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Luo Y, Kong Q, Yang J, Mitra A, Golden G, Wanda SY, Roland KL, Jensen RV, Ernst PB, Curtiss R. Comparative genome analysis of the high pathogenicity Salmonella Typhimurium strain UK-1. PLoS One 2012; 7:e40645. [PMID: 22792393 PMCID: PMC3391293 DOI: 10.1371/journal.pone.0040645] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2011] [Accepted: 06/13/2012] [Indexed: 12/26/2022] Open
Abstract
Salmonella enterica serovar Typhimurium, a gram-negative facultative rod-shaped bacterium causing salmonellosis and foodborne disease, is one of the most common isolated Salmonella serovars in both developed and developing nations. Several S. Typhimurium genomes have been completed and many more genome-sequencing projects are underway. Comparative genome analysis of the multiple strains leads to a better understanding of the evolution of S. Typhimurium and its pathogenesis. S. Typhimurium strain UK-1 (belongs to phage type 1) is highly virulent when orally administered to mice and chickens and efficiently colonizes lymphoid tissues of these species. These characteristics make this strain a good choice for use in vaccine development. In fact, UK-1 has been used as the parent strain for a number of nonrecombinant and recombinant vaccine strains, including several commercial vaccines for poultry. In this study, we conducted a thorough comparative genome analysis of the UK-1 strain with other S. Typhimurium strains and examined the phenotypic impact of several genomic differences. Whole genomic comparison highlights an extremely close relationship between the UK-1 strain and other S. Typhimurium strains; however, many interesting genetic and genomic variations specific to UK-1 were explored. In particular, the deletion of a UK-1-specific gene that is highly similar to the gene encoding the T3SS effector protein NleC exhibited a significant decrease in oral virulence in BALB/c mice. The complete genetic complements in UK-1, especially those elements that contribute to virulence or aid in determining the diversity within bacterial species, provide key information in evaluating the functional characterization of important genetic determinants and for development of vaccines.
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Affiliation(s)
- Yingqin Luo
- Center for Infectious Diseases and Vaccinology, The Biodesign Institute, Arizona State University, Tempe, Arizona, United States of America
- Center for Evolutionary Medicine and Informatics, The Biodesign Institute, Arizona State University, Tempe, Arizona, United States of America
| | - Qingke Kong
- Center for Infectious Diseases and Vaccinology, The Biodesign Institute, Arizona State University, Tempe, Arizona, United States of America
| | - Jiseon Yang
- Center for Infectious Diseases and Vaccinology, The Biodesign Institute, Arizona State University, Tempe, Arizona, United States of America
| | - Arindam Mitra
- Center for Infectious Diseases and Vaccinology, The Biodesign Institute, Arizona State University, Tempe, Arizona, United States of America
| | - Greg Golden
- Center for Infectious Diseases and Vaccinology, The Biodesign Institute, Arizona State University, Tempe, Arizona, United States of America
| | - Soo-Young Wanda
- Center for Infectious Diseases and Vaccinology, The Biodesign Institute, Arizona State University, Tempe, Arizona, United States of America
| | - Kenneth L. Roland
- Center for Infectious Diseases and Vaccinology, The Biodesign Institute, Arizona State University, Tempe, Arizona, United States of America
| | - Roderick V. Jensen
- Department of Biological Sciences, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, United States of America
| | - Peter B. Ernst
- Department of Medicine, Division of Gastroenterology and Hepatology, University of Virginia, Charlottesville, Virginia, United States of America
| | - Roy Curtiss
- Center for Infectious Diseases and Vaccinology, The Biodesign Institute, Arizona State University, Tempe, Arizona, United States of America
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52
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Du XJ, Wang F, Lu X, Rasco BA, Wang S. Biochemical and genetic characteristics of Cronobacter sakazakii biofilm formation. Res Microbiol 2012; 163:448-56. [DOI: 10.1016/j.resmic.2012.06.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2012] [Accepted: 06/18/2012] [Indexed: 01/03/2023]
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Knirel Y, Anisimov A. Lipopolysaccharide of Yersinia pestis, the Cause of Plague: Structure, Genetics, Biological Properties. Acta Naturae 2012; 4:46-58. [PMID: 23150803 PMCID: PMC3492934] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The present review summarizes data pertaining to the composition and structure of the carbohydrate moiety (core oligosaccharide) and lipid component (lipid A) of the various forms of lipopolysaccharide (LPS), one of the major pathogenicity factors ofYersinia pestis, the cause of plague. The review addresses the functions and the biological significance of genes for the biosynthesis of LPS, as well as the biological properties of LPS in strains from various intraspecies groups ofY. pestis and their mutants, including the contribution of LPS to the resistance of bacteria to factors of the innate immunity of both insect-vectors and mammal-hosts. Special attention is paid to temperature-dependent variations in the LPS structure, their genetic control and roles in the pathogenesis of plague. The evolutionary aspect is considered based on a comparison of the structure and genetics of the LPS ofY. pestis and other enteric bacteria, including otherYersinia species. The prospects of development of live plague vaccines created on the basis ofY. pestis strains with the genetically modified LPS are discussed.
