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Nikiforov KA, Kukleva LM, Al’khova ZV, Naryshkina EA, Guseva NP, Eroshenko GA, Tokmakova EG, Balakhonov SV, Kutyrev VV. Phylogeographic Analysis of Yersinia pestis Subspecies ulegeica Strains. RUSS J GENET+ 2020. [DOI: 10.1134/s1022795420060071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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2
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Suntsov VV. Quantum Speciation of Yersinia pestis Plague Microbe in a Heteroimmune Environment: In the Populations of Hibernating Tarbagan Marmots (Marmota sibirica). CONTEMP PROBL ECOL+ 2018. [DOI: 10.1134/s199542551804008x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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3
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Perry RD, Fetherston JD. Yersiniabactin iron uptake: mechanisms and role in Yersinia pestis pathogenesis. Microbes Infect 2011; 13:808-17. [PMID: 21609780 DOI: 10.1016/j.micinf.2011.04.008] [Citation(s) in RCA: 103] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2011] [Accepted: 04/26/2011] [Indexed: 12/31/2022]
Abstract
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 Yersinia pestis to cause bubonic plague and important in pneumonic plague as well. However, the ability to cause fatal septicemic plague is independent of Ybt.
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Affiliation(s)
- Robert D Perry
- Department of Microbiology, Immunology, and Molecular Genetics, MS415 Medical Center, University of Kentucky, Lexington, KY 40536-0298, USA.
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Eroshenko GA, Vidyaeva NA, Kutyrev VV. Comparative analysis of biofilm formation by main and nonmain subspecies Yersinia pestis strains. ACTA ACUST UNITED AC 2010; 59:513-20. [PMID: 20618849 DOI: 10.1111/j.1574-695x.2010.00719.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The biofilm-forming phenotype of 14 isolates from four 'nonmain' subspecies of Yersinia pestis was compared with eight isolates from the more commonly studied 'main' or epidemic subspecies of Y. pestis in this study. The four nonmain subspecies are more geographically limited, and are associated with certain mammalian hosts and regions of the Caucasus and Central Asia, whereas the main subspecies spread worldwide during the historic plague pandemics. With the main subspecies pestis, pigmentation on Congo red medium (CR(+)) correlated with biofilm formation on both abiotic and biotic surfaces. Main subspecies pestis strains that do not produce pigmentation on Congo red medium (CR(-)) have a deletion that includes the hmsF and hmsS genes known to be required for biofilm formation. CR(-) strains of the nonmain subspecies, altaica and ulegeica, differed however from pestis and, while defective for biofilms on the two surfaces, both had intact hmsF and hmsS genes. The presence of rcsA was also investigated and results showed that it occurred with a 30-bp insertion in all forms of the subspecies. These findings suggest that biofilms are regulated differently in altaica and ulegeica than they are in pestis and also indicate that the rcsA pseudogene arose early in Y. pestis evolution, increasing the ability of the strain to form biofilm and thereby increasing its effective transmission.
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Affiliation(s)
- Galina A Eroshenko
- Russian Anti-Plague Research Institute Microbe, Universitetskaya, Saratov, Russian Federation.
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Vetter SM, Eisen RJ, Schotthoefer AM, Montenieri JA, Holmes JL, Bobrov AG, Bearden SW, Perry RD, Gage KL. Biofilm formation is not required for early-phase transmission of Yersinia pestis. MICROBIOLOGY-SGM 2010; 156:2216-2225. [PMID: 20395271 PMCID: PMC3068684 DOI: 10.1099/mic.0.037952-0] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Early-phase transmission (EPT) is a recently described model of plague transmission that explains the rapid spread of disease from flea to mammal host during an epizootic. Unlike the traditional blockage-dependent model of plague transmission, EPT can occur when a flea takes its first blood meal after initially becoming infected by feeding on a bacteraemic host. Blockage of the flea gut results from biofilm formation in the proventriculus, mediated by the gene products found in the haemin storage (hms) locus of the Yersinia pestis chromosome. Although biofilms are required for blockage-dependent transmission, the role of biofilms in EPT has yet to be determined. An artificial feeding system was used to feed Xenopsylla cheopis and Oropsylla montana rat blood spiked with the parental Y. pestis strain KIM5(pCD1)+, two different biofilm-deficient mutants (ΔhmsT, ΔhmsR), or a biofilm-overproducer mutant (ΔhmsP). Infected fleas were then allowed to feed on naïve Swiss Webster mice for 1–4 days after infection, and the mice were monitored for signs of infection. We also determined the bacterial loads of each flea that fed upon naïve mice. Biofilm-defective mutants transmitted from X. cheopis and O. montana as efficiently as the parent strain, whereas the EPT efficiency of fleas fed the biofilm-overproducing strain was significantly less than that of fleas fed either the parent or a biofilm-deficient strain. Fleas infected with a biofilm-deficient strain harboured lower bacterial loads 4 days post-infection than fleas infected with the parent strain. Thus, defects in biofilm formation did not prevent flea-borne transmission of Y. pestis in our EPT model, although biofilm overproduction inhibited efficient EPT. Our results also indicate, however, that biofilms may play a role in infection persistence in the flea.
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Affiliation(s)
- Sara M Vetter
- Bacterial Diseases Branch, Division of Vector Borne Diseases, National Center for Enteric and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, 3150 Rampart Rd, Fort Collins, CO 80521, USA
| | - Rebecca J Eisen
- Bacterial Diseases Branch, Division of Vector Borne Diseases, National Center for Enteric and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, 3150 Rampart Rd, Fort Collins, CO 80521, USA
| | - Anna M Schotthoefer
- Bacterial Diseases Branch, Division of Vector Borne Diseases, National Center for Enteric and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, 3150 Rampart Rd, Fort Collins, CO 80521, USA
| | - John A Montenieri
- Bacterial Diseases Branch, Division of Vector Borne Diseases, National Center for Enteric and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, 3150 Rampart Rd, Fort Collins, CO 80521, USA
| | - Jennifer L Holmes
- Bacterial Diseases Branch, Division of Vector Borne Diseases, National Center for Enteric and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, 3150 Rampart Rd, Fort Collins, CO 80521, USA
| | - Alexander G Bobrov
- Department of Microbiology, Immunology and Molecular Genetics, University of Kentucky, MS415 Medical Center, Lexington, KY 40536, USA
| | - Scott W Bearden
- Bacterial Diseases Branch, Division of Vector Borne Diseases, National Center for Enteric and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, 3150 Rampart Rd, Fort Collins, CO 80521, USA
| | - Robert D Perry
- Department of Microbiology, Immunology and Molecular Genetics, University of Kentucky, MS415 Medical Center, Lexington, KY 40536, USA
| | - Kenneth L Gage
- Bacterial Diseases Branch, Division of Vector Borne Diseases, National Center for Enteric and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, 3150 Rampart Rd, Fort Collins, CO 80521, USA
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Abstract
The potential application of Yersinia pestis for bioterrorism emphasizes the urgent need to develop more effective vaccines against airborne infection. The current status of plague vaccines has been reviewed. The present emphasis is on subunit vaccines based on the F1 and LcrV antigens. These provide good protection in animal models but may not protect against F1 strains with modifications to the type III secretion system. The duration of protection against pneumonic infection is also uncertain. Other strategies under investigation include defined live-attenuated vaccines, DNA vaccines, mucosal delivery systems and heterologous immunization. The live-attenuated strain Y. pestis EV NIIEG protects against aerosol challenge in animal models and, with further modification to reduce residual virulence and to optimize respiratory protection, it could provide a shortcut to improved vaccines. The regulatory problems inherent in licensing vaccines for which efficacy data are unavailable and their possible solutions are discussed herein.
