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Golaz D, Papenfuhs CK, Bellés-Sancho P, Eberl L, Egli M, Pessi G. RNA-seq analysis in simulated microgravity unveils down-regulation of the beta-rhizobial siderophore phymabactin. NPJ Microgravity 2024; 10:44. [PMID: 38570513 PMCID: PMC10991261 DOI: 10.1038/s41526-024-00391-7] [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] [Accepted: 03/25/2024] [Indexed: 04/05/2024] Open
Abstract
Exploiting the symbiotic interaction between crops and nitrogen-fixing bacteria is a simple and ecological method to promote plant growth in prospective extraterrestrial human outposts. In this study, we performed an RNA-seq analysis to investigate the adaptation of the legume symbiont Paraburkholderia phymatum STM815T to simulated microgravity (s0-g) at the transcriptome level. The results revealed a drastic effect on gene expression, with roughly 23% of P. phymatum genes being differentially regulated in s0-g. Among those, 951 genes were upregulated and 858 downregulated in the cells grown in s0-g compared to terrestrial gravity (1 g). Several genes involved in posttranslational modification, protein turnover or chaperones encoding were upregulated in s0-g, while those involved in translation, ribosomal structure and biosynthesis, motility or inorganic ions transport were downregulated. Specifically, the whole phm gene cluster, previously bioinformatically predicted to be involved in the production of a hypothetical malleobactin-like siderophore, phymabactin, was 20-fold downregulated in microgravity. By constructing a mutant strain (ΔphmJK) we confirmed that the phm gene cluster codes for the only siderophore secreted by P. phymatum as assessed by the complete lack of iron chelating activity of the P. phymatum ΔphmJK mutant on chrome azurol S (CAS) agar plates. These results not only provide a deeper understanding of the physiology of symbiotic organisms exposed to space-like conditions, but also increase our knowledge of iron acquisition mechanisms in rhizobia.
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Affiliation(s)
- Daphné Golaz
- Department of Plant and Microbial biology, University of Zurich, Zurich, Switzerland
| | - Chad K Papenfuhs
- Department of Plant and Microbial biology, University of Zurich, Zurich, Switzerland
| | - Paula Bellés-Sancho
- Department of Plant and Microbial biology, University of Zurich, Zurich, Switzerland
| | - Leo Eberl
- Department of Plant and Microbial biology, University of Zurich, Zurich, Switzerland
| | - Marcel Egli
- School of Engineering and Architecture, Institute of Medical Engineering, Space Biology Group, Lucerne University of Applied Sciences and Arts, Hergiswil, Switzerland
- National Center for Biomedical Research in Space, Innovation Cluster Space and Aviation, University of Zurich, Zurich, Switzerland
| | - Gabriella Pessi
- Department of Plant and Microbial biology, University of Zurich, Zurich, Switzerland.
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Granada Agudelo M, Ruiz B, Capela D, Remigi P. The role of microbial interactions on rhizobial fitness. FRONTIERS IN PLANT SCIENCE 2023; 14:1277262. [PMID: 37877089 PMCID: PMC10591227 DOI: 10.3389/fpls.2023.1277262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Accepted: 09/22/2023] [Indexed: 10/26/2023]
Abstract
Rhizobia are soil bacteria that can establish a nitrogen-fixing symbiosis with legume plants. As horizontally transmitted symbionts, the life cycle of rhizobia includes a free-living phase in the soil and a plant-associated symbiotic phase. Throughout this life cycle, rhizobia are exposed to a myriad of other microorganisms that interact with them, modulating their fitness and symbiotic performance. In this review, we describe the diversity of interactions between rhizobia and other microorganisms that can occur in the rhizosphere, during the initiation of nodulation, and within nodules. Some of these rhizobia-microbe interactions are indirect, and occur when the presence of some microbes modifies plant physiology in a way that feeds back on rhizobial fitness. We further describe how these interactions can impose significant selective pressures on rhizobia and modify their evolutionary trajectories. More extensive investigations on the eco-evolutionary dynamics of rhizobia in complex biotic environments will likely reveal fascinating new aspects of this well-studied symbiotic interaction and provide critical knowledge for future agronomical applications.