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Affiliation(s)
- Y.A. Knirel
- Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninsky
prospect, 47, Moscow, Russia, 119991
| | - A.P. Anisimov
- State Research Center for Applied Microbiology and Biotechnology, Obolensk,
Moscow Region, Russia, 142279
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54
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Wang X, Yang X, Yang C, Wu Z, Xu H, Shen Y. Crystal structure of outer membrane protein NMB0315 from Neisseria meningitidis. PLoS One 2011; 6:e26845. [PMID: 22046377 PMCID: PMC3202590 DOI: 10.1371/journal.pone.0026845] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2011] [Accepted: 10/05/2011] [Indexed: 01/01/2023] Open
Abstract
NMB0315 is an outer membrane protein of Neisseria meningitidis serogroup B (NMB) and a potential candidate for a broad-spectrum vaccine against meningococcal disease. The crystal structure of NMB0315 was solved by single-wavelength anomalous dispersion (SAD) at a resolution of 2.4 Å and revealed to be a lysostaphin-type peptidase of the M23 metallopeptidase family. The overall structure consists of three well-separated domains and has no similarity to any previously published structure. However, only the topology of the carboxyl-terminal domain is highly conserved among members of this family, and this domain is a zinc-dependent catalytic unit. The amino-terminal domain of the structure blocks the substrate binding pocket in the carboxyl-terminal domain, indicating that the wild-type full-length protein is in an inactive conformational state. Our studies improve the understanding of the catalytic mechanism of M23 metallopeptidases.
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Affiliation(s)
- Xiangyu Wang
- State Key Laboratory of Medicinal Chemical Biology, Nankai University, Tianjin, China
- College of Life Sciences, Nankai University, Tianjin, China
| | - Xue Yang
- State Key Laboratory of Medicinal Chemical Biology, Nankai University, Tianjin, China
- College of Life Sciences, Nankai University, Tianjin, China
| | - Chunting Yang
- Laboratory of Virology, National Vaccine and Serum Institute, Beijing, China
| | - Zhenhua Wu
- Laboratory of Virology, National Vaccine and Serum Institute, Beijing, China
| | - Honglin Xu
- Laboratory of Virology, National Vaccine and Serum Institute, Beijing, China
- * E-mail: (HX); (YS)
| | - Yuequan Shen
- State Key Laboratory of Medicinal Chemical Biology, Nankai University, Tianjin, China
- College of Life Sciences, Nankai University, Tianjin, China
- * E-mail: (HX); (YS)
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55
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Filippov AA, Sergueev KV, He Y, Huang XZ, Gnade BT, Mueller AJ, Fernandez-Prada CM, Nikolich MP. Bacteriophage-resistant mutants in Yersinia pestis: identification of phage receptors and attenuation for mice. PLoS One 2011; 6:e25486. [PMID: 21980477 PMCID: PMC3182234 DOI: 10.1371/journal.pone.0025486] [Citation(s) in RCA: 126] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2011] [Accepted: 09/06/2011] [Indexed: 01/21/2023] Open
Abstract
Background Bacteriophages specific for Yersinia pestis are routinely used for plague diagnostics and could be an alternative to antibiotics in case of drug-resistant plague. A major concern of bacteriophage therapy is the emergence of phage-resistant mutants. The use of phage cocktails can overcome this problem but only if the phages exploit different receptors. Some phage-resistant mutants lose virulence and therefore should not complicate bacteriophage therapy. Methodology/Principal Findings The purpose of this work was to identify Y. pestis phage receptors using site-directed mutagenesis and trans-complementation and to determine potential attenuation of phage-resistant mutants for mice. Six receptors for eight phages were found in different parts of the lipopolysaccharide (LPS) inner and outer core. The receptor for R phage was localized beyond the LPS core. Most spontaneous and defined phage-resistant mutants of Y. pestis were attenuated, showing increase in LD50 and time to death. The loss of different LPS core biosynthesis enzymes resulted in the reduction of Y. pestis virulence and there was a correlation between the degree of core truncation and the impact on virulence. The yrbH and waaA mutants completely lost their virulence. Conclusions/Significance We identified Y. pestis receptors for eight bacteriophages. Nine phages together use at least seven different Y. pestis receptors that makes some of them promising for formulation of plague therapeutic cocktails. Most phage-resistant Y. pestis mutants become attenuated and thus should not pose a serious problem for bacteriophage therapy of plague. LPS is a critical virulence factor of Y. pestis.
