1
|
Activation of the NLRP1b inflammasome independently of ASC-mediated caspase-1 autoproteolysis and speck formation. Nat Commun 2015; 5:3209. [PMID: 24492532 PMCID: PMC3926011 DOI: 10.1038/ncomms4209] [Citation(s) in RCA: 169] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2013] [Accepted: 01/07/2014] [Indexed: 01/03/2023] Open
Abstract
Despite its clinical importance in infection and autoimmunity, the activation mechanisms of the NLRP1b inflammasome remain enigmatic. Here we show that deletion of the inflammasome adaptor ASC in BALB/c mice and in C57BL/6 macrophages expressing a functional NLRP1b prevents anthrax lethal toxin (LeTx)-induced caspase-1 autoproteolysis and speck formation. However, ASC−/− macrophages undergo normal LeTx-induced pyroptosis and secrete significant amounts of interleukin (IL)-1β. In contrast, ASC is critical for caspase-1 autoproteolysis and IL-1β secretion by the NLRC4, NLRP3 and AIM2 inflammasomes. Notably, LeTx-induced inflammasome activation is associated with caspase-1 ubiquitination, which is unaffected in ASC-deficient cells. In vivo, ASC-deficient mice challenged with LeTx produce significant levels of IL-1β, IL-18 and HMGB1 in circulation, although caspase-1 autoproteolysis is abolished. As a result, ASC−/− mice are sensitive to rapid LeTx-induced lethality. Together, these results demonstrate that ASC-driven caspase-1 autoprocessing and speck formation are dispensable for the activation of caspase-1 and the NLRP1b inflammasome. The NLRP1b inflammasome activation may lead to pyroptosis and secretion of the inflammatory cytokines IL-1ß and IL-18 but the mechanisms behind these processes are not fully understood. Here, the authors show that they can occur independently of the inflammasome adaptor ASC and without caspase-1 autoprocessing.
Collapse
|
2
|
Carlson PE, Bourgis AET, Hagan AK, Hanna PC. Global gene expression by Bacillus anthracis during growth in mammalian blood. Pathog Dis 2015; 73:ftv061. [PMID: 26316554 DOI: 10.1093/femspd/ftv061] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/07/2015] [Indexed: 01/03/2023] Open
Abstract
During the late stages of systemic anthrax, Bacillus anthracis grows rapidly in the host bloodstream. To identify potential genes necessary for this observed rapid growth, we defined the transcriptional profile of B. anthracis during in vitro growth in bovine blood. Genome-wide transcriptome analysis indicated that B. anthracis undergoes significant changes in its transcriptome profile during growth in blood, including the differential regulation of genes associated both with metabolism and known virulence factors. Collectively, these data provide a framework for future studies identifying specific B. anthracis factors required for growth in the mammalian bloodstream.
Collapse
Affiliation(s)
- Paul E Carlson
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI 48104, USA
| | - Alexandra E T Bourgis
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI 48104, USA
| | - Ada K Hagan
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI 48104, USA
| | - Philip C Hanna
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI 48104, USA
| |
Collapse
|
3
|
Dixon SD, Janes BK, Bourgis A, Carlson PE, Hanna PC. Multiple ABC transporters are involved in the acquisition of petrobactin in Bacillus anthracis. Mol Microbiol 2012; 84:370-82. [PMID: 22429808 DOI: 10.1111/j.1365-2958.2012.08028.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
In Bacillus anthracis the siderophore petrobactin is vital for iron acquisition and virulence. The petrobactin-binding receptor FpuA is required for these processes. Here additional components of petrobactin reacquisition are described. To identify these proteins, mutants of candidate permease and ATPase genes were generated allowing for characterization of multiple petrobactin ATP-binding cassette (ABC)-import systems. Either of two distinct permeases, FpuB or FatCD, is required for iron acquisition and play redundant roles in petrobactin transport. A mutant strain lacking both permeases, ΔfpuBΔfatCD, was incapable of using petrobactin as an iron source and exhibited attenuated virulence in a murine model of inhalational anthrax infection. ATPase mutants were generated in either of the permease mutant backgrounds to identify the ATPase(s) interacting with each individual permease channel. Mutants lacking the FpuB permease and FatE ATPase (ΔfpuBΔfatE) and a mutant lacking the distinct ATPases FpuC and FpuD generated in the ΔfatCD background (ΔfatCDΔfpuCΔfpuD) displayed phenotypic characteristics of a mutant deficient in petrobactin import. A mutant lacking all three of the identified ATPases (ΔfatEΔfpuCΔfpuD) exhibited the same growth defect in iron-depleted conditions. Taken together, these results provide the first description of the permease and ATPase proteins required for the import of petrobactin in B. anthracis.
Collapse
Affiliation(s)
- Shandee D Dixon
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI 48104, USA
| | | | | | | | | |
Collapse
|
4
|
Bushell WC, Theise ND. Toward a Unified Field of Study: Longevity, Regeneration, and Protection of Health through Meditation and Related Practices. Ann N Y Acad Sci 2009; 1172:5-19. [DOI: 10.1111/j.1749-6632.2009.04959.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
|
5
|
Francis AW, Ruggiero CE, Koppisch AT, Dong J, Song J, Brettin T, Iyer S. Proteomic analysis of Bacillus anthracis Sterne vegetative cells. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2005; 1748:191-200. [PMID: 15769596 DOI: 10.1016/j.bbapap.2005.01.007] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2004] [Revised: 01/03/2005] [Accepted: 01/13/2005] [Indexed: 10/25/2022]
Abstract
Mass spectrometry and proteomics have found increasing use as tools for the rapid detection of pathogenic bacteria, even when they are in a mixture of non-pathogenic relatives. The success of this technique is greatly augmented by the availability of publicly accessible proteomic databases for specific pathogenic bacteria. To aid proteomic detection analyses for the causative agent of anthrax, we have constructed a comprehensive proteomic catalogue of vegetative Bacillus anthracis Sterne cells using liquid chromatography tandem-mass spectrometry. Proteins were separated by molecular weight or isoelectric point prior to tryptic digestion. Alternatively, the whole protein extract was digested and tryptic peptides were separated by cation exchange chromatography prior to Reverse Phase-LC-MS/MS. The use of three complementary, pre-analytical separation techniques resulted in the identification of 1048 unique proteins, including 694 cytosolic, 153 membrane (including 27 cell wall), and 30 secreted proteins, accounting for 19% of the total predicted proteome. Each identified protein was functionally categorized using the gene attribute database from TIGR CMR. These results provide a large proteomic catalogue of vegetative B. anthracis cells and, coupled with the recent proteomic catalogue of B. anthracis spore proteins, form a thorough summary of proteins expressed in the active and dormant stages of this organism.
Collapse
Affiliation(s)
- Anthony W Francis
- Bioscience Division, Los Alamos National Laboratory, P.O. 1663, Los Alamos, NM 87545, USA
| | | | | | | | | | | | | |
Collapse
|
6
|
Muñiz AE. Lymphocytic vasculitis associated with the anthrax vaccine: case report and review of anthrax vaccination. J Emerg Med 2003; 25:271-6. [PMID: 14585454 DOI: 10.1016/s0736-4679(03)00201-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Anthrax is caused by the spore-forming bacteria Bacillus anthracis. It occurs naturally, but recently has been manufactured as a biological warfare agent. This makes prophylaxis for anthrax an urgent concern and efforts are ongoing for the production of an efficient and safe vaccine. Side effects to the current anthrax vaccine are usually minor and mainly consist of local skin reactions. Occasionally an unusual complication may occur; a case of a patient with lymphocytic vasculitis temporally associated with the anthrax vaccine is reported.
Collapse
Affiliation(s)
- Antonio E Muñiz
- Department of Emergency Medicine and Pediatrics, Medical College of Virginia, 401 N. 12th Street, Richmond, VA 23298-0401, USA
| |
Collapse
|
7
|
Lange JL, Lesikar SE, Rubertone MV, Brundage JF. Comprehensive systematic surveillance for adverse effects of anthrax vaccine adsorbed, US Armed Forces, 1998-2000. Vaccine 2003; 21:1620-8. [PMID: 12639483 DOI: 10.1016/s0264-410x(02)00723-5] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Routine vaccinations of US military personnel with Anthrax Vaccine Adsorbed began in 1998. To systematically identify clinical diagnoses reported more frequently after vaccination than before, all military personnel were retrospectively assigned to pre- or post-vaccination cohorts. Cohort assignments were based on vaccination statuses each day of the 3-year surveillance period. For each cohort, rates of hospitalizations and ambulatory visits for 843 specific diagnoses were calculated using data in a public health surveillance system. Compared to the pre-vaccination cohort, the post-vaccination cohort had statistically higher rates of hospitalizations for 17 diagnoses, of ambulatory visits for 34 diagnoses, and in both clinical settings for one diagnosis (malaria). After accounting for systematic differences in coding/reporting and residual confounding, the number and nature of clinical diagnoses more frequent after anthrax vaccination than before were consistent with expectations due to random variation. This surveillance suggests that Anthrax Vaccine Adsorbed has few, if any, clinically significant adverse effects.
Collapse
Affiliation(s)
- Jeffrey L Lange
- Army Medical Surveillance Activity, US Army Center for Health Promotion and Preventive Medicine, Building T-20, Room 213 (Attn: MCHB-TS-EDM), 6900 Georgia Avenue, NW, Washington, DC 20307-5001, USA
| | | | | | | |
Collapse
|
8
|
Bodasing N, Seaton RA. Anthrax and other microbial threats. Scott Med J 2001; 46:167-70. [PMID: 11852629 DOI: 10.1177/003693300104600605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Affiliation(s)
- N Bodasing
- Department of Infectious Diseases and Tropical Medicine, Brownlee Centre, Gartnavel General Hospital, 1053 Great Western Road, Glasgow G12 OYN
| | | |
Collapse
|
9
|
Use of anthrax vaccine in the United States: recommendations of the Advisory Committee on Immunization Practices. JOURNAL OF TOXICOLOGY. CLINICAL TOXICOLOGY 2001; 39:85-100. [PMID: 11327233 DOI: 10.1081/clt-100102886] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
These recommendations concern the use of aluminum hydroxide adsorbed cell-free anthrax vaccine (Anthrax Vaccine Adsorbed [AVA], BioPort Corporation, Lansing, MI) in the United States for protection against disease caused by Bacillus anthracis. In addition, information is included regarding the use of chemoprophylaxis against B. anthracis.
Collapse
|
10
|
Affiliation(s)
- T C Dixon
- Department of Microbiology, Duke University Medical Center, Durham, NC, USA
| | | | | | | |
Collapse
|
11
|
Abstract
Anthrax lethal toxin (LeTx), consisting of protective antigen (PA) and lethal factor (LF), rapidly kills primary mouse macrophages and macrophage-like cell lines such as RAW 264.7. LF is translocated by PA into the cytosol of target cells, where it acts as a metalloprotease to cleave mitogen-activated protein kinase kinase 1 (MEK1) and possibly other proteins. In this study, we show that proteasome inhibitors such as acetyl-Leu-Leu-norleucinal, MG132, and lactacystin efficiently block LeTx cytotoxicity, whereas other protease inhibitors do not. The inhibitor concentrations that block LF cytotoxicity are similar to those that inhibit the proteasome-dependent IkappaB-alpha degradation induced by lipopolysaccharide. The inhibitors did not interfere with the proteolytic cleavage of MEK1 in LeTx-treated cells, indicating that they do not directly block the proteolytic activity of LF. However, the proteasome inhibitors did prevent ATP depletion, an early effect of LeTx. No overall activation of the proteasome by LeTx was detected, as shown by the cleavage of fluorogenic substrates of the proteasome. All of these results suggest that the proteasome mediates a toxic process initiated by LF in the cell cytosol. This process probably involves degradation of unidentified molecules that are essential for macrophage homeostasis. Moreover, this proteasome-dependent process is an early step in LeTx intoxication, but it is downstream of the cleavage by LF of MEK1 or other putative substrates.
Collapse
Affiliation(s)
- G Tang
- Oral Infection and Immunity Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, Maryland 20892, USA
| | | |
Collapse
|
12
|
Affiliation(s)
- P C Hanna
- Depts of Microbiology and Immunology, Duke University Medical Center, Durham, NC 27710, USA.
| | | |
Collapse
|
13
|
Affiliation(s)
- P Mora-Garcia
- Division of Hematology-Oncology, A2-412 MDCC, UCLA School of Medicine, Los Angeles, California 90095-1752, USA
| | | |
Collapse
|