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Affiliation(s)
- Margarita Granada Agudelo
- Laboratoire des Interactions Plantes Microbes Environnement (LIPME), Université de Toulouse, INRAE, CNRS, Castanet-Tolosan, France
| | - Bryan Ruiz
- Laboratoire des Interactions Plantes Microbes Environnement (LIPME), Université de Toulouse, INRAE, CNRS, Castanet-Tolosan, France
| | - Delphine Capela
- Laboratoire des Interactions Plantes Microbes Environnement (LIPME), Université de Toulouse, INRAE, CNRS, Castanet-Tolosan, France
| | - Philippe Remigi
- Laboratoire des Interactions Plantes Microbes Environnement (LIPME), Université de Toulouse, INRAE, CNRS, Castanet-Tolosan, France
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3
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Goffredi SK, Panossian B, Brzechffa C, Field N, King C, Moggioli G, Rouse GW, Martín-Durán JM, Henry LM. A dynamic epibiont community associated with the bone-eating polychaete genus Osedax. mBio 2023; 14:e0314022. [PMID: 37382438 PMCID: PMC10470745 DOI: 10.1128/mbio.03140-22] [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: 11/08/2022] [Accepted: 05/08/2023] [Indexed: 06/30/2023] Open
Abstract
Osedax, the deep-sea annelid found at sunken whalefalls, is known to host Oceanospirillales bacterial endosymbionts intracellularly in specialized roots, which help it feed exclusively on vertebrate bones. Past studies, however, have also made mention of external bacteria on their trunks. During a 14-yr study, we reveal a dynamic, yet persistent, shift of Campylobacterales integrated into the epidermis of Osedax, which change over time as the whale carcass degrades on the sea floor. The Campylobacterales associated with seven species of Osedax, which comprise 67% of the bacterial community on the trunk, appear initially dominated by the genus Arcobacter (at early time points <24 mo), the Sulfurospirillum at intermediate stages (~50 mo), and the Sulfurimonas at later stages (>140 mo) of whale carcass decomposition. Metagenome analysis of the epibiont metabolic capabilities suggests potential for a transition from heterotrophy to autotrophy and differences in their capacity to metabolize oxygen, carbon, nitrogen, and sulfur. Compared to free-living relatives, the Osedax epibiont genomes were enriched in transposable elements, implicating genetic exchange on the host surface, and contained numerous secretions systems with eukaryotic-like protein (ELP) domains, suggesting a long evolutionary history with these enigmatic, yet widely distributed deep-sea worms. IMPORTANCE Symbiotic associations are widespread in nature and we can expect to find them in every type of ecological niche. In the last twenty years, the myriad of functions, interactions and species comprising microbe-host associations has fueled a surge of interest and appreciation for symbiosis. During this 14-year study, we reveal a dynamic population of bacterial epibionts, integrated into the epidermis of 7 species of a deep-sea worm group that feeds exclusively on the remains of marine mammals. The bacterial genomes provide clues of a long evolutionary history with these enigmatic worms. On the host surface, they exchange genes and appear to undergo ecological succession, as the whale carcass habitat degrades over time, similar to what is observed for some free-living communities. These, and other annelid worms are important keystone species for diverse deep-sea environments, yet the role of attached external bacteria in supporting host health has received relatively little attention.
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Affiliation(s)
- Shana K. Goffredi
- Department of Biology, Occidental College, Los Angeles, California, USA
| | - Balig Panossian
- School of Biological and Behavioural Sciences, Queen Mary University of London, London, United Kingdom
| | - Camille Brzechffa
- Department of Biology, Occidental College, Los Angeles, California, USA
| | - Naomi Field
- Department of Biology, Occidental College, Los Angeles, California, USA
| | - Chad King
- Monterey Bay National Marine Sanctuary, Monterey, California, USA
| | - Giacomo Moggioli
- School of Biological and Behavioural Sciences, Queen Mary University of London, London, United Kingdom
| | - Greg W. Rouse
- Scripps Oceanography, University of California, La Jolla, California, USA
| | - José M. Martín-Durán
- School of Biological and Behavioural Sciences, Queen Mary University of London, London, United Kingdom
| | - Lee M. Henry
- School of Biological and Behavioural Sciences, Queen Mary University of London, London, United Kingdom
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Hug S, Heiniger B, Bolli K, Paszti S, Eberl L, Ahrens CH, Pessi G. Paraburkholderia sabiae Uses One Type VI Secretion System (T6SS-1) as a Powerful Weapon against Notorious Plant Pathogens. Microbiol Spectr 2023; 11:e0162223. [PMID: 37439699 PMCID: PMC10434147 DOI: 10.1128/spectrum.01622-23] [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: 04/18/2023] [Accepted: 06/21/2023] [Indexed: 07/14/2023] Open
Abstract
Paraburkholderia sabiae LMG24235 is a nitrogen-fixing betaproteobacterium originally isolated from a root nodule of Mimosa caesalpiniifolia in Brazil. We show here that this strain effectively kills strains from several bacterial families (Burkholderiaceae, Pseudomonadaceae, Enterobacteriaceae) which include important plant pathogens in a contact-dependent manner. De novo assembly of the first complete genome of P. sabiae using long sequencing reads and subsequent annotation revealed two gene clusters predicted to encode type VI secretion systems (T6SS), which we named T6SS-1 and T6SS-3 according to previous classification methods (G. Shalom, J. G. Shaw, and M. S. Thomas, Microbiology, 153:2689-2699, 2007, https://doi.org/10.1099/mic.0.2007/006585-0). We created P. sabiae with mutations in each of the two T6SS gene clusters that abrogated their function, and the T6SS-1 mutant was no longer able to outcompete other strains in a contact-dependent manner. Notably, our analysis revealed that T6SS-1 is essential for competition against several important plant pathogens in vitro, including Burkholderia plantarii, Ralstonia solanacearum, Pseudomonas syringae, and Pectobacterium carotovorum. The 9-log reduction in P. syringae cells in the presence of P. sabiae was particularly remarkable. Importantly, in an in vivo assay, P. sabiae was able to protect potato tubers from bacterial soft rot disease caused by P. carotovorum, and this protection was partly dependent on T6SS-1. IMPORTANCE Rhizobia often display additional beneficial traits such as the production of plant hormones and the acquisition of limited essential nutrients that improve plant growth and enhance plant yields. Here, we show that the rhizobial strain P. sabiae antagonizes important phytopathogens such as P. carotovorum, P. syringae, and R. solanacearum and that this effect is due to contact-dependent killing mediated by one of two T6SS systems identified in the complete, de novo assembled genome sequence of P. sabiae. Importantly, co-inoculation of Solanum tuberosum tubers with P. sabiae also resulted in a drastic reduction of soft rot caused by P. carotovorum in an in vivo model system. This result highlights the protective potential of P. sabiae against important bacterial plant diseases, which makes it a valuable candidate for application as a biocontrol agent. It also emphasizes the particular potential of rhizobial inoculants that combine several beneficial effects such as plant growth promotion and biocontrol for sustainable agriculture.
