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Saggese A, Baccigalupi L, Donadio G, Ricca E, Isticato R. The Bacterial Spore as a Mucosal Vaccine Delivery System. Int J Mol Sci 2023; 24:10880. [PMID: 37446054 DOI: 10.3390/ijms241310880] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Revised: 06/27/2023] [Accepted: 06/28/2023] [Indexed: 07/15/2023] Open
Abstract
The development of efficient mucosal vaccines is strongly dependent on the use of appropriate vectors. Various biological systems or synthetic nanoparticles have been proposed to display and deliver antigens to mucosal surfaces. The Bacillus spore, a metabolically quiescent and extremely resistant cell, has also been proposed as a mucosal vaccine delivery system and shown able to conjugate the advantages of live and synthetic systems. Several antigens have been displayed on the spore by either recombinant or non-recombinant approaches, and antigen-specific immune responses have been observed in animals immunized by the oral or nasal route. Here we review the use of the bacterial spore as a mucosal vaccine vehicle focusing on the advantages and drawbacks of using the spore and of the recombinant vs. non-recombinant approach to display antigens on the spore surface. An overview of the immune responses induced by antigen-displaying spores so far tested in animals is presented and discussed.
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Affiliation(s)
- Anella Saggese
- Department of Biology, Federico II University, 80126 Naples, Italy
| | - Loredana Baccigalupi
- Department of Molecular Medicine and Medical Biotechnology, Federico II University, 80131 Naples, Italy
| | - Giuliana Donadio
- Department of Pharmacy, University of Salerno, 84084 Salerno, Italy
| | - Ezio Ricca
- Department of Biology, Federico II University, 80126 Naples, Italy
| | - Rachele Isticato
- Department of Biology, Federico II University, 80126 Naples, Italy
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2
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Isticato R. Bacterial Spore-Based Delivery System: 20 Years of a Versatile Approach for Innovative Vaccines. Biomolecules 2023; 13:947. [PMID: 37371527 DOI: 10.3390/biom13060947] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Revised: 05/25/2023] [Accepted: 06/03/2023] [Indexed: 06/29/2023] Open
Abstract
Mucosal vaccines offer several advantages over injectable conventional vaccines, such as the induction of adaptive immunity, with secretory IgA production at the entry site of most pathogens, and needle-less vaccinations. Despite their potential, only a few mucosal vaccines are currently used. Developing new effective mucosal vaccines strongly relies on identifying innovative antigens, efficient adjuvants, and delivery systems. Several approaches based on phages, bacteria, or nanoparticles have been proposed to deliver antigens to mucosal surfaces. Bacterial spores have also been considered antigen vehicles, and various antigens have been successfully exposed on their surface. Due to their peculiar structure, spores conjugate the advantages of live microorganisms with synthetic nanoparticles. When mucosally administered, spores expressing antigens have been shown to induce antigen-specific, protective immune responses. This review accounts for recent progress in the formulation of spore-based mucosal vaccines, describing a spore's structure, specifically the spore surface, and the diverse approaches developed to improve its efficiency as a vehicle for heterologous antigen presentation.
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Affiliation(s)
- Rachele Isticato
- Department of Biology, University of Naples Federico II, Complesso Universitario Monte S. Angelo, Via Cinthia 4, 80126 Naples, Italy
- Interuniversity Center for Studies on Bioinspired Agro-Environmental Technology (BAT Center), 80055 Naples, Italy
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3
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Vetráková A, Chovanová RK, Rechtoríková R, Krajčíková D, Barák I. Bacillus subtilis spores displaying RBD domain of SARS-CoV-2 spike protein. Comput Struct Biotechnol J 2023; 21:1550-1556. [PMID: 36778063 PMCID: PMC9904849 DOI: 10.1016/j.csbj.2023.02.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Revised: 01/16/2023] [Accepted: 02/04/2023] [Indexed: 02/10/2023] Open
Abstract
Bacillus subtilis spores are considered to be efficient and useful vehicles for the surface display and delivery of heterologous proteins. In this study, we prepared recombinant spores with the receptor binding domain (RBD) of the SARS-CoV-2 spike glycoprotein displayed on their surface in fusion with the CotZ or CotY spore coat proteins as a possible tool for the development of an oral vaccine against the SARS-CoV-2 virus. The RBD was attached to the N-terminus or C-terminus of the coat proteins. We also directly adsorbed non-recombinantly produced RBD to the spore surface. SDS-PAGE, western blot and fluorescence microscopy were used to analyze RBD surface expression on purified spores. Results obtained from both display systems, recombinant and non-recombinant, demonstrated that RBD was present on the spore surfaces.
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4
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Peng F, Xiang Y, Wang H, Hu Y, Zhou R, Hu Y. Biomimetic Assembly of Spore@ZIF-8 Microspheres for Vaccination. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2022; 18:e2204011. [PMID: 35996807 DOI: 10.1002/smll.202204011] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Indexed: 06/15/2023]
Abstract
Vaccines have been one of the most powerful weapons to defend against infectious diseases for a long time now. Subunit vaccines are of increasing importance because of their safety and effectiveness. In this work, a Bacillus amyloliquefaciens spore@zeolitic imidazolate framework-8 (ZIF-8) vaccine platform is constructed. The ovalbumin (OVA) is encapsulated in the ZIF-8 shells as a model antigen to form a spore@OVA@ZIF-8 (SOZ) composite. The assembly of ZIF-8 improves the loading content of OVA on the spores and provides OVA with long-term protection. The SOZ composite enhances the immunization efficacy in multiple ways, such as facilitation of antigen uptake and lysosome escape, stimulation of dendritic cells to mature and secrete cytokines, boosting of antibody production and formation of an antigen depot. This platform shows several advantages including easy preparation, cost-effectiveness, long life, convenience of transportation and storage, and no need for the cold chain. These findings may have promising implications for the rational design of safe and effective spore-based composite vaccine platforms.
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Affiliation(s)
- Fei Peng
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, China
- College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
- Hongshan Laboratory, Wuhan, Hubei Province, 430070, China
| | - Yuqiang Xiang
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, China
- College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
- Hongshan Laboratory, Wuhan, Hubei Province, 430070, China
| | - Hui Wang
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, China
- College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
- Hongshan Laboratory, Wuhan, Hubei Province, 430070, China
| | - Yanjie Hu
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, China
- College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
- Hongshan Laboratory, Wuhan, Hubei Province, 430070, China
| | - Rui Zhou
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, China
- Hongshan Laboratory, Wuhan, Hubei Province, 430070, China
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, China
- International Research Center for Animal Diseases (Ministry of Science & Technology of China), Wuhan, 430070, China
- Cooperative Innovation Center of Sustainable Pig Production, Wuhan, 430070, China
| | - Yonggang Hu
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, China
- College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
- Hongshan Laboratory, Wuhan, Hubei Province, 430070, China
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5
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Bacillus subtilis spores as delivery system for nasal Plasmodium falciparum circumsporozoite surface protein immunization in a murine model. Sci Rep 2022; 12:1531. [PMID: 35087102 PMCID: PMC8795416 DOI: 10.1038/s41598-022-05344-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Accepted: 11/29/2021] [Indexed: 11/15/2022] Open
Abstract
Malaria remains a widespread public health problem in tropical and subtropical regions around the world, and there is still no vaccine available for full protection. In recent years, it has been observed that spores of Bacillus subtillis can act as a vaccine carrier and adjuvant, promoting an elevated humoral response after co-administration with antigens either coupled or integrated to their surface. In our study, B. subtillis spores from the KO7 strain were used to couple the recombinant CSP protein of P. falciparum (rPfCSP), and the nasal humoral-induced immune response in Balb/C mice was evaluated. Our results demonstrate that the spores coupled to rPfCSP increase the immunogenicity of the antigen, which induces high levels of serum IgG, and with balanced Th1/Th2 immune response, being detected antibodies in serum samples for 250 days. Therefore, the use of B. subtilis spores appears to be promising for use as an adjuvant in a vaccine formulation.
