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Cianciotto NP. The type II secretion system as an underappreciated and understudied mediator of interbacterial antagonism. Infect Immun 2024; 92:e0020724. [PMID: 38980047 PMCID: PMC11320942 DOI: 10.1128/iai.00207-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/10/2024] Open
Abstract
Interbacterial antagonism involves all major phyla, occurs across the full range of ecological niches, and has great significance for the environment, clinical arena, and agricultural and industrial sectors. Though the earliest insight into interbacterial antagonism traces back to the discovery of antibiotics, a paradigm shift happened when it was learned that protein secretion systems (e.g., types VI and IV secretion systems) deliver toxic "effectors" against competitors. However, a link between interbacterial antagonism and the Gram-negative type II secretion system (T2SS), which exists in many pathogens and environmental species, is not evident in prior reviews on bacterial competition or T2SS function. A current examination of the literature revealed four examples of a T2SS or one of its known substrates having a bactericidal activity against a Gram-positive target or another Gram-negative. When further studied, the T2SS effectors proved to be peptidases that target the peptidoglycan of the competitor. There are also reports of various bacteriolytic enzymes occurring in the culture supernatants of some other Gram-negative species, and a link between these bactericidal activities and T2SS is suggested. Thus, a T2SS can be a mediator of interbacterial antagonism, and it is possible that many T2SSs have antibacterial outputs. Yet, at present, the T2SS remains relatively understudied for its role in interbacterial competition. Arguably, there is a need to analyze the T2SSs of a broader range of species for their role in interbacterial antagonism. Such investigation offers, among other things, a possible pathway toward developing new antimicrobials for treating disease.
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Affiliation(s)
- Nicholas P. Cianciotto
- Department of Microbiology-Immunology, Northwestern University School of Medicine, Chicago, Illinois, USA
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2
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Ouyang P, Wang Y, Peng X, Shi X, Chen X, Li Z, Ma Y. Harnessing plant-beneficial bacterial encapsulation: A sustainable strategy for facilitating cadmium bioaccumulation in Medicago sativa. JOURNAL OF HAZARDOUS MATERIALS 2024; 476:135232. [PMID: 39024768 DOI: 10.1016/j.jhazmat.2024.135232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2024] [Revised: 06/25/2024] [Accepted: 07/15/2024] [Indexed: 07/20/2024]
Abstract
Plant-beneficial bacteria (PBB) have emerged as a promising approach for assisting phytoremediation of heavy metal (HM)-contaminated soils. However, their colonization efficiency is often challenged by complex soil environments. In this study, we screened one rhizobacterium (Klebsiella variicola Y38) and one endophytic bacterium (Serratia surfactantfaciens Y15) isolated from HM-contaminated soils and plants for their high resistance to Cd and strong growth-promoting abilities. These strains were encapsulated individually or in combination with alginate and applied with Medicago sativa in Cd-contaminated soil pot experiments. The effectiveness of different bacterial formulations in promoting plant growth and enhancing Cd bioconcentration in M. sativa was evaluated. Results showed that PBB application enhanced plant growth and antioxidant capacity while reducing oxidative damage. Encapsulated formulations outperformed unencapsulated ones, with combined formulations yielding superior results to individual applications. Quantitative PCR indicated enhanced PBB colonization in Cd-contaminated soils with alginate encapsulation, potentially explaining the higher efficacy of alginate-encapsulated PBB. Additionally, the bacterial agents modified Cd speciation in soils, resulting in increased Cd bioaccumulation in M. sativa by 217-337 %. The alginate-encapsulated mixed bacterial agent demonstrated optimal effectiveness, increasing the Cd transfer coefficient by 3.2-fold. Structural equation modeling and correlation analysis elucidated that K. variicola Y38 promoted Cd bioaccumulation in M. sativa roots by reducing oxidative damage and enhancing root growth, while S. surfactantfaciens Y15 facilitated Cd translocation to shoots, promoting shoot growth. The combined application of these bacteria leveraged the benefits of both strains. These findings contribute to diversifying strategies for effectively and sustainably remediating Cd-contaminated soils, while laying a foundation for future investigations into bacteria-assisted phytoremediation.
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Affiliation(s)
- Peng Ouyang
- Chongqing Key Laboratory of Interface Process and Soil Health, College of Resources and Environment, Southwest University, Chongqing 400716, China
| | - Yue Wang
- Chongqing Key Laboratory of Interface Process and Soil Health, College of Resources and Environment, Southwest University, Chongqing 400716, China
| | - Xinyue Peng
- Hanhong College, Southwest University, Chongqing 400716, China
| | - Xiaojun Shi
- College of Resources and Environment, Southwest University, Chongqing 400716, China
| | - Xinping Chen
- College of Resources and Environment, Southwest University, Chongqing 400716, China
| | - Zhenlun Li
- Chongqing Key Laboratory of Interface Process and Soil Health, College of Resources and Environment, Southwest University, Chongqing 400716, China
| | - Ying Ma
- Chongqing Key Laboratory of Interface Process and Soil Health, College of Resources and Environment, Southwest University, Chongqing 400716, China.
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Otto SB, Servajean R, Lemopoulos A, Bitbol AF, Blokesch M. Interactions between pili affect the outcome of bacterial competition driven by the type VI secretion system. Curr Biol 2024; 34:2403-2417.e9. [PMID: 38749426 DOI: 10.1016/j.cub.2024.04.041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Revised: 04/09/2024] [Accepted: 04/22/2024] [Indexed: 06/06/2024]
Abstract
The bacterial type VI secretion system (T6SS) is a widespread, kin-discriminatory weapon capable of shaping microbial communities. Due to the system's dependency on contact, cellular interactions can lead to either competition or kin protection. Cell-to-cell contact is often accomplished via surface-exposed type IV pili (T4Ps). In Vibrio cholerae, these T4Ps facilitate specific interactions when the bacteria colonize natural chitinous surfaces. However, it has remained unclear whether and, if so, how these interactions affect the bacterium's T6SS-mediated killing. In this study, we demonstrate that pilus-mediated interactions can be harnessed by T6SS-equipped V. cholerae to kill non-kin cells under liquid growth conditions. We also show that the naturally occurring diversity of pili determines the likelihood of cell-to-cell contact and, consequently, the extent of T6SS-mediated competition. To determine the factors that enable or hinder the T6SS's targeted reduction of competitors carrying pili, we developed a physics-grounded computational model for autoaggregation. Collectively, our research demonstrates that T4Ps involved in cell-to-cell contact can impose a selective burden when V. cholerae encounters non-kin cells that possess an active T6SS. Additionally, our study underscores the significance of T4P diversity in protecting closely related individuals from T6SS attacks through autoaggregation and spatial segregation.