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Affiliation(s)
- Valentina A Feodorova
- Scientific and Research Institute for Medical and Veterinary Biotechnologies, Russia-Switzerland, Branch in Saratov, 9 Proviantskaya Street, Box 1580, Saratov 410028, Russia.
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Abu Khweek A, Fetherston JD, Perry RD. Analysis of HmsH and its role in plague biofilm formation. MICROBIOLOGY-SGM 2010; 156:1424-1438. [PMID: 20093287 DOI: 10.1099/mic.0.036640-0] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The Yersinia pestis Hms(+) phenotype is a manifestation of biofilm formation that causes adsorption of Congo red and haemin at 26 degrees C but not at 37 degrees C. This phenotype is required for blockage of the proventricular valve of the oriental rat flea and plays a role in transmission of bubonic plague from fleas to mammals. Genes responsible for this phenotype are located in three separate operons, hmsHFRS, hmsT and hmsP. HmsH and HmsF are outer membrane (OM) proteins, while the other four Hms proteins are located in the inner membrane. According to the Hidden Markov Method-based predictor, HmsH has a large N terminus in the periplasm, a beta-barrel structure with 16 beta-strands that traverse the OM, eight surface-exposed loops, and seven short turns connecting the beta-strands on the periplasmic side. Here, we demonstrate that HmsH is a heat-modifiable protein, a characteristic of other beta-barrel proteins, thereby supporting the bioinformatics analysis. Alanine scanning mutagenesis was used to identify conserved amino acids in the HmsH-like family that are critical for the function of HmsH in biofilm formation. Of 23 conserved amino acids mutated, four residues affected HmsH function and three likely caused protein instability. We used formaldehyde cross-linking to demonstrate that HmsH interacts with HmsF but not with HmsR, HmsS, HmsT or HmsP. Loss-of-function HmsH variants with single alanine substitutions retained their beta-structure and interaction with HmsF. Finally, using a polar hmsH : : mini-kan mutant, we demonstrated that biofilm development is not important for the pathogenesis of bubonic or pneumonic plague in mice.
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Affiliation(s)
- Arwa Abu Khweek
- Department of Microbiology, Immunology, and Molecular Genetics, University of Kentucky, 800 Rose St., Lexington, KY, USA
| | - Jacqueline D Fetherston
- Department of Microbiology, Immunology, and Molecular Genetics, University of Kentucky, 800 Rose St., Lexington, KY, USA
| | - Robert D Perry
- Department of Microbiology, Immunology, and Molecular Genetics, University of Kentucky, 800 Rose St., Lexington, KY, USA
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The smpB-ssrA mutant of Yersinia pestis functions as a live attenuated vaccine to protect mice against pulmonary plague infection. Infect Immun 2010; 78:1284-93. [PMID: 20065026 DOI: 10.1128/iai.00976-09] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The bacterial SmpB-SsrA system is a highly conserved translational quality control mechanism that helps maintain the translational machinery at full capacity. Here we present evidence to demonstrate that the smpB-ssrA genes are required for pathogenesis of Yersinia pestis, the causative agent of plague. We found that disruption of the smpB-ssrA genes leads to reduction in secretion of the type III secretion-related proteins YopB, YopD, and LcrV, which are essential for virulence. Consistent with these observations, the smpB-ssrA mutant of Y. pestis was severely attenuated in a mouse model of infection via both the intranasal and intravenous routes. Most significantly, intranasal vaccination of mice with the smpB-ssrA mutant strain of Y. pestis induced a strong antibody response. The vaccinated animals were well protected against subsequent lethal intranasal challenges with virulent Y. pestis. Taken together, our results indicate that the smpB-ssrA mutant of Y. pestis possesses the desired qualities for a live attenuated cell-based vaccine against pneumonic plague.
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Chain PSG, Hu P, Malfatti SA, Radnedge L, Larimer F, Vergez LM, Worsham P, Chu MC, Andersen GL. Complete genome sequence of Yersinia pestis strains Antiqua and Nepal516: evidence of gene reduction in an emerging pathogen. J Bacteriol 2006; 188:4453-63. [PMID: 16740952 PMCID: PMC1482938 DOI: 10.1128/jb.00124-06] [Citation(s) in RCA: 162] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Yersinia pestis, the causative agent of bubonic and pneumonic plagues, has undergone detailed study at the molecular level. To further investigate the genomic diversity among this group and to help characterize lineages of the plague organism that have no sequenced members, we present here the genomes of two isolates of the "classical" antiqua biovar, strains Antiqua and Nepal516. The genomes of Antiqua and Nepal516 are 4.7 Mb and 4.5 Mb and encode 4,138 and 3,956 open reading frames, respectively. Though both strains belong to one of the three classical biovars, they represent separate lineages defined by recent phylogenetic studies. We compare all five currently sequenced Y. pestis genomes and the corresponding features in Yersinia pseudotuberculosis. There are strain-specific rearrangements, insertions, deletions, single nucleotide polymorphisms, and a unique distribution of insertion sequences. We found 453 single nucleotide polymorphisms in protein-coding regions, which were used to assess the evolutionary relationships of these Y. pestis strains. Gene reduction analysis revealed that the gene deletion processes are under selective pressure, and many of the inactivations are probably related to the organism's interaction with its host environment. The results presented here clearly demonstrate the differences between the two biovar antiqua lineages and support the notion that grouping Y. pestis strains based strictly on the classical definition of biovars (predicated upon two biochemical assays) does not accurately reflect the phylogenetic relationships within this species. A comparison of four virulent Y. pestis strains with the human-avirulent strain 91001 provides further insight into the genetic basis of virulence to humans.