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Protective Immunity Against Enterotoxigenic Escherichia coli by Oral Vaccination of Engineered Lactococcus lactis. Curr Microbiol 2021; 78:3464-3473. [PMID: 34264362 PMCID: PMC8280578 DOI: 10.1007/s00284-021-02601-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2020] [Accepted: 04/13/2021] [Indexed: 02/07/2023]
Abstract
Enterotoxigenic Escherichia coli (ETEC) is one of the leading causes of diarrhea in children globally, and thus suitable vaccines are desired. Antigen display on lactic acid bacteria is a reliable approach for efficient oral vaccination and preventing bowel diseases. To develop an oral vaccine against ETEC, the gene of the binding domain from heat-labile toxin (LTB), a key ETEC virulence factor, was codon-optimized and cloned into a construct containing a signal peptide and an anchor for display on L. lactis. Bioinformatics analysis showed a codon adaptation index of 0.95 for the codon-optimized gene. Cell surface expression of LTB was confirmed by transmission electron microscopy and blotting. White New Zealand rabbits were immunized per os (PO) with the recombinant L. lactis, and the antibody titers were assayed with ELISA. In vitro neutralization assay was performed using mouse adrenal tumor cells and rabbit ileal loop test was performed as the in vivo assay. ELISA results indicated that oral administration of the engineered L. lactis elicited a significant production of IgA in the intestine. In vitro neutralization assay showed that the effect of the toxin could be neutralized with 500 µg/ml of IgG isolated from the oral vaccine group. Furthermore, the dose of ETEC causing fluid accumulation in the ileal loop test showed a tenfold increase in rabbits immunized with either recombinant L. lactis or LTB protein compared to other groups. Our results imply that recombinant L. lactis could potentially be an effective live oral vaccine against ETEC toxicity.
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Ricca E, Baccigalupi L, Isticato R. Spore-adsorption: Mechanism and applications of a non-recombinant display system. Biotechnol Adv 2020; 47:107693. [PMID: 33387640 DOI: 10.1016/j.biotechadv.2020.107693] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 12/22/2020] [Accepted: 12/23/2020] [Indexed: 12/18/2022]
Abstract
Surface display systems have been developed to express target molecules on almost all types of biological entities from viruses to mammalian cells and on a variety of synthetic particles. Various approaches have been developed to achieve the display of many different target molecules, aiming at several technological and biomedical applications. Screening of libraries, delivery of drugs or antigens, bio-catalysis, sensing of pollutants and bioremediation are commonly considered as fields of potential application for surface display systems. In this review, the non-recombinant approach to display antigens and enzymes on the surface of bacterial spores is discussed. Examples of molecules displayed on the spore surface and their potential applications are summarized and a mechanism of display is proposed.
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Affiliation(s)
- Ezio Ricca
- Department of Biology, Federico II University of Naples, Italy.
| | - Loredana Baccigalupi
- Department of Molecular Medicine and Medical Biotechnology, Federico II University of Naples, Italy
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8
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Maubrigades LR, Santos FDS, Gonçalves VS, Rodrigues PRC, Leite FPL. Association of Bacillus toyonensis spores with alum improves bovine herpesvirus 5 subunit vaccine immune response in mice. Vaccine 2020; 38:8216-8223. [PMID: 33172696 DOI: 10.1016/j.vaccine.2020.10.066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Revised: 10/14/2020] [Accepted: 10/17/2020] [Indexed: 10/23/2022]
Abstract
Spores of the genus Bacillus are molecules capable of increasing the vaccine adjuvanticity. Bovine herpesvirus type 5 (BoHV-5) is responsible for meningoencephalitis that causes important economic losses in cattle. BoHV-5 glycoprotein D (gD) is a target of vaccine antigen and plays an important role in host cell penetration. The present study aimed to evaluate the adjuvanticity of Bacillus toyonensis (B.t) spores, live and heat-killed, associated with a vaccine formulated with aluminum hydroxide (alum) and the recombinant BoHV-5 glycoprotein D (rgD) in an experimental murine model. Six experimental groups of mice were subcutaneously vaccinated on day 0 and received a booster on day 21 of the experiment, with the following vaccine formulations: rgD (40 µg) + live spores (2 × 109 CFU); rgD + killed spores; rgD + live spores + alum (2.0 mg); rgD + killed spores + alum; rgD + alum, and rgD + PBS. Mice from rgD + live spores group showed an increase in rgD IgG titers from the 21st day until the end of the experiment. The groups of live and killed spores, associated to alum, had similar levels of IgG titers with no significant difference between each other; however, by the 14th and 28th day until the end of the experiment, presented higher IgG titers in comparison to the rgD + alum group. Moreover, increased serum levels of IgG1, IgG2a, and IgG2b were detected in mice that received spores in the vaccine formulation. The spores associated with alum groups showed neutralizing BoHV-5 antibodies and high mRNA transcription of the cytokines IFN-γ (66-fold), IL-17 (14-fold), and IL-12 (2.8-fold). In conclusion, our data demonstrated that the B. toyonensis spores, live or killed, associated with alum increased the adjuvanticity for BoHV-5 rgD in mice, suggesting the use of B. toyonensis spores as a promising component for vaccine formulations.
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Affiliation(s)
- Lucas Reichert Maubrigades
- Programa de Pós-Graduação em Biotecnologia, Centro de Desenvolvimento Tecnológico, Núcleo de Biotecnologia, Universidade Federal de Pelotas, 96160-900 Capão do Leão, RS, Brazil
| | - Francisco Denis Souza Santos
- Programa de Pós-Graduação em Biotecnologia, Centro de Desenvolvimento Tecnológico, Núcleo de Biotecnologia, Universidade Federal de Pelotas, 96160-900 Capão do Leão, RS, Brazil
| | - Vitória Sequeira Gonçalves
- Programa de Pós-Graduação em Biotecnologia, Centro de Desenvolvimento Tecnológico, Núcleo de Biotecnologia, Universidade Federal de Pelotas, 96160-900 Capão do Leão, RS, Brazil
| | - Paulo Ricardo Centeno Rodrigues
- Programa de Pós-Graduação em Veterinária, Faculdade de Veterinária, Universidade Federal de Pelotas, 96160-900 Capão do Leão, RS, Brazil
| | - Fábio Pereira Leivas Leite
- Programa de Pós-Graduação em Biotecnologia, Centro de Desenvolvimento Tecnológico, Núcleo de Biotecnologia, Universidade Federal de Pelotas, 96160-900 Capão do Leão, RS, Brazil; Programa de Pós-Graduação em Veterinária, Faculdade de Veterinária, Universidade Federal de Pelotas, 96160-900 Capão do Leão, RS, Brazil.
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9
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Petrillo C, Castaldi S, Lanzilli M, Saggese A, Donadio G, Baccigalupi L, Ricca E, Isticato R. The temperature of growth and sporulation modulates the efficiency of spore-display in Bacillus subtilis. Microb Cell Fact 2020; 19:185. [PMID: 33004043 PMCID: PMC7528486 DOI: 10.1186/s12934-020-01446-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Accepted: 09/25/2020] [Indexed: 02/04/2023] Open
Abstract
BACKGROUND Bacterial spores displaying heterologous antigens or enzymes have long been proposed as mucosal vaccines, functionalized probiotics or biocatalysts. Two main strategies have been developed to display heterologous molecules on the surface of Bacillus subtilis spores: (i) a recombinant approach, based on the construction of a gene fusion between a gene coding for a coat protein (carrier) and DNA coding for the protein to be displayed, and (ii) a non-recombinant approach, based on the spontaneous and stable adsorption of heterologous molecules on the spore surface. Both systems have advantages and drawbacks and the selection of one or the other depends on the protein to be displayed and on the final use of the activated spore. It has been recently shown that B. subtilis builds structurally and functionally different spores when grown at different temperatures; based on this finding B. subtilis spores prepared at 25, 37 or 42 °C were compared for their efficiency in displaying various model proteins by either the recombinant or the non-recombinant approach. RESULTS Immune- and fluorescence-based assays were used to analyze the display of several model proteins on spores prepared at 25, 37 or 42 °C. Recombinant spores displayed different amounts of the same fusion protein in response to the temperature of spore production. In spores simultaneously displaying two fusion proteins, each of them was differentially displayed at the various temperatures. The display by the non-recombinant approach was only modestly affected by the temperature of spore production, with spores prepared at 37 or 42 °C slightly more efficient than 25 °C spores in adsorbing at least some of the model proteins tested. CONCLUSION Our results indicate that the temperature of spore production allows control of the display of heterologous proteins on spores and, therefore, that the spore-display strategy can be optimized for the specific final use of the activated spores by selecting the display approach, the carrier protein and the temperature of spore production.
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Affiliation(s)
- Claudia Petrillo
- Department of Biology, Federico II University complesso universitario di Monte Sant' Angelo via Cinthia, 80126, Napoli, Italy
| | - Stefany Castaldi
- Department of Biology, Federico II University complesso universitario di Monte Sant' Angelo via Cinthia, 80126, Napoli, Italy
| | - Mariamichela Lanzilli
- Department of Biology, Federico II University complesso universitario di Monte Sant' Angelo via Cinthia, 80126, Napoli, Italy
- Institute of Biomolecular Chemistry, National Research Council of Italy, Pozzuoli (Naples), Italy
| | - Anella Saggese
- Department of Biology, Federico II University complesso universitario di Monte Sant' Angelo via Cinthia, 80126, Napoli, Italy
| | - Giuliana Donadio
- Department of Biology, Federico II University complesso universitario di Monte Sant' Angelo via Cinthia, 80126, Napoli, Italy
- Department of Medicine, Surgery and Dentistry "Scuola Medica Salernitana", University of Salerno, Fisciano (SA), Italy
| | - Loredana Baccigalupi
- Department of Molecular Medicine and Medical Biotechnology, Federico II University of Naples, Napoli, Italy
| | - Ezio Ricca
- Department of Biology, Federico II University complesso universitario di Monte Sant' Angelo via Cinthia, 80126, Napoli, Italy.
| | - Rachele Isticato
- Department of Biology, Federico II University complesso universitario di Monte Sant' Angelo via Cinthia, 80126, Napoli, Italy
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Santos FDS, Mazzoli A, Maia AR, Saggese A, Isticato R, Leite F, Iossa S, Ricca E, Baccigalupi L. A probiotic treatment increases the immune response induced by the nasal delivery of spore-adsorbed TTFC. Microb Cell Fact 2020; 19:42. [PMID: 32075660 PMCID: PMC7029466 DOI: 10.1186/s12934-020-01308-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Accepted: 02/12/2020] [Indexed: 12/21/2022] Open
Abstract
Background Spore-forming bacteria of the Bacillus genus are widely used probiotics known to exert their beneficial effects also through the stimulation of the host immune response. The oral delivery of B. toyonensis spores has been shown to improve the immune response to a parenterally administered viral antigen in mice, suggesting that probiotics may increase the efficiency of systemic vaccines. We used the C fragment of the tetanus toxin (TTFC) as a model antigen to evaluate whether a treatment with B. toyonensis spores affected the immune response to a mucosal antigen. Results Purified TTFC was given to mice by the nasal route either as a free protein or adsorbed to B. subtilis spores, a mucosal vaccine delivery system proved effective with several antigens, including TTFC. Spore adsorption was extremely efficient and TTFC was shown to be exposed on the spore surface. Spore-adsorbed TTFC was more efficient than the free antigen in inducing an immune response and the probiotic treatment improved the response, increasing the production of TTFC-specific secretory immunoglobin A (sIgA) and causing a faster production of serum IgG. The analysis of the induced cytokines indicated that also the cellular immune response was increased by the probiotic treatment. A 16S RNA-based analysis of the gut microbial composition did not show dramatic differences due to the probiotic treatment. However, the abundance of members of the Ruminiclostridium 6 genus was found to correlate with the increased immune response of animals immunized with the spore-adsorbed antigen and treated with the probiotic. Conclusion Our results indicate that B. toyonensis spores significantly contribute to the humoral and cellular responses elicited by a mucosal immunization with spore-adsorbed TTFC, pointing to the probiotic treatment as an alternative to the use of adjuvants for mucosal vaccinations.
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Affiliation(s)
- Francisco Denis S Santos
- Dipartimento di Biologia, Università di Napoli Federico II, Naples, Italy.,Centro de Desenvolvimento Tecnológico, Núcleo de Biotecnologia, Universidade Federal de Pelotas, Pelotas, Brazil
| | - Arianna Mazzoli
- Dipartimento di Biologia, Università di Napoli Federico II, Naples, Italy
| | - Ana Raquel Maia
- Dipartimento di Biologia, Università di Napoli Federico II, Naples, Italy
| | - Anella Saggese
- Dipartimento di Biologia, Università di Napoli Federico II, Naples, Italy
| | - Rachele Isticato
- Dipartimento di Biologia, Università di Napoli Federico II, Naples, Italy
| | - Fabio Leite
- Centro de Desenvolvimento Tecnológico, Núcleo de Biotecnologia, Universidade Federal de Pelotas, Pelotas, Brazil
| | - Susanna Iossa
- Dipartimento di Biologia, Università di Napoli Federico II, Naples, Italy
| | - Ezio Ricca
- Dipartimento di Biologia, Università di Napoli Federico II, Naples, Italy.
| | - Loredana Baccigalupi
- Dipartimento di Medicina Molecolare e Biotecnologie Mediche, Università di Napoli Federico II, Naples, Italy
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11
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Induction of a Specific Humoral Immune Response by Nasal Delivery of Bcla2 ctd of Clostridioides difficile. Int J Mol Sci 2020; 21:ijms21041277. [PMID: 32074955 PMCID: PMC7072882 DOI: 10.3390/ijms21041277] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Revised: 01/21/2020] [Accepted: 02/10/2020] [Indexed: 12/18/2022] Open
Abstract
Clostridioides difficile, formerly known as Clostridium difficile, is a spore-forming bacterium considered as the most common cause of nosocomial infections in developed countries. The spore of C. difficile is involved in the transmission of the pathogen and in its first interaction with the host; therefore, a therapeutic approach able to control C. difficile spores would improve the clearance of the infection. The C-terminal (CTD) end of BclA2, a spore surface protein of C. difficile responsible of the interaction with the host intestinal cells, was selected as a putative mucosal antigen. The BclA2 fragment, BclA2CTD, was purified and used to nasally immunize mice both as a free protein and after adsorption to the spore of Bacillus subtilis, a well-established mucosal delivery vehicle. While the adsorption to spores increased the in vitro stability of BclA2CTD, in vivo both free and spore-adsorbed BclA2CTD were able to induce a similar, specific humoral immune response in a murine model. Although in the experimental conditions utilized the immune response was not protective, the induction of specific IgG indicates that free or spore-bound BclA2CTD could act as a putative mucosal antigen targeting C. difficile spores.
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12
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Mohamed MYH, Christie G. A system for the expression and release of heterologous proteins from the core ofBacillus subtilisspores. FEMS Microbiol Lett 2018; 365:5195517. [DOI: 10.1093/femsle/fny270] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Accepted: 11/20/2018] [Indexed: 12/15/2022] Open
Affiliation(s)
- Mohamed Y H Mohamed
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge CB3 0AS, UK
| | - Graham Christie
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge CB3 0AS, UK
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13
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Mingmongkolchai S, Panbangred W. Bacillus probiotics: an alternative to antibiotics for livestock production. J Appl Microbiol 2018; 124:1334-1346. [PMID: 29316021 DOI: 10.1111/jam.13690] [Citation(s) in RCA: 173] [Impact Index Per Article: 28.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Revised: 12/16/2017] [Accepted: 12/29/2017] [Indexed: 12/16/2022]
Abstract
The use of probiotics as feed supplements in animal production has increased considerably over the last decade, particularly since the ban on antibiotic growth promoters in the livestock sector. Several Bacillus sp. are attractive for use as probiotic supplements in animal feed due to their ability to produce spores. Their heat stability and ability to survive the low pH of the gastric barrier represent an advantage over other probiotic micro-organisms. This review discusses important characteristics required for selection of Bacillus probiotic strains and summarizes the beneficial effect of Bacillus-based feed additives on animal production. Although the mechanism of action of Bacillus probiotics has not been fully elucidated, they are effective in improving the growth, survival and health status of terrestrial and aquatic livestock. Bacillus strains also have utility in bioremediation and can reduce nitrogenous waste, thereby improving environmental conditions and water quality. Finally, recent innovative approaches for using Bacillus spores in various applications are discussed.
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Affiliation(s)
- S Mingmongkolchai
- Department of Biotechnology, Faculty of Science, Mahidol University, Bangkok, Thailand.,Faculty of Science, Mahidol University-Osaka University Collaborative Research Center for Bioscience and Biotechnology (MU-OU:CRC), Mahidol University, Bangkok, Thailand
| | - W Panbangred
- Department of Biotechnology, Faculty of Science, Mahidol University, Bangkok, Thailand.,Faculty of Science, Mahidol University-Osaka University Collaborative Research Center for Bioscience and Biotechnology (MU-OU:CRC), Mahidol University, Bangkok, Thailand
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14
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Petruk G, Donadio G, Lanzilli M, Isticato R, Monti DM. Alternative use of Bacillus subtilis spores: protection against environmental oxidative stress in human normal keratinocytes. Sci Rep 2018; 8:1745. [PMID: 29379084 PMCID: PMC5788939 DOI: 10.1038/s41598-018-20153-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Accepted: 01/15/2018] [Indexed: 12/25/2022] Open
Abstract
Inorganic trivalent arsenic is a major environmental pollutant and exposure to human results in many pathologies, including keratosis and carcinoma. Here, we analyzed the effects of B. subtilis spores on human normal keratinocytes in the presence of sodium arsenite oxidative stress. Pre-treatment of cells with spores before inducing oxidative stress was able to keep normal levels of intracellular ROS, GSH and lipid peroxidation, as well as to inhibit the activation of the MAPK cascade. Moreover, spores showed a positive effect on cell proliferation, probably due to their binding on the cell surface and the activation of intracellular catalases. We found that spores exert their protective effect by the nuclear translocation of Nrf-2, involved in the activation of stress response genes. This, in turn, resulted in a protective effect against sodium arsenite stress injury, as oxidative stress markers were reported to physiological levels when cells were stressed before incubating them with spores. Therefore, B. subtilis spores can be considered as a new agent to counteract oxidative stress on normal human keratinocytes.
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Affiliation(s)
- Ganna Petruk
- Department of Chemical Sciences, University of Naples Federico II, Complesso Universitario Monte Sant'Angelo, via Cinthia 4, 80126, Naples, Italy
| | - Giuliana Donadio
- Department of Biology, University of Naples Federico II, Complesso Universitario Monte Sant'Angelo, via Cinthia 4, 80126, Naples, Italy
| | - Mariamichela Lanzilli
- Department of Biology, University of Naples Federico II, Complesso Universitario Monte Sant'Angelo, via Cinthia 4, 80126, Naples, Italy
| | - Rachele Isticato
- Department of Biology, University of Naples Federico II, Complesso Universitario Monte Sant'Angelo, via Cinthia 4, 80126, Naples, Italy.
| | - Daria Maria Monti
- Department of Chemical Sciences, University of Naples Federico II, Complesso Universitario Monte Sant'Angelo, via Cinthia 4, 80126, Naples, Italy. .,Istituto Nazionale di Biostrutture e Biosistemi (INBB), Rome, Italy.
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15
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Mattossovich R, Iacono R, Cangiano G, Cobucci-Ponzano B, Isticato R, Moracci M, Ricca E. Conversion of xylan by recyclable spores of Bacillus subtilis displaying thermophilic enzymes. Microb Cell Fact 2017; 16:218. [PMID: 29183330 PMCID: PMC5706412 DOI: 10.1186/s12934-017-0833-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Accepted: 11/21/2017] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND The Bacillus subtilis spore has long been used to display antigens and enzymes. Spore display can be accomplished by a recombinant and a non-recombinant approach, with the latter proved more efficient than the recombinant one. We used the non-recombinant approach to independently adsorb two thermophilic enzymes, GH10-XA, an endo-1,4-β-xylanase (EC 3.2.1.8) from Alicyclobacillus acidocaldarius, and GH3-XT, a β-xylosidase (EC 3.2.1.37) from Thermotoga thermarum. These enzymes catalyze, respectively, the endohydrolysis of (1-4)-β-D-xylosidic linkages of xylans and the hydrolysis of (1-4)-β-D-xylans to remove successive D-xylose residues from the non-reducing termini. RESULTS We report that both purified enzymes were independently adsorbed on purified spores of B. subtilis. The adsorption was tight and both enzymes retained part of their specific activity. When spores displaying either GH10-XA or GH3-XT were mixed together, xylan was hydrolysed more efficiently than by a mixture of the two free, not spore-adsorbed, enzymes. The high total activity of the spore-bound enzymes is most likely due to a stabilization of the enzymes that, upon adsorption on the spore, remained active at the reaction conditions for longer than the free enzymes. Spore-adsorbed enzymes, collected after the two-step reaction and incubated with fresh substrate, were still active and able to continue xylan degradation. The recycling of the mixed spore-bound enzymes allowed a strong increase of xylan degradation. CONCLUSION Our results indicate that the two-step degradation of xylans can be accomplished by mixing spores displaying either one of two required enzymes. The two-step process occurs more efficiently than with the two un-adsorbed, free enzymes and adsorbed spores can be reused for at least one other reaction round. The efficiency of the process, the reusability of the adsorbed enzymes, and the well documented robustness of spores of B. subtilis indicate the spore as a suitable platform to display enzymes for single as well as multi-step reactions.
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Affiliation(s)
- Rosanna Mattossovich
- Department of Biology, Federico II University of Naples, Via Cinthia 4, 80126 Naples, MSA Italy
| | - Roberta Iacono
- Institute of Biosciences and BioResources, CNR, Naples, Italy
| | - Giuseppina Cangiano
- Department of Biology, Federico II University of Naples, Via Cinthia 4, 80126 Naples, MSA Italy
| | | | - Rachele Isticato
- Department of Biology, Federico II University of Naples, Via Cinthia 4, 80126 Naples, MSA Italy
| | - Marco Moracci
- Department of Biology, Federico II University of Naples, Via Cinthia 4, 80126 Naples, MSA Italy
- Institute of Biosciences and BioResources, CNR, Naples, Italy
| | - Ezio Ricca
- Department of Biology, Federico II University of Naples, Via Cinthia 4, 80126 Naples, MSA Italy
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16
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Potocki W, Negri A, Peszyńska-Sularz G, Hinc K, Obuchowski M, Iwanicki A. The combination of recombinant and non-recombinant Bacillus subtilis spore display technology for presentation of antigen and adjuvant on single spore. Microb Cell Fact 2017; 16:151. [PMID: 28899372 PMCID: PMC5596941 DOI: 10.1186/s12934-017-0765-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Accepted: 09/07/2017] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Bacillus subtilis spores can be used for presentation of heterologous proteins. Two main approaches have been developed, the recombinant one, requiring modification of bacterial genome to express a protein of interest as a fusion with spore-coat protein, and non-recombinant, based on the adsorption of a heterologous protein onto the spore. So far only single proteins have been displayed on the spore surface. RESULTS We have used a combined approach to adsorb and display FliD protein of Clostridium difficile on the surface of recombinant IL-2-presenting spores. Such spores presented FliD protein with efficiency comparable to FliD-adsorbed spores produced by wild-type 168 strain and elicited FliD-specific immune response in intranasally immunized mice. CONCLUSIONS Our results indicate that such dual display technology may be useful in creation of spores simultaneously presenting adjuvant and antigen molecules. Regarding the characteristics of elicited immune response it seems plausible that such recombinant IL-2-presenting spores with adsorbed FliD protein might be an interesting candidate for vaccine against infections with Clostridium difficile.