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Affiliation(s)
- Simon B Otto
- Laboratory of Molecular Microbiology, Global Health Institute, School of Life Sciences, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Richard Servajean
- Laboratory of Computational Biology and Theoretical Biophysics, Institute of Bioengineering, School of Life Sciences, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland; SIB Swiss Institute of Bioinformatics, 1015 Lausanne, Switzerland
| | - Alexandre Lemopoulos
- Laboratory of Molecular Microbiology, Global Health Institute, School of Life Sciences, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Anne-Florence Bitbol
- Laboratory of Computational Biology and Theoretical Biophysics, Institute of Bioengineering, School of Life Sciences, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland; SIB Swiss Institute of Bioinformatics, 1015 Lausanne, Switzerland
| | - Melanie Blokesch
- Laboratory of Molecular Microbiology, Global Health Institute, School of Life Sciences, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland.
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Arbulu S, Kjos M. Revisiting the Multifaceted Roles of Bacteriocins : The Multifaceted Roles of Bacteriocins. MICROBIAL ECOLOGY 2024; 87:41. [PMID: 38351266 PMCID: PMC10864542 DOI: 10.1007/s00248-024-02357-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Accepted: 02/01/2024] [Indexed: 02/16/2024]
Abstract
Bacteriocins are gene-encoded antimicrobial peptides produced by bacteria. These peptides are heterogeneous in terms of structure, antimicrobial activities, biosynthetic clusters, and regulatory mechanisms. Bacteriocins are widespread in nature and may contribute to microbial diversity due to their capacity to target specific bacteria. Primarily studied as food preservatives and therapeutic agents, their function in natural settings is however less known. This review emphasizes the ecological significance of bacteriocins as multifunctional peptides by exploring bacteriocin distribution, mobility, and their impact on bacterial population dynamics and biofilms.
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Affiliation(s)
- Sara Arbulu
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, Ås, Norway.
| | - Morten Kjos
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, Ås, Norway.
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Stulanovic N, Kerdel Y, Rezende L, Deflandre B, Burguet P, Belde L, Denoel R, Tellatin D, Rigolet A, Hanikenne M, Quinton L, Ongena M, Rigali S. Nitrogen sources enhance siderophore-mediated competition for iron between potato common scab and late blight causative agents. Metallomics 2024; 16:mfae004. [PMID: 38244228 DOI: 10.1093/mtomcs/mfae004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2023] [Accepted: 01/18/2024] [Indexed: 01/22/2024]
Abstract
How do pathogens affecting the same host interact with each other? We evaluated here the types of microbe-microbe interactions taking place between Streptomyces scabiei and Phytophthora infestans, the causative agents of common scab and late blight diseases in potato crops, respectively. Under most laboratory culture conditions tested, S. scabiei impaired or completely inhibited the growth of P. infestans by producing either soluble and/or volatile compounds. Increasing peptone levels correlated with increased inhibition of P. infestans. Comparative metabolomics showed that production of S. scabiei siderophores (desferrioxamines, pyochelin, scabichelin, and turgichelin) increased with the quantity of peptone, thereby suggesting that they participate in the inhibition of the oomycete growth. Mass spectrometry imaging further uncovered that the zones of secreted siderophores and of P. infestans growth inhibition coincided. Moreover, either the repression of siderophore production or the neutralization of their iron-chelating activity led to a resumption of P. infestans growth. Replacement of peptone by natural nitrogen sources such as ammonium nitrate, sodium nitrate, ammonium sulfate, and urea also triggered siderophore production in S. scabiei. Interestingly, nitrogen source-induced siderophore production also inhibited the growth of Alternaria solani, the causative agent of the potato early blight. Overall, our work further emphasizes the importance of competition for iron between microorganisms that colonize the same niche. As common scab never alters the vegetative propagation of tubers, we propose that S. scabiei, under certain conditions, could play a protective role for its hosts against much more destructive pathogens through exploitative iron competition and volatile compound production.