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Affiliation(s)
- Sebastian Hug
- Department of Plant and Microbial Biology, University of Zürich, Zurich, Switzerland
| | - Benjamin Heiniger
- Agroscope – Molecular Ecology, Swiss Institute of Bioinformatics, Zurich, Switzerland
| | - Kim Bolli
- Department of Plant and Microbial Biology, University of Zürich, Zurich, Switzerland
| | - Sarah Paszti
- Department of Plant and Microbial Biology, University of Zürich, Zurich, Switzerland
| | - Leo Eberl
- Department of Plant and Microbial Biology, University of Zürich, Zurich, Switzerland
| | - Christian H. Ahrens
- Agroscope – Molecular Ecology, Swiss Institute of Bioinformatics, Zurich, Switzerland
| | - Gabriella Pessi
- Department of Plant and Microbial Biology, University of Zürich, Zurich, Switzerland
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De Sousa BFS, Domingo-Serrano L, Salinero-Lanzarote A, Palacios JM, Rey L. The T6SS-Dependent Effector Re78 of Rhizobium etli Mim1 Benefits Bacterial Competition. BIOLOGY 2023; 12:678. [PMID: 37237492 PMCID: PMC10215855 DOI: 10.3390/biology12050678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Revised: 04/26/2023] [Accepted: 05/02/2023] [Indexed: 05/28/2023]
Abstract
The genes of the type VI secretion system (T6SS) from Rhizobium etli Mim1 (ReMim1) that contain possible effectors can be divided into three modules. The mutants in them indicated that they are not required for effective nodulation with beans. To analyze T6SS expression, a putative promoter region between the tssA and tssH genes was fused in both orientations to a reporter gene. Both fusions are expressed more in free living than in symbiosis. When the module-specific genes were studied using RT-qPCR, a low expression was observed in free living and in symbiosis, which was clearly lower than the structural genes. The secretion of Re78 protein from the T6SS gene cluster was dependent on the presence of an active T6SS. Furthermore, the expression of Re78 and Re79 proteins in E. coli without the ReMim1 nanosyringe revealed that these proteins behave as a toxic effector/immunity protein pair (E/I). The harmful action of Re78, whose mechanism is still unknown, would take place in the periplasmic space of the target cell. The deletion of this ReMim1 E/I pair resulted in reduced competitiveness for bean nodule occupancy and in lower survival in the presence of the wild-type strain.
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Affiliation(s)
- Bruna Fernanda Silva De Sousa
- Centro de Biotecnología y Genómica de Plantas, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA/CSIC), Campus de Montegancedo UPM, Universidad Politécnica de Madrid (UPM), 28223 Pozuelo de Alarcón, Spain; (B.F.S.D.S.)
| | - Lucía Domingo-Serrano
- Centro de Biotecnología y Genómica de Plantas, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA/CSIC), Campus de Montegancedo UPM, Universidad Politécnica de Madrid (UPM), 28223 Pozuelo de Alarcón, Spain; (B.F.S.D.S.)
| | - Alvaro Salinero-Lanzarote
- Centro de Biotecnología y Genómica de Plantas, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA/CSIC), Campus de Montegancedo UPM, Universidad Politécnica de Madrid (UPM), 28223 Pozuelo de Alarcón, Spain; (B.F.S.D.S.)
| | - José Manuel Palacios
- Centro de Biotecnología y Genómica de Plantas, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA/CSIC), Campus de Montegancedo UPM, Universidad Politécnica de Madrid (UPM), 28223 Pozuelo de Alarcón, Spain; (B.F.S.D.S.)
- Departamento de Biotecnología y Biología Vegetal, ETSI Agronómica Alimentaria y de Biosistemas, Universidad Politécnica de Madrid, 28040 Madrid, Spain
| | - Luis Rey
- Centro de Biotecnología y Genómica de Plantas, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA/CSIC), Campus de Montegancedo UPM, Universidad Politécnica de Madrid (UPM), 28223 Pozuelo de Alarcón, Spain; (B.F.S.D.S.)
- Departamento de Biotecnología y Biología Vegetal, ETSI Agronómica Alimentaria y de Biosistemas, Universidad Politécnica de Madrid, 28040 Madrid, Spain
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6
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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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7
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Tighilt L, Boulila F, De Sousa BFS, Giraud E, Ruiz-Argüeso T, Palacios JM, Imperial J, Rey L. The Bradyrhizobium Sp. LmicA16 Type VI Secretion System Is Required for Efficient Nodulation of Lupinus Spp. MICROBIAL ECOLOGY 2022; 84:844-855. [PMID: 34697646 DOI: 10.1007/s00248-021-01892-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Accepted: 09/30/2021] [Indexed: 05/06/2023]
Abstract
Many bacteria of the genus Bradyrhizobium are capable of inducing nodules in legumes. In this work, the importance of a type VI secretion system (T6SS) in a symbiotic strain of the genus Bradyrhizobium is described. T6SS of Bradyrhizobium sp. LmicA16 (A16) is necessary for efficient nodulation with Lupinus micranthus and Lupinus angustifolius. A mutant in the gene vgrG, coding for a component of the T6SS nanostructure, induced less nodules and smaller plants than the wild-type (wt) strain and was less competitive when co-inoculated with the wt strain. A16 T6SS genes are organized in a 26-kb DNA region in two divergent gene clusters of nine genes each. One of these genes codes for a protein (Tsb1) of unknown function but containing a methyltransferase domain. A tsb1 mutant showed an intermediate symbiotic phenotype regarding vgrG mutant and higher mucoidity than the wt strain in free-living conditions. T6SS promoter fusions to the lacZ reporter indicate expression in nodules but not in free-living cells grown in different media and conditions. The analysis of nodule structure revealed that the level of nodule colonization was significantly reduced in the mutants with respect to the wt strain.