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Affiliation(s)
- Wojciech Potocki
- Department of Medical Biotechnology, Intercollegiate Faculty of Biotechnology UG-MUG, University of Gdańsk, Gdańsk, Poland
| | - Alessandro Negri
- Department of Medical Biotechnology, Intercollegiate Faculty of Biotechnology UG-MUG, University of Gdańsk, Gdańsk, Poland.,Department of Microbiology, Faculty of Biology, University of Gdańsk, Gdańsk, Poland
| | | | - Krzysztof Hinc
- Department of Medical Biotechnology, Intercollegiate Faculty of Biotechnology UG-MUG, Medical University of Gdańsk, Gdańsk, Poland
| | - Michał Obuchowski
- Department of Medical Biotechnology, Intercollegiate Faculty of Biotechnology UG-MUG, Medical University of Gdańsk, Gdańsk, Poland
| | - Adam Iwanicki
- Department of Medical Biotechnology, Intercollegiate Faculty of Biotechnology UG-MUG, Medical University of Gdańsk, Gdańsk, Poland.
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17
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Exploring the interaction network of the Bacillus subtilis outer coat and crust proteins. Microbiol Res 2017; 204:72-80. [PMID: 28870294 DOI: 10.1016/j.micres.2017.08.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Revised: 07/06/2017] [Accepted: 08/05/2017] [Indexed: 12/18/2022]
Abstract
Bacillus subtilis spores, representatives of an exceptionally resistant dormant cell type, are encircled by a thick proteinaceous layer called the spore coat. More than 80 proteins assemble into four distinct coat layers: a basement layer, an inner coat, an outer coat and a crust. As the spore develops inside the mother cell, spore coat proteins synthesized in the cytoplasm are gradually deposited onto the prespore surface. A small set of morphogenetic proteins necessary for spore coat morphogenesis are thought to form a scaffold to which the rest of the coat proteins are attached. Extensive localization and proteomic studies using wild type and mutant spores have revealed the arrangement of individual proteins within the spore coat layers. In this study we examined the interactions between the proteins localized to the outer coat and crust using a bacterial two hybrid system. These two layers are composed of at least 25 components. Self-interactions were observed for most proteins and numerous novel interactions were identified. The most interesting contacts are those made with the morphogenetic proteins CotE, CotY and CotZ; these could serve as a basis for understanding the specific roles of particular proteins in spore coat morphogenesis.
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18
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Wu Z, Tang Z, Shang M, Zhao L, Zhou L, Kong X, Lin Z, Sun H, Chen T, Xu J, Li X, Huang Y, Yu X. Comparative analysis of immune effects in mice model: Clonorchis sinensis cysteine protease generated from recombinant Escherichia coli and Bacillus subtilis spores. Parasitol Res 2017; 116:1811-1822. [PMID: 28502017 DOI: 10.1007/s00436-017-5445-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Accepted: 04/12/2017] [Indexed: 01/25/2023]
Abstract
Clonorchiasis remains a nonnegligible public health problem in endemic areas. Cysteine protease of Clonorchis sinensis (CsCP) plays indispensable roles in the parasitic physiology and pathology, and has been exploited as a promising drug and vaccine candidate. In recent years, development of spore-based vaccines against multiple pathogens has attracted many investigators' interest. In previous studies, the recombinant Escherichia coli (BL21) and Bacillus subtilis spores expressing CsCP have been successfully constructed, respectively. In this study, the immune effects of CsCP protein purified from recombinant BL21 (rCsCP) and B. subtilis spores presenting CsCP (B.s-CsCP) in Balb/c mice model were conducted with comparative analysis. Levels of specific IgG, IgG1 and IgG2a were significantly increased in sera from both rCsCP and B.s-CsCP intraperitoneally immunized mice. Additionally, recombinant spores expressing abundant fusion CsCP (0.03125 pg/spore) could strongly enhance the immunogenicity of CsCP with significantly higher levels of IgG and isotypes. Compared with rCsCP alone, intraperitoneal administration of mice with spores expressing CsCP achieved a better effect of fighting against C. sinensis infection by slowing down the process of fibrosis. Our results demonstrated that a combination of Th1/Th2 immune responses could be elicited by rCsCP, while spores displaying CsCP prominently induced Th1-biased specific immune responses, and the complex cytokine network maybe mediates protective immune responses against C. sinensis. This work further confirmed that the usage of B. subtilis spores displaying CsCP is an effective way to against C. sinensis.
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Affiliation(s)
- Zhanshuai Wu
- School of Life Sciences, Sun Yat-Sen University, Guangzhou, Guangdong, China
| | - Zeli Tang
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China.,Key Laboratory for Tropical Diseases Control, Sun Yat-sen University, Ministry of Education, Guangzhou, Guangdong, China.,Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, Guangdong, 510080, China
| | - Mei Shang
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China.,Key Laboratory for Tropical Diseases Control, Sun Yat-sen University, Ministry of Education, Guangzhou, Guangdong, China.,Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, Guangdong, 510080, China
| | - Lu Zhao
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China.,Key Laboratory for Tropical Diseases Control, Sun Yat-sen University, Ministry of Education, Guangzhou, Guangdong, China.,Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, Guangdong, 510080, China
| | - Lina Zhou
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China.,Key Laboratory for Tropical Diseases Control, Sun Yat-sen University, Ministry of Education, Guangzhou, Guangdong, China.,Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, Guangdong, 510080, China
| | - Xiangzhan Kong
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China.,Key Laboratory for Tropical Diseases Control, Sun Yat-sen University, Ministry of Education, Guangzhou, Guangdong, China.,Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, Guangdong, 510080, China
| | - Zhipeng Lin
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China.,Key Laboratory for Tropical Diseases Control, Sun Yat-sen University, Ministry of Education, Guangzhou, Guangdong, China.,Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, Guangdong, 510080, China
| | - Hengchang Sun
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China.,Key Laboratory for Tropical Diseases Control, Sun Yat-sen University, Ministry of Education, Guangzhou, Guangdong, China.,Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, Guangdong, 510080, China
| | - Tingjin Chen
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China.,Key Laboratory for Tropical Diseases Control, Sun Yat-sen University, Ministry of Education, Guangzhou, Guangdong, China.,Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, Guangdong, 510080, China
| | - Jin Xu
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China.,Key Laboratory for Tropical Diseases Control, Sun Yat-sen University, Ministry of Education, Guangzhou, Guangdong, China.,Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, Guangdong, 510080, China
| | - Xuerong Li
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China.,Key Laboratory for Tropical Diseases Control, Sun Yat-sen University, Ministry of Education, Guangzhou, Guangdong, China.,Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, Guangdong, 510080, China
| | - Yan Huang
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China. .,Key Laboratory for Tropical Diseases Control, Sun Yat-sen University, Ministry of Education, Guangzhou, Guangdong, China. .,Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, Guangdong, 510080, China.
| | - Xinbing Yu
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China. .,Key Laboratory for Tropical Diseases Control, Sun Yat-sen University, Ministry of Education, Guangzhou, Guangdong, China. .,Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, Guangdong, 510080, China.
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19
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Lanzilli M, Donadio G, Addevico R, Saggese A, Cangiano G, Baccigalupi L, Christie G, Ricca E, Isticato R. The Exosporium of Bacillus megaterium QM B1551 Is Permeable to the Red Fluorescence Protein of the Coral Discosoma sp. Front Microbiol 2016; 7:1752. [PMID: 27867376 PMCID: PMC5095127 DOI: 10.3389/fmicb.2016.01752] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Accepted: 10/19/2016] [Indexed: 11/17/2022] Open
Abstract
Bacterial spores spontaneously interact and tightly bind heterologous proteins. A variety of antigens and enzymes have been efficiently displayed on spores of Bacillus subtilis, the model system for spore formers. Adsorption on B. subtilis spores has then been proposed as a non-recombinant approach for the development of mucosal vaccine/drug delivery vehicles, biocatalysts, bioremediation, and diagnostic tools. We used spores of B. megaterium QM B1551 to evaluate their efficiency as an adsorption platform. Spores of B. megaterium are significantly larger than those of B. subtilis and of other Bacillus species and are surrounded by the exosporium, an outermost surface layer present only in some Bacillus species and lacking in B. subtilis. Strain QM B1551 of B. megaterium and a derivative strain totally lacking the exosporium were used to localize the adsorbed monomeric Red Fluorescent Protein (mRFP) of the coral Discosoma sp., used as a model heterologous protein. Our results indicate that spores of B. megaterium adsorb mRFP more efficiently than B. subtilis spores, that the exosporium is essential for mRFP adsorption, and that most of the adsorbed mRFP molecules are not exposed on the spore surface but rather localized in the space between the outer coat and the exosporium.