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Affiliation(s)
- Nudzejma Stulanovic
- InBioS-Center for Protein Engineering, Institut de Chimie, University of Liège, B-4000 Liège, Belgium
| | - Yasmine Kerdel
- InBioS-Center for Protein Engineering, Institut de Chimie, University of Liège, B-4000 Liège, Belgium
| | - Lucas Rezende
- Hedera-22, Boulevard du Rectorat 27b, B-4000 Liège, Belgium
| | - Benoit Deflandre
- InBioS-Center for Protein Engineering, Institut de Chimie, University of Liège, B-4000 Liège, Belgium
| | - Pierre Burguet
- Molecular Systems (MolSys), Department of Chemistry, University of Liège, B-4000 Liège, Belgium
| | - Loïc Belde
- InBioS-Center for Protein Engineering, Institut de Chimie, University of Liège, B-4000 Liège, Belgium
| | - Romane Denoel
- InBioS-Center for Protein Engineering, Institut de Chimie, University of Liège, B-4000 Liège, Belgium
| | - Déborah Tellatin
- InBioS-Center for Protein Engineering, Institut de Chimie, University of Liège, B-4000 Liège, Belgium
| | - Augustin Rigolet
- Microbial Processes and Interactions, TERRA Teaching and Research Center, BioEcoAgro, Joint Research Unit/UMR transfrontalière 1158, University of Liège-Gembloux Agro-Bio Tech, Gembloux, Belgium
| | - Marc Hanikenne
- InBioS-PhytoSystems, Translational Plant Biology, University of Liège, B-4000 Liège, Belgium
| | - Loïc Quinton
- Molecular Systems (MolSys), Department of Chemistry, University of Liège, B-4000 Liège, Belgium
| | - Marc Ongena
- Microbial Processes and Interactions, TERRA Teaching and Research Center, BioEcoAgro, Joint Research Unit/UMR transfrontalière 1158, University of Liège-Gembloux Agro-Bio Tech, Gembloux, Belgium
| | - Sébastien Rigali
- InBioS-Center for Protein Engineering, Institut de Chimie, University of Liège, B-4000 Liège, Belgium
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Timme S, Wendler S, Klassert TE, Saraiva JP, da Rocha UN, Wittchen M, Schramm S, Ehricht R, Monecke S, Edel B, Rödel J, Löffler B, Ramirez MS, Slevogt H, Figge MT, Tuchscherr L. Competitive inhibition and mutualistic growth in co-infections: deciphering Staphylococcus aureus-Acinetobacter baumannii interaction dynamics. ISME COMMUNICATIONS 2024; 4:ycae077. [PMID: 38962494 PMCID: PMC11221087 DOI: 10.1093/ismeco/ycae077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/29/2024] [Revised: 06/05/2024] [Accepted: 06/06/2024] [Indexed: 07/05/2024]
Abstract
Staphylococcus aureus (Sa) and Acinetobacter baumannii (Ab) are frequently co-isolated from polymicrobial infections that are severe and refractory to therapy. Here, we apply a combination of wet-lab experiments and in silico modeling to unveil the intricate nature of the Ab/Sa interaction using both, representative laboratory strains and strains co-isolated from clinical samples. This comprehensive methodology allowed uncovering Sa's capability to exert a partial interference on Ab by the expression of phenol-soluble modulins. In addition, we observed a cross-feeding mechanism by which Sa supports the growth of Ab by providing acetoin as an alternative carbon source. This study is the first to dissect the Ab/Sa interaction dynamics wherein competitive and cooperative strategies can intertwine. Through our findings, we illuminate the ecological mechanisms supporting their coexistence in the context of polymicrobial infections. Our research not only enriches our understanding but also opens doors to potential therapeutic avenues in managing these challenging infections.
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Affiliation(s)
- Sandra Timme
- Applied Systems Biology, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knöll Institute, Friedrich Schiller University Jena, Leibniz Centre for Photonics in Infection Research (LPI), D-07743 Jena, Germany
| | - Sindy Wendler
- Institute of Medical Microbiology, Jena University Hospital, D-07740 Jena, Germany
| | - Tilman E Klassert
- Respiratory Infection Dynamics, Helmholtz Centre for Infection Research – HZI, D-38124 Braunschweig, Germany
- Department of Respiratory Medicine and Infectious Diseases, Hannover Medical School, German Center for Lung Research (DZL), BREATH, D-30625 Hannover, Germany
| | - Joao Pedro Saraiva
- Department of Environmental Microbiology, Helmholtz Centre for Environmental Research-UFZ, D-04318 Leipzig, Germany
| | - Ulisses Nunes da Rocha
- Department of Environmental Microbiology, Helmholtz Centre for Environmental Research-UFZ, D-04318 Leipzig, Germany
| | - Manuel Wittchen
- Center for Biotechnology, Bielefeld University, D-33501 Bielefeld, Germany
| | - Sareda Schramm
- Department of Biological Science, Center for Applied Biotechnology Studies, California State University, 800 N State College Blvd, Fullerton, CA 92831, United States
| | - Ralf Ehricht
- Leibniz Institute of Photonic Technology, Leibniz Centre for Photonics in Infection Research (LPI), D-07745 Jena, Germany
- Institute of Physical Chemistry, Friedrich Schiller University Jena, Leibniz Centre for Photonics in Infection Research (LPI) , D-07743 Jena, Germany
| | - Stefan Monecke
- Leibniz Institute of Photonic Technology, Leibniz Centre for Photonics in Infection Research (LPI), D-07745 Jena, Germany
- Institute for Medical Microbiology and Virology, Dresden University Hospital, Dresden, Germany
| | - Birgit Edel
- Institute of Medical Microbiology, Jena University Hospital, D-07740 Jena, Germany
| | - Jürgen Rödel
- Institute of Medical Microbiology, Jena University Hospital, D-07740 Jena, Germany
| | - Bettina Löffler
- Institute of Medical Microbiology, Jena University Hospital, D-07740 Jena, Germany
- Cluster of Excellence Balance of the Microverse, Friedrich Schiller University Jena, D-07743 Jena, Germany
| | - Maria Soledad Ramirez
- Department of Biological Science, Center for Applied Biotechnology Studies, California State University, 800 N State College Blvd, Fullerton, CA 92831, United States
| | - Hortense Slevogt
- Respiratory Infection Dynamics, Helmholtz Centre for Infection Research – HZI, D-38124 Braunschweig, Germany
- Department of Respiratory Medicine and Infectious Diseases, Hannover Medical School, German Center for Lung Research (DZL), BREATH, D-30625 Hannover, Germany
| | - Marc Thilo Figge
- Applied Systems Biology, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knöll Institute, Friedrich Schiller University Jena, Leibniz Centre for Photonics in Infection Research (LPI), D-07743 Jena, Germany