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Affiliation(s)
- Patrick S G Chain
- Biosciences Directorate, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
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Patel CN, Wortham BW, Lines JL, Fetherston JD, Perry RD, Oliveira MA. Polyamines are essential for the formation of plague biofilm. J Bacteriol 2006; 188:2355-63. [PMID: 16547021 PMCID: PMC1428407 DOI: 10.1128/jb.188.7.2355-2363.2006] [Citation(s) in RCA: 144] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We provide the first evidence for a link between polyamines and biofilm levels in Yersinia pestis, the causative agent of plague. Polyamine-deficient mutants of Y. pestis were generated with a single deletion in speA or speC and a double deletion mutant. The genes speA and speC code for the biosynthetic enzymes arginine decarboxylase and ornithine decarboxylase, respectively. The level of the polyamine putrescine compared to the parental speA+ speC+ strain (KIM6+) was depleted progressively, with the highest levels found in the Y. pestis DeltaspeC mutant (55% reduction), followed by the DeltaspeA mutant (95% reduction) and the DeltaspeA DeltaspeC mutant (>99% reduction). Spermidine, on the other hand, remained constant in the single mutants but was undetected in the double mutant. The growth rates of mutants with single deletions were not altered, while the DeltaspeA DeltaspeC mutant grew at 65% of the exponential growth rate of the speA+ speC+ strain. Biofilm levels were assayed by three independent measures: Congo red binding, crystal violet staining, and confocal laser scanning microscopy. The level of biofilm correlated to the level of putrescine as measured by high-performance liquid chromatography-mass spectrometry and as observed in a chemical complementation curve. Complementation of the DeltaspeA DeltaspeC mutant with speA showed nearly full recovery of biofilm to levels observed in the speA+ speC+ strain. Chemical complementation of the double mutant and recovery of the biofilm defect were only observed with the polyamine putrescine.
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Affiliation(s)
- Chandra N Patel
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY 40536-0082, USA
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12
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Bobrov AG, Kirillina O, Perry RD. The phosphodiesterase activity of the HmsP EAL domain is required for negative regulation of biofilm formation in Yersinia pestis. FEMS Microbiol Lett 2005; 247:123-30. [PMID: 15935569 DOI: 10.1016/j.femsle.2005.04.036] [Citation(s) in RCA: 138] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2005] [Revised: 04/13/2005] [Accepted: 04/26/2005] [Indexed: 11/22/2022] Open
Abstract
In Yersinia pestis, biofilm formation is stimulated by HmsT, a GGDEF-domain containing protein that synthesizes cyclic-di-GMP (c-di-GMP), and inhibited by HmsP, an EAL-domain protein. Only the EAL-domain portion of HmsP is required to inhibit biofilm formation. The EAL domain of HmsP was purified as a 6XHis-tag fusion protein and demonstrated to have phosphodiesterase activity using bis(p-nitrophenyl) phosphate (bis-pNPP) as a substrate. This enzymatic activity was strictly manganese dependent. A critical residue (E506) of HmsP within the EAL domain, that is required for inhibition of biofilm formation, is also essential for this phosphodiesterase activity. While the proposed function of EAL-domain proteins is to linearize c-di-GMP, this is a direct demonstration of the required phosphodiesterase activity of a purified EAL-domain protein.
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Affiliation(s)
- Alexander G Bobrov
- Department of Microbiology, Immunology and Molecular Genetics, University of Kentucky, Lexington, KY 40536-0298, USA
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Simm R, Fetherston JD, Kader A, Römling U, Perry RD. Phenotypic convergence mediated by GGDEF-domain-containing proteins. J Bacteriol 2005; 187:6816-23. [PMID: 16166544 PMCID: PMC1251569 DOI: 10.1128/jb.187.19.6816-6823.2005] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
GGDEF domain-containing proteins have been implicated in bacterial signal transduction and synthesis of the second messenger molecule cyclic-di-GMP. A number of GGDEF proteins are involved in controlling the formation of extracellular matrices. AdrA (Salmonella enterica serovar Typhimurium) and HmsT (Yersinia pestis) contain GGDEF domains and are required for extracellular cellulose production and biofilm formation, respectively. Here we show that hmsT is able to restore cellulose synthesis to a Salmonella serovar Typhimurium adrA mutant and that adrA can replace hmsT in Y. pestis Hms-dependent biofilm formation. Like Y. pestis HmsT overproducers, Y. pestis cells carrying adrA under the control of an arabinose-inducible promoter produced substantial biofilms in the presence of arabinose. Finally, we demonstrate that HmsT is involved in the synthesis of cyclic di-GMP.
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Affiliation(s)
- Roger Simm
- Department of Microbiology, Immunology, and Molecular Genetics, MS415 Medical Center, University of Kentucky, Lexington, KY 40536-0298, USA
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Kirillina O, Fetherston JD, Bobrov AG, Abney J, Perry RD. HmsP, a putative phosphodiesterase, and HmsT, a putative diguanylate cyclase, control Hms-dependent biofilm formation in Yersinia pestis. Mol Microbiol 2004; 54:75-88. [PMID: 15458406 DOI: 10.1111/j.1365-2958.2004.04253.x] [Citation(s) in RCA: 186] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The Hms(+) phenotype of Yersinia pestis promotes the binding of haemin or Congo red (CR) to the cell surface at temperatures below 34 degrees C. We previously demonstrated that temperature regulation of the Hms(+) phenotype is not controlled at the level of transcription. Instead, HmsH, HmsR and HmsT are degraded upon a temperature shift from 26 degrees C to 37 degrees C. We used random transposon mutagenesis to identify new genes involved in the temperature-regulated expression of the Hms phenotype. One of these genes, which we designated hmsP, encodes a putative phosphodiesterase with a conserved EAL motif. Mutations in hmsP caused formation of red colonies on CR plates at 26 degrees C and 37 degrees C. Strains complemented with hmsP(+) on a plasmid form white colonies at both temperatures. We used a crystal violet assay and confocal laser scanning microscopy to demonstrate Hms-dependent biofilm formation by Y. pestis cells. Y. pestis Hms(+) strains grown at 26 degrees C but not at 37 degrees C form a biofilm on borosilicate glass surfaces. Strains that either overexpress HmsT (a GGDEF domain protein) or have a mutation in hmsP produced an extremely thick biofilm. Alanine substitutions for each of the GGEE residues (amino acids 296-299) of HmsT as well as the E506 and L508 residues of HmsP caused a loss of function. We propose that HmsT and HmsP together control the amount of biofilm produced in Y. pestis. Degradation of HmsT at 37 degrees C may be a critical factor in controlling the temperature-dependent expression of the Hms biofilm.