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Affiliation(s)
- Andrey A Filippov
- Division of Bacterial and Rickettsial Diseases, Department of Emerging Bacterial Infections, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America.
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Sun W, Roland KL, Curtiss R. Developing live vaccines against plague. J Infect Dev Ctries 2011; 5:614-27. [PMID: 21918302 PMCID: PMC3932668 DOI: 10.3855/jidc.2030] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2011] [Revised: 05/20/2011] [Accepted: 05/22/2011] [Indexed: 12/13/2022] Open
Abstract
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 plagu.
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Affiliation(s)
- Wei Sun
- Center for Infectious Disease and Vaccinology, The Biodesign Institute and School of Life Sciences, Arizona State University, Tempe, AZ 85287-5401 , USA
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57
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Levy Y, Flashner Y, Tidhar A, Zauberman A, Aftalion M, Lazar S, Gur D, Shafferman A, Mamroud E. T cells play an essential role in anti-F1 mediated rapid protection against bubonic plague. Vaccine 2011; 29:6866-73. [PMID: 21803090 DOI: 10.1016/j.vaccine.2011.07.059] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2011] [Revised: 07/14/2011] [Accepted: 07/16/2011] [Indexed: 10/17/2022]
Abstract
Plague, which is initiated by Yersinia pestis infection, is a fatal disease that progresses rapidly and leads to high mortality rates if not treated. Antibiotics are an effective plague therapy, but antibiotic-resistant Y. pestis strains have been reported and therefore alternative countermeasures are needed. In the present study, we assessed the potential of an F1 plus LcrV-based vaccine to provide protection shortly pre- or post-exposure to a lethal Y. pestis infection. Mice vaccinated up to one day before or even several hours after subcutaneous challenge were effectively protected. Mice immunized one or three days pre-challenge were protected even though their anti-F1 and anti-LcrV titers were below detection levels at the day of challenge. Moreover, using B-cell deficient μMT mice, we found that rapidly induced protective immunity requires the integrity of the humoral immune system. Analysis of the individual contributions of vaccine components to protection revealed that rF1 is responsible for the observed rapid antibody-mediated immunity. Applying anti-F1 passive therapy in the mouse model of bubonic plague demonstrated that anti-F1 F(ab')(2) can delay mortality, but it cannot provide long-lasting protection, as do intact anti-F1 molecules. Fc-dependent immune components, such as the complement system and (to a lesser extent) neutrophils, were found to contribute to mouse survival. Interestingly, T cells but not B cells were found to be essential for the recovery of infected animals following passive anti-F1 mediated therapy. These data extend our understanding of the immune mechanisms required for the development of a rapid and effective post-exposure therapy against plague.