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Affiliation(s)
- L Tighilt
- Laboratoire d'Ecologie Microbienne, Faculté Des Sciences de La Nature Et de La Vie, Université de Bejaia, 06000, Bejaia, Algeria
- Centro de Biotecnología Y Genómica de Plantas, Universidad Politécnica de Madrid (UPM), Instituto Nacional de Investigación Y Tecnología Agraria Y Alimentaria (INIA), Campus de Montegancedo, 28223, Madrid, Spain
| | - F Boulila
- Laboratoire d'Ecologie Microbienne, Faculté Des Sciences de La Nature Et de La Vie, Université de Bejaia, 06000, Bejaia, Algeria
| | - B F S De Sousa
- Centro de Biotecnología Y Genómica de Plantas, Universidad Politécnica de Madrid (UPM), Instituto Nacional de Investigación Y Tecnología Agraria Y Alimentaria (INIA), Campus de Montegancedo, 28223, Madrid, Spain
- Departamento de Biotecnología Y Biología Vegetal, ETSI Agronómica, Alimentaria Y de Biosistemas, Universidad Politécnica de Madrid, 28040, Madrid, Spain
| | - E Giraud
- IRD, Laboratoire Des Symbioses Tropicales Et Méditerranéennes (LSTM), UMR IRD/SupAgro/INRA/Université de Montpellier/CIRAD, TA-A82/J-Campus International de Baillarguet, 34398Cedex 5, Montpellier, France
| | - T Ruiz-Argüeso
- Centro de Biotecnología Y Genómica de Plantas, Universidad Politécnica de Madrid (UPM), Instituto Nacional de Investigación Y Tecnología Agraria Y Alimentaria (INIA), Campus de Montegancedo, 28223, Madrid, Spain
- Departamento de Biotecnología Y Biología Vegetal, ETSI Agronómica, Alimentaria Y de Biosistemas, Universidad Politécnica de Madrid, 28040, Madrid, Spain
| | - J M Palacios
- Centro de Biotecnología Y Genómica de Plantas, Universidad Politécnica de Madrid (UPM), Instituto Nacional de Investigación Y Tecnología Agraria Y Alimentaria (INIA), Campus de Montegancedo, 28223, Madrid, Spain
- Departamento de Biotecnología Y Biología Vegetal, ETSI Agronómica, Alimentaria Y de Biosistemas, Universidad Politécnica de Madrid, 28040, Madrid, Spain
| | - J Imperial
- Centro de Biotecnología Y Genómica de Plantas, Universidad Politécnica de Madrid (UPM), Instituto Nacional de Investigación Y Tecnología Agraria Y Alimentaria (INIA), Campus de Montegancedo, 28223, Madrid, Spain
- Instituto de Ciencias Agrarias, CSIC, 28006, Madrid, Spain
| | - L Rey
- Centro de Biotecnología Y Genómica de Plantas, Universidad Politécnica de Madrid (UPM), Instituto Nacional de Investigación Y Tecnología Agraria Y Alimentaria (INIA), Campus de Montegancedo, 28223, Madrid, Spain.
- Departamento de Biotecnología Y Biología Vegetal, ETSI Agronómica, Alimentaria Y de Biosistemas, Universidad Politécnica de Madrid, 28040, Madrid, Spain.
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Cai D, Zhang Z, Feng Z, Song J, Zeng X, Tu Y, Zhao S, Luo X, Sun C, Yang Y, Liu X, Zou Q, Zeng H, Sun H. A lipophilic chitosan-modified self-nanoemulsifying system influencing cellular membrane metabolism enhances antibacterial and anti-biofilm efficacy for multi-drug resistant Pseudomonas aeruginosa wound infection. BIOMATERIALS ADVANCES 2022; 140:213029. [PMID: 36058016 DOI: 10.1016/j.bioadv.2022.213029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Revised: 07/04/2022] [Accepted: 07/10/2022] [Indexed: 06/15/2023]
Abstract
Wound infections, especially infections with multidrug-resistant bacteria, are a serious public health issue worldwide. In addition, the accumulation microbial biofilm of multidrug-resistant Pseudomonas aeruginosa increases the risk and physically obstruct its healing activity at the wound site. Therefore, the development of an eminent agent to control wound infection is urgently needed. Here, we report a novel chitosan (a natural biological macromolecule)-modified self-nanoemulsifying system (CSN) with lipophilic chlorhexidine acetate (CAA, a poorly water-soluble agent) that was designed and prepared using low-energy emulsification methods. We found that CSN displays better antibacterial efficacy, which occurs more quickly than its aqueous solution, in destroying the structure of the bacterial cell membrane and promoting the leakage of nucleic acids, proteins, K+, and Mg2+ from Pseudomonas aeruginosa cells. Importantly, CSN also accelerates skin wound healing after Pseudomonas aeruginosa infection by inhibiting biofilm formation and eradicating mature biofilms. Moreover, the proteomic results suggested that CSN altered membrane permeability and cellular membrane metabolism, allowing more drug molecules to enter the cytosol. Based on these results, this lipophilic self-nanoemulsifying system may be applied in the treatment of skin wounds caused by multidrug-resistant bacteria, especially Pseudomonas aeruginosa.
