Faculty Opinions recommendation of Application of DNA microarrays to study the evolutionary genomics of Yersinia pestis and Yersinia pseudotuberculosis.

ABSTRACT Yersinia pestis, the etiologic agent of plague, has only recently evolved from Yersinia pseudotuberculosis. hfq deletion caused severe growth restriction at 37°C in Y. pestis but not in Y. pseudotuberculosis. Strains from all epidemic plague biovars were similarly affected, implicating Hfq, and likely small RNAs (sRNAs), in the unique biology of the plague bacillus.

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A quadruplex real-time PCR assay for the detection of Yersinia pestis and its plasmids

Journal of Medical Microbiology ◽

10.1099/jmm.0.47485-0 ◽

2008 ◽

Vol 57 (3) ◽

pp. 324-331 ◽

Cited By ~ 33

Author(s):

Alvin Stewart ◽

Benjamin Satterfield ◽

Marissa Cohen ◽

Kim O'Neill ◽

Richard Robison

Keyword(s):

Yersinia Pestis ◽

Real Time ◽

Real Time Pcr ◽

Yersinia Pseudotuberculosis ◽

Target Sequence ◽

Health Departments ◽

Pcr Assay ◽

Virulence Plasmids ◽

Taqman Probes ◽

Sporadic Disease

Yersinia pestis, the aetiological agent of the plague, causes sporadic disease in endemic areas of the world and is classified as a National Institute of Allergy and Infectious Diseases Category A Priority Pathogen because of its potential to be used as a bioweapon. Health departments, hospitals and government agencies need the ability to rapidly identify and characterize cultured isolates of this bacterium. Assays have been developed to perform this function; however, they are limited in their ability to distinguish Y. pestis from Yersinia pseudotuberculosis. This report describes the creation of a real-time PCR assay using Taqman probes that exclusively identifies Y. pestis using a unique target sequence of the yihN gene on the chromosome. As with other Y. pestis PCR assays, three major genes located on each of the three virulence plasmids were included: lcrV on pCD1, caf1 on pMT1 and pla on pPCP1. The quadruplex assay was validated on a collection of 192 Y. pestis isolates and 52 near-neighbour isolates. It was discovered that only 72 % of natural plague isolates from the states of New Mexico and Utah harboured all three virulence plasmids. This quadruplex assay proved to be 100 % successful in differentiating Y. pestis from all near neighbours tested and was able to reveal which of the three virulence plasmids a particular isolate possessed.

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

Microbiology ◽

10.1099/mic.0.021170-0 ◽

2009 ◽

Vol 155 (1) ◽

pp. 198-209 ◽

Cited By ~ 21

Author(s):

Scott W. Bearden ◽

Christopher Sexton ◽

Joshua Pare ◽

Janet M. Fowler ◽

Cindy G. Arvidson ◽

...

Keyword(s):

Yersinia Pestis ◽

Yersinia Pseudotuberculosis ◽

Amino Acid Position ◽

Enzymic Activity ◽

Broad Host Range ◽

Missense Mutations ◽

Tissue Invasion ◽

Muroid Rodents ◽

Glucose 6 Phosphate Dehydrogenase ◽

Reduced Activity

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 k cat but not K m 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.

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Opinion 60: Rejection of the Name Yersinia pseudotuberculosis subsp. pestis (van Loghem) Bercovier et al. 1981 and Conservation of the Name Yersinia pestis (Lehmann and Neumann) van Loghem 1944 for the Plague Bacillus: Judicial Commission of the International Committee on Systematic Bacteriology

International Journal of Systematic Bacteriology ◽

10.1099/00207713-35-4-540 ◽

1985 ◽

Vol 35 (4) ◽

pp. 540-540 ◽

Cited By ~ 14

Keyword(s):

Yersinia Pestis ◽

Yersinia Pseudotuberculosis ◽

International Committee ◽

Systematic Bacteriology

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Identification of gmhA, a Yersinia pestis Gene Required for Flea Blockage, by Using a Caenorhabditis elegans Biofilm System

Infection and Immunity ◽

10.1128/iai.73.11.7236-7242.2005 ◽

2005 ◽

Vol 73 (11) ◽

pp. 7236-7242 ◽

Cited By ~ 55

Author(s):

Creg Darby ◽

Sandya L. Ananth ◽

Li Tan ◽

B. Joseph Hinnebusch

Keyword(s):

Caenorhabditis Elegans ◽

Yersinia Pestis ◽

Biofilm Formation ◽

Yersinia Pseudotuberculosis ◽

C Elegans ◽

Transposon Insertion ◽

Insertion Mutants ◽

Random Screening

ABSTRACT Yersinia pestis, the cause of bubonic plague, blocks feeding by its vector, the flea. Recent evidence indicates that blockage is mediated by an in vivo biofilm. Y. pestis and the closely related Yersinia pseudotuberculosis also make biofilms on the cuticle of the nematode Caenorhabditis elegans, which block this laboratory animal's feeding. Random screening of Y. pseudotuberculosis transposon insertion mutants with a C. elegans biofilm assay identified gmhA as a gene required for normal biofilms. gmhA encodes phosphoheptose isomerase, an enzyme required for synthesis of heptose, a conserved component of lipopolysaccharide and lipooligosaccharide. A Y. pestis gmhA mutant was constructed and was severely defective for C. elegans biofilm formation and for flea blockage but only moderately defective in an in vitro biofilm assay. These results validate use of the C. elegans biofilm system to identify genes and pathways involved in Y. pestis flea blockage.

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