their variation related to culture

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

Wunschel, David S.; Engelmann, Heather E.; Victry, Kristin D.

2013-12-11

The detection of high consequence pathogens, such as Yersinia pestis, is well established in biodefense laboratories for bioterror situations. Laboratory protocols are well established using specified culture media and a growth temperature of 37 °C for expression of specific antigens. Direct detection of Y. pestis protein markers, without prior culture, depends on their expression. Unfortunately protein expression can be impacted by the culture medium which cannot be predicted ahead of time. Furthermore, higher biomass yields are obtained at the optimal growth temperature (i.e. 28 °C–30 °C) and therefore are more likely to be used for bulk production. Analysis of Y.more » pestis grown on several types of media at 30 °C showed that several protein markers were found to be differentially detected in different media. Analysis of the identified proteins against a comprehensive database provided an additional level of organism identification. Peptides corresponding to variable regions of some proteins could separate large groups of strains and aid in organism identification. This work illustrates the need to understand variability of protein expression for detection targets. The potential for relating expression changes of known proteins to specific media factors, even in nutrient rich and chemically complex culture medium, may provide the opportunity to draw forensic information from protein profiles.« less

Modulation of innate immune responses by Yersinia type III secretion system translocators and effectors.

PubMed

Bliska, James B; Wang, Xiaoying; Viboud, Gloria I; Brodsky, Igor E

2013-10-01

The innate immune system of mammals responds to microbial infection through detection of conserved molecular determinants called 'pathogen-associated molecular patterns' (PAMPs). Pathogens use virulence factors to counteract PAMP-directed responses. The innate immune system can in turn recognize signals generated by virulence factors, allowing for a heightened response to dangerous pathogens. Many Gram-negative bacterial pathogens encode type III secretion systems (T3SSs) that translocate effector proteins, subvert PAMP-directed responses and are critical for infection. A plasmid-encoded T3SS in the human-pathogenic Yersinia species translocates seven effectors into infected host cells. Delivery of effectors by the T3SS requires plasma membrane insertion of two translocators, which are thought to form a channel called a translocon. Studies of the Yersinia T3SS have provided key advances in our understanding of how innate immune responses are generated by perturbations in plasma membrane and other signals that result from translocon insertion. Additionally, studies in this system revealed that effectors function to inhibit innateimmune responses resulting from insertion of translocons into plasma membrane. Here, we review these advances with the goal of providing insight into how a T3SS can activate and inhibit innate immune responses, allowing a virulent pathogen to bypass host defences. © 2013 John Wiley & Sons Ltd.

Adaptive response of Yersinia pestis to extracellular effectors of innate immunity during bubonic plague.

PubMed

Sebbane, Florent; Lemaître, Nadine; Sturdevant, Daniel E; Rebeil, Roberto; Virtaneva, Kimmo; Porcella, Stephen F; Hinnebusch, B Joseph

2006-08-01

Yersinia pestis causes bubonic plague, characterized by an enlarged, painful lymph node, termed a bubo, that develops after bacterial dissemination from a fleabite site. In susceptible animals, the bacteria rapidly escape containment in the lymph node, spread systemically through the blood, and produce fatal sepsis. The fulminant progression of disease has been largely ascribed to the ability of Y. pestis to avoid phagocytosis and exposure to antimicrobial effectors of innate immunity. In vivo microarray analysis of Y. pestis gene expression, however, revealed an adaptive response to nitric oxide (NO)-derived reactive nitrogen species and to iron limitation in the extracellular environment of the bubo. Polymorphonuclear neutrophils recruited to the infected lymph node expressed abundant inducible NO synthase, and several Y. pestis homologs of genes involved in the protective response to reactive nitrogen species were up-regulated in the bubo. Mutation of one of these genes, which encodes the Hmp flavohemoglobin that detoxifies NO, attenuated virulence. Thus, the ability of Y. pestis to destroy immune cells and remain extracellular in the bubo appears to limit exposure to some but not all innate immune effectors. High NO levels induced during plague may also influence the developing adaptive immune response and contribute to septic shock.

