1
|
Jaworska K, Ludwiczak M, Murawska E, Raczkowska A, Brzostek K. The Regulator OmpR in Yersinia enterocolitica Participates in Iron Homeostasis by Modulating Fur Level and Affecting the Expression of Genes Involved in Iron Uptake. Int J Mol Sci 2021; 22:ijms22031475. [PMID: 33540627 PMCID: PMC7867234 DOI: 10.3390/ijms22031475] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Revised: 01/29/2021] [Accepted: 01/29/2021] [Indexed: 12/02/2022] Open
Abstract
In this study, we found that the loss of OmpR, the response regulator of the two-component EnvZ/OmpR system, increases the cellular level of Fur, the master regulator of iron homeostasis in Y. enterocolitica. Furthermore, we demonstrated that transcription of the fur gene from the YePfur promoter is subject to negative OmpR-dependent regulation. Four putative OmpR-binding sites (OBSs) were indicated by in silico analysis of the fur promoter region, and their removal affected OmpR-dependent fur expression. Moreover, OmpR binds specifically to the predicted OBSs which exhibit a distinct hierarchy of binding affinity. Finally, the data demonstrate that OmpR, by direct binding to the promoters of the fecA, fepA and feoA genes, involved in the iron transport and being under Fur repressor activity, modulates their expression. It seems that the negative effect of OmpR on fecA and fepA transcription is sufficient to counteract the indirect, positive effect of OmpR resulting from decreasing the Fur repressor level. The expression of feoA was positively regulated by OmpR and this mode of action seems to be direct and indirect. Together, the expression of fecA, fepA and feoA in Y. enterocolitica has been proposed to be under a complex mode of regulation involving OmpR and Fur regulators.
Collapse
|
2
|
Alshalchi S, Hayer SS, An R, Munoz-Aguayo J, Flores-Figueroa C, Nguyen R, Lauer D, Olsen K, Alvarez J, Boxrud D, Cardona C, Vidovic S. The Possible Influence of Non-synonymous Point Mutations within the FimA Adhesin of Non-typhoidal Salmonella (NTS) Isolates in the Process of Host Adaptation. Front Microbiol 2017; 8:2030. [PMID: 29089942 PMCID: PMC5651078 DOI: 10.3389/fmicb.2017.02030] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Accepted: 10/04/2017] [Indexed: 12/18/2022] Open
Abstract
Non-typhoidal Salmonella (NTS) remains a global pathogen that affects a wide range of animal species. We analyzed a large number of NTS isolates of different host origins, including Salmonella Heidelberg (n = 80, avian), S. Dublin (50, bovine), S. Typhimurium var 5- (n = 40, porcine), S. 4,5,12,:i:- (n = 40, porcine), S. Cerro (n = 16, bovine), and S. Montevideo (n = 14, bovine), using virulence profiling of the bcfC, mgtC, ssaC, invE, pefA, stn, sopB, and siiE virulence-associated genes, a biofilm production assay, pulsed field gel electrophoresis, and the full-length sequencing of the fimA (adhesin) and iroN (receptor) genes. We determined a key amino acid substitution, A169 (i.e., threonine changed to alanine at position 169), in the FimA protein that changed ligand affinity of FimA toward N-acetyl-D-glucosamine. This finding clearly indicates the important role of non-synonymous single nucleotide polymorphism (nsSNPs) in adhesin functionality that may impact the host tropism of NTS. This nsSNP was found in S. Heidelberg and S. Cerro isolates. Although this was not the case for the IroN receptor, the phylogeny of this receptor and different host origins of NTS isolates were positively correlated, suggesting existence of specific host immune selective pressures on this unique receptor in S. enterica. We found that pefA, a gene encoding major fimbrial subunit, was the most-segregative virulence factor. It was associated with S. Heidelberg, S. Typhimurium var 5- and S. 4,5,12,:i:- but not with the rest of NTS strains. Further, we observed a significantly higher frequency of non-biofilm producers among NTS strains that do not carry pefA (42.5%) compared to S. Heidelberg (2.5%) and S. Typhimurium var 5- (7.5%) and S. 4,5,12,:i:- (0%). This study provides new insights into the host adaptation of avian and mammalian NTS isolates that are based on the bacterial antigens FimA and IroN as well as the interrelationships between host adaptation, overall genetic relatedness, and virulence potential in these NTS isolates.
Collapse
Affiliation(s)
- Sahar Alshalchi
- Department of Veterinary and Biomedical Sciences, University of Minnesota, Minnesota, MN, United States
| | - Shivdeep S Hayer
- Department of Population Medicine, University of Minnesota, Minnesota, MN, United States
| | - Ran An
- Department of Veterinary and Biomedical Sciences, University of Minnesota, Minnesota, MN, United States
| | - Jeannette Munoz-Aguayo
- Mid-Central Research and Outreach Center, University of Minnesota, Minnesota, MN, United States
| | | | - Ryan Nguyen
- Department of Veterinary and Biomedical Sciences, University of Minnesota, Minnesota, MN, United States
| | - Dale Lauer
- Minnesota Poultry Testing Laboratory, University of Minnesota, Minnesota, MN, United States
| | - Karen Olsen
- Veterinary Diagnostic Laboratory, University of Minnesota, Minnesota, MN, United States
| | - Julio Alvarez
- Department of Population Medicine, University of Minnesota, Minnesota, MN, United States
| | - David Boxrud
- Public Health Laboratory, Minnesota Department of Health, Minnesota, MN, United States
| | - Carol Cardona
- Department of Veterinary and Biomedical Sciences, University of Minnesota, Minnesota, MN, United States
| | - Sinisa Vidovic
- Department of Veterinary and Biomedical Sciences, University of Minnesota, Minnesota, MN, United States
| |
Collapse
|
3
|
Stem-Loop Structures within mRNA Coding Sequences Activate Translation Initiation and Mediate Control by Small Regulatory RNAs. Mol Cell 2017; 68:158-170.e3. [DOI: 10.1016/j.molcel.2017.08.015] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Revised: 06/08/2017] [Accepted: 08/18/2017] [Indexed: 11/20/2022]
|
4
|
Zárate-Bonilla LJ, Del Portillo P, Sáenz-Suárez H, Gonzáles-Santos J, Barreto-Sampaio GE, Poutou-Piñales RA, Rey AF, Rey JG. Computational modeling and preliminary iroN, fepA, and cirA gene expression in Salmonella Enteritidis under iron-deficiency-induced conditions. Poult Sci 2014; 93:221-30. [PMID: 24570443 DOI: 10.3382/ps.2012-02993] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Salmonellosis outbreaks in Europe, the United States, and Latin America have been associated with contaminated food derivatives including meat from the poultry industry. Salmonella grown under iron-limiting conditions has the capability to increase concentration of several iron-regulated outer-membrane proteins to augment the acquisition of the metal. These proteins have been proved to have immunogenic properties. Our aim was to increase the relative expression of iroN, fepA, and cirA in Salmonella Enteritidis domestic strain. Furthermore, we proposed a 3-dimensional structure model for each protein to predict and locate antigenic peptides. Our eventual objective is to produce an effective vaccine against regional avian salmonellosis. Two simple factorial designs were carried out to discriminate between 2 nitrogen sources and determine chelating-agent addition timing to augment relative gene expression. Two antigenic peptides located at the external face of each protein and 2 typical domains of iron-regulated outer-membrane proteins, plug and TonB-dep-Rec, were identified from the 3-dimensional models. Tryptone was selected as the best nitrogen source based on growth rate (μx = 0.36 h(-1)) and biomass productivity (Px = 0.9 g•h(-1)•L(-1)) as determined by a general factorial design. Optimum timing for chelating agent addition was in the middle of the log phase, which allowed relative expressions at 4 h of culture. Increase in iroN, fepA, and cirA relative expression was favored by the length of log phase and the addition of chelating agent, which decreased chelating toxicity and enhanced cell growth rate.
Collapse
|
5
|
Cernat RC, Scott KP. Evaluation of novel assays to assess the influence of different iron sources on the growth of Clostridium difficile. Anaerobe 2012; 18:298-304. [PMID: 22554901 DOI: 10.1016/j.anaerobe.2012.04.007] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2011] [Revised: 03/14/2012] [Accepted: 04/16/2012] [Indexed: 01/05/2023]
Abstract
The ability of four Clostridium difficile strains to utilize various exogenous organic and inorganic iron sources for growth under iron-depleted (250 μM DPP) and iron-limited (75 μM DPP) conditions was analyzed in liquid broth cultures grown in tubes and in microtiter plates, and data compared with results from a bioassay developed on solid media. The growth profile of C. difficile varied depending on the iron source and availability. Addition of FeSO(4), FeCl(3), Fe citrate and ferritin allowed growth in an iron-depleted environment whereas glycoproteins (iron-saturated and low-iron lactoferrin, apo- and holo-transferrin) and heme proteins (hemoglobin, hematin and hemin) did not. All iron sources, except lactoferrin, were able to restore bacterial growth under iron-limited conditions to varying extents. The results demonstrated that the broth microtiter assay developed here was reproducible, reliable and convenient for high-throughput analysis of the growth of C. difficile compared to alternative traditional methods.
Collapse
Affiliation(s)
- Ramona C Cernat
- Microbial Ecology, Gut Health Division, Rowett Institute of Nutrition and Health, University of Aberdeen, Bucksburn, UK
| | | |
Collapse
|
6
|
Abstract
Salmonella enterica is a genetically broad species harboring isolates that display considerable antigenic heterogeneity and significant differences in virulence potential. Salmonella generally exhibit an invasive potential and they can survive for extended periods within cells of the immune system. They cause acute or chronic infections that can be local (e.g. gastroenteritis) or systemic (e.g. typhoid). In vivo Salmonella infections are complex with multiple arms of the immune system being engaged. Both humoral and cellular responses can be detected and characterized, but full protective immunity is not always induced, even following natural infection. The murine model has proven to be a fertile ground for exploring immune mechanisms and observations in the mouse have often, although not always, correlated with those in other infectable species, including humans. Host genetic studies have identified a number of mammalian genes that are central to controlling infection, operating both in innate and acquired immune pathways. Vaccines, both oral and parenteral, are available or under development, and these have been used with some success to explore immunity in both model systems and clinically in humans.
Collapse
Affiliation(s)
- Gordon Dougan
- Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Cambridge, UK.
| | | | | | | |
Collapse
|
7
|
Humanized nonobese diabetic-scid IL2rgammanull mice are susceptible to lethal Salmonella Typhi infection. Proc Natl Acad Sci U S A 2010; 107:15589-94. [PMID: 20713716 DOI: 10.1073/pnas.1005566107] [Citation(s) in RCA: 102] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Salmonella enterica serovar Typhi, the cause of typhoid fever, is host-adapted to humans and unable to cause disease in mice. Here, we show that S. Typhi can replicate in vivo in nonobese diabetic (NOD)-scid IL2rgamma(null) mice engrafted with human hematopoietic stem cells (hu-SRC-SCID mice) to cause a lethal infection with pathological and inflammatory cytokine responses resembling human typhoid. In contrast, S. Typhi does not exhibit net replication or cause illness in nonengrafted or immunocompetent control animals. Screening of transposon pools in hu-SRC-SCID mice revealed both known and previously unknown Salmonella virulence determinants, including Salmonella Pathogenicity Islands 1, 2, 3, 4, and 6. Our observations indicate that the presence of human immune cells allows the in vivo replication of S. Typhi in mice. The hu-SRC-SCID mouse provides an unprecedented opportunity to gain insights into S. Typhi pathogenesis and devise strategies for the prevention of typhoid fever.
Collapse
|
8
|
Chanana V, Majumdar S, Rishi P. Involvement of caspase-3, lipid peroxidation and TNF-alpha in causing apoptosis of macrophages by coordinately expressed Salmonella phenotype under stress conditions. Mol Immunol 2006; 44:1551-8. [PMID: 17027970 DOI: 10.1016/j.molimm.2006.08.022] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2006] [Revised: 08/14/2006] [Accepted: 08/22/2006] [Indexed: 11/26/2022]
Abstract
Invasive Salmonella has been reported to induce apoptosis of macrophages as a part of its infection process, which may allow it to avoid detection by the innate immune system. However, the bacterial components capable of inducing apoptosis, particularly under the environments offered by the host have not been fully identified. Therefore, in the present study, attempts were made to evaluate the apoptotic potential of Salmonella enterica serovar Typhi (S. typhi) outer membrane protein expressed under stress conditions like iron, oxidative and anaerobic simulating the in vivo situations encountered by the pathogen. Analysis of data revealed that a coordinately expressed 69kDa outer membrane protein (OMP) expressed with enhanced intensity under iron, oxidative and anaerobic stress conditions caused apoptotic cell death in 51% of macrophages, whereas OMPs of S. typhi extracted under normal conditions accounted for apoptotic cell death in only 31% of macrophages. A significantly enhanced activity of caspase-3 was observed during macrophage-apoptosis induced by this protein. A significant increase in the extent of lipid peroxidation (levels of oxidant) and decrease in the activities of antioxidants was also observed which correlated with the increased generation of tumor necrosis factor-alpha, interleukine-1alpha and interleukine-6. These results suggest that caspase-3 and tumor necrosis factor-alpha in conjunction with other cytokines may induce apoptotic cell death through the up-regulation of oxidants and down-regulation of antioxidants. These findings may be relevant for the better understanding of the disease pathophysiology and for the future developments of diagnostic and preventive strategies during the host-pathogen interactions.
Collapse
Affiliation(s)
- Vishal Chanana
- Department of Microbiology, Panjab University, Chandigarh, India
| | | | | |
Collapse
|
9
|
Chanana V, Majumdar S, Ray P, Sharma M, Rishi P. Coordinated expression and immunogenicity of an outer membrane protein from Salmonella enterica serovar Typhi under iron limitation, oxidative stress and anaerobic conditions. J Biomed Sci 2005; 13:303-12. [PMID: 16362827 DOI: 10.1007/s11373-005-9047-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2005] [Accepted: 10/24/2005] [Indexed: 11/28/2022] Open
Abstract
Successful pathogens overcome the environmental stresses by the coordinated expression of various genes and eventually proteins. Since, the surface of the microbe is likely to come in contact with the host initially, an attempt was made to identify the outer membrane proteins (OMPs), if any, which may get expressed under more than one environmental conditions simulating the in vivo ones. In the present study, Salmonella enterica serovar Typhi was grown under iron-limited, oxidative stress as well as anaerobic conditions and the OMP profiles were compared. A 69 kDa OMP was found to express with enhanced intensity under the selected stress conditions in comparison to normal conditions. The phenotypic similarity among the proteins was assessed on the basis of their molecular weight, cross reactivity and HPLC. The protein expressed under oxidative stress and anaerobic conditions reacted with the antibodies raised against iron-regulated outer membrane protein (IROMP), indicating the sharing of at least some of the epitopes. A single peak observed after subjecting the pooled 69 kDa protein sample and appearance of a single band on SDS-PAGE thereafter, confirmed the purity and phenotypic similarity of the 69 kDa OMP. Reactivity of pooled 69 kDa protein with 85% of sera from typhoid patients revealed the in vivo expression of this protein. The results of this study indicate the coordination of this phenotype under iron stress, oxidative stress and anaerobic conditions. In view of the expression of the 69 kDa protein under the selected stress conditions and their in vivo immunogenicity, these findings may be relevant for the better understanding of the host-microbe interactions and for the further development of diagnostic and preventive strategies.
Collapse
Affiliation(s)
- V Chanana
- Department of Microbiology, Panjab University, Chandigarh, India
| | | | | | | | | |
Collapse
|
10
|
Sood S, Rishi P, Vohra H, Sharma S, Ganguly NK. Cellular immune response induced by Salmonella enterica serotype Typhi iron-regulated outer-membrane proteins at peripheral and mucosal levels. J Med Microbiol 2005; 54:815-821. [PMID: 16091431 DOI: 10.1099/jmm.0.46042-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The role of purified iron-regulated outer-membrane proteins (IROMPs) from Salmonella enterica serotype Typhi in modulation of specific T-cell responses was studied. The cellular immune response induced by IROMPs was measured by assessing the delayed-type hypersensitivity (DTH) response, lymphocyte proliferation, T-cell phenotyping and cytokine-producing cells using lymphocytes isolated from the spleen and Peyer's patches of IROMPs-immunized, immunized-challenged, infected and control mice. IROMPs immunization resulted in an enhanced DTH response and exhibited a significant increase in the protein-specific proliferative response of lymphocyte from the spleen as well as Peyer's patches. A significant increase was also observed in the ratio of CD4+/CD8+ cells in the immunized mice as compared to the infected mice. Results of the cytokine analysis revealed that during the initial period there was increased production of interleukin (IL)-2- and interferon (IFN)-gamma-producing cells in the spleen and Peyer's patches, indicating a Th1 type response, whereas in the later period of the study, increased production of IL-4-producing cells suggested a Th2 type response. The results of this study suggest a role for S. Typhi IROMPs in modulating the cellular immune response at peripheral and mucosal levels.
Collapse
Affiliation(s)
- Shaloo Sood
- Department of Experimental Medicine and Biotechnology, Postgraduate Institute of Medical Education and Research, Chandigarh, India 2Department of Microbiology, Panjab University, Chandigarh 160 014, India
| | - Praveen Rishi
- Department of Experimental Medicine and Biotechnology, Postgraduate Institute of Medical Education and Research, Chandigarh, India 2Department of Microbiology, Panjab University, Chandigarh 160 014, India
| | - Harpreet Vohra
- Department of Experimental Medicine and Biotechnology, Postgraduate Institute of Medical Education and Research, Chandigarh, India 2Department of Microbiology, Panjab University, Chandigarh 160 014, India
| | - Saroj Sharma
- Department of Experimental Medicine and Biotechnology, Postgraduate Institute of Medical Education and Research, Chandigarh, India 2Department of Microbiology, Panjab University, Chandigarh 160 014, India
| | - Nirmal K Ganguly
- Department of Experimental Medicine and Biotechnology, Postgraduate Institute of Medical Education and Research, Chandigarh, India 2Department of Microbiology, Panjab University, Chandigarh 160 014, India
| |
Collapse
|
11
|
Sood S, Rishi P, Dhawan V, Sharma S, Ganguly NK. Protection mediated by antibodies to iron-regulated outer-membrane proteins of S. typhi in a mouse peritonitis model. Mol Cell Biochem 2005; 273:69-78. [PMID: 16013441 DOI: 10.1007/s11010-005-7756-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Iron limitation induces the expression of iron-regulated outer-membrane proteins, which are not expressed under iron sufficient growth conditions. In the present study, these proteins were purified in order to evaluate their protective potential in the experimental model. Anti IROMPs antiserum was raised in rabbits. In mice, passively transferred anti-IROMPs antibodies provided 60% protection against the serovar Typhi challenge dose (9.6 LD50). The hyperimmune serum containing anti-IROMPs antibodies were also found to be bactericidal in the presence of complement whereas no bacterial killing was observed with pre-immunized serum. Bactericidal titre of anti-IROMPs serum was fond to be 2000 as more than 50% killing was observed with serum diluted to 1:2000. The role of IROMPs was assessed in actively-immunized mice followed by challenge with serovar Typhi. These proteins provided protection in 90% mice against challenge (480 LD50) with the pathogen. The levels of isotypes of antibodies (IgG, IgM & IgA) in the sera and secretory antibodies (sIgA) in the gut fluid of immunized mice correlated with the protection. This study, thus indicates that anti IROMPs antibodies may play an important role in providing protection at systemic as well as at mucosal level.
Collapse
Affiliation(s)
- Shaloo Sood
- Department of Experimental Medicine and Biotechnology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | | | | | | | | |
Collapse
|
12
|
Chanana V, Sehgal R, Rishi P. Salmonella typhi iron-regulated outer-membrane proteins cause oedema and hyperalgesia during inflammation induced in a rat model. J Med Microbiol 2005; 54:421-423. [PMID: 15770031 DOI: 10.1099/jmm.0.45907-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Vishal Chanana
- Department of Microbiology, Panjab University, Chandigarh-160014, India 2Central Research Institute, Kasauli, H. P. India
| | - Rakesh Sehgal
- Department of Microbiology, Panjab University, Chandigarh-160014, India 2Central Research Institute, Kasauli, H. P. India
| | - Praveen Rishi
- Department of Microbiology, Panjab University, Chandigarh-160014, India 2Central Research Institute, Kasauli, H. P. India
| |
Collapse
|
13
|
Apoptotic cell death of macrophages by iron-stressed Salmonella enterica serovar Typhimurium. World J Microbiol Biotechnol 2004. [DOI: 10.1007/s11274-004-3044-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
14
|
Ho WL, Yu RC, Chou CC. Effect of iron limitation on the growth and cytotoxin production of Salmonella choleraesuis SC-5. Int J Food Microbiol 2004; 90:295-302. [PMID: 14751684 DOI: 10.1016/s0168-1605(03)00316-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
This study investigated the effect of iron limitation on the growth and cytotoxin production of Salmonella choleraesuis and examined the iron-accruing capability of various Salmonella strains. It was found that the growth of S. choleraesuis SC-5 was retarded by the presence of iron-chelating agents, 2,2'-dipyridyl or ethylenediamine di-o-hydroxyphenylactic acid (EDDA). Addition of 2,2'-dipyridyl to Trypticase soy broth (TSB) resulted in a smaller maximum population of S. choleraesuis noted at the stationary phase, while addition of EDDA in TSB only caused an extended period of lag phase. A significant increase in cytotoxin production was found when S. choleraesuis SC-5 was cultured in iron-limited TSB containing 2,2'-dipyridyl. On the other hand, pre-culture in an iron-limited medium increased the growth of S. choleraesuis SC-5 in mouse serum with or without complement inactivated. Testing with a plate assay method revealed that the ability and efficiency of Salmonella to acquire iron under iron-limited condition varied with strains, and the kinds and dosages of iron-containing compounds present.
Collapse
Affiliation(s)
- Wei-Li Ho
- Department of Food Science, Ching Kuo Institute of Management and Health, Keelung, Taiwan
| | | | | |
Collapse
|
15
|
Almirón M, Martínez M, Sanjuan N, Ugalde RA. Ferrochelatase is present in Brucella abortus and is critical for its intracellular survival and virulence. Infect Immun 2001; 69:6225-30. [PMID: 11553564 PMCID: PMC98755 DOI: 10.1128/iai.69.10.6225-6230.2001] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2001] [Accepted: 06/25/2001] [Indexed: 11/20/2022] Open
Abstract
Brucella spp. are pathogenic bacteria that cause brucellosis, an animal disease which can also affect humans. Although understanding the pathogenesis is important for the health of animals and humans, little is known about virulence factors associated with it. In order for chronic disease to be established, Brucella spp. have developed the ability to survive inside phagocytes by evading cell defenses. It hides inside vacuoles, where it then replicates, indicating that it has an active metabolism. The purpose of this work was to obtain better insight into the intracellular metabolism of Brucella abortus. During a B. abortus genomic sequencing project, a clone coding a putative gene homologous to hemH was identified and sequenced. The amino acid sequence revealed high homology to members of the ferrochelatase family. A knockout mutant displayed auxotrophy for hemin, defective intracellular survival inside J774 and HeLa cells, and lack of virulence in BALB/c mice. This phenotype was overcome by complementing the mutant strain with a plasmid harboring wild-type hemH. These data demonstrate that B. abortus synthesizes its own heme and also has the ability to use an external source of heme; however, inside cells, there is not enough available heme to support its intracellular metabolism. It is concluded that ferrochelatase is essential for the multiplication and intracellular survival of B. abortus and thus for the establishment of chronic disease as well.
Collapse
Affiliation(s)
- M Almirón
- Instituto de Investigaciones Biotecnológicas, Consejo Nacional de Investigaciones Científicas y Técnicas, Universidad Nacional de General San Martín, Buenos Aires, Argentina
| | | | | | | |
Collapse
|
16
|
Scott DC, Cao Z, Qi Z, Bauler M, Igo JD, Newton SM, Klebba PE. Exchangeability of N termini in the ligand-gated porins of Escherichia coli. J Biol Chem 2001; 276:13025-33. [PMID: 11278876 DOI: 10.1074/jbc.m011282200] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The ferric siderophore transporters of the Gram-negative bacterial outer membrane manifest a unique architecture: Their N termini fold into a globular domain that lodges within, and physically obstructs, a transmembrane porin beta-barrel formed by their C termini. We exchanged and deleted the N termini of two such siderophore receptors, FepA and FhuA, which recognize and transport ferric enterobactin and ferrichrome, respectively. The resultant chimeric proteins and empty beta-barrels avidly bound appropriate ligands, including iron complexes, protein toxins, and viruses. Thus, the ability to recognize and discriminate these molecules fully originates in the transmembrane beta-barrel domain. Both the hybrid and the deletion proteins also transported the ferric siderophore that they bound. The FepA constructs showed less transport activity than wild type receptor protein, but the FhuA constructs functioned with turnover numbers that were equivalent to wild type. The mutant proteins displayed the full range of transport functionalities, despite their aberrant or missing N termini, confirming (Braun, M., Killmann, H., and Braun, V. (1999) Mol. Microbiol. 33, 1037-1049) that the globular domain within the pore is dispensable to the siderophore internalization reaction, and when present, acts without specificity during solute uptake. These and other data suggest a transport process in which siderophore receptors undergo multiple conformational states that ultimately expel the N terminus from the channel concomitant with solute internalization.
Collapse
Affiliation(s)
- D C Scott
- Department of Chemistry & Biochemistry, University of Oklahoma, Norman, Oklahoma 73019, USA
| | | | | | | | | | | | | |
Collapse
|
17
|
Rabsch W, Voigt W, Reissbrodt R, Tsolis RM, Bäumler AJ. Salmonella typhimurium IroN and FepA proteins mediate uptake of enterobactin but differ in their specificity for other siderophores. J Bacteriol 1999; 181:3610-2. [PMID: 10348879 PMCID: PMC93834 DOI: 10.1128/jb.181.11.3610-3612.1999] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Salmonella typhimurium possesses two outer membrane receptor proteins, IroN and FepA, which have been implicated in the uptake of enterobactin. To determine whether both receptors have identical substrate specificities, fepA and iroN mutants and a double mutant were characterized. While both receptors transported enterobactin, the uptake of corynebactin and myxochelin C was selectively mediated by IroN and FepA, respectively.
Collapse
Affiliation(s)
- W Rabsch
- National Reference Center for Salmonellae and Other Enterics, Robert Koch-Institute, D-38855 Wernigerode, Germany
| | | | | | | | | |
Collapse
|
18
|
Segurado M, López-Aragón R, Calera JA, Fernández-Abalos JM, Leal F. Zinc-regulated biosynthesis of immunodominant antigens from Aspergillus spp. Infect Immun 1999; 67:2377-82. [PMID: 10225898 PMCID: PMC115981 DOI: 10.1128/iai.67.5.2377-2382.1999] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
ASPND1 and ASPF2 are immunodominant antigens from Aspergillus nidulans and A. fumigatus, respectively, that are readily synthesized in infections in the human host, as demonstrated by their reactivity with more than 80% of sera from patients with aspergilloma or allergic bronchopulmonary aspergillosis. We demonstrate here that both antigens are exclusively produced under situations of low bioavailability of free Zn2+. Addition of micromolar concentrations of Zn2+ to the culture medium strongly stimulated Aspergillus growth but totally inhibited ASPND1 or ASPF2 production. This effect was specific, since other divalent metals had no effect. Removal of endogenous Zn2+ by a chelator also stimulated ASPND1 production, and the effect was specifically reversed by Zn2+. These results suggest a possible role of these antigens in the survival of the fungus in the lungs.
Collapse
Affiliation(s)
- M Segurado
- Departamento de Microbiología y Genética, Universidad de Salamanca, 37007 Salamanca, Spain
| | | | | | | | | |
Collapse
|
19
|
Bäumler AJ, Norris TL, Lasco T, Voight W, Reissbrodt R, Rabsch W, Heffron F. IroN, a novel outer membrane siderophore receptor characteristic of Salmonella enterica. J Bacteriol 1998; 180:1446-53. [PMID: 9515912 PMCID: PMC107043 DOI: 10.1128/jb.180.6.1446-1453.1998] [Citation(s) in RCA: 109] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/1997] [Accepted: 01/06/1998] [Indexed: 02/06/2023] Open
Abstract
Speciation in enterobacteria involved horizontal gene transfer. Therefore, analysis of genes acquired by horizontal transfer that are present in one species but not its close relatives is expected to give insights into how new bacterial species were formed. In this study we characterize iroN, a gene located downstream of the iroBC operon in the iroA locus of Salmonella enterica serotype Typhi. Like iroBC, the iroN gene is present in all phylogenetic lineages of S. enterica but is absent from closely related species such as Salmonella bongori or Escherichia coli. Comparison of the deduced amino acid sequence of iroN with other proteins suggested that this gene encodes an outer membrane siderophore receptor protein. Mutational analysis in S. enterica and expression in E. coli identified a 78-kDa outer membrane protein as the iroN gene product. When introduced into an E. coli fepA cir fiu aroB mutant on a cosmid, iroN mediated utilization of structurally related catecholate siderophores, including N-(2,3-dihydroxybenzoyl)-L-serine, myxochelin A, benzaldehyde-2,3-dihydroxybenzhydrazone, 2-N,6-N-bis(2,3-dihydroxybenzoyl)-L-lysine, 2-N,6-N-bis(2,3-dihydroxybenzoyl)-L-lysine amide, and enterochelin. These results suggest that the iroA locus functions in iron acquisition in S. enterica.