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Affiliation(s)
- Olga Kirillina
- Department of Microbiology, Immunology, and Molecular Genetics, MS415 Medical Center, University of Kentucky, Lexington, KY 40536-0298, USA
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Perry RD, Bobrov AG, Kirillina O, Jones HA, Pedersen L, Abney J, Fetherston JD. Temperature regulation of the hemin storage (Hms+) phenotype of Yersinia pestis is posttranscriptional. J Bacteriol 2004; 186:1638-47. [PMID: 14996794 PMCID: PMC355957 DOI: 10.1128/jb.186.6.1638-1647.2004] [Citation(s) in RCA: 97] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In Yersinia pestis, the Congo red (and hemin) binding that is characteristic of the Hms+ phenotype occurs at temperatures up to 34 degrees C but not at higher temperatures. Manifestation of the Hms+ phenotype requires at least five proteins (HmsH, -F, -R, -S, and -T) that are organized into two separate operons: hmsHFRS and hmsT. HmsH and HmsF are outer membrane proteins, while HmsR, HmsS, and HmsT are predicted to be inner membrane proteins. We have used transcriptional reporter constructs, RNA dot blots, and Western blots to examine the expression of hms operons and proteins. Our studies indicate that transcription from the hmsHFRS and hmsT promoters is not regulated by the iron status of the cells, growth temperature, or any of the Hms proteins. In addition, the level of mRNA for both operons is not significantly affected by growth temperature. However, protein levels of HmsH, HmsR, and HmsT in cells grown at 37 degrees C are very low compared to those in cells grown at 26 degrees C, while the amounts of HmsF and HmsS show only a moderate reduction at the higher growth temperature. Neither the Pla protease nor a putative endopeptidase (Y2360) encoded upstream of hmsH is essential for temperature regulation of the Hms+ phenotype. However, HmsT at 37 degrees C is sensitive to degradation by Lon and/or ClpPX. Thus, the stability of HmsH, HmsR, and HmsT proteins likely plays a role in temperature regulation of the Hms+ phenotype of Y. pestis.
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Affiliation(s)
- Robert D Perry
- Department of Microbiology, Immunology, and Molecular Genetics, University of Kentucky, Lexington, Kentucky 40536, USA.
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Kutyrev VV, Protsenko OA, Smirnov GB, Boolgakova E, Kukleva LM, Zudina IV, Vidyaeva NA, Koozmichenko I. Yersinia pestis from natural foci. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2003; 529:313-6. [PMID: 12756777 DOI: 10.1007/0-306-48416-1_59] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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Bobrov AG, Geoffroy VA, Perry RD. Yersiniabactin production requires the thioesterase domain of HMWP2 and YbtD, a putative phosphopantetheinylate transferase. Infect Immun 2002; 70:4204-14. [PMID: 12117929 PMCID: PMC128149 DOI: 10.1128/iai.70.8.4204-4214.2002] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2002] [Revised: 03/15/2002] [Accepted: 05/02/2002] [Indexed: 12/30/2022] Open
Abstract
One requirement for the pathogenesis of Yersinia pestis, the causative agent of bubonic plague, is the yersiniabactin (Ybt) siderophore-dependent iron transport system that is encoded within a high-pathogenicity island (HPI) within the pgm locus of the Y. pestis chromosome. Nine gene products within the HPI have demonstrated functions in the nonribosomal peptide synthesis (NRPS)/polyketide (PK) synthesis or transport of Ybt. NRPS/PK synthetase or synthase enzymes are generally activated by phosphopantetheinylation. However, no products with similarities to known phosphopantetheinyl (P-pant) transferases were found within the pgm locus. We have identified a gene, ybtD, encoded outside the HPI and pgm locus, that is necessary for function of the Ybt system and has similarities to other P-pant transferases such as EntD of Escherichia coli. A deletion within ybtD yielded a strain (KIM6-2085+) defective in siderophore production. This strain was unable to grow on iron-deficient media at 37 degrees C but could be cross-fed by culture supernatants from Ybt-producing strains of Y. pestis. The promoter region of ybtD was fused to lacZ; beta-galactosidase expression from this reporter was not regulated by the iron status of the bacterial cells or by YbtA, a positive regulator of other genes of the ybt system. The ybtD mutant failed to express indicator Ybt proteins (high-molecular-weight protein 1 [HMWP1], HMWP2, and Psn), a pattern similar to those seen with several other ybt biosynthetic mutants. In contrast, cells containing a single amino acid substitution (S2908A) in the terminal thioesterase domain of HMWP2 failed to exhibit any ybt regulatory defects but did not elaborate extracellular Ybt under iron-deficient conditions.
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Affiliation(s)
- Alexander G Bobrov
- Department of Microbiology, Immunology, and Molecular Genetics, University of Kentucky, Lexington 40536-0084, USA
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Geoffroy VA, Fetherston JD, Perry RD. Yersinia pestis YbtU and YbtT are involved in synthesis of the siderophore yersiniabactin but have different effects on regulation. Infect Immun 2000; 68:4452-61. [PMID: 10899842 PMCID: PMC98347 DOI: 10.1128/iai.68.8.4452-4461.2000] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
One prerequisite for the virulence of Yersinia pestis, causative agent of bubonic plague, is the yersiniabactin (Ybt) siderophore-dependent iron transport system that is encoded within a high-pathogenicity island (HPI) within the pgm locus of the Y. pestis chromosome. Several gene products within the HPI have demonstrated functions in the synthesis or transport of Ybt. Here we examine the roles of ybtU and ybtT. In-frame mutations in ybtT or ybtU yielded strains defective in siderophore production. Mutant strains were unable to grow on iron-deficient media at 37 degrees C but could be cross-fed by culture supernatants from a Ybt-producing strain of Y. pestis. The ybtU mutant failed to express four indicator Ybt proteins (HMWP1, HMWP2, YbtE, and Psn), a pattern similar to those for other ybt biosynthetic mutants. In contrast, strains carrying mutations in ybtT or ybtS (a previously identified gene required for Ybt biosynthesis) produced all four proteins at wild-type levels under iron-deprived conditions. To assess the effects of ybtT, -U, and -S mutations on transcription of ybt genes, reporter plasmids with ybtP or psn promoters controlling lacZ expression were introduced into these mutants. Normal iron-regulated beta-galactosidase activity was observed in the ybtT and ybtS mutants, whereas a significant loss of expression occurred in the DeltaybtU strain. These results show that ybtT and ybtU genes are involved in the biosynthesis of the Ybt siderophore and that a ybtU mutation but not ybtT or ybtS mutations affects transcription from the ybtP and psn promoters.
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Affiliation(s)
- V A Geoffroy
- Department of Microbiology and Immunology, University of Kentucky, Lexington, Kentucky, USA
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Iqbal SS, Chambers JP, Goode MT, Valdes JJ, Brubaker RR. Detection of Yersinia pestis by pesticin fluorogenic probe-coupled PCR. Mol Cell Probes 2000; 14:109-14. [PMID: 10799272 DOI: 10.1006/mcpr.2000.0295] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The <<Taq Man>> assay (PE Applied Biosystems) combines PCR with concomitant release of fluorogenic nucleotides for immediate product detection by fluorometry. Yersinia pestis, the etiological agent of bubonic plague, expresses species-specific genes known to be located on two unique plasmids (9.6-kb pPCP and 100.9-kb pMT). Pesticin (pst) is a unique gene located on pPCP which encodes for a bacteriocin. Using fluorogenic probe coupled PCR as few as three copies of pst targets were detected from total Y. pestis genomic DNA. The pst probe used in this report was positive only for pesticinogenic isolates and did not show complementarity with Yersiniae nor with other bacteria targeted in this study suggesting, that the pst probe is very specific for Y. pestis. Under optimal conditions of Mg(2+)concentration and thermal cycle number, addition of extraneous DNA to respective assay mixtures had no effect on detection.