Forensic Signature Detection of Yersinia Pestis Culturing Practices Across Institutions Using a Bayesian Network

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

Webb-Robertson, Bobbie-Jo M.; Corley, Courtney D.; McCue, Lee Ann

The field of bioforensics is focused on the analysis of evidence from a biocrime. Existing laboratory analyses can identify the specific strain of an organism in the evidence, as well signatures of the specific culture batch of organisms, such as low-frequency contaminants or indicators of growth and processing methods. To link these disparate types of physical data to potential suspects, investigators may need to identify institutions or individuals whose access to strains and culturing practices match those identified from the evidence. In this work we present a Bayesian statistical network to fuse different types of analytical measurements that predict themore » production environment of a Yersinia pestis sample under investigation with automated test processing of scientific publications to identify institutions with a history of growing Y. pestis under similar conditions. Furthermore, the textual and experimental signatures were evaluated recursively to determine the overall sensitivity of the network across all levels of false positives. We illustrate that institutions associated with several specific culturing practices can be accurately selected based on the experimental signature from only a few analytical measurements. These findings demonstrate that similar Bayesian networks can be generated generically for many organisms of interest and their deployment is not prohibitive due to either computational or experimental factors.« less

Effects of dietary Spirulina platensis on growth performance, humoral and mucosal immune responses and disease resistance in juvenile great sturgeon (Huso huso Linnaeus, 1754).

PubMed

Adel, Milad; Yeganeh, Sakineh; Dadar, Maryam; Sakai, Masahiro; Dawood, Mahmoud A O

2016-09-01

Dietary supplementation of Spirulina platensis at different levels (0% control, 2.5%, 5% and 10%) was evaluated to find out the effects on growth performance, digestive enzyme activities, humoral and skin innate immune responses and disease resistance in the great sturgeon (Huso huso). After 8 weeks of experimental trial, growth parameters, intestinal lactic acid bacteria count, protease and lipase activities were significantly high in 10% S. platensis fed group (P < 0.05). Similarly, in this group, respiratory burst activity of leucocytes and total protein of serum were also significantly high. Furthermore, supplementation of S. platensis at 5 or 10% exhibited higher serum IgM and lysozyme activity than the other experimental groups (P < 0.05). On the contrary, serum triglycerides and number of blood lymphocytes were lower in experimental groups than that of control group. Total proteins, lysozyme, protease and esterase, as well as in vitro bactericidal activity (against Streptococcus iniae, Yersinia ruckeri, Aeromonas hydrophila and Lactococcus garviea) were significantly high in skin mucus from fish fed 5% and 10% S. platensis, while, alkaline phosphatase was significantly high in fish fed 10% S. platensis (P < 0.05). Further, fish infected with Streptococcus iniae bacteria increased mortality, but it was alleviated by a diet supplemented with S. platensis. The present results demonstrate that this dietary supplementation with S. platensis (mainly at 10% level) could be useful for maintaining the overall health status of great sturgeon. Copyright © 2016 Elsevier Ltd. All rights reserved.

Multiple antigens of Yersinia pestis delivered by live recombinant attenuated Salmonella vaccine strains elicit protective immunity against plague.

PubMed

Sanapala, Shilpa; Rahav, Hannah; Patel, Hetal; Sun, Wei; Curtiss, Roy

2016-05-05

Based on our improved novel Salmonella vaccine delivery platform, we optimized the recombinant attenuated Salmonella typhimurium vaccine (RASV) χ12094 to deliver multiple Yersinia pestis antigens. These included LcrV196 (amino acids, 131-326), Psn encoded on pYA5383 and F1 encoded in the chromosome, their synthesis did not cause adverse effects on bacterial growth. Oral immunization with χ12094(pYA5383) simultaneously stimulated high antibody titers to LcrV, Psn and F1 in mice and presented complete protection against both subcutaneous (s.c.) and intranasal (i.n.) challenges with high lethal doses of Y. pestis CO92. Moreover, no deaths or other disease symptoms were observed in SCID mice orally immunized with χ12094(pYA5383) over a 60-day period. Therefore, the trivalent S. typhimurium-based live vaccine shows promise for a next-generation plague vaccine. Copyright © 2016 Elsevier Ltd. All rights reserved.