Collapse
MESH Headings
- Amino Acid Sequence
- Bacterial Outer Membrane Proteins
- Cloning, Molecular
- Cosmids
- DNA, Bacterial/analysis
- DNA, Bacterial/genetics
- Escherichia coli/genetics
- Escherichia coli/metabolism
- Gene Expression
- Genes, Bacterial
- Molecular Sequence Data
- Mutagenesis, Insertional
- Operon
- Phylogeny
- Receptors, Cell Surface/genetics
- Receptors, Cell Surface/metabolism
- Recombination, Genetic
- Restriction Mapping
- Salmonella/genetics
- Salmonella/metabolism
- Salmonella enterica/genetics
- Salmonella enterica/metabolism
- Sequence Alignment
- Sequence Analysis, DNA
- Sequence Homology, Amino Acid
- Siderophores/metabolism
- Species Specificity
Collapse
Affiliation(s)
- A J Bäumler
- Department of Medical Microbiology and Immunology, Texas A&M University, College Station 77843-1114, USA.
| | | | | | | | | | | | | |
Collapse
|
20
|
Whitby PW, Sim KE, Morton DJ, Patel JA, Stull TL. Transcription of genes encoding iron and heme acquisition proteins of Haemophilus influenzae during acute otitis media. Infect Immun 1997; 65:4696-700. [PMID: 9353052 PMCID: PMC175673 DOI: 10.1128/iai.65.11.4696-4700.1997] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Unencapsulated Haemophilus influenzae is the second most common etiologic agent of otitis media in children. H. influenzae requires heme for aerobic growth in vitro and is able to utilize hemoglobin and complexes of heme-hemopexin, heme-albumin, and hemoglobin-haptoglobin and ferritransferrin as sources of iron and heme in vitro. Several of the acquisition mechanisms have been characterized and been shown to be heme repressible in vitro. However, little is known about the expression of heme and/or iron acquisition mechanisms during infections in the middle ear. This study was performed to determine if the genes encoding heme and iron acquisition proteins are transcribed during in vivo growth and to compare these findings with those for samples grown in vitro. Reverse transcriptase PCR (RT-PCR) was used to analyze total RNA fractions derived from in vitro- and in vivo-grown H. influenzae. Genes encoding the transferrin-binding proteins TbpA and TbpB, the 100-kDa hemopexin-binding protein HxuA, and the hemoglobin-binding protein HgpA were transcribed during otitis media. Twelve middle ear fluid samples were analyzed by blind RT-PCR to determine the transcriptional status of these genes in H. influenzae during otitis media. Five isolates had transcripts corresponding to tbpA, tbpB, and hxuA. The presence of hgpA transcripts was variable, depending on the presence of hgpA in the genome of the H. influenzae isolate. Samples without H. influenzae gene transcripts contained other etiologic agents commonly causing otitis media. These data demonstrate that H. influenzae iron and/or heme acquisition genes are transcribed during otitis media and suggest that the microenvironment during acute otitis media starves H. influenzae of heme.
Collapse
Affiliation(s)
- P W Whitby
- Department of Pediatrics, University of Oklahoma Health Sciences Center, Oklahoma City 73104, USA
| | | | | | | | | |
Collapse
|
21
|
Worst DJ, Sparrius M, Kuipers EJ, Kusters JG, de Graaff J. Human serum antibody response against iron-repressible outer membrane proteins of Helicobacter pylori. FEMS Microbiol Lett 1996; 144:29-32. [PMID: 8870248 DOI: 10.1111/j.1574-6968.1996.tb08504.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
In Helicobacter pylori, in vitro iron limitation induces the expression of several iron repressible outer membrane proteins (IROMPs), which are not expressed under normal growth conditions. To substantiate their proposed role in virulence of H. pylori, we determined whether these IROMPs are also expressed in vivo. Therefore, we tested whether sera of patients with H. pylori infection contained antibodies against IROMPs. All sera from 20 H. pylori positive patients showed a clear immune response against a 77 kDa heme-binding IROMP in an immunoblot assay. Antibody responses against the other IROMPs were also found, but with lower frequencies. Serum samples from 18 patients negative for H. pylori infection did not show any immunoreactivity with IROMPs. These results indicate that the IROMPs of H. pylori are immunogenic and are expressed in vivo.
Collapse
Affiliation(s)
- D J Worst
- Department of Medical Microbiology, Vrije Universiteit, Amsterdom, The Netherlands.
| | | | | | | | | |
Collapse
|
22
|
Fica AE, Prat-Miranda S, Fernandez-Ricci A, D'Ottone K, Cabello FC. Epidemic typhoid in Chile: analysis by molecular and conventional methods of Salmonella typhi strain diversity in epidemic (1977 and 1981) and nonepidemic (1990) years. J Clin Microbiol 1996; 34:1701-7. [PMID: 8784573 PMCID: PMC229098 DOI: 10.1128/jcm.34.7.1701-1707.1996] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
From 1977 to 1986, Chile experienced an important typhoid fever epidemic, despite statistics that indicated apparently improving levels of sanitation of drinking water and sewage disposal. The lack of antibiotic resistance among the Salmonella typhi strains isolated during this period, the mild clinical presentation of the disease, and the initially low level of efficacy of the S. typhi Ty21a vaccine in the population exposed to the epidemic suggested that this epidemic might have resulted from the dissemination of S. typhi strains with unique characteristics. To investigate this hypothesis, we used conventional methods (bacteriophage typing and biotyping) and molecular methods (restriction fragment length polymorphism analysis, ribotyping, IS200 typing, and PCR amplification of the fliC-d gene) to study a population of 149 S. typhi isolates during 1977, 1981, and 1990, the years that included periods with low (when the disease was endemic) and high (when the disease was epidemic) morbidities. Our results indicate that these S. typhi isolates in Chile represent a number of highly diverse variants of the clone of S. typhi with a worldwide distribution described by Selander et al. (R. K. Selander, P. Beltran, N.H. Smith, R. Helmuth, F.A. Rubin, D.J. Kopecko, K. Ferris, B.D. Tall, A. Cravioto, and J.M. Musser, Infect. Immun. 58:2262-2275, 1990). For example, we detected 26 PstI and 10 ClaI ribotypes among 47 and 16 S. typhi strains belonging to this clone, respectively. These results suggest that the Chilean epidemic was probably produced by multiple sources of infection because of deficient sanitary conditions. These findings illustrate the usefulness of molecular methods for characterizing the potential causes of the typhoid epidemics and the possible routes of transmission of S. typhi strains in typhoid epidemics.
Collapse
Affiliation(s)
- A E Fica
- Department of Microbiology and Immunology, New York Medical College, Valhalla 10595, USA
| | | | | | | | | |
Collapse
|
23
|
Aron L, Alekshun M, Perlee L, Schwartz I, Godfrey HP, Cabello FC. Cloning and DNA sequence analysis of bmpC, a gene encoding a potential membrane lipoprotein of Borrelia burgdorferi. FEMS Microbiol Lett 1994; 123:75-82. [PMID: 7988902 DOI: 10.1111/j.1574-6968.1994.tb07204.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Immunoscreening of a lambda gt11 genomic library of Borrelia burgdorferi expressed in Escherichia coli permitted detection of a clone containing a partial sequence of a B. burgdorferi gene encoding a protein with significant homology to TmpC of Treponema pallidum. Subsequent cloning and DNA sequence analysis revealed an open reading frame encoding a protein with 353 amino acid residues. The open reading frame is preceded by putative promoter sequences and a ribosome binding site, and is initiated with a TTG. The putative protein shares 26% identity with TmpC, contains a signal peptidase II sequence, and is also homologous to the gene products of the recently described bmpA and bmpB of B. burgdorferi. This gene has been designated bmpC. Additional sequencing and restriction analysis indicate that it is located at approximately 400 kbp on the chromosomal map of B. burgdorferi, immediately upstream of bmpA and bmpB.
Collapse
Affiliation(s)
- L Aron
- Department of Microbiology and Immunology, New York Medical College, Valhalla 10595
| | | | | | | | | | | |
Collapse
|
24
|
Furman M, Fica A, Saxena M, Di Fabio JL, Cabello FC. Salmonella typhi iron uptake mutants are attenuated in mice. Infect Immun 1994; 62:4091-4. [PMID: 8063432 PMCID: PMC303076 DOI: 10.1128/iai.62.9.4091-4094.1994] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Iron starvation interferes drastically with the multiplication and virulence of Salmonella typhi mutants defective in enterochelin synthesis or enterochelin transport. Growth of these mutants is inhibited in the presence of human sera and unsaturated transferrin and is restored by fully saturated transferrin. The mutants exhibit decreased ability to grow in HeLa cell monolayers and are attenuated in mice. These findings are consistent with the S. typhi enterochelin system playing a role in the pathogenesis of typhoid fever.
Collapse
Affiliation(s)
- M Furman
- Department of Microbiology and Immunology, New York Medical College, Valhalla 10595
| | | | | | | | | |
Collapse
|
25
|
Abstract
A Salmonella typhi conjugated vaccine was prepared by covalently linking the antigenic O-polysaccharide, selectively activated by periodate oxidation, to tetanus toxoid via reductive amination. The immunogenicity of the conjugate (O-TT) was examined by injecting Balb/c mice with 5 micrograms of the conjugate and Alhydrogel as adjuvant, boosting 14 and 28 days after the primary immunization, and quantification of the development of anti-polysaccharide and anti-tetanus toxoid antibodies by enzyme-linked immunosorbent assay. Mean anti-O-chain titres after the first and second boost were 129 and 502, respectively, while anti-tetanus toxoid titres were 159 and 1000, respectively. Anti-O-polysaccharide antibodies exhibited complement-mediated bactericidal activity against S. typhi. Immunized mice were fully protected against challenge with 10 LD50 of S. typhi Ty2 (p < 0.001) and partially protected against challenge with 100 LD50 of S. typhi Ty2 (p < 0.04).
Collapse
Affiliation(s)
- M Saxena
- Bacterial Products Division, Bureau of Biologics, Tunney's Pasture, Ottawa, Ontario, Canada
| | | |
Collapse
|
26
|
Schwartz D, Konforti N, Perry R, Goossens H, Butzler JP, Williams P, Goldhar J. Iron-regulated proteins in outer membranes of Campylobacter jejuni diarrhoea isolates and immune response to the proteins in patients. ZENTRALBLATT FUR BAKTERIOLOGIE : INTERNATIONAL JOURNAL OF MEDICAL MICROBIOLOGY 1994; 280:338-47. [PMID: 8167428 DOI: 10.1016/s0934-8840(11)80596-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The outer membrane protein (OMP) profiles from 8 Campylobacter jejuni and 5 Campylobacter coli fecal isolates grown under various conditions were compared by SDS-PAGE. The bacteria were grown under usual conditions, in iron-deficient medium (Dip) and on iron-supplemented medium (Fe). The OMP profiles of most bacterial strains grown under usual conditions, or in the Fe-supplemented medium, contained four major bands of approximately 31, 45, 63-66 and 97 kDa, and in addition, a number of minor bands. It was found that OMP from 10 of 13 strains tested and grown on iron deficient medium contained an intensive band of a protein in the molecular weight region of 76 kDa which was lacking in the OMP of bacteria grown in the presence of iron (iron-regulated protein). Sera from 11 children with C. jejuni infection analyzed by Western blot recognized the 76 kDa bands, in contrast to only one out of 10 control sera from healthy children. The Western-blot experiments demonstrated also various bands of other OMP components, both in OMP-Dip and OMP-Fe. The 45 kDa (porin protein) was recognized by all 11 serum samples from C. jejuni-infected patients and in 8 out of 10 control sera. The data suggested that the 76 kDa iron-regulated protein was expressed by bacteria during infection and it stimulated the immune response in children infected with C. jejuni.
Collapse
Affiliation(s)
- D Schwartz
- Microbiology Laboratory, Sourasky (Ichilov Medical Center), Tel-Aviv, Israel
| | | | | | | | | | | | | |
Collapse
|
27
|
Hooke AM, Cerquetti MC, Zeligs BJ, Wang Z, Hoberg K, Bellanti JA. Genetically stable temperature-sensitive mutants of Salmonella typhi induce protection in mice. Vaccine 1993; 11:1386-9. [PMID: 8310758 DOI: 10.1016/0264-410x(93)90166-u] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Temperature-sensitive (ts) mutants of Salmonella typhi were isolated following treatment with nitrosoguanidine, and characterized with respect to cut-off temperature, ts phenotype and reversion frequency. Linkage of the ts mutations to selectable chromosomal markers was established by generalized transduction with bacteriophage phage Vi I, and the appropriate antibiotic resistances were transduced into the ts mutants. Multiple mutant S. typhi were then constructed by combining three independent ts mutations in one strain, utilizing linkage of three of the mutations to erythromycin-, streptomycin- and methylglyoxal-resistance. Several recombinants are genetically stable, with calculated reversion rates of less than 10(-22), and induce both protection from intraperitoneal challenge with the virulent parental wild-type S. typhi in mice and the formation of antibodies to the somatic O-9 and O-12, the flagellar H and the capsular Vi antigens.
Collapse
Affiliation(s)
- A M Hooke
- International Center for Interdisciplinary Studies of Immunology, Georgetown University School of Medicine, Washington, DC 20007
| | | | | | | | | | | |
Collapse
|
28
|
Nikolova S, Vesselinova A, Veljanov D. Role of iron in pathogenesis of guinea pigs infected with Yersinia enterocolitica 0:3. ZENTRALBLATT FUR VETERINARMEDIZIN. REIHE B. JOURNAL OF VETERINARY MEDICINE. SERIES B 1993; 40:525-32. [PMID: 8122441 DOI: 10.1111/j.1439-0450.1993.tb00173.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Examined have been the pathogenesis of guinea pigs preliminarily overload with iron, and infected with Yersinia enterocolitica 0:3 in a logarithmic and stationary phase of development, cultivated at 25 degrees C and 37 degrees C. Dextrofer-100 (Fedex-100) medicine have been used as an iron source. The results show that in spite of the phase of development and cultivation temperature, the iron excess does not increase the bacterial virulence of the strain used so far. The morphological changes in the mesenterial lymphatic nodes, small intestines, spleen and liver of guinea pigs treated with iron, and then, infected with Y. enterocolitica, are more slightly expressed as compared with animals infected with Y. enterocolitica only. The investigations suggested so far, have attested that Yersinia enterocolitica 0:3 does not contain a gene responsible for the synthesis of the protein participating in iron uptake.
Collapse
Affiliation(s)
- S Nikolova
- Institute of Microbiology, Bulgarian Academy of Sciences, Sofia
| | | | | |
Collapse
|
29
|
Wedderkopp A, Primal SV, Silva S, Little PB. Differences in protein expression of Haemophilus somnus grown under conditions of iron-restriction. Vet Microbiol 1993; 35:91-100. [PMID: 8362497 DOI: 10.1016/0378-1135(93)90118-q] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Outer membrane protein profiles were compared in 14 H. somnus strains isolated from brain and lung lesions as well as from the genital tract of asymptomatic carriers during in vitro growth under iron-restricted conditions. Ethylenediamine-di-O-hydroxyphenyl acetic acid (EDDA) was used to obtain iron-restricted conditions in media used for this study. The outer membrane protein profiles were studied by the discontinuous sodium dodecyl sulfate-polyacrylamide gel electrophoretic system (SDS-PAGE), and the proteins were stained with silver or transferred to nitrocellulose sheets and western blots conducted. Growth under iron-restricted conditions resulted in the induction of outer membrane proteins in most H. somnus strains examined. Studies also indicated differences among H. somnus strains in the number of induced proteins and their molecular weights but the results did not indicate a specific relationship between these strain-dependent differences and tissue trophism. Western blot analysis revealed a high degree of immunological relatedness among strains of H. somnus in their iron-regulated proteins. However, hyperimmune serum used in these assays failed to recognize certain iron-regulated proteins expressed by some H. somnus strains, a finding which may have important implications for the induction of protective immunity in cattle against this bovine pathogen.
Collapse
Affiliation(s)
- A Wedderkopp
- Department of Pathology and Epidemiology, National Veterinary Laboratory, Copenhagen, Denmark
| | | | | | | |
Collapse
|
30
|
Verdugo-Rodríguez A, López-Vidal Y, Puente JL, Ruíz-Placios GM, Calva E. Early diagnosis of typhoid fever by an enzyme immunoassay using Salmonella typhi outer membrane protein preparations. Eur J Clin Microbiol Infect Dis 1993; 12:248-54. [PMID: 8513812 DOI: 10.1007/bf01967254] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
An enzyme immunoassay (EIA) for detection of serum antibodies in patients with typhoid fever was developed using Salmonella typhi outer membrane protein (OMP) preparations as antigen. Acute phase (first week) sera from adult typhoid fever patients were tested as well as sera from the following control groups: adult travellers with diarrhea caused by enterotoxigenic Escherichia coli, children infected with Campylobacter jejuni, healthy Mexican adult blood donors, and adults with septicemia caused by other organisms. At a 1:3,125 serum dilution, the mean absorbance values were 1.41 in the typhoid fever patients, and 0.57, 0.55, 0.51 and 0.52 in the respective control groups. Inhibition EIA studies using OMP preparations or lipopolysaccharide (LPS) as free antigen indicated that proteins can play an important role in the detection of antibodies in early typhoid fever. This EIA may be useful for the diagnosis of typhoid fever since results were obtained within about five hours and in an endemic area antibodies against Salmonella typhi OMP preparations appear early in the course of the disease.
Collapse
Affiliation(s)
- A Verdugo-Rodríguez
- Departamento de Biología Molecular, Universidad Nacional Autónoma de México, Cuernavaca, Morelos
| | | | | | | | | |
Collapse
|
31
|
Aron L, Di Fabio J, Cabello FC. Salmonella typhi O:9,12 polysaccharide-protein conjugates: characterization and immunoreactivity with pooled and individual normal human sera, sera from patients with paratyphoid A and B and typhoid fever, and animal sera. J Clin Microbiol 1993; 31:975-8. [PMID: 7681853 PMCID: PMC263597 DOI: 10.1128/jcm.31.4.975-978.1993] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Polysaccharide of O:9,12 specificity purified from Salmonella typhi was conjugated to tetanus toxoid or bovine serum albumin in order to obtain defined antigenic material that would contain O chain free of other S. typhi antigens and that would be suitable for characterizing host humoral response to only S. typhi O-chain antigens. These artificial conjugates were strongly reactive in immunodots with 18 pooled and 3 individual serum samples from patients with typhoid fever and with rabbit anti-Salmonella O antiserum (group D, factors 1, 9, and 12). They reacted weakly with one serum sample from one human with paratyphoid A. These results suggest that the periodate oxidation and the reductive amination used in the conjugation conserved the immunogenicity of the O chain and allowed its absorption to nitrocellulose. They also suggest that the bovine serum albumin conjugate could be used in the diagnosis of S. typhi infections as normal sera may react with the protein molecule of the tetanus toxoid conjugate.
Collapse
Affiliation(s)
- L Aron
- Department of Microbiology and Immunology, New York Medical College, Valhalla 10595
| | | | | |
Collapse
|
32
|
Aron L, Faundez G, Gonzalez C, Roessler E, Cabello F. Lipopolysaccharide-independent radioimmunoprecipitation and identification of structural and in vivo induced immunogenic surface proteins of Salmonella typhi in typhoid fever. Vaccine 1993; 11:10-7. [PMID: 8427032 DOI: 10.1016/0264-410x(93)90334-t] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The humoral response to Salmonella typhi is important for protective immunity against typhoid fever, as indicated by the protection obtained with killed cell vaccines and component vaccines (outer membrane proteins, Vi antigen) in animals and human beings. Nonetheless, analysis and interpretation of host humoral immune response to S. typhi surface antigens have been difficult because of the complex structure of the S. typhi envelope and the lack of purified reagents for detection of immune response to individual surface components. Normal and convalescent human sera from typhoid fever patients were absorbed with S. typhi lipopolysaccharide. These sera were used in radioimmunoprecipitation assays of whole S. typhi cells and S. typhi membranes labelled with either 125I or 35S-methionine. This strategy has permitted the unequivocal identification of a humoral immune response to structural and in vivo induced outer membrane proteins of S. typhi. In this manner, we have identified the porins, lipoprotein, the iron-starvation-induced proteins, and three proteins of 30, 18.5 and 15 kDa as surface-exposed immunogens of S. typhi in patients with typhoid fever. These studies suggest that further experimental work is needed to characterize the relevance of both anti-S. typhi outer membrane protein and antilipopolysaccharide antibodies in recovery from S. typhi infections and protective immunity.
Collapse
Affiliation(s)
- L Aron
- Department of Microbiology and Immunology, New York Medical College, Valhalla 10595
| | | | | | | | | |
Collapse
|
33
|
Singh SP, Upshaw Y, Abdullah T, Singh SR, Klebba PE. Structural relatedness of enteric bacterial porins assessed with monoclonal antibodies to Salmonella typhimurium OmpD and OmpC. J Bacteriol 1992; 174:1965-73. [PMID: 1312535 PMCID: PMC205803 DOI: 10.1128/jb.174.6.1965-1973.1992] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The immunochemistry and structure of enteric bacterial porins are critical to the understanding of the immune response to bacterial infection. We raised 41 monoclonal antibodies (MAbs) to Salmonella typhimurium OmpD and OmpC porin trimers and monomers. Enzyme-linked immunosorbent assays, immunoprecipitations, and/or Western immunoblot techniques indicated that 39 MAbs (11 anti-trimer and 28 anti-monomer) in the panel are porin specific and one binds to the lipopolysaccharide; the specificity of the remaining MAb probably lies in the porin-lipopolysaccharide complex. Among the porin-specific MAbs, 10 bound cell-surface-exposed epitopes, one reacted with a periplasmic epitope, and the remaining 28 recognized determinants that are buried within the outer membrane bilayer. Many of the MAbs reacting with surface-exposed epitopes were highly specific, recognizing only the homologous porin trimers; this suggests that the cell-surface-exposed regions of porins tends to be quite different among S. typhimurium OmpF, OmpC, and OmpD porins. Immunological cross-reaction showed that S. typhimurium OmpD was very closely related to Escherichia coli NmpC and to the Lc porin of bacteriophage PA-2. Immunologically, E. coli OmpG and protein K also appear to belong to the family of closely related porins including E. coli OmpF, OmpC, PhoE, and NmpC and S. typhimurium OmpF, OmpC, and OmpD. It appears, however, that S. typhimurium "PhoE" is not closely related to this group. Finally, about one-third of the MAbs that presumably recognize buried epitopes reacted with porin domains that are widely conserved in 13 species of the family Enterobacteriaceae, but apparently not in the seven nonenterobacterial species tested. These data are evaluated in relation to host immune response to infection by gram-negative bacteria.
Collapse
Affiliation(s)
- S P Singh
- Biomedical Research Program, Alabama State University, Montgomery 36101-0271
| | | | | | | | | |
Collapse
|
34
|
Papaioannou S, Marsh PD, Ivanyi L. The immunogenicity of outer membrane proteins of haemin-depleted Porphyromonas (Bacteroides) gingivalis W50 in periodontal disease. ORAL MICROBIOLOGY AND IMMUNOLOGY 1991; 6:327-31. [PMID: 1668247 DOI: 10.1111/j.1399-302x.1991.tb00503.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The antigens from outer membrane protein extracts of Porphyromonas gingivalis (W50), grown under different haemin concentrations, were examined for binding with serum antibodies from patients with severe progressive periodontitis or from periodontally healthy control subjects. P. gingivalis was grown under haemin limitation (0.33 micrograms/ml) and haemin excess (2.5 micrograms/ml) conditions in a chemostat at a mean generation time of 6.9 h, at pH 7.5. Sarkosyl-insoluble fractions of outer membrane proteins from P. gingivalis were prepared, and analysed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblot techniques. The SDS-PAGE analysis of the outer membrane of haemin-limited P. gingivalis identified several new protein components, or changed expression of bands compared with cells grown under haemin excess. Immunoblot analysis showed IgG antibodies to 2 haemin deprivation-induced proteins in patients with severe progressive periodontitis, but not in the control sera. These results confirm the immunogenicity of some of the haemin-regulated outer membrane proteins of P. gingivalis in severe progressive periodontitis.
Collapse
|
35
|
Rutz JM, Abdullah T, Singh SP, Kalve VI, Klebba PE. Evolution of the ferric enterobactin receptor in gram-negative bacteria. J Bacteriol 1991; 173:5964-74. [PMID: 1717434 PMCID: PMC208340 DOI: 10.1128/jb.173.19.5964-5974.1991] [Citation(s) in RCA: 76] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Using sodium dodecyl sulfate-polyacrylamide gel electrophoresis of iron-deficient and replete cell envelopes, 59Fe-siderophore uptake studies, and Western immunoblots and cytofluorimetric analyses with monoclonal antibodies (MAbs), we surveyed a panel of gram-negative bacteria to identify outer membrane proteins that are structurally related to the Escherichia coli K-12 ferric enterobactin receptor, FepA. Antibodies within the panel identified FepA epitopes that are conserved among the majority of the bacteria tested, as well as epitopes present in only a few of the strains. In general, epitopes of FepA that are buried in the outer membrane bilayer were more conserved among gram-negative bacteria than epitopes that are exposed on the bacterial cell surface. The surface topology and tertiary structure of FepA are quite similar in E. coli and Shigella flexneri but differ in Salmonella typhimurium. Of the 18 different genera tested, 94% of the bacteria transported ferric enterobactin, including members of the previously unrecognized genera Citrobacter, Edwardsiella, Enterobacter, Haemophilus, Hafnia, Morganella, Neisseria, Proteus, Providencia, Serratia, and Yersinia. The ferric enterobactin receptor contains at least one buried epitope, recognized by MAb 2 (C. K. Murphy, V. I. Kalve, and P. E. Klebba, J. Bacteriol. 172:2736-2746, 1990), that is conserved within the structure of an iron-regulated cell envelope protein in all the bacteria that we have surveyed. With MAb 2, we identified and determined the Mr of cell envelope antigens that are immunologically related to E. coli FepA in all the gram-negative bacteria tested. Collectively, the library of anti-FepA MAbs showed unique patterns of reactivity with the different bacteria, allowing identification and discrimination of species within the following gram-negative genera: Aeromonas, Citrobacter, Edwardsiella, Enterobacter, Escherichia, Haemophilus, Hafnia, Klebsiella, Morganella, Neisseria, Proteus, Providencia, Pseudomonas, Salmonella, Serratia, Shigella, Vibrio, and Yersinia.
Collapse
Affiliation(s)
- J M Rutz
- Department of Microbiology, Medical College of Wisconsin, Milwaukee 53226
| | | | | | | | | |
Collapse
|
36
|
Chen CK, DeNardin A, Dyer DW, Genco RJ, Neiders ME. Human immunoglobulin G antibody response to iron-repressible and other membrane proteins of Porphyromonas (Bacteroides) gingivalis. Infect Immun 1991; 59:2427-33. [PMID: 2050407 PMCID: PMC258028 DOI: 10.1128/iai.59.7.2427-2433.1991] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The human immunoglobulin G (IgG) immune response against Porphyromonas (Bacteroides) gingivalis A7A1-28 iron-repressible membrane proteins (IRMPs) and other membrane proteins was examined by immunoblot analysis. Thirty sera from patients with adult periodontitis and 30 sera from periodontally healthy subjects were included. Iron limitation of P. gingivalis was achieved by growing bacteria in brain heart infusion broth supplemented with protoporphyrin IX and 250 microM alpha, alpha'-dypyridyl, a ferrous iron chelator. Iron-sufficient growth was achieved by growing bacteria in the same medium without alpha, alpha'-dypyridyl. Human sera, in particular those from patients with periodontitis who exhibited high levels of IgG against whole cells of P. gingivalis A7A1-28 in serum in an enzyme-linked immunosorbent assay (ELISA), commonly reacted with five membrane proteins with apparent molecular masses of 80, 67.5, 51, 40.5, and 28 kDa and four IRMPs of 46, 43, 37.5, and 22 kDa. More than 80% of the sera from patients with periodontitis and high levels of IgG against strain A7A1-28 in serum by ELISA reacted with the 46-, 43-, and 37.5-kDa IRMPs, and 40% of these subjects expressed immunoreactivity against the 22-kDa IRMP. Sera from patients with periodontitis and low levels of IgG against strain A7A1-28 in serum by ELISA and sera from periodontally healthy subjects exhibited less immunoreactivity against IRMPs and the five membrane proteins of P. gingivalis. The present study indicates that P. gingivalis IRMPs are immunogenic and that these proteins are expressed in vivo.
Collapse
Affiliation(s)
- C K Chen
- Department of Oral Biology, State University of New York, Buffalo 14214
| | | | | | | | | |
Collapse
|
37
|
Abstract
Iron is now recognized as playing a vital role in infection. Not only does it restricted availability in tissue fluids present microbial pathogens with the problem of acquiring sufficient for multiplication in vivo, but it also constitutes a major environmental signal which co-ordinately regulates the expression of a number of virulence and metabolic genes. Progress in understanding the strategies used by pathogens for acquiring iron in vivo, and their responses to iron restriction, is providing a fresh insight into microbial pathogenicity.
Collapse
Affiliation(s)
- E Griffiths
- National Institute for Biological Standards and Control, Potters Bar, Hertfordshire, UK
| |
Collapse
|
38
|
|
39
|
Armstrong S, Francis C, McIntosh M. Molecular analysis of the Escherichia coli ferric enterobactin receptor FepA. J Biol Chem 1990. [DOI: 10.1016/s0021-9258(18)77336-5] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
|
40
|
Faundez G, Aron L, Cabello FC. Chromosomal DNA, iron-transport systems, outer membrane proteins, and enterotoxin (heat labile) production in Salmonella typhi strains. J Clin Microbiol 1990; 28:894-7. [PMID: 1972158 PMCID: PMC267832 DOI: 10.1128/jcm.28.5.894-897.1990] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
We examined a representative collection of Salmonella typhi strains from Chile, Peru, Mexico, India, and England for the presence of several properties. All strains had a conserved pattern of outer membrane proteins, as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The electrophoresis profiles of chromosomal DNA digested with EcoRI and PstI restriction enzymes were similar for all the strains. A conserved pattern of hybridization was observed when digested chromosomal DNA was hybridized with DNA probes for the 36-kilodalton porin, enterobactin synthesis, and enterobactin receptor genes. All the strains produced enterobactin but not aerobactin in bioassays. None of the strains produced heat-labile toxin, as measured by an enzyme-linked immunosorbent assay. Colony and Southern hybridizations with DNA probes for aerobactin synthesis and its receptor and heat-labile toxin genes were negative. These results indicate that S. typhi strains from different origins have similar phenotypic and genetic properties and, as has been suggested, constitute a clone.
Collapse
Affiliation(s)
- G Faundez
- Department of Microbiology and Immunology, New York Medical College, Valhalla 10595
| | | | | |
Collapse
|