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Affiliation(s)
| | - Giuliana Donadio
- Department of Biology, University of Naples Federico II Naples, Italy
| | - Roberta Addevico
- Department of Biology, University of Naples Federico II Naples, Italy
| | - Anella Saggese
- Department of Biology, University of Naples Federico II Naples, Italy
| | | | | | - Graham Christie
- Department of Chemical Engineering and Biotechnology, University of Cambridge Cambridge, UK
| | - Ezio Ricca
- Department of Biology, University of Naples Federico II Naples, Italy
| | - Rachele Isticato
- Department of Biology, University of Naples Federico II Naples, Italy
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20
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Donadio G, Lanzilli M, Sirec T, Ricca E, Isticato R. Localization of a red fluorescence protein adsorbed on wild type and mutant spores of Bacillus subtilis. Microb Cell Fact 2016; 15:153. [PMID: 27609116 PMCID: PMC5016992 DOI: 10.1186/s12934-016-0551-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Accepted: 08/29/2016] [Indexed: 11/25/2022] Open
Abstract
BACKGROUND Bacterial spores have been proposed as vehicles to display heterologous proteins for the development of mucosal vaccines, biocatalysts, bioremediation and diagnostic tools. Two approaches have been developed to display proteins on the spore surface: a recombinant approach, based on the construction of gene fusions between DNA molecules coding for a spore surface protein (carrier) and for the heterologous protein to be displayed (passenger); and a non-recombinant approach based on spore adsorption, a spontaneous interaction between negatively charged, hydrophobic spores and purified proteins. The molecular details of spore adsorption have not been fully clarified yet. RESULTS We used the monomeric Red Fluorescent Protein (mRFP) of the coral Discosoma sp. and Bacillus subtilis spores of a wild type and an isogenic mutant strain lacking the CotH protein to clarify the adsorption process. Mutant spores, characterized by a strongly altered coat, were more efficient than wild type spores in adsorbing mRFP but the interaction was less stable and mRFP could be in part released by raising the pH of the spore suspension. A collection of isogenic strains carrying GFP fused to proteins restricted in different compartments of the B. subtilis spore was used to localize adsorbed mRFP molecules. In wild type spores mRFP infiltrated through crust and outer coat, localized in the inner coat and was not surface exposed. In mutant spores mRFP was present in all surface layers, inner, outer coat and crust and was exposed on the spore surface. CONCLUSIONS Our results indicate that different spores can be selected for different applications. Wild type spores are preferable when a very tight protein-spore interaction is needed, for example to develop reusable biocatalysts or bioremediation systems for field applications. cotH mutant spores are instead preferable when the heterologous protein has to be displayed on the spore surface or has to be released, as could be the case in mucosal delivery systems for antigens and drugs, respectively.
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Affiliation(s)
- Giuliana Donadio
- Department of Biology, Federico II University, via Cinthia-MSA, 80126 Naples, Italy
| | | | - Teja Sirec
- Department of Biology, Federico II University, via Cinthia-MSA, 80126 Naples, Italy
- School of Life Sciences, Gibbet Hill Campus, The University of Warwick, Coventry, CV4 7AL UK
| | - Ezio Ricca
- Department of Biology, Federico II University, via Cinthia-MSA, 80126 Naples, Italy
| | - Rachele Isticato
- Department of Biology, Federico II University, via Cinthia-MSA, 80126 Naples, Italy
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21
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Trovato M, Maurano F, D'Apice L, Costa V, Sartorius R, Cuccaro F, McBurney SP, Krebs SJ, Prisco A, Ciccodicola A, Rossi M, Haigwood NL, De Berardinis P. E2 multimeric scaffold for vaccine formulation: immune response by intranasal delivery and transcriptome profile of E2-pulsed dendritic cells. BMC Microbiol 2016; 16:152. [PMID: 27421762 PMCID: PMC4947308 DOI: 10.1186/s12866-016-0772-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Accepted: 07/12/2016] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND The E2 multimeric scaffold represents a powerful delivery system able to elicit robust humoral and cellular immune responses upon systemic administrations. Here recombinant E2 scaffold displaying the third variable loop of HIV-1 Envelope gp120 glycoprotein was administered via mucosa, and the mucosal and systemic immune responses were analysed. To gain further insights into the molecular mechanisms that orchestrate the immune response upon E2 vaccination, we analysed the transcriptome profile of dendritic cells (DCs) exposed to the E2 scaffold with the aim to define a specific gene expression signature for E2-primed immune responses. RESULTS The in vivo immunogenicity and the potential of E2 scaffold as a mucosal vaccine candidate were investigated in BALB/c mice vaccinated via the intranasal route. Fecal and systemic antigen-specific IgA antibodies, cytokine-producing CD4(+) and CD8(+) cells were induced assessing the immunogenicity of E2 particles via intranasal administration. The cytokine analysis identified a mixed T-helper cell response, while the systemic antibody response showed a prevalence of IgG1 isotype indicative of a polarized Th2-type immune response. RNA-Sequencing analysis revealed that E2 scaffold up-regulates in DCs transcriptional regulators of the Th2-polarizing cell response, defining a type 2 DC transcriptomic signature. CONCLUSIONS The current study provides experimental evidence to the possible application of E2 scaffold as antigen delivery system for mucosal immunization and taking advantages of genome-wide approach dissects the type of response induced by E2 particles.
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Affiliation(s)
- Maria Trovato
- Institute of Protein Biochemistry, C.N.R, Via Pietro Castellino 111, Naples, 80131, Italy
| | - Francesco Maurano
- Institute of Food Sciences, C.N.R, Via Roma 64, Avellino, 83100, Italy
| | - Luciana D'Apice
- Institute of Protein Biochemistry, C.N.R, Via Pietro Castellino 111, Naples, 80131, Italy
| | - Valerio Costa
- Institute of Genetics and Biophysics A. Buzzati-Traverso, C.N.R, Via Pietro Castellino 111, Naples, 80131, Italy
| | - Rossella Sartorius
- Institute of Protein Biochemistry, C.N.R, Via Pietro Castellino 111, Naples, 80131, Italy
| | - Fausta Cuccaro
- Institute of Protein Biochemistry, C.N.R, Via Pietro Castellino 111, Naples, 80131, Italy
| | - Sean P McBurney
- Division of Pathobiology and Immunology, Oregon National Primate Research Center, Oregon Health & Science University, 505 NW 185th Avenue, Beaverton, OR, 97006, USA
| | - Shelly J Krebs
- Division of Pathobiology and Immunology, Oregon National Primate Research Center, Oregon Health & Science University, 505 NW 185th Avenue, Beaverton, OR, 97006, USA
| | - Antonella Prisco
- Institute of Genetics and Biophysics A. Buzzati-Traverso, C.N.R, Via Pietro Castellino 111, Naples, 80131, Italy
| | - Alfredo Ciccodicola
- Institute of Genetics and Biophysics A. Buzzati-Traverso, C.N.R, Via Pietro Castellino 111, Naples, 80131, Italy.,Department of Science and Technology, University of Naples "Parthenope", Centro Direzionale Site island C4, Naples, 80143, Italy
| | - Mauro Rossi
- Institute of Food Sciences, C.N.R, Via Roma 64, Avellino, 83100, Italy
| | - Nancy L Haigwood
- Division of Pathobiology and Immunology, Oregon National Primate Research Center, Oregon Health & Science University, 505 NW 185th Avenue, Beaverton, OR, 97006, USA
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22
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Stasiłojć M, Hinc K, Peszyńska-Sularz G, Obuchowski M, Iwanicki A. Recombinant Bacillus subtilis Spores Elicit Th1/Th17-Polarized Immune Response in a Murine Model of Helicobacter pylori Vaccination. Mol Biotechnol 2016; 57:685-91. [PMID: 25779639 PMCID: PMC4503858 DOI: 10.1007/s12033-015-9859-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Current progress in research on vaccines against Helicobacter pylori emphasizes the significance of eliciting the Th1/Th17-polarized immune response. Such polarization can be achieved by selection of appropriate antigen and adjuvant. In this study, we wanted to check the polarization of the immune response elicited by UreB protein of Helicobacter acinonychis delivered by recombinant Bacillus subtilis spores upon oral immunization. B. subtilis spores presenting fragment of UreB protein and able to express entire UreB in vegetative cells after germination were orally administered to mice along with aluminum hydroxide or recombinant spores presenting IL-2 as an adjuvant. The pattern of cytokines secreted by sensitized splenocytes assessed by the cytometric bead array clearly indicated polarization of the immune response toward both Th1 and Th17 in mice immunized with the use of above-mentioned adjuvants. Obtained result is promising regarding the usage of recombinant spores in formulations of vaccines against H. pylori and line up with the current state of research emphasizing the key role of appropriate adjuvants.
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Affiliation(s)
- Małgorzata Stasiłojć
- Department of Medical Biotechnology, Intercollegiate Faculty of Biotechnology UG-MUG, University of Gdańsk, Dębinki 1, 80-211, Gdańsk, Poland
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23
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Wang H, Yang R, Hua X, Zhao W, Zhang W. Functional display of active β-galactosidase on Bacillus subtilis spores using crust proteins as carriers. Food Sci Biotechnol 2015. [DOI: 10.1007/s10068-015-0228-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
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24
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Isticato R, Sirec T, Vecchione S, Crispino A, Saggese A, Baccigalupi L, Notomista E, Driks A, Ricca E. The Direct Interaction between Two Morphogenetic Proteins Is Essential for Spore Coat Formation in Bacillus subtilis. PLoS One 2015; 10:e0141040. [PMID: 26484546 PMCID: PMC4618286 DOI: 10.1371/journal.pone.0141040] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Accepted: 10/02/2015] [Indexed: 11/18/2022] Open
Abstract
In Bacillus subtilis the protective layers that surround the mature spore are formed by over seventy different proteins. Some of those proteins have a regulatory role on the assembly of other coat proteins and are referred to as morphogenetic factors. CotE is a major morphogenetic factor, known to form a ring around the forming spore and organize the deposition of the outer surface layers. CotH is a CotE-dependent protein known to control the assembly of at least nine other coat proteins. We report that CotH also controls the assembly of CotE and that this mutual dependency is due to a direct interaction between the two proteins. The C-terminal end of CotE is essential for this direct interaction and CotH cannot bind to mutant CotE deleted of six or nine C-terminal amino acids. However, addition of a negatively charged amino acid to those deleted versions of CotE rescues the interaction.
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Affiliation(s)
| | - Teja Sirec
- Department of Biology, Federico II University, Naples, Italy
| | | | - Anna Crispino
- Department of Biology, Federico II University, Naples, Italy
| | - Anella Saggese
- Department of Biology, Federico II University, Naples, Italy
| | | | | | - Adam Driks
- Department of Microbiology and Immunology, Infectious Disease and Immunology Research Institute, Loyola University Chicago, Maywood, IL, United States of America
| | - Ezio Ricca
- Department of Biology, Federico II University, Naples, Italy
- * E-mail:
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25
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Li W, Shi H, Ding H, Wang L, Zhang Y, Li X, Wang F. Cell Surface Display and Characterization of Rhizopus oryzae Lipase in Pichia pastoris Using Sed1p as an Anchor Protein. Curr Microbiol 2015; 71:150-5. [DOI: 10.1007/s00284-015-0835-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2015] [Accepted: 04/05/2015] [Indexed: 11/24/2022]
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26
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Bonavita R, Isticato R, Maurano F, Ricca E, Rossi M. Mucosal immunity induced by gliadin-presenting spores of Bacillus subtilis in HLA-DQ8-transgenic mice. Immunol Lett 2015; 165:84-9. [PMID: 25944582 DOI: 10.1016/j.imlet.2015.04.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2015] [Revised: 04/17/2015] [Accepted: 04/22/2015] [Indexed: 11/16/2022]
Abstract
The induction of mucosal immunity requires efficient antigen delivery and adjuvant systems. Probiotic bacterial strains are considered to be very promising tools to address both of these needs. In particular, Bacillus subtilis spores are currently under investigation as a long-lived, protease-resistant adjuvant system for different antigens. Furthermore, a non-recombinant approach has been developed based on the stable adsorption of antigen on the spore surface. In the present study, we explored this strategy as a means of modulating the immune response to wheat gliadin, the triggering agent of celiac disease (CD), an enteropathy driven by inflammatory CD4(+) T cells. Gliadin adsorption was tested on untreated or autoclaved wild-type (wt) and mutant (cotH or cotE) spores. We found that gliadin was stably and maximally adsorbed by autoclaved wt spores. We then tested the immune properties of the spore-adsorbed gliadin in HLA-DQ8-transgenic mice, which express one of the two HLA heterodimers associated with CD. In vitro, spore-adsorbed gliadin was efficiently taken up by mouse dendritic cells (DCs). Interestingly, gliadin-pulsed DCs efficiently stimulated splenic CD4(+) T cells from mice immunised with spore-adsorbed gliadin. Nasal pre-dosing with spore-adsorbed gliadin failed to down-regulate the ongoing cellular response in gliadin-sensitised DQ8 mice. Notably, naïve mice inoculated intranasally with multiple doses of spore-adsorbed gliadin developed an intestinal antigen-specific CD4(+) T cell-mediated response. In conclusion, our data highlight the ability of spore-adsorbed gliadin to elicit a T-cell response in the gut that could be exploitable for developing immune strategies in CD.
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Affiliation(s)
| | | | | | - Ezio Ricca
- Department of Biology, Federico II University, Naples, Italy
| | - Mauro Rossi
- Institute of Food Sciences, CNR, Avellino, Italy.
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27
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Rusciano G, Zito G, Isticato R, Sirec T, Ricca E, Bailo E, Sasso A. Nanoscale chemical imaging of Bacillus subtilis spores by combining tip-enhanced Raman scattering and advanced statistical tools. ACS NANO 2014; 8:12300-12309. [PMID: 25415422 DOI: 10.1021/nn504595k] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Tip-enhanced Raman Scattering (TERS) has recently emerged as a powerful spectroscopic technique capable of providing subdiffraction morphological and chemical information on samples. In this work, we apply TERS spectroscopy for surface analysis of the Bacillus subtilis spore, a very attractive biosystem for a wide range of applications regulated by the spore surface properties. The observed spectra reflect the complex and heterogeneous environment explored by the plasmonic tip, therefore exhibiting significant point-to-point variations at the nanoscale. Herein, we demonstrate that TERS data processing via principal component analysis allows handling such spectral changes, thus enabling an unbiased correlative imaging based on TERS. Our experimental outcomes suggest a denser arrangement of both proteins and carbohydrates on specific spore surface regions simultaneously revealed by AFM phase imaging. Successful TERS analysis of spores' surface is useful for bacterial surface-display systems and drug delivery applications.