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Affiliation(s)
- Yinon Levy
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research, Ness-Ziona, Israel
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58
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Rosenzweig JA, Jejelowo O, Sha J, Erova TE, Brackman SM, Kirtley ML, van Lier CJ, Chopra AK. Progress on plague vaccine development. Appl Microbiol Biotechnol 2011; 91:265-86. [PMID: 21670978 DOI: 10.1007/s00253-011-3380-6] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2011] [Revised: 05/11/2011] [Accepted: 05/11/2011] [Indexed: 12/15/2022]
Abstract
Yersinia pestis (YP), the gram-negative plague bacterium, has shaped human history unlike any other pathogen known to mankind. YP (transmitted by the bite of an infected flea) diverged only recently from the related enteric pathogen Yersinia pseudotuberculosis but causes radically different diseases. Three forms of plague exist in humans: bubonic (swollen lymph nodes or bubos), septicemic (spread of YP through the lymphatics or bloodstream from the bubos to other organs), and contagious, pneumonic plague which can be communicated via YP-charged respiratory droplets resulting in person-person transmission and rapid death if left untreated (50-90% mortality). Despite the potential threat of weaponized YP being employed in bioterrorism and YP infections remaining prevalent in endemic regions of the world where rodent populations are high (including the four corner regions of the USA), an efficacious vaccine that confers immunoprotection has yet to be developed. This review article will describe the current vaccine candidates being evaluated in various model systems and provide an overall summary on the progress of this important endeavor.
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Affiliation(s)
- Jason A Rosenzweig
- Department of Biology, Center for Bionanotechnology and Environmental Research (CBER), Texas Southern University, 3100 Cleburne Street, Houston, TX 77004, USA.
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59
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Lau SK, Fan RY, Ho TC, Wong GK, Tsang AK, Teng JL, Chen W, Watt RM, Curreem SO, Tse H, Yuen KY, Woo PC. Environmental adaptability and stress tolerance of Laribacter hongkongensis: a genome-wide analysis. Cell Biosci 2011; 1:22. [PMID: 21711489 PMCID: PMC3135505 DOI: 10.1186/2045-3701-1-22] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2011] [Accepted: 06/14/2011] [Indexed: 12/31/2022] Open
Abstract
Background Laribacter hongkongensis is associated with community-acquired gastroenteritis and traveler's diarrhea and it can reside in human, fish, frogs and water. In this study, we performed an in-depth annotation of the genes in its genome related to adaptation to the various environmental niches. Results L. hongkongensis possessed genes for DNA repair and recombination, basal transcription, alternative σ-factors and 109 putative transcription factors, allowing DNA repair and global changes in gene expression in response to different environmental stresses. For acid stress, it possessed a urease gene cassette and two arc gene clusters. For alkaline stress, it possessed six CDSs for transporters of the monovalent cation/proton antiporter-2 and NhaC Na+:H+ antiporter families. For heavy metals acquisition and tolerance, it possessed CDSs for iron and nickel transport and efflux pumps for other metals. For temperature stress, it possessed genes related to chaperones and chaperonins, heat shock proteins and cold shock proteins. For osmotic stress, 25 CDSs were observed, mostly related to regulators for potassium ion, proline and glutamate transport. For oxidative and UV light stress, genes for oxidant-resistant dehydratase, superoxide scavenging, hydrogen peroxide scavenging, exclusion and export of redox-cycling antibiotics, redox balancing, DNA repair, reduction of disulfide bonds, limitation of iron availability and reduction of iron-sulfur clusters are present. For starvation, it possessed phosphorus and, despite being asaccharolytic, carbon starvation-related CDSs. Conclusions The L. hongkongensis genome possessed a high variety of genes for adaptation to acid, alkaline, temperature, osmotic, oxidative, UV light and starvation stresses and acquisition of and tolerance to heavy metals.
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Affiliation(s)
- Susanna Kp Lau
- State Key Laboratory of Emerging Infectious Diseases, Hong Kong.,Research Centre of Infection and Immunology, The University of Hong Kong, Hong Kong.,Carol Yu Centre of Infection, The University of Hong Kong, Hong Kong.,Department of Microbiology, The University of Hong Kong, Hong Kong
| | - Rachel Yy Fan
- Department of Microbiology, The University of Hong Kong, Hong Kong
| | - Tom Cc Ho
- Department of Microbiology, The University of Hong Kong, Hong Kong
| | - Gilman Km Wong
- Department of Microbiology, The University of Hong Kong, Hong Kong
| | - Alan Kl Tsang
- Department of Microbiology, The University of Hong Kong, Hong Kong
| | - Jade Ll Teng
- Department of Microbiology, The University of Hong Kong, Hong Kong
| | - Wenyang Chen
- Faculty of Dentistry, The University of Hong Kong, Hong Kong
| | - Rory M Watt
- Faculty of Dentistry, The University of Hong Kong, Hong Kong
| | | | - Herman Tse
- State Key Laboratory of Emerging Infectious Diseases, Hong Kong.,Research Centre of Infection and Immunology, The University of Hong Kong, Hong Kong.,Carol Yu Centre of Infection, The University of Hong Kong, Hong Kong.,Department of Microbiology, The University of Hong Kong, Hong Kong
| | - Kwok-Yung Yuen
- State Key Laboratory of Emerging Infectious Diseases, Hong Kong.,Research Centre of Infection and Immunology, The University of Hong Kong, Hong Kong.,Carol Yu Centre of Infection, The University of Hong Kong, Hong Kong.,Department of Microbiology, The University of Hong Kong, Hong Kong
| | - Patrick Cy Woo
- State Key Laboratory of Emerging Infectious Diseases, Hong Kong.,Research Centre of Infection and Immunology, The University of Hong Kong, Hong Kong.,Carol Yu Centre of Infection, The University of Hong Kong, Hong Kong.,Department of Microbiology, The University of Hong Kong, Hong Kong
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A novel zinc binding system, ZevAB, is critical for survival of nontypeable Haemophilus influenzae in a murine lung infection model. Infect Immun 2011; 79:3366-76. [PMID: 21576338 DOI: 10.1128/iai.05135-11] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Nontypeable Haemophilus influenzae (NTHI) is a Gram-negative bacterial pathogen that causes upper and lower respiratory infections. Factors required for pulmonary infection by NTHI are not well understood. Previously, using high-throughput insertion tracking by deep sequencing (HITS), putative lung colonization factors were identified. Also, previous research indicates that secreted disulfide-dependent factors are important for virulence of H. influenzae. In the present study, HITS data were compared with an informatics-based list of putative substrates of the periplasmic oxidoreductase DsbA to find and characterize secreted virulence factors. This analysis resulted in identification of the "zinc binding essential for virulence" (zev) locus consisting of zevA (HI1249) and zevB (HI1248). NTHI mutants of zevA and zevB grew normally in rich medium but were defective for colonization in a mouse lung model. Mutants also exhibited severe growth defects in medium containing EDTA and were rescued by supplementation with zinc. Additionally, purified recombinant ZevA was found to bind to zinc with high affinity. Together, these data demonstrate that zevAB is a novel virulence factor important for zinc utilization of H. influenzae under conditions where zinc is limiting. Furthermore, evidence presented here suggests that zinc limitation is likely an important mechanism for host defense against pathogens during lung infection.
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61
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Echenique-Rivera H, Muzzi A, Del Tordello E, Seib KL, Francois P, Rappuoli R, Pizza M, Serruto D. Transcriptome analysis of Neisseria meningitidis in human whole blood and mutagenesis studies identify virulence factors involved in blood survival. PLoS Pathog 2011; 7:e1002027. [PMID: 21589640 PMCID: PMC3088726 DOI: 10.1371/journal.ppat.1002027] [Citation(s) in RCA: 117] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2010] [Accepted: 02/26/2011] [Indexed: 12/14/2022] Open
Abstract
During infection Neisseria meningitidis (Nm) encounters multiple environments within the host, which makes rapid adaptation a crucial factor for meningococcal survival. Despite the importance of invasion into the bloodstream in the meningococcal disease process, little is known about how Nm adapts to permit survival and growth in blood. To address this, we performed a time-course transcriptome analysis using an ex vivo model of human whole blood infection. We observed that Nm alters the expression of ≈30% of ORFs of the genome and major dynamic changes were observed in the expression of transcriptional regulators, transport and binding proteins, energy metabolism, and surface-exposed virulence factors. In particular, we found that the gene encoding the regulator Fur, as well as all genes encoding iron uptake systems, were significantly up-regulated. Analysis of regulated genes encoding for surface-exposed proteins involved in Nm pathogenesis allowed us to better understand mechanisms used to circumvent host defenses. During blood infection, Nm activates genes encoding for the factor H binding proteins, fHbp and NspA, genes encoding for detoxifying enzymes such as SodC, Kat and AniA, as well as several less characterized surface-exposed proteins that might have a role in blood survival. Through mutagenesis studies of a subset of up-regulated genes we were able to identify new proteins important for survival in human blood and also to identify additional roles of previously known virulence factors in aiding survival in blood. Nm mutant strains lacking the genes encoding the hypothetical protein NMB1483 and the surface-exposed proteins NalP, Mip and NspA, the Fur regulator, the transferrin binding protein TbpB, and the L-lactate permease LctP were sensitive to killing by human blood. This increased knowledge of how Nm responds to adaptation in blood could also be helpful to develop diagnostic and therapeutic strategies to control the devastating disease cause by this microorganism.
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MESH Headings
- Adaptation, Physiological
- Adult
- Antigens, Bacterial/genetics
- Bacteremia/blood
- Bacteremia/microbiology
- Bacterial Proteins/genetics
- Cluster Analysis
- Down-Regulation/genetics
- Female
- Gene Expression Regulation, Bacterial/genetics
- Genes, Bacterial/genetics
- Genome, Bacterial/genetics
- Host-Pathogen Interactions/genetics
- Humans
- Male
- Meningococcal Infections/blood
- Meningococcal Infections/microbiology
- Models, Biological
- Neisseria meningitidis, Serogroup B/genetics
- Neisseria meningitidis, Serogroup B/growth & development
- Neisseria meningitidis, Serogroup B/pathogenicity
- Neisseria meningitidis, Serogroup B/physiology
- RNA, Bacterial/genetics
- Sequence Deletion
- Transcriptome
- Up-Regulation/genetics
- Virulence Factors/genetics
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Affiliation(s)
| | | | | | | | - Patrice Francois
- Genomic Research Laboratory, University of
Geneva Hospitals (HUG), Geneva, Switzerland
| | | | | | - Davide Serruto
- Novartis Vaccines and Diagnostics, Siena,
Italy
- * E-mail:
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62
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Abstract
Bacterial lipoproteins are a set of membrane proteins with many different functions. Due to this broad-ranging functionality, these proteins have a considerable significance in many phenomena, from cellular physiology through cell division and virulence. Here we give a general overview of lipoprotein biogenesis and highlight examples of the roles of lipoproteins in bacterial disease caused by a selection of medically relevant Gram-negative and Gram-positive pathogens: Mycobacterium tuberculosis, Streptococcus pneumoniae, Borrelia burgdorferi, and Neisseria meningitidis. Lipoproteins have been shown to play key roles in adhesion to host cells, modulation of inflammatory processes, and translocation of virulence factors into host cells. As such, a number of lipoproteins have been shown to be potential vaccines. This review provides a summary of some of the reported roles of lipoproteins and of how this knowledge has been exploited in some cases for the generation of novel countermeasures to bacterial diseases.
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63
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Biosafety level 2 model of pneumonic plague and protection studies with F1 and Psa. Infect Immun 2010; 78:3443-53. [PMID: 20498260 DOI: 10.1128/iai.00382-10] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Attenuated Yersinia pestis pgm strains, such as KIM5, lack the siderophore yersiniabactin. Strain KIM5 does not induce significant pneumonia when delivered intranasally. In this study, mice were found to develop pneumonia after intranasal challenge with strain KIM5 when they were injected intraperitoneally with iron dextran, though not with iron sulfate. KIM5-infected mice treated daily with 4 mg iron dextran died in 3 days with severe pneumonia. Pneumonia was less severe if 4 mg iron dextran was administered only once before infection. The best-studied experimental vaccine against plague currently consists of the Yersinia pestis capsular antigen F1 and the type 3 secreted protein LcrV. The F1 antigen was shown to be protective against KIM5 infections in mice administered iron dextran doses leading to light or severe pneumonia, supporting the use of an iron dextran-treated model of pneumonic plague. Since F1 has been reported to be incompletely protective in some primates, and bacterial isolates lacking F1 are still virulent, there has been considerable interest in identifying additional protective subunit immunogens. Here we showed that the highly conserved Psa fimbriae of Y. pestis (also called pH 6 antigen) are expressed in murine organs after infection through the respiratory tract. Studies with iron dextran-treated mice showed that vaccination with the Psa fimbrial protein together with an adjuvant afforded incomplete but significant protection in the mouse model described. Therefore, further investigations to fully characterize the protective properties of the Psa fimbriae are warranted.
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