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Affiliation(s)
- Dingyi Cai
- National Engineering Research Centre of Immunological Products & Department of Microbiology and Biochemical Pharmacy, College of Pharmacy, Third Military Medical University, Chongqing 400038, China
| | - ZeLong Zhang
- National Engineering Research Centre of Immunological Products & Department of Microbiology and Biochemical Pharmacy, College of Pharmacy, Third Military Medical University, Chongqing 400038, China
| | - Ziqi Feng
- National Engineering Research Centre of Immunological Products & Department of Microbiology and Biochemical Pharmacy, College of Pharmacy, Third Military Medical University, Chongqing 400038, China
| | - Jianye Song
- National Engineering Research Centre of Immunological Products & Department of Microbiology and Biochemical Pharmacy, College of Pharmacy, Third Military Medical University, Chongqing 400038, China
| | - Xiaoqiang Zeng
- National Engineering Research Centre of Immunological Products & Department of Microbiology and Biochemical Pharmacy, College of Pharmacy, Third Military Medical University, Chongqing 400038, China
| | - Yatao Tu
- National Engineering Research Centre of Immunological Products & Department of Microbiology and Biochemical Pharmacy, College of Pharmacy, Third Military Medical University, Chongqing 400038, China
| | - Shibo Zhao
- National Engineering Research Centre of Immunological Products & Department of Microbiology and Biochemical Pharmacy, College of Pharmacy, Third Military Medical University, Chongqing 400038, China
| | - Xing Luo
- National Engineering Research Centre of Immunological Products & Department of Microbiology and Biochemical Pharmacy, College of Pharmacy, Third Military Medical University, Chongqing 400038, China
| | - Cun Sun
- National Engineering Research Centre of Immunological Products & Department of Microbiology and Biochemical Pharmacy, College of Pharmacy, Third Military Medical University, Chongqing 400038, China
| | - Yun Yang
- National Engineering Research Centre of Immunological Products & Department of Microbiology and Biochemical Pharmacy, College of Pharmacy, Third Military Medical University, Chongqing 400038, China
| | - Xuesong Liu
- National Engineering Research Centre of Immunological Products & Department of Microbiology and Biochemical Pharmacy, College of Pharmacy, Third Military Medical University, Chongqing 400038, China
| | - Quanming Zou
- National Engineering Research Centre of Immunological Products & Department of Microbiology and Biochemical Pharmacy, College of Pharmacy, Third Military Medical University, Chongqing 400038, China.
| | - Hao Zeng
- National Engineering Research Centre of Immunological Products & Department of Microbiology and Biochemical Pharmacy, College of Pharmacy, Third Military Medical University, Chongqing 400038, China.
| | - Hongwu Sun
- National Engineering Research Centre of Immunological Products & Department of Microbiology and Biochemical Pharmacy, College of Pharmacy, Third Military Medical University, Chongqing 400038, China.
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9
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Quantitative Real-Time PCR Assay for the Detection of Pectobacterium parmentieri, a Causal Agent of Potato Soft Rot. PLANTS 2021; 10:plants10091880. [PMID: 34579412 PMCID: PMC8468878 DOI: 10.3390/plants10091880] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Accepted: 09/08/2021] [Indexed: 11/17/2022]
Abstract
Pectobacterium parmentieri is a plant-pathogenic bacterium, recently attributed as a separate species, which infects potatoes, causing soft rot in tubers. The distribution of P. parmentieri seems to be global, although the bacterium tends to be accommodated to moderate climates. Fast and accurate detection systems for this pathogen are needed to study its biology and to identify latent infection in potatoes and other plant hosts. The current paper reports on the development of a specific and sensitive detection protocol based on a real-time PCR with a TaqMan probe for P. parmentieri, and its evaluation. In sensitivity assays, the detection threshold of this protocol was 102 cfu/mL on pure bacterial cultures and 102–103 cfu/mL on plant material. The specificity of the protocol was evaluated against P. parmentieri and more than 100 strains of potato-associated species of Pectobacterium and Dickeya. No cross-reaction with the non-target bacterial species, or loss of sensitivity, was observed. This specific and sensitive diagnostic tool may reveal a wider distribution and host range for P. parmentieri and will expand knowledge of the life cycle and environmental preferences of this pathogen.
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10
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Mendoza-Suárez M, Andersen SU, Poole PS, Sánchez-Cañizares C. Competition, Nodule Occupancy, and Persistence of Inoculant Strains: Key Factors in the Rhizobium-Legume Symbioses. FRONTIERS IN PLANT SCIENCE 2021; 12:690567. [PMID: 34489993 PMCID: PMC8416774 DOI: 10.3389/fpls.2021.690567] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2021] [Accepted: 07/19/2021] [Indexed: 05/06/2023]
Abstract
Biological nitrogen fixation by Rhizobium-legume symbioses represents an environmentally friendly and inexpensive alternative to the use of chemical nitrogen fertilizers in legume crops. Rhizobial inoculants, applied frequently as biofertilizers, play an important role in sustainable agriculture. However, inoculants often fail to compete for nodule occupancy against native rhizobia with inferior nitrogen-fixing abilities, resulting in low yields. Strains with excellent performance under controlled conditions are typically selected as inoculants, but the rates of nodule occupancy compared to native strains are rarely investigated. Lack of persistence in the field after agricultural cycles, usually due to the transfer of symbiotic genes from the inoculant strain to naturalized populations, also limits the suitability of commercial inoculants. When rhizobial inoculants are based on native strains with a high nitrogen fixation ability, they often have superior performance in the field due to their genetic adaptations to the local environment. Therefore, knowledge from laboratory studies assessing competition and understanding how diverse strains of rhizobia behave, together with assays done under field conditions, may allow us to exploit the effectiveness of native populations selected as elite strains and to breed specific host cultivar-rhizobial strain combinations. Here, we review current knowledge at the molecular level on competition for nodulation and the advances in molecular tools for assessing competitiveness. We then describe ongoing approaches for inoculant development based on native strains and emphasize future perspectives and applications using a multidisciplinary approach to ensure optimal performance of both symbiotic partners.