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Affiliation(s)
- Giulia Rusciano
- Department of Physics and ‡Department of Biology, University of Naples Federico II , via Cintia, 80126-I Naples, Italy
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28
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The sps Gene Products Affect the Germination, Hydrophobicity, and Protein Adsorption of Bacillus subtilis Spores. Appl Environ Microbiol 2014; 80:7293-302. [PMID: 25239894 DOI: 10.1128/aem.02893-14] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2014] [Accepted: 09/13/2014] [Indexed: 11/20/2022] Open
Abstract
The multilayered surface of the Bacillus subtilis spore is composed of proteins and glycans. While over 70 different proteins have been identified as surface components, carbohydrates associated with the spore surface have not been characterized in detail yet. Bioinformatic data suggest that the 11 products of the sps operon are involved in the synthesis of polysaccharides present on the spore surface, but an experimental validation is available only for the four distal genes of the operon. Here, we report a transcriptional analysis of the sps operon and a functional study performed by constructing and analyzing two null mutants lacking either all or only the promoter-proximal gene of the operon. Our results show that both sps mutant spores apparently have normal coat and crust but have a small germination defect and are more hydrophobic than wild-type spores. We also show that spores lacking all Sps proteins are highly adhesive and form extensive clumps. In addition, sps mutant spores have an increased efficiency in adsorbing a heterologous enzyme, suggesting that hydrophobic force is a major determinant of spore adsorption and indicating that a deep understanding of the surface properties of the spore is essential for its full development as a surface display platform.
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29
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Abstract
ABSTRACT
A variety of bioactive peptides and proteins have been successfully displayed on the surface of recombinant spores of
Bacillus subtilis
and other sporeformers. In most cases, spore display has been achieved by stably anchoring the foreign molecules to endogenous surface proteins or parts of them. Recombinant spores have been proposed for a large number of potential applications ranging from oral vaccine vehicles to bioremediation tools, and including biocatalysts, probiotics for animal or human use, as well as the generation and screening of mutagenesis libraries. In addition, a nonrecombinant approach has been recently developed to adsorb antigens and enzymes on the spore surface. This nonrecombinant approach appears particularly well suited for applications involving the delivery of active molecules to human or animal mucosal surfaces. Both the recombinant and nonrecombinant spore display systems have a number of advantages over cell- or phage-based systems. The stability, safety of spores of several bacterial species, and amenability to laboratory manipulations, together with the lack of some constraints limiting the use of other systems, make the spore a highly efficient platform to display heterologous proteins.
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30
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Pan JG, Choi SK, Jung HC, Kim EJ. Display of native proteins on Bacillus subtilis spores. FEMS Microbiol Lett 2014; 358:209-17. [PMID: 25168353 DOI: 10.1111/1574-6968.12558] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2014] [Revised: 07/29/2014] [Accepted: 07/30/2014] [Indexed: 01/07/2023] Open
Abstract
In principle, protein display is enabled by fusing target proteins to naturally secreted, surface-anchored protein motifs. In this work, we developed a method of native protein display on the Bacillus spore surface that obviates the need to construct fusion proteins to display a motif. Spore coat proteins are expressed in the mother cell compartment and are subsequently assembled and deposited on the surface of spores. Therefore, target proteins overexpressed in the mother cell compartment during the late sporulation phase were expected to be targeted and displayed on the spore surface. As a proof of principle, we demonstrated the display of carboxymethylcellulase (CMCase) in its native form on the spore surface. The target protein, CMCase, was expressed under the control of the cry1Aa promoter, which is controlled by σ(E) and σ(K) and is expressed in the mother cell compartment. The correct display was confirmed using enzyme activity assays, flow cytometry, and immunogold electron microscopy. In addition, we demonstrated the display of a β-galactosidase tetramer and confirmed its correct display using enzyme activity assays and protein characterization. This native protein display system, combined with the robust nature of Bacillus spores, will broaden the range of displayable target proteins. Consequently, the applications of display technology will be expanded, including high-throughput screening, vaccines, biosensors, biocatalysis, bioremediation, and other innovative bioprocesses.
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Affiliation(s)
- Jae-Gu Pan
- Superbacteria Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, Korea
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31
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Ricca E, Baccigalupi L, Cangiano G, De Felice M, Isticato R. Mucosal vaccine delivery by non-recombinant spores of Bacillus subtilis. Microb Cell Fact 2014; 13:115. [PMID: 25112405 PMCID: PMC4249717 DOI: 10.1186/s12934-014-0115-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Accepted: 07/31/2014] [Indexed: 01/23/2023] Open
Abstract
Development of mucosal vaccines strongly relies on an efficient delivery system and, over the years, a variety of approaches based on phages, bacteria or synthetic nanoparticles have been proposed to display and deliver antigens. The spore of Bacillus subtilis displaying heterologous antigens has also been considered as a mucosal vaccine vehicle, and shown able to conjugate some advantages of live microrganisms with some of synthetic nanoparticles. Here we review the use of non-recombinant spores of B. subtilis as a delivery system for mucosal immunizations. The non-recombinant display is based on the adsorption of heterologous molecules on the spore surface without the need of genetic manipulations, thus avoiding all concerns about the use and environmental release of genetically modified microorganisms. In addition, adsorbed molecules are stabilized and protected by the interaction with the spore, suggesting that this system could reduce the rapid degradation of the antigen, often observed with other delivery systems and identified as a major drawback of mucosal vaccines.
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Sirec T, Cangiano G, Baccigalupi L, Ricca E, Isticato R. The spore surface of intestinal isolates ofBacillus subtilis. FEMS Microbiol Lett 2014; 358:194-201. [DOI: 10.1111/1574-6968.12538] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2014] [Revised: 07/14/2014] [Accepted: 07/14/2014] [Indexed: 11/30/2022] Open
Affiliation(s)
- Teja Sirec
- Department of Biology; University of Naples Federico II; Naples Italy
| | | | | | - Ezio Ricca
- Department of Biology; University of Naples Federico II; Naples Italy
| | - Rachele Isticato
- Department of Biology; University of Naples Federico II; Naples Italy
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Pesce G, Rusciano G, Sasso A, Isticato R, Sirec T, Ricca E. Surface charge and hydrodynamic coefficient measurements of Bacillus subtilis spore by optical tweezers. Colloids Surf B Biointerfaces 2014; 116:568-75. [PMID: 24583259 DOI: 10.1016/j.colsurfb.2014.01.039] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Revised: 01/21/2014] [Accepted: 01/26/2014] [Indexed: 10/25/2022]
Abstract
In this work we report on the simultaneous measurement of the hydrodynamic coefficient and the electric charge of single Bacillus subtilis spores. The latter has great importance in protein binding to spores and in the adhesion of spores onto surfaces. The charge and the hydrodynamic coefficient were measured by an accurate procedure based on the analysis of the motion of single spores confined by an optical trap. The technique has been validated using charged spherical polystyrene beads. The excellent agreement of our results with the expected values demonstrates the quality of our procedure. We measured the charge of spores of B. subtilis purified from a wild type strain and from two isogenic mutants characterized by an altered spore surface. Our technique is able to discriminate the three spore types used, by their charge and by their hydrodynamic coefficient which is related to the hydrophobic properties of the spore surface.
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Affiliation(s)
- Giuseppe Pesce
- Dipartimento di Fisica Università degli studi di Napoli, Complesso Universitario Monte S. Angelo, Via Cintia 80126, Napoli, Italy.
| | - Giulia Rusciano
- Dipartimento di Fisica Università degli studi di Napoli, Complesso Universitario Monte S. Angelo, Via Cintia 80126, Napoli, Italy
| | - Antonio Sasso
- Dipartimento di Fisica Università degli studi di Napoli, Complesso Universitario Monte S. Angelo, Via Cintia 80126, Napoli, Italy; CNR Istituto Nazionale di Ottica - Sezione di Napoli, Via Campi Flegrei, 34 80078 Pozzuoli, Napoli, Italy
| | - Rachele Isticato
- Dipartimento di Biologia Università degli studi di Napoli, Complesso Universitario Monte S. Angelo, Via Cintia 80126, Napoli, Italy
| | - Teja Sirec
- Dipartimento di Biologia Università degli studi di Napoli, Complesso Universitario Monte S. Angelo, Via Cintia 80126, Napoli, Italy
| | - Ezio Ricca
- Dipartimento di Biologia Università degli studi di Napoli, Complesso Universitario Monte S. Angelo, Via Cintia 80126, Napoli, Italy
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