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Affiliation(s)
- S S Iqbal
- Division of Life Sciences, University of Texas at San Antonio, 78249, USA
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20
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Buchrieser C, Rusniok C, Frangeul L, Couve E, Billault A, Kunst F, Carniel E, Glaser P. The 102-kilobase pgm locus of Yersinia pestis: sequence analysis and comparison of selected regions among different Yersinia pestis and Yersinia pseudotuberculosis strains. Infect Immun 1999; 67:4851-61. [PMID: 10456941 PMCID: PMC96819 DOI: 10.1128/iai.67.9.4851-4861.1999] [Citation(s) in RCA: 106] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
We report the complete 119,443-bp sequence of the pgm locus from Yersinia pestis and its flanking regions. Sequence analysis confirms that the 102-kb unstable pgm locus is composed of two distinct parts: the pigmentation segment and a high-pathogenicity island (HPI) which carries virulence genes involved in iron acquisition (yersiniabactin biosynthetic gene cluster). Within the HPI, three genes coding for proteins related to phage proteins were uncovered. They are located at both extremities indicating that the entire HPI was acquired en bloc by phage-mediated horizontal transfer. We identified, within the pigmentation segment, two novel loci that may be involved in virulence: a fimbriae gene cluster and a locus probably encoding a two component regulatory system similar to the BvgAS regulatory system of Bordetella pertussis. Three genes containing frameshift mutations and two genes interrupted by insertion element insertion were found within this region. To investigate diversity among different Y. pestis and Yersinia pseudotuberculosis strains, the sequence of selected regions of the pgm locus and flanking regions were compared from 20 different Y. pestis and 10 Y. pseudotuberculosis strains. The results showed that the genes interrupted in Y. pestis are intact in Y. pseudotuberculosis. However, one of these mutations, in the bvgS homologue, is only present in Y. pestis strains of biovar Orientalis and not in those of the biovars Antiqua and Medievalis. The results obtained by analysis of variable positions in the sequence are in accordance with historical records, confirming that biovar Orientalis is the most recent lineage. Furthermore, sequence comparisons among 29 Yersinia strains suggest that Y. pestis is a recently emerged pathogen that is probably entering the initial phase of reductive evolution.
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Affiliation(s)
- C Buchrieser
- Laboratoire de Génomique des Microorganismes Pathogènes, Institut Pasteur, 75724 Paris Cedex 15, France.
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21
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Iqbal SS, Chambers JP, Brubaker RR, Goode MT, Valdes JJ. Detection of Yersinia pestis using branched DNA. Mol Cell Probes 1999; 13:315-20. [PMID: 10441205 DOI: 10.1006/mcpr.1999.0255] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In contrast to target amplification methods, e.g. polymerase chain reaction, the branched DNA (bDNA) signal amplification method quantitates target nucleic acid at physiological levels, involving a series of hybridization reactions without thermal cycling. In this report, we describe a modification of the bDNA assay in which a <<concatenated>> preamplifier oligonucleotide (206 mer) is used in concert with ELISA and light addressable potentiometric sensor (LAPS) formats to detect the plasminogen activator (pla) gene of Yersinia pestis, the etiological agent of plague. Pla is encoded by a 9.6-kb plasmid pPCP, which is essential for virulence. The detection limit of the bDNA-ELISA and LAPS assays is less than 10 000 and 1000 molecules of Y. pestis plasmid DNA, respectively.
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Affiliation(s)
- S S Iqbal
- Division of Life Sciences, University of Texas at San Antonio, San Antonio, TX, 78249, USA
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22
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Fetherston JD, Bertolino VJ, Perry RD. YbtP and YbtQ: two ABC transporters required for iron uptake in Yersinia pestis. Mol Microbiol 1999; 32:289-99. [PMID: 10231486 DOI: 10.1046/j.1365-2958.1999.01348.x] [Citation(s) in RCA: 135] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Yersinia pestis, the causative agent of plague, makes a siderophore termed yersiniabactin (Ybt), which it uses to obtain iron during growth at 37 degrees C. The genes required for the synthesis and utilization of Ybt are located within a large, unstable region of the Y. pestis chromosome called the pgm locus. Within the pgm locus, just upstream of a gene (ybtA) that regulates expression of the Ybt receptor and biosynthetic genes, is an operon consisting of 4 genes - ybtP, ybtQ, ybtX and ybtS. Transcription of the ybtPQXS operon is repressed by Fur and activated by YbtA. The product of ybtX is predicted to be an exceedingly hydrophobic cytoplasmic membrane protein that does not appear to contribute any vital function to Ybt biosynthesis or utilization in vitro. ybtP and ybtQ encode putative members of the traffic ATPase/ABC transporter family. YbtP and YbtQ are structurally unique among the subfamily of ABC transporters associated with iron transport, in that they both contain an amino-terminal membrane-spanning domain and a carboxy-terminal ATPase. Cells with mutations in ybtP or ybtQ still produced Ybt but were impaired in their ability to grow at 37 degrees C under iron-deficient conditions, indicating that YbtP and YbtQ are needed for iron uptake. In addition, a ybtP mutant showed reduced iron accumulation and was avirulent in mice by a subcutaneous route of infection that mimics flea transmission of bubonic plague.
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Affiliation(s)
- J D Fetherston
- Department of Microbiology and Immunology, University of Kentucky, Lexington, KY 40536-0084, USA
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23
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Buchrieser C, Prentice M, Carniel E. The 102-kilobase unstable region of Yersinia pestis comprises a high-pathogenicity island linked to a pigmentation segment which undergoes internal rearrangement. J Bacteriol 1998; 180:2321-9. [PMID: 9573181 PMCID: PMC107171 DOI: 10.1128/jb.180.9.2321-2329.1998] [Citation(s) in RCA: 110] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Several pathogenicity islands have recently been identified in different bacterial species, including a high-pathogenicity island (HPI) in Yersinia enterocolitica 1B. In Y. pestis, a 102-kb chromosomal fragment (pgm locus) that carries genes involved in iron acquisition and colony pigmentation can be deleted en bloc. In this study, characterization and mapping of the 102-kb region of Y. pestis 6/69 were performed to determine if this unstable region is a pathogenicity island. We found that the 102-kb region of Y. pestis is composed of two clearly distinct regions: an approximately 35-kb iron acquisition segment, which is an HPI per se, linked to an approximately 68-kb pigmentation segment. This linkage was preserved in all of the Y. pestis strains studied. However, several nonpigmented Y. pestis strains harboring an irp2 gene have been previously identified, suggesting that the pigmentation segment is independently mobile. Comparison of the physical map of the 102-kb region of these strains with that of strain 6/69 and complementation experiments were carried out to determine the genetic basis of this phenomenon. We demonstrate that several different mechanisms involving mutations and various-size deletions are responsible for the nonpigmented phenotype in the nine strains studied. However, no deletion corresponded exactly to the pigmentation segment. The 102-kb region of Y. pestis is an evolutionarily stable linkage of an HPI with a pigmentation segment in a region of the chromosome prone to rearrangement in vitro.
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Affiliation(s)
- C Buchrieser
- Unité de Bactériologie Moléculaire et Médicale, Laboratoire des Yersinia, Institut Pasteur, Paris, France
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24
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Lillard JW, Fetherston JD, Pedersen L, Pendrak ML, Perry RD. Sequence and genetic analysis of the hemin storage (hms) system of Yersinia pestis. Gene 1997; 193:13-21. [PMID: 9249062 DOI: 10.1016/s0378-1119(97)00071-1] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
We have sequenced a region from the pigmentation (pgm) locus of Yersinia pestis KIM6+ that is identified with the exogenous hemin storage (Hms+) phenotype in cells grown at 26 but not at 37 degrees C. The hmsHFRS locus encodes a putative polycistronic operon, with hmsH encoding an outer membrane protein with a deduced molecular mass of 93.4/89.5 (unprocessed/processed) kDa. The mature HmsH 788 aa polypeptide has a pI of 4.99. The hmsF gene has an open reading frame of 654 aa, encoding a 74.6/72.2 kDa OM protein with a pI of 5.16 when processed. A deduced 423 aa, 52 kDa protein with a pI of 10.83 is encoded by hmsR. HmsR has a basic, hydrophilic, and alpha-helical carboxyl terminus; 13 aa at the amino-terminal end and a 'KRKRAR' sequence at the carboxy-terminal end are essential for an Hms+ phenotype. The hmsS gene encodes a hypothetical 155 aa, 17.5 kDa protein with a pI of 6.68. Hms- Y. pestis strain M23-2 transformed with the cloned hmsHFRS locus developed an Hms(c) phenotype (Hms+ at 26-37 degrees C) due to mutations in genes outside the pgm locus.
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Affiliation(s)
- J W Lillard
- Department of Microbiology and Immunology, University of Kentucky, Lexington 40536-0084, USA
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25
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Bearden SW, Fetherston JD, Perry RD. Genetic organization of the yersiniabactin biosynthetic region and construction of avirulent mutants in Yersinia pestis. Infect Immun 1997; 65:1659-68. [PMID: 9125544 PMCID: PMC175193 DOI: 10.1128/iai.65.5.1659-1668.1997] [Citation(s) in RCA: 182] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
We have identified an approximately 22-kb region of the pgm locus of Yersinia pestis KIM6+ which encodes a number of iron-regulated proteins involved in the biosynthesis of the Y. pestis cognate siderophore, yersiniabactin (Ybt), and which is located immediately upstream of the pesticin/yersiniabactin receptor gene (psn). Sequence analysis and the construction of insertion and deletion mutants allowed us to determine the putative location of the irp1 gene and the positions of irp2, ybtT, and ybtE within the ybt operon. Mutations in the irp1, irp2, or ybtE gene yielded strains defective in siderophore production. Mutant strains were unable to grow on iron-deficient media at 37 degrees C but could be cross-fed by culture supernatants from yersiniabactin-producing strains of Y. pestis grown under iron-limiting conditions. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of whole-cell extracts from Ybt+ and Ybt- strains grown in iron-deficient media revealed that expression of ybt-encoded proteins is not only iron regulated but also influenced by the presence of the siderophore itself. Finally, Y. pestis strains with mutations in either the psn or irp2 gene were avirulent in mice when inoculated subcutaneously.
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Affiliation(s)
- S W Bearden
- Department of Microbiology and Immunology, University of Kentucky, Lexington 40536-0084, USA
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26
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Abstract
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.
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Affiliation(s)
- R D Perry
- Department of Microbiology and Immunology, University of Kentucky, Lexington 40536, USA.
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27
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Lucier TS, Fetherston JD, Brubaker RR, Perry RD. Iron uptake and iron-repressible polypeptides in Yersinia pestis. Infect Immun 1996; 64:3023-31. [PMID: 8757829 PMCID: PMC174183 DOI: 10.1128/iai.64.8.3023-3031.1996] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Pigmented (Pgm+) cells of Yersinia pestis are virulent, are sensitive to pesticin, adsorb exogenous hemin at 26 degrees C (Hms+), produce iron-repressible outer membrane proteins, and grow at 37 degrees C in iron-deficient media. These traits are lost upon spontaneous deletion of a chromosomal 102-kb pgm locus (Pgm-). Here we demonstrate that an Hms+ but pesticin-resistant (Pst(r)) mutant acquired a 5-bp deletion in the pesticin receptor gene (psn) encoding IrpB to IrpD. Growth and assimilation of iron by Pgm- and Hms+ Pst(r) mutants were markedly inhibited by ferrous chelators at 37 degrees C; inhibition by ferric and ferrous chelators was less effective at 26 degrees C. Iron-deficient growth at 26 degrees C induced iron-regulated outer membrane proteins of 34, 28.5, and 22.5 kDa and periplasmic polypeptides of 33.5 and 30 kDa. These findings provide a basis for understanding the psn-driven system of iron uptake, indicate the existence of at least one additional 26 degrees C-dependent iron assimilation system, and define over 30 iron-repressible proteins in Y. pestis.
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Affiliation(s)
- T S Lucier
- Department of Microbiology, Michigan State University, East Lansing 48824-1101, USA
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28
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Hinnebusch BJ, Perry RD, Schwan TG. Role of the Yersinia pestis hemin storage (hms) locus in the transmission of plague by fleas. Science 1996; 273:367-70. [PMID: 8662526 DOI: 10.1126/science.273.5273.367] [Citation(s) in RCA: 268] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Yersinia pestis, the cause of bubonic plague, is transmitted by the bites of infected fleas. Biological transmission of plague depends on blockage of the foregut of the flea by a mass of plague bacilli. Blockage was found to be dependent on the hemin storage (hms) locus. Yersinia pestis hms mutants established long-term infection of the flea's midgut but failed to colonize the proventriculus, the site in the foregut where blockage normally develops. Thus, the hms locus markedly alters the course of Y. pestis infection in its insect vector, leading to a change in blood-feeding behavior and to efficient transmission of plague.