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Affiliation(s)
| | - Stig U. Andersen
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
| | - Philip S. Poole
- Department of Plant Sciences, University of Oxford, Oxford, United Kingdom
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11
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Marian M, Fujikawa T, Shimizu M. Genome analysis provides insights into the biocontrol ability of Mitsuaria sp. strain TWR114. Arch Microbiol 2021; 203:3373-3388. [PMID: 33880605 DOI: 10.1007/s00203-021-02327-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Revised: 04/07/2021] [Accepted: 04/09/2021] [Indexed: 12/31/2022]
Abstract
Mitsuaria sp. TWR114 is a biocontrol agent against tomato bacterial wilt (TBW). We aimed to gain genomic insights relevant to the biocontrol mechanisms and colonization ability of this strain. The draft genome size was found to be 5,632,523 bp, with a GC content of 69.5%, assembled into 1144 scaffolds. Genome annotation predicted a total of 4675 protein coding sequences (CDSs), 914 pseudogenes, 49 transfer RNAs, 3 noncoding RNAs, and 2 ribosomal RNAs. Genome analysis identified multiple CDSs associated with various pathways for the metabolism and transport of amino acids and carbohydrates, motility and chemotactic capacities, protection against stresses (oxidative, antibiotic, and phage), production of secondary metabolites, peptidases, quorum-quenching enzymes, and indole-3-acetic acid, as well as protein secretion systems and their related appendages. The genome resource will extend our understanding of the genomic features related to TWR114's biocontrol and colonization abilities and facilitate its development as a new biopesticide against TBW.
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Affiliation(s)
- Malek Marian
- Faculty of Applied Biological Sciences, Gifu University, Gifu, 501-1193, Japan.,College of Agriculture, Ibaraki University, Ami, Inashiki, Ibaraki, 300-0393, Japan
| | - Takashi Fujikawa
- Institute of Fruit Tree and Tea Science, National Agriculture and Food Research Organization (NARO), Tsukuba, Ibaraki, 305-8605, Japan
| | - Masafumi Shimizu
- Faculty of Applied Biological Sciences, Gifu University, Gifu, 501-1193, Japan.
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12
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Bellés-Sancho P, Lardi M, Liu Y, Hug S, Pinto-Carbó MA, Zamboni N, Pessi G. Paraburkholderia phymatum Homocitrate Synthase NifV Plays a Key Role for Nitrogenase Activity during Symbiosis with Papilionoids and in Free-Living Growth Conditions. Cells 2021; 10:cells10040952. [PMID: 33924023 PMCID: PMC8073898 DOI: 10.3390/cells10040952] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Revised: 04/14/2021] [Accepted: 04/17/2021] [Indexed: 12/29/2022] Open
Abstract
Homocitrate is an essential component of the iron-molybdenum cofactor of nitrogenase, the bacterial enzyme that catalyzes the reduction of dinitrogen (N2) to ammonia. In nitrogen-fixing and nodulating alpha-rhizobia, homocitrate is usually provided to bacteroids in root nodules by their plant host. In contrast, non-nodulating free-living diazotrophs encode the homocitrate synthase (NifV) and reduce N2 in nitrogen-limiting free-living conditions. Paraburkholderia phymatum STM815 is a beta-rhizobial strain, which can enter symbiosis with a broad range of legumes, including papilionoids and mimosoids. In contrast to most alpha-rhizobia, which lack nifV, P. phymatum harbors a copy of nifV on its symbiotic plasmid. We show here that P. phymatum nifV is essential for nitrogenase activity both in root nodules of papilionoid plants and in free-living growth conditions. Notably, nifV was dispensable in nodules of Mimosa pudica despite the fact that the gene was highly expressed during symbiosis with all tested papilionoid and mimosoid plants. A metabolome analysis of papilionoid and mimosoid root nodules infected with the P. phymatum wild-type strain revealed that among the approximately 400 measured metabolites, homocitrate and other metabolites involved in lysine biosynthesis and degradation have accumulated in all plant nodules compared to uninfected roots, suggesting an important role of these metabolites during symbiosis.
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Affiliation(s)
- Paula Bellés-Sancho
- Department of Plant and Microbial Biology, University of Zürich, CH-8057 Zürich, Switzerland; (P.B.-S.); (M.L.); (Y.L.); (S.H.); (M.A.P.-C.)
| | - Martina Lardi
- Department of Plant and Microbial Biology, University of Zürich, CH-8057 Zürich, Switzerland; (P.B.-S.); (M.L.); (Y.L.); (S.H.); (M.A.P.-C.)
| | - Yilei Liu
- Department of Plant and Microbial Biology, University of Zürich, CH-8057 Zürich, Switzerland; (P.B.-S.); (M.L.); (Y.L.); (S.H.); (M.A.P.-C.)
| | - Sebastian Hug
- Department of Plant and Microbial Biology, University of Zürich, CH-8057 Zürich, Switzerland; (P.B.-S.); (M.L.); (Y.L.); (S.H.); (M.A.P.-C.)
| | - Marta Adriana Pinto-Carbó
- Department of Plant and Microbial Biology, University of Zürich, CH-8057 Zürich, Switzerland; (P.B.-S.); (M.L.); (Y.L.); (S.H.); (M.A.P.-C.)
| | - Nicola Zamboni
- ETH Zürich, Institute of Molecular Systems Biology, CH-8093 Zürich, Switzerland;
| | - Gabriella Pessi
- Department of Plant and Microbial Biology, University of Zürich, CH-8057 Zürich, Switzerland; (P.B.-S.); (M.L.); (Y.L.); (S.H.); (M.A.P.-C.)