- Cluster of Excellence Balance of the Microverse, Friedrich Schiller University Jena, D-07743 Jena, Germany
- Institute of Microbiology, Faculty of Biological Sciences, Friedrich Schiller University, D-07743 Jena, Germany
| | - Lorena Tuchscherr
- Institute of Medical Microbiology, Jena University Hospital, D-07740 Jena, Germany
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Cantillo Villa Y, Triga A, Katharios P. Polyinfection in Fish Aeromoniasis: A Study of Co-Isolated Aeromonas Species in Aeromonas veronii Outbreaks. Pathogens 2023; 12:1337. [PMID: 38003801 PMCID: PMC10674900 DOI: 10.3390/pathogens12111337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Revised: 11/08/2023] [Accepted: 11/08/2023] [Indexed: 11/26/2023] Open
Abstract
We studied the phenotypic and genomic characteristics related to the virulence and antibiotic resistance of two Aeromonas strains, which were co-isolated before an outbreak of Aeromonas veronii among diseased seabass on Agathonisi Island, Greece, in April 2015. The first strain, AG2.13.2, is a potentially pathogenic mesophilic variant of Aeromonas salmonicida, and the second, AG2.13.5, corresponds to an Aeromonas rivipollensis related to A. rivipollensis KN-Mc-11N1 with an ANI value of 97.32%. AG2.13.2 lacks the type III secretion system just like other mesophilic strains of A. salmonicida. This characteristic has been associated with lower virulence. However, the genome of AG2.13.2 contains other important virulence factors such as type II and type VI secretion systems, and toxins such as rtxA, aerolysin aer/act, and different types of hemolysins. The strain also carries several genes associated with antibiotic resistance such as the tetE efflux pump, and exhibits resistance to tetracycline, ampicillin, and oxolinic acid. In an in vivo challenge test with gilthead seabream larvae, the A. veronii bv sobria strain AG5.28.6 exhibited the highest virulence among all tested strains. Conversely, both A. salmonicida and A. rivipollensis showed minimal virulence when administered alone. Interestingly, when A. veronii bv sobria AG5.28.6 was co-administered with A. rivipollensis, the larvae survival probability increased compared to those exposed to A. veronii bv sobria AG5.28.6 alone. This finding indicates an antagonistic interaction between A. veronii bv sobria AG5.28.6 and A. rivipollensis AG2.13.5. The co-administration of A. veronii bv sobria AG5.28.6 with Aeromonas salmonicida did not yield distinct survival probabilities. Our results validate that the primary pathogen responsible for European seabass aeromoniasis is Aeromonas veronii bv sobria.
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Affiliation(s)
- Yanelys Cantillo Villa
- Institute of Marine Biology, Biotechnology and Aquaculture (IMBBC), Hellenic Centre for Marine Research (HCMR), 71500 Gournes, Greece; (Y.C.V.); (A.T.)
- Department of Biology, University of Crete, 71110 Heraklion, Greece
| | - Adriana Triga
- Institute of Marine Biology, Biotechnology and Aquaculture (IMBBC), Hellenic Centre for Marine Research (HCMR), 71500 Gournes, Greece; (Y.C.V.); (A.T.)
- Department of Biology, University of Crete, 71110 Heraklion, Greece
| | - Pantelis Katharios
- Institute of Marine Biology, Biotechnology and Aquaculture (IMBBC), Hellenic Centre for Marine Research (HCMR), 71500 Gournes, Greece; (Y.C.V.); (A.T.)
- Aquatic Biologicals, Thalassocosmos, 71500 Gournes, Greece
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Carter MQ, Quiñones B, Laniohan N, Carychao D, Pham A, He X, Cooley M. Pathogenicity assessment of Shiga toxin-producing Escherichia coli strains isolated from wild birds in a major agricultural region in California. Front Microbiol 2023; 14:1214081. [PMID: 37822735 PMCID: PMC10562709 DOI: 10.3389/fmicb.2023.1214081] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Accepted: 09/11/2023] [Indexed: 10/13/2023] Open
Abstract
Shiga toxin-producing Escherichia coli (STEC) consists of diverse strains differing in genetic make-up and virulence potential. To better understand the pathogenicity potential of STEC carried by the wildlife, three STEC and one E. coli strains isolated from wild birds near a major agricultural region in California were selected for comparative pathogenomic analyses. Three American crow (Corvus brachyrhynchos) strains, RM9088, RM9513, and RM10410, belonging to phylogroup A with serotypes O109:H48, O9:H30, and O113:H4, respectively, and a red-winged blackbird (Agelaius phoeniceus) strain RM14516 in phylogroup D with serotype O17:H18, were examined. Shiga toxin genes were identified in RM9088 (stx1a), RM10410 (stx1a + stx2d), and RM14516 (stx2a). Unlike STEC O157:H7 strain EDL933, none of the avian STEC strains harbored the pathogenicity islands OI-122, OI-57, and the locus of enterocyte effacement, therefore the type III secretion system biogenesis genes and related effector genes were absent in the three avian STEC genomes. Interestingly, all avian STEC strains exhibited greater (RM9088 and RM14516) or comparable (RM10410) cytotoxicity levels compared with EDL933. Comparative pathogenomic analyses revealed that RM9088 harbored numerous genes encoding toxins, toxins delivery systems, and adherence factors, including heat-labile enterotoxin, serine protease autotransporter toxin Pic, type VI secretion systems, protein adhesin Paa, fimbrial adhesin K88, and colonization factor antigen I. RM9088 also harbored a 36-Kb high pathogenicity island, which is related to iron acquisition and pathogenicity in Yersinia spp. Strain RM14516 carried an acid fitness island like the one in EDL933, containing a nine gene cluster involved in iron acquisition. Genes encoding extracellular serine protease EspP, subtilase cytotoxin, F1C fimbriae, and inverse autotransporter adhesin IatC were only detected in RM14516, and genes encoding serine protease autotransporter EspI and P fimbriae were only identified in RM10410. Although all curli genes were present in avian STEC strains, production of curli fimbriae was only detected for RM9088 and RM14516. Consistently, strong, moderate, and little biofilms were observed for RM9088, RM14516, and RM10410, respectively. Our study revealed novel combinations of virulence factors in two avian strains, which exhibited high level of cytotoxicity and strong biofilm formation. Comparative pathogenomics is powerful in assessing pathogenicity and health risk of STEC strains.
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Affiliation(s)
- Michelle Qiu Carter
- Produce Safety and Microbiology Research Unit, U.S. Department of Agriculture, Agricultural Research Service, Western Regional Research Center, Albany, CA, United States
| | - Beatriz Quiñones
- Produce Safety and Microbiology Research Unit, U.S. Department of Agriculture, Agricultural Research Service, Western Regional Research Center, Albany, CA, United States
| | - Nicole Laniohan
- Produce Safety and Microbiology Research Unit, U.S. Department of Agriculture, Agricultural Research Service, Western Regional Research Center, Albany, CA, United States
| | - Diana Carychao
- Produce Safety and Microbiology Research Unit, U.S. Department of Agriculture, Agricultural Research Service, Western Regional Research Center, Albany, CA, United States
| | - Antares Pham
- Produce Safety and Microbiology Research Unit, U.S. Department of Agriculture, Agricultural Research Service, Western Regional Research Center, Albany, CA, United States
| | - Xiaohua He
- Foodborne Toxin Detection and Prevention Research Unit, U.S. Department of Agriculture, Agricultural Research Service, Western Regional Research Center, Albany, CA, United States
| | - Michael Cooley
- Produce Safety and Microbiology Research Unit, U.S. Department of Agriculture, Agricultural Research Service, Western Regional Research Center, Albany, CA, United States
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Gasparek M, Steel H, Papachristodoulou A. Deciphering mechanisms of production of natural compounds using inducer-producer microbial consortia. Biotechnol Adv 2023; 64:108117. [PMID: 36813010 DOI: 10.1016/j.biotechadv.2023.108117] [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: 07/21/2022] [Revised: 02/03/2023] [Accepted: 02/06/2023] [Indexed: 02/22/2023]
Abstract
Living organisms produce a wide range of metabolites. Because of their potential antibacterial, antifungal, antiviral, or cytostatic properties, such natural molecules are of high interest to the pharmaceutical industry. In nature, these metabolites are often synthesized via secondary metabolic biosynthetic gene clusters that are silent under the typical culturing conditions. Among different techniques used to activate these silent gene clusters, co-culturing of "producer" species with specific "inducer" microbes is a particularly appealing approach due to its simplicity. Although several "inducer-producer" microbial consortia have been reported in the literature and hundreds of different secondary metabolites with attractive biopharmaceutical properties have been described as a result of co-cultivating inducer-producer consortia, less attention has been devoted to the understanding of the mechanisms and possible means of induction for production of secondary metabolites in co-cultures. This lack of understanding of fundamental biological functions and inter-species interactions significantly limits the diversity and yield of valuable compounds using biological engineering tools. In this review, we summarize and categorize the known physiological mechanisms of production of secondary metabolites in inducer-producer consortia, and then discuss approaches that could be exploited to optimize the discovery and production of secondary metabolites.
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Affiliation(s)
- Miroslav Gasparek
- Department of Engineering Science, University of Oxford, Parks Road, Oxford OX1 3PJ, United Kingdom.
| | - Harrison Steel
- Department of Engineering Science, University of Oxford, Parks Road, Oxford OX1 3PJ, United Kingdom
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Nitrogen-Fixing Symbiotic Paraburkholderia Species: Current Knowledge and Future Perspectives. NITROGEN 2023. [DOI: 10.3390/nitrogen4010010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/11/2023] Open
Abstract
A century after the discovery of rhizobia, the first Beta-proteobacteria species (beta-rhizobia) were isolated from legume nodules in South Africa and South America. Since then, numerous species belonging to the Burkholderiaceae family have been isolated. The presence of a highly branching lineage of nodulation genes in beta-rhizobia suggests a long symbiotic history. In this review, we focus on the beta-rhizobial genus Paraburkholderia, which includes two main groups: the South American mimosoid-nodulating Paraburkholderia and the South African predominantly papilionoid-nodulating Paraburkholderia. Here, we discuss the latest knowledge on Paraburkholderia nitrogen-fixing symbionts in each step of the symbiosis, from their survival in the soil, through the first contact with the legumes until the formation of an efficient nitrogen-fixing symbiosis in root nodules. Special attention is given to the strain P. phymatum STM815T that exhibits extraordinary features, such as the ability to: (i) enter into symbiosis with more than 50 legume species, including the agriculturally important common bean, (ii) outcompete other rhizobial species for nodulation of several legumes, and (iii) endure stressful soil conditions (e.g., high salt concentration and low pH) and high temperatures.
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11
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Dijamentiuk A, Mangavel C, Elfassy A, Michaux F, Burgain J, Rondags E, Delaunay S, Ferrigno S, Revol-Junelles AM, Borges F. Invert emulsions alleviate biotic interactions in bacterial mixed culture. Microb Cell Fact 2023; 22:16. [PMID: 36670385 PMCID: PMC9854087 DOI: 10.1186/s12934-022-02014-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Accepted: 12/31/2022] [Indexed: 01/21/2023] Open
Abstract
The large application potential of microbiomes has led to a great need for mixed culture methods. However, microbial interactions can compromise the maintenance of biodiversity during cultivation in a reactor. In particular, competition among species can lead to a strong disequilibrium in favor of the fittest microorganism. In this study, an invert emulsion system was designed by dispersing culture medium in a mixture of sunflower oil and the surfactant PGPR. Confocal laser scanning microscopy revealed that this system allowed to segregate microorganisms in independent droplets. Granulomorphometric analysis showed that the invert emulsion remains stable during at least 24 h, and that the introduction of bacteria did not have a significant impact on the structure of the invert emulsion. A two-strain antagonistic model demonstrated that this invert emulsion system allows the propagation of two strains without the exclusion of the less-fit bacterium. The monitoring of single-strain cultures of bacteria representative of a cheese microbiota revealed that all but Brevibacterium linens were able to grow. A consortium consisting of Lactococcus lactis subsp. lactis biovar diacetylactis, Streptococcus thermophilus, Leuconostoc mesenteroides, Staphylococcus xylosus, Lactiplantibacillus plantarum and Carnobacterium maltaromaticum was successfully cultivated without detectable biotic interactions. Metabarcoding analysis revealed that the system allowed a better maintenance of alpha diversity and produced a propagated bacterial consortium characterized by a structure closer to the initial state compared to non-emulsified medium. This culture system could be an important tool in the field of microbial community engineering.