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Affiliation(s)
- B J Hinnebusch
- Laboratory of Microbial Structure and Function, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT 59840, USA
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29
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Hornung JM, Jones HA, Perry RD. The hmu locus of Yersinia pestis is essential for utilization of free haemin and haem--protein complexes as iron sources. Mol Microbiol 1996; 20:725-39. [PMID: 9026634 DOI: 10.1111/j.1365-2958.1996.tb02512.x] [Citation(s) in RCA: 74] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Yersinia pestis strains utilize haem and several haem-protein complexes as sole sources of iron. In this study, the haemin uptake locus (hmu) of Y. pestis KIM6+ was selected from a genomic library by transduction into an Escherichia coli siderophore synthesis (entC) mutant. Recombinant plasmids containing a common 16 kb BamHI insert were isolated that allowed E. coli entC to use haemin as an iron source. An 8.6 kb region of this insert was found to be essential for haemin utilization and encoded at least five proteins with molecular masses of 79/77, 44, 37, 35, and 30/27.5 kDa. A 10.9 kb Clal fragment containing the hmu locus showed varying degrees of homology to genomic DNA from Yersinia pseudotuberculosis, Yersinia enterocolitica, and other genera of Enterobacteriaceae. An E. coli hemA aroB strain harbouring cloned hmu genes used haemin as both an iron and porphyrin source but only on iron-poor medium, suggesting that haemin uptake is tightly iron regulated. Additionally, haemoglobin and myoglobin were used as iron sources by an E. coli entC (pHMU2.2) strain. Deletion of the hmu locus from Y. pestis KIM6+ chromosome generated a mutant that grew poorly on iron-depleted medium containing free haemin as well as mammalian haem-protein complexes including haemoglobin, haemoglobin-haptoglobin, myoglobin, haem-haemopexin, and haem-albumin unless it was complemented with cloned hmu genes.
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Affiliation(s)
- J M Hornung
- Department of Microbiology and Immunology, University of Kentucky, Lexington 40536-0084, USA
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30
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Abstract
The yersiniae are a useful model for understanding how environmental modulation of gene expression allows pathogens to inhabit a wide range of niches. This review follows the enteropathogenic yersiniae, Yersinia enterocolitica and Yersinia pseudotuberculosis, and the agent of plague, Yersinia pestis, through their life cycles, describing how adaptive gene expression may promote successful pathogenesis.
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Affiliation(s)
- S C Straley
- Dept of Microbiology and Immunology, University of Kentucky, Lexington 40536-0084, USA
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31
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Fetherston JD, Lillard JW, Perry RD. Analysis of the pesticin receptor from Yersinia pestis: role in iron-deficient growth and possible regulation by its siderophore. J Bacteriol 1995; 177:1824-33. [PMID: 7896707 PMCID: PMC176812 DOI: 10.1128/jb.177.7.1824-1833.1995] [Citation(s) in RCA: 94] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
We have sequenced a region from the pgm locus of Yersinia pestis KIM6+ that confers sensitivity to the bacteriocin pesticin to certain strains of Escherichia coli and Y. pestis. The Y. pestis sequence is 98% identical to the pesticin receptor from Yersinia enterocolitica and is homologous to other TonB-dependent outer membrane proteins. Y. pestis strains with an in-frame deletion in the pesticin receptor gene (psn) were pesticin resistant and no longer expressed a group of iron-regulated outer membrane proteins, IrpB to IrpD. In addition, this strain as well as a Y. pestis strain with a mutation constructed in the gene (irp2) encoding the 190-kDa iron-regulated protein HMWP2 could not grow at 37 degrees C in a defined, iron-deficient medium. However, the irp2 mutant but not the psn mutant could be cross-fed by supernatants from various Yersinia cultures grown under iron-deficient conditions. An analysis of the proteins synthesized by the irp2 mutant suggests that HMWP2 may be indirectly required for maximal expression of the pesticin receptor. HMWP2 likely participates in synthesis of a siderophore which may induce expression of the receptor for pesticin and the siderophore.
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Affiliation(s)
- J D Fetherston
- Department of Microbiology and Immunology, University of Kentucky, Lexington 40536-0084
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32
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Abstract
A Yersinia pestis fur mutation was constructed by insertionally disrupting the fur open reading frame. Analysis of a Fur-regulated beta-galactosidase reporter gene revealed a loss of iron regulation as a result of the fur mutation. trans complementation with the cloned Y. pestis fur gene restored iron regulation. The expression of most iron-regulated proteins was also deregulated by this mutation; however, a number of iron-repressible and two iron-inducible polypeptides retained normal regulation. Mutations in fur or hmsH, a gene encoding an 86-kDa surface protein required for hemin storage, increased the sensitivity of Y. pestis cells to the bacteriocin pesticin. Interestingly, the Y. pestis fur mutant lost temperature control of hemin storage; however, expression of the HmsH polypeptide was not deregulated. When grown with excess iron, a Y. pestis fur mutant possessing the 102-kb pigmentation locus exhibited severe growth inhibition and a dramatic increase in the number of spontaneous nonpigmented chromosomal deletion mutants present at late log phase. These results suggest that the Fur protein of Y. pestis is an important global regulator and that a separate Fur-independent iron regulatory system may exist.
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Affiliation(s)
- T M Staggs
- Department of Microbiology and Immunology, University of Kentucky, Lexington 40536-0084
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33
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Fetherston JD, Perry RD. The pigmentation locus of Yersinia pestis KIM6+ is flanked by an insertion sequence and includes the structural genes for pesticin sensitivity and HMWP2. Mol Microbiol 1994; 13:697-708. [PMID: 7997181 DOI: 10.1111/j.1365-2958.1994.tb00463.x] [Citation(s) in RCA: 97] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The pigmentation (Pgm+) phenotype of Yersinia pestis includes a number of different characteristics which appear to be associated with a 102 kb segment of chromosomal DNA known as the pgm locus. In Y. pestis KIM6+, the pgm locus is flanked by direct copies of a repeated element that probably plays a role in the spontaneous deletion of this region. We have sequenced the ends of these elements and shown that they have features in common with bacterial insertion sequences. In addition we show that a clone, pSDR498, from the pgm locus of KIM6+ restores pesticin sensitivity and the iron-regulated expression of three polypeptides, 240 kDa, 190 kDa, and 68 kDa in size, to Pgm- cells. In vitro transcription/translation assays and Escherichia coli minicells were used to analyse the products encoded by various subclones of pSDR498. Pesticin sensitivity mapped to a 5.9 kb fragment that encodes a 68 kDa protein derived from a 72 kDa precursor. Synthesis of the 190 kDa protein was restored by a 19.2 kb clone, indicating that the structural gene for this protein also resides within the pgm locus of Y. pestis KIM6+. Finally, a survey of our Pgm- strains indicates that 97% have also deleted the sequences encoding the 190 kDa protein and pesticin sensitivity.