- Correspondence: ; Tel.: +41-44-63-52904
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13
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Abstract
Rhizobia are a phylogenetically diverse group of soil bacteria that engage in mutualistic interactions with legume plants. Although specifics of the symbioses differ between strains and plants, all symbioses ultimately result in the formation of specialized root nodule organs which host the nitrogen-fixing microsymbionts called bacteroids. Inside nodules, bacteroids encounter unique conditions that necessitate global reprogramming of physiological processes and rerouting of their metabolism. Decades of research have addressed these questions using genetics, omics approaches, and more recently computational modelling. Here we discuss the common adaptations of rhizobia to the nodule environment that define the core principles of bacteroid functioning. All bacteroids are growth-arrested and perform energy-intensive nitrogen fixation fueled by plant-provided C4-dicarboxylates at nanomolar oxygen levels. At the same time, bacteroids are subject to host control and sanctioning that ultimately determine their fitness and have fundamental importance for the evolution of a stable mutualistic relationship.
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14
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Hug S, Liu Y, Heiniger B, Bailly A, Ahrens CH, Eberl L, Pessi G. Differential Expression of Paraburkholderia phymatum Type VI Secretion Systems (T6SS) Suggests a Role of T6SS-b in Early Symbiotic Interaction. FRONTIERS IN PLANT SCIENCE 2021; 12:699590. [PMID: 34394152 PMCID: PMC8356804 DOI: 10.3389/fpls.2021.699590] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Accepted: 06/28/2021] [Indexed: 05/06/2023]
Abstract
Paraburkholderia phymatum STM815, a rhizobial strain of the Burkholderiaceae family, is able to nodulate a broad range of legumes including the agriculturally important Phaseolus vulgaris (common bean). P. phymatum harbors two type VI Secretion Systems (T6SS-b and T6SS-3) in its genome that contribute to its high interbacterial competitiveness in vitro and in infecting the roots of several legumes. In this study, we show that P. phymatum T6SS-b is found in the genomes of several soil-dwelling plant symbionts and that its expression is induced by the presence of citrate and is higher at 20/28°C compared to 37°C. Conversely, T6SS-3 shows homologies to T6SS clusters found in several pathogenic Burkholderia strains, is more prominently expressed with succinate during stationary phase and at 37°C. In addition, T6SS-b expression was activated in the presence of germinated seeds as well as in P. vulgaris and Mimosa pudica root nodules. Phenotypic analysis of selected deletion mutant strains suggested a role of T6SS-b in motility but not at later stages of the interaction with legumes. In contrast, the T6SS-3 mutant was not affected in any of the free-living and symbiotic phenotypes examined. Thus, P. phymatum T6SS-b is potentially important for the early infection step in the symbiosis with legumes.
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Affiliation(s)
- Sebastian Hug
- Department of Plant and Microbial Biology, University of Zurich, Zurich, Switzerland
| | - Yilei Liu
- Department of Plant and Microbial Biology, University of Zurich, Zurich, Switzerland
| | - Benjamin Heiniger
- Agroscope, Research Group Molecular Diagnostics, Genomics and Bioinformatics, Swiss Institute of Bioinformatics, Wädenswil, Switzerland
| | - Aurélien Bailly
- Department of Plant and Microbial Biology, University of Zurich, Zurich, Switzerland
| | - Christian H. Ahrens
- Agroscope, Research Group Molecular Diagnostics, Genomics and Bioinformatics, Swiss Institute of Bioinformatics, Wädenswil, Switzerland
| | - Leo Eberl
- Department of Plant and Microbial Biology, University of Zurich, Zurich, Switzerland
| | - Gabriella Pessi
- Department of Plant and Microbial Biology, University of Zurich, Zurich, Switzerland
- *Correspondence: Gabriella Pessi,
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15
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Paraburkholderia phymatum STM815 σ54 Controls Utilization of Dicarboxylates, Motility, and T6SS-b Expression. NITROGEN 2020. [DOI: 10.3390/nitrogen1020008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Rhizobia have two major life styles, one as free-living bacteria in the soil, and the other as bacteroids within the root/stem nodules of host legumes where they convert atmospheric nitrogen into ammonia. In the soil, rhizobia have to cope with changing and sometimes stressful environmental conditions, such as nitrogen limitation. In the beta-rhizobial strain Paraburkholderia phymatum STM815, the alternative sigma factor σ54 (or RpoN) has recently been shown to control nitrogenase activity during symbiosis with Phaseolus vulgaris. In this study, we determined P. phymatum’s σ54 regulon under nitrogen-limited free-living conditions. Among the genes significantly downregulated in the absence of σ54, we found a C4-dicarboxylate carrier protein (Bphy_0225), a flagellar biosynthesis cluster (Bphy_2926-64), and one of the two type VI secretion systems (T6SS-b) present in the P. phymatum STM815 genome (Bphy_5978-97). A defined σ54 mutant was unable to grow on C4 dicarboxylates as sole carbon source and was less motile compared to the wild-type strain. Both defects could be complemented by introducing rpoNin trans. Using promoter reporter gene fusions, we also confirmed that the expression of the T6SS-b cluster is regulated by σ54. Accordingly, we show that σ54 affects in vitro competitiveness of P. phymatum STM815 against Paraburkholderia diazotrophica.