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Affiliation(s)
- Alexis Dijamentiuk
- grid.29172.3f0000 0001 2194 6418LIBio, Université de Lorraine, Nancy, France
| | - Cécile Mangavel
- grid.29172.3f0000 0001 2194 6418LIBio, Université de Lorraine, Nancy, France
| | - Annelore Elfassy
- grid.29172.3f0000 0001 2194 6418LIBio, Université de Lorraine, Nancy, France
| | - Florentin Michaux
- grid.29172.3f0000 0001 2194 6418LIBio, Université de Lorraine, Nancy, France
| | - Jennifer Burgain
- grid.29172.3f0000 0001 2194 6418LIBio, Université de Lorraine, Nancy, France
| | - Emmanuel Rondags
- grid.29172.3f0000 0001 2194 6418LRGP, Université de Lorraine, Nancy, France
| | - Stéphane Delaunay
- grid.29172.3f0000 0001 2194 6418LRGP, Université de Lorraine, Nancy, France
| | - Sandie Ferrigno
- grid.29172.3f0000 0001 2194 6418IECL, Equipe BIGS, INRIA Nancy, Université de Lorraine, Nancy, France
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12
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A Putative Lipoprotein Mediates Cell-Cell Contact for Type VI Secretion System-Dependent Killing of Specific Competitors. mBio 2022; 13:e0308521. [PMID: 35404117 PMCID: PMC9040878 DOI: 10.1128/mbio.03085-21] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Interbacterial competition is prevalent in host-associated microbiota, where it can shape community structure and function, impacting host health in both positive and negative ways. However, the factors that permit bacteria to discriminate among their various neighbors for targeted elimination of competitors remain elusive. We identified a putative lipoprotein (TasL) in Vibrio species that mediates cell-cell attachment with a subset of target strains, allowing inhibitors to target specific competitors for elimination. Here, we describe this putative lipoprotein, which is associated with the broadly distributed type VI secretion system (T6SS), by studying symbiotic Vibrio fischeri, which uses the T6SS to compete for colonization sites in their squid host. We demonstrate that TasL allows V. fischeri cells to restrict T6SS-dependent killing to certain genotypes by selectively integrating competitor cells into aggregates while excluding other cell types. TasL is also required for T6SS-dependent competition within juvenile squid, indicating that the adhesion factor is active in the host. Because TasL homologs are found in other host-associated bacterial species, this newly described cell-cell attachment mechanism has the potential to impact microbiome structure within diverse hosts. IMPORTANCE T6SSs are broadly distributed interbacterial weapons that share an evolutionary history with bacteriophage. Because the T6SS can be used to kill neighboring cells, it can impact the spatial distribution and biological function of both free-living and host-associated microbial communities. Like their phage relatives, T6SS+ cells must sufficiently bind competitor cells to deliver their toxic effector proteins through the syringe-like apparatus. Although phage use receptor-binding proteins (RBPs) and tail fibers to selectively bind prey cells, the biophysical properties that mediate this cell-cell contact for T6SS-mediated killing remain unknown. Here, we identified a large, predicted lipoprotein that is coordinately expressed with T6SS proteins and facilitates the contact that is necessary for the T6SS-dependent elimination of competitors in a natural host. Similar to phage RBPs and tail fibers, this lipoprotein is required for T6SS+ cells to discriminate between prey and nonprey cell types, revealing new insight into prey selection during T6SS-mediated competition.
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13
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Hermansen S, Linke D, Leo JC. Transmembrane β-barrel proteins of bacteria: From structure to function. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2022; 128:113-161. [PMID: 35034717 DOI: 10.1016/bs.apcsb.2021.07.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
The outer membrane of Gram-negative bacteria is a specialized organelle conferring protection to the cell against various environmental stresses and resistance to many harmful compounds. The outer membrane has a number of unique features, including an asymmetric lipid bilayer, the presence of lipopolysaccharides and an individual proteome. The vast majority of the integral transmembrane proteins in the outer membrane belongs to the family of β-barrel proteins. These evolutionarily related proteins share a cylindrical, anti-parallel β-sheet core fold spanning the outer membrane. The loops and accessory domains attached to the β-barrel allow for a remarkable versatility in function for these proteins, ranging from diffusion pores and transporters to enzymes and adhesins. We summarize the current knowledge on β-barrel structure and folding and give an overview of their functions, evolution, and potential as drug targets.
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Affiliation(s)
- Simen Hermansen
- Section for Genetics and Evolutionary Biology, Department of Biosciences, University of Oslo, Oslo, Norway
| | - Dirk Linke
- Section for Genetics and Evolutionary Biology, Department of Biosciences, University of Oslo, Oslo, Norway
| | - Jack C Leo
- Antimicrobial resistance, Omics and Microbiota Group, Department of Biosciences, Nottingham Trent University, Nottingham, United Kingdom.
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14
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Alexander LT, Lepore R, Kryshtafovych A, Adamopoulos A, Alahuhta M, Arvin AM, Bomble YJ, Böttcher B, Breyton C, Chiarini V, Chinnam NB, Chiu W, Fidelis K, Grinter R, Gupta GD, Hartmann MD, Hayes CS, Heidebrecht T, Ilari A, Joachimiak A, Kim Y, Linares R, Lovering AL, Lunin VV, Lupas AN, Makbul C, Michalska K, Moult J, Mukherjee PK, Nutt W(S, Oliver SL, Perrakis A, Stols L, Tainer JA, Topf M, Tsutakawa SE, Valdivia‐Delgado M, Schwede T. Target highlights in CASP14: Analysis of models by structure providers. Proteins 2021; 89:1647-1672. [PMID: 34561912 PMCID: PMC8616854 DOI: 10.1002/prot.26247] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2021] [Revised: 09/13/2021] [Accepted: 09/16/2021] [Indexed: 12/11/2022]
Abstract
The biological and functional significance of selected Critical Assessment of Techniques for Protein Structure Prediction 14 (CASP14) targets are described by the authors of the structures. The authors highlight the most relevant features of the target proteins and discuss how well these features were reproduced in the respective submitted predictions. The overall ability to predict three-dimensional structures of proteins has improved remarkably in CASP14, and many difficult targets were modeled with impressive accuracy. For the first time in the history of CASP, the experimentalists not only highlighted that computational models can accurately reproduce the most critical structural features observed in their targets, but also envisaged that models could serve as a guidance for further studies of biologically-relevant properties of proteins.
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Affiliation(s)
- Leila T. Alexander
- Biozentrum, University of BaselBaselSwitzerland
- Computational Structural BiologySIB Swiss Institute of BioinformaticsBaselSwitzerland
| | | | | | - Athanassios Adamopoulos
- Oncode Institute and Division of BiochemistryNetherlands Cancer InstituteAmsterdamThe Netherlands
| | - Markus Alahuhta
- Bioscience Center, National Renewable Energy LaboratoryGoldenColoradoUSA
| | - Ann M. Arvin
- Department of PediatricsStanford University School of MedicineStanfordCaliforniaUSA
- Microbiology and ImmunologyStanford University School of MedicineStanfordCaliforniaUSA
| | - Yannick J. Bomble
- Bioscience Center, National Renewable Energy LaboratoryGoldenColoradoUSA
| | - Bettina Böttcher
- Biocenter and Rudolf Virchow Center, Julius‐Maximilians Universität WürzburgWürzburgGermany
| | - Cécile Breyton
- Univ. Grenoble Alpes, CNRS, CEA, Institute for Structural BiologyGrenobleFrance
| | - Valerio Chiarini
- Program in Structural Biology and BiophysicsInstitute of Biotechnology, University of HelsinkiHelsinkiFinland
| | - Naga babu Chinnam
- Department of Molecular and Cellular OncologyThe University of Texas M.D. Anderson Cancer CenterHoustonTexasUSA
| | - Wah Chiu
- Microbiology and ImmunologyStanford University School of MedicineStanfordCaliforniaUSA
- BioengineeringStanford University School of MedicineStanfordCaliforniaUSA
- Division of Cryo‐EM and Bioimaging SSRLSLAC National Accelerator LaboratoryMenlo ParkCaliforniaUSA
| | | | - Rhys Grinter
- Infection and Immunity Program, Biomedicine Discovery Institute and Department of MicrobiologyMonash UniversityClaytonAustralia
| | - Gagan D. Gupta
- Radiation Biology & Health Sciences DivisionBhabha Atomic Research CentreMumbaiIndia
| | - Marcus D. Hartmann
- Department of Protein EvolutionMax Planck Institute for Developmental BiologyTübingenGermany
| | - Christopher S. Hayes
- Department of Molecular, Cellular and Developmental BiologyUniversity of California, Santa BarbaraSanta BarbaraCaliforniaUSA
- Biomolecular Science and Engineering ProgramUniversity of California, Santa BarbaraSanta BarbaraCaliforniaUSA
| | - Tatjana Heidebrecht
- Oncode Institute and Division of BiochemistryNetherlands Cancer InstituteAmsterdamThe Netherlands
| | - Andrea Ilari
- Institute of Molecular Biology and Pathology of the National Research Council of Italy (CNR)RomeItaly
| | - Andrzej Joachimiak
- Center for Structural Genomics of Infectious Diseases, Consortium for Advanced Science and Engineering, University of ChicagoChicagoIllinoisUSA
- X‐ray Science DivisionArgonne National Laboratory, Structural Biology CenterArgonneIllinoisUSA
- Department of Biochemistry and Molecular BiologyUniversity of ChicagoChicagoIllinoisUSA
| | - Youngchang Kim
- Center for Structural Genomics of Infectious Diseases, Consortium for Advanced Science and Engineering, University of ChicagoChicagoIllinoisUSA
- X‐ray Science DivisionArgonne National Laboratory, Structural Biology CenterArgonneIllinoisUSA
| | - Romain Linares
- Univ. Grenoble Alpes, CNRS, CEA, Institute for Structural BiologyGrenobleFrance
| | | | - Vladimir V. Lunin
- Bioscience Center, National Renewable Energy LaboratoryGoldenColoradoUSA
| | - Andrei N. Lupas
- Department of Protein EvolutionMax Planck Institute for Developmental BiologyTübingenGermany
| | - Cihan Makbul
- Biocenter and Rudolf Virchow Center, Julius‐Maximilians Universität WürzburgWürzburgGermany
| | - Karolina Michalska
- Center for Structural Genomics of Infectious Diseases, Consortium for Advanced Science and Engineering, University of ChicagoChicagoIllinoisUSA
- X‐ray Science DivisionArgonne National Laboratory, Structural Biology CenterArgonneIllinoisUSA
| | - John Moult
- Department of Cell Biology and Molecular GeneticsInstitute for Bioscience and Biotechnology Research, University of MarylandRockvilleMarylandUSA
| | - Prasun K. Mukherjee
- Nuclear Agriculture & Biotechnology DivisionBhabha Atomic Research CentreMumbaiIndia
| | - William (Sam) Nutt
- Center for Structural Genomics of Infectious Diseases, Consortium for Advanced Science and Engineering, University of ChicagoChicagoIllinoisUSA
- X‐ray Science DivisionArgonne National Laboratory, Structural Biology CenterArgonneIllinoisUSA
| | - Stefan L. Oliver
- Department of PediatricsStanford University School of MedicineStanfordCaliforniaUSA
| | - Anastassis Perrakis
- Oncode Institute and Division of BiochemistryNetherlands Cancer InstituteAmsterdamThe Netherlands
| | - Lucy Stols
- Center for Structural Genomics of Infectious Diseases, Consortium for Advanced Science and Engineering, University of ChicagoChicagoIllinoisUSA
- X‐ray Science DivisionArgonne National Laboratory, Structural Biology CenterArgonneIllinoisUSA
| | - John A. Tainer
- Department of Molecular and Cellular OncologyThe University of Texas M.D. Anderson Cancer CenterHoustonTexasUSA
- Department of Cancer BiologyUniversity of Texas MD Anderson Cancer CenterHoustonTexasUSA
| | - Maya Topf
- Institute of Structural and Molecular Biology, Birkbeck, University College LondonLondonUK
- Centre for Structural Systems Biology, Leibniz‐Institut für Experimentelle VirologieHamburgGermany
| | - Susan E. Tsutakawa
- Molecular Biophysics and Integrated BioimagingLawrence Berkeley National LaboratoryBerkeleyCaliforniaUSA
| | | | - Torsten Schwede
- Biozentrum, University of BaselBaselSwitzerland
- Computational Structural BiologySIB Swiss Institute of BioinformaticsBaselSwitzerland
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15
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Boussau Q, Grandidier E, Makmani Y. [Inhibit for ruling: Acinetobacter baumannii systems against bacteria]. Med Sci (Paris) 2021; 37:948-950. [PMID: 34647887 DOI: 10.1051/medsci/2021160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Quentin Boussau
- École normale supérieure de Lyon, Département de biologie, Master biologie, Lyon, France
| | - Estée Grandidier
- École normale supérieure de Lyon, Département de biologie, Master biologie, Lyon, France
| | - Yazid Makmani
- École normale supérieure de Lyon, Département de biologie, Master biologie, Lyon, France
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Sibinelli-Sousa S, de Araújo-Silva AL, Hespanhol JT, Bayer-Santos E. Revisiting the steps of Salmonella gut infection with a focus on antagonistic interbacterial interactions. FEBS J 2021; 289:4192-4211. [PMID: 34546626 DOI: 10.1111/febs.16211] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 09/12/2021] [Accepted: 09/20/2021] [Indexed: 12/20/2022]
Abstract
A commensal microbial community is established in the mammalian gut during its development, and these organisms protect the host against pathogenic invaders. The hallmark of noninvasive Salmonella gut infection is the induction of inflammation via effector proteins secreted by the type III secretion system, which modulate host responses to create a new niche in which the pathogen can overcome the colonization resistance imposed by the microbiota. Several studies have shown that endogenous microbes are important to control Salmonella infection by competing for resources. However, there is limited information about antimicrobial mechanisms used by commensals and pathogens during these in vivo disputes for niche control. This review aims to revisit the steps that Salmonella needs to overcome during gut colonization-before and after the induction of inflammation-to achieve an effective infection. We focus on a series of reported and hypothetical antagonistic interbacterial interactions in which both contact-independent and contact-dependent mechanisms might define the outcome of the infection.
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Affiliation(s)
| | | | - Julia Takuno Hespanhol
- Departamento de Microbiologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, Brazil
| | - Ethel Bayer-Santos
- Departamento de Microbiologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, Brazil
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17
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Sudan S, Flick R, Nong L, Li J. Potential Probiotic Bacillus subtilis Isolated from a Novel Niche Exhibits Broad Range Antibacterial Activity and Causes Virulence and Metabolic Dysregulation in Enterotoxic E. coli. Microorganisms 2021; 9:1483. [PMID: 34361918 PMCID: PMC8307078 DOI: 10.3390/microorganisms9071483] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2021] [Revised: 07/06/2021] [Accepted: 07/07/2021] [Indexed: 12/12/2022] Open
Abstract
Microbial life in extreme environments, such as deserts and deep oceans, is thought to have evolved to overcome constraints of nutrient availability, temperature, and suboptimal hygiene environments. Isolation of probiotic bacteria from such niche may provide a competitive edge over traditional probiotics. Here, we tested the survival, safety, and antimicrobial effect of a recently isolated and potential novel strain of Bacillus subtilis (CP9) from desert camel in vitro. Antimicrobial assays were performed via radial diffusion, agar spot, and co-culture assays. Cytotoxic analysis was performed using pig intestinal epithelial cells (IPEC-J2). Real time-PCR was performed for studying the effect on ETEC virulence genes and metabolomic analysis was performed using LC-MS. The results showed that CP9 cells were viable in varied bile salts and in low pH environments. CP9 showed no apparent cytotoxicity in IPEC-J2 cells. CP9 displayed significant bactericidal effect against Enterotoxic E. coli (ETEC), Salmonella Typhimurium, and Methicillin-resistant Staphylococcus aureus (MRSA) in a contact inhibitory fashion. CP9 reduced the expression of ETEC virulent genes during a 5 h co-culture. Additionally, a unique emergent metabolic signature in co-culture samples was observed by LC-MS analysis. Our findings indicate that CP9 exhibits a strong antibacterial property and reveals potential mechanisms behind.
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Affiliation(s)
- Sudhanshu Sudan
- Department of Animal Biosciences, University of Guelph, Guelph, ON N1G 2W1, Canada;
| | - Robert Flick
- Biozone, Mass Spectrometry and Metabolomics, Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON M5S 3E5, Canada;
| | - Linda Nong
- Department of Integrative Biology, University of Guelph, Guelph, ON N1G 2W1, Canada;
| | - Julang Li
- Department of Animal Biosciences, University of Guelph, Guelph, ON N1G 2W1, Canada;
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18
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Study of the Antimicrobial Potential of Bacteria found in Natural Resources. JOURNAL OF PURE AND APPLIED MICROBIOLOGY 2021. [DOI: 10.22207/jpam.15.2.28] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Bacteriocins are of great interest as potential antimicrobial agents against various types of bacteria, fungi, and viruses. Isolates of microorganisms derived from natural sources were used in the current study, including lactic acid bacteria and other antagonistic microorganisms. The species of the microorganisms were determined using 16S rDNA and ITS nrDNA analyses. E. coli, S. enterica, S. aureus, P. aeruginosa, B. mycoides, A. faecalis, P. vulgaris, S. flexneri , L. monocytogenes, C. albicans, A. flavus, and P. citrinum were used as pathogenic and opportunistic strains. It was found that 11 strains of antagonistic microorganisms have significant antimicrobial activity against all pathogenic and opportunistic microorganisms. The antimicrobial properties of these microorganisms are currently under study.
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