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Affiliation(s)
- J D Fetherston
- Department of Microbiology and Immunology, University of Kentucky, Lexington 40536-0084
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34
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Rakin A, Saken E, Harmsen D, Heesemann J. The pesticin receptor of Yersinia enterocolitica: a novel virulence factor with dual function. Mol Microbiol 1994; 13:253-63. [PMID: 7984105 DOI: 10.1111/j.1365-2958.1994.tb00420.x] [Citation(s) in RCA: 125] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The iron-repressible outer membrane protein FyuA of Yersinia enterocolitica operates as a receptor with dual function: (i) as a receptor for the Y. pestis bacteriocin pesticin, and (ii) as a receptor for yersiniabactin, a siderophore that is produced by mouse-virulent Y. enterocolitica strains of biogroup IB. Cloning of the FyuA-encoding gene was achieved by mobilization of a genomic cosmid library of the pesticin-sensitive and mouse-virulent Y. enterocolitica O:8 strain WA into the pesticin-resistant WA fyuA mutant and subsequent in vivo selection of transconjugants for the ability to survive and multiply in mice (phenotype mouse virulence). The reisolated transconjugants which survived in mice for 3 d harboured a unique cosmid and phenotypically were pesticin sensitive. From this cosmid a 2650 bp SalI-PstI fragment conferring pesticin sensitivity was subcloned. Sequencing of this DNA fragment revealed a single open reading frame of 2022 bp, which encodes a deduced polypeptide of 673 amino acids with a predicted molecular mass of 73,677 Da. Cleavage of a putative signal sequence composed of 22 amino acids should lead to a mature protein of 651 amino acids with a molecular mass of 71,368 Da. The open reading frame is preceded by a sequence which shares homology with the postulated consensus Fur iron-repressor protein-binding site. FyuA shows homology to other iron-regulated TonB-dependent outer membrane proteins with receptor functions (e.g. BtuB, CirA, FepA, IutA, FhuA, FoxA, FcuA). On the basis of multiple alignment of amino acid sequences of FyuA and other TonB-dependent receptors, a phylogenetic tree was constructed, demonstrating that FyuA probably belongs to the citrate subfamily or represents a new subfamily of TonB-dependent receptors. Moreover, by complementation of the WA fyuA mutant by the cloned fyuA gene, yersiniabactin uptake and mouse virulence were restored. These studies demonstrate that the cloned pesticin/yersiniabactin receptor FyuA of Y. enterocolitica has the typical features of iron-regulated TonB-dependent outer membrane receptors for siderophores and bacteriocins and is required for mouse virulence.
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Affiliation(s)
- A Rakin
- Institut für Hygiene und Mikrobiologie, Universität Würzburg, Germany
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35
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Abstract
Pathogenic Yersinia express a complex array of iron-regulated functions and possess mechanisms for inorganic iron and hemin acquisition. These include a unique temperature-regulated hemin storage system, high-affinity transport processes for hemin and inorganic iron, and an iron-responsive regulatory system controlling gene expression. The genetic organization of these systems illuminates several aspects of iron metabolism in the yersiniae.
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Affiliation(s)
- R D Perry
- Dept of Microbiology and Immunology, University of Kentucky, Lexington 40536-0084
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Heesemann J, Hantke K, Vocke T, Saken E, Rakin A, Stojiljkovic I, Berner R. Virulence of Yersinia enterocolitica is closely associated with siderophore production, expression of an iron-repressible outer membrane polypeptide of 65,000 Da and pesticin sensitivity. Mol Microbiol 1993; 8:397-408. [PMID: 8316088 DOI: 10.1111/j.1365-2958.1993.tb01583.x] [Citation(s) in RCA: 133] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Iron-repressible outer membrane proteins (Irp) and siderophore production of Yersinia enterocolitica, serotype 08, were subjected to analysis. Here four Irps of apparent molecular weights of 62,000, 65,000, 74,000 and 75,000 could be identified which were expressed constitutively by a fur mutant. Production of a novel catechol-containing siderophore (denoted yersiniabactin) was detected by siderophore-indicator agar (chrome azurol S) and feeding experiments. Growth support by yersiniabactin under iron-restricted conditions was TonB- and Irp65-dependent and correlated with pesticin-sensitivity of Yersinia enterocolitica and Escherichia coli O. From these results we conclude that Irp65 of Y. enterocolitica functions as yersiniabactin receptor (FyuA) and as pesticin receptor. By immunoblotting using rabbit antibodies against Irp65 and chrome azurol S-agar, we were able to demonstrate that all tested mouse-lethal Y. enterocolitica and Yersinia pseudotuberculosis strains of different serotypes express siderophores and Irp65. Moreover, the anti-Irp65 rabbit serum did not cross-react with the known iron-repressible high-molecular-weight proteins (HMWPs). Evidently, the mouse lethality trait in enteropathogenic Yersinia spp. is closely associated with a novel iron-uptake system, comprising the production of a siderophore and a siderophore receptor of apparent molecular mass 65,000 Da.
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Affiliation(s)
- J Heesemann
- Institut für Hygiene und Mikrobiologie der Universität, Würzburg, Germany
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Perry RD, Lucier TS, Sikkema DJ, Brubaker RR. Storage reservoirs of hemin and inorganic iron in Yersinia pestis. Infect Immun 1993; 61:32-9. [PMID: 8418054 PMCID: PMC302684 DOI: 10.1128/iai.61.1.32-39.1993] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
It is established that a high-frequency chromosomal deletion of ca. 100 kb accounts for the loss of properties making up the pigmented phenotype (Pgm+) of wild-type Yersinia pestis. These determinants are known to include virulence by peripheral routes of injection, sensitivity to the bacteriocin pesticin, adsorption of exogenous hemin or Congo red at 26 degrees C, and growth in iron-sequestered medium at 37 degrees C. We have now identified the outer membrane as the primary site of exogenous hemin storage in Pgm+ cells grown at 26 degrees C. Significant outer membrane storage of hemin did not occur in Pgm- mutants or in Pgm+ cells cultivated at 37 degrees C. However, both Pgm+ and Pgm- organisms grown at 37 degrees C contained a periplasmic reservoir of hemin, which may be associated with a temperature-dependent ca. 70-kDa peptide recently equated with antigen 5. At 37 degrees C, Pgm+ and Pgm- yersiniae also utilized a cytoplasmic ca. 19-kDa bacterioferritin-like peptide for deposition of inorganic iron. Incorporation of [55Fe]hemin into pools at 37 degrees C was not significantly inhibited by competition with excess unlabeled Fe3+. However, excess unlabeled hemin modestly competed with incorporation of label from 55FeCl3. This relative independence of storage pools observed at 37 degrees C is consistent with physiological linkage to in vivo acquisition and transport of Fe3+ from ferritin and of hemin from hemoglobin, myoglobin, or hemopexin.
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Affiliation(s)
- R D Perry
- Department of Microbiology and Immunology, University of Kentucky, Lexington 40536-0084
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