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16
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Louvado A, Coelho FJRC, Palma M, Tavares LC, Ozorio ROA, Magnoni L, Viegas I, Gomes NCM. Effect of glycerol feed-supplementation on seabass metabolism and gut microbiota. Appl Microbiol Biotechnol 2020; 104:8439-8453. [PMID: 32845369 DOI: 10.1007/s00253-020-10809-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Revised: 07/20/2020] [Accepted: 08/02/2020] [Indexed: 12/22/2022]
Abstract
Dietary glycerol supplementation in aquaculture feed is seen as an alternative and inexpensive way to fuel fish metabolism, attenuate metabolic utilization of dietary proteins and, subsequently, reduce nitrogen excretion. In this study, we evaluated the impact of dietary glycerol supplementation on nitrogen excretion of European seabass (Dicentrarchus labrax) and its effects on metabolite profile and bacterial community composition of gut digesta. These effects were evaluated in a 60-day trial with fish fed diets supplemented with 2.5% or 5% (w/w) refined glycerol and without glycerol supplementation. Nuclear magnetic resonance spectroscopy and high-throughput 16S rRNA gene sequencing were used to characterize the effects of glycerol supplementation on digesta metabolite and bacterial community composition of 6-h postprandial fish. Our results showed that ammonia excretion was not altered by dietary glycerol supplementation, and the highest glycerol dosage was associated with significant increases in amino acids and a decrease of ergogenic creatine in digesta metabolome. Concomitantly, significant decreases in putative amino acid degradation pathways were detected in the predicted metagenome analysis, suggesting a metabolic shift. Taxon-specific analysis revealed significant increases in abundance of some specific genera (e.g., Burkholderia and Vibrio) and bacterial diversity. Overall, our results indicate glycerol supplementation may decrease amino acid catabolism without adversely affecting fish gut bacterial communities.Key points• Glycerol can be an inexpensive and energetic alternative in fish feed formulations.• Glycerol did not affect nitrogen excretion and gut bacteriome composition.• Glycerol reduced uptake of amino acids and increased uptake of ergogenic creatine.• Glycerol reduced putative amino acid degradation pathways in predicted metagenome.
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Affiliation(s)
- A Louvado
- Department of Biology & CESAM, University of Aveiro, 3810-193, Aveiro, Portugal
| | - F J R C Coelho
- Department of Biology & CESAM, University of Aveiro, 3810-193, Aveiro, Portugal
| | - M Palma
- University of Coimbra, Centre for Functional Ecology, Department of Life Sciences, 3000-456, Coimbra, Portugal
| | - L C Tavares
- Centre for Neuroscience and Cell Biology, University of Coimbra, 3004-517, Coimbra, Portugal
| | - R O A Ozorio
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), University of Porto, Matosinhos, Portugal
| | - L Magnoni
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), University of Porto, Matosinhos, Portugal
| | - I Viegas
- University of Coimbra, Centre for Functional Ecology, Department of Life Sciences, 3000-456, Coimbra, Portugal.,Centre for Neuroscience and Cell Biology, University of Coimbra, 3004-517, Coimbra, Portugal
| | - N C M Gomes
- Department of Biology & CESAM, University of Aveiro, 3810-193, Aveiro, Portugal.
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17
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Barretto LAF, Fowler CC. Identification of A Putative T6SS Immunity Islet in Salmonella Typhi. Pathogens 2020; 9:pathogens9070559. [PMID: 32664482 PMCID: PMC7400221 DOI: 10.3390/pathogens9070559] [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: 06/19/2020] [Revised: 07/05/2020] [Accepted: 07/06/2020] [Indexed: 12/19/2022] Open
Abstract
Typhoid fever is a major global health problem and is the result of systemic infections caused by the human-adapted bacterial pathogen Salmonella enterica serovar Typhi (S. Typhi). The pathology underlying S. Typhi infections significantly differ from infections caused by broad host range serovars of the same species, which are a common cause of gastroenteritis. Accordingly, identifying S. Typhi genetic factors that impart functionality absent from broad host range serovars offers insights into its unique biology. Here, we used an in-silico approach to explore the function of an uncharacterized 14-gene S. Typhi genomic islet. Our results indicated that this islet was specific to the S. enterica species, where it was encoded by the Typhi and Paratyphi A serovars, but was generally absent from non-typhoidal serovars. Evidence was gathered using comparative genomics and sequence analysis tools, and indicated that this islet was comprised of Type VI secretion system (T6SS) and contact-dependent growth inhibition (CDI) genes, the majority of which appeared to encode orphan immunity proteins that protected against the activities of effectors and toxins absent from the S. Typhi genome. We herein propose that this islet represents an immune system that protects S. Typhi against competing bacteria within the human gut.
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18
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Salinero-Lanzarote A, Pacheco-Moreno A, Domingo-Serrano L, Durán D, Ormeño-Orrillo E, Martínez-Romero E, Albareda M, Palacios JM, Rey L. The Type VI secretion system of Rhizobium etli Mim1 has a positive effect in symbiosis. FEMS Microbiol Ecol 2020; 95:5449006. [PMID: 30977796 DOI: 10.1093/femsec/fiz054] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Accepted: 04/11/2019] [Indexed: 12/18/2022] Open
Abstract
The Type VI secretion systems (T6SSs) allow bacteria to translocate effector proteins to other bacteria or to eukaryotic cells. However, little is known about the role of T6SS in endosymbiotic bacteria. In this work we describe the T6SS of Rhizobium etli Mim1, a bacteria able to effectively nodulate common beans. Structural genes and those encoding possible effectors have been identified in a 28-gene DNA region of R. etli Mim1 pRetMIM1f plasmid. Immunodetection of Hcp protein, a conserved key structural component of T6SS systems, indicates that this secretion system is active at high cell densities, in the presence of root exudates, and in bean nodules. Rhizobium etli mutants affected in T6SS structural genes produced plants with lower dry weight and smaller nodules than the wild-type strain, indicating for the first time that the T6SS plays a positive role in Rhizobium-legume symbiosis.
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Affiliation(s)
- Alvaro Salinero-Lanzarote
- Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid (UPM)-Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Campus de Montegancedo, 28223 Madrid, Spain.,Departamento de Biotecnología y Biología Vegetal, ETSI Agronómica, Alimentaria y de Biosistemas, Universidad Politécnica de Madrid, 28040 Madrid, Spain
| | - Alba Pacheco-Moreno
- Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid (UPM)-Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Campus de Montegancedo, 28223 Madrid, Spain.,Departamento de Biotecnología y Biología Vegetal, ETSI Agronómica, Alimentaria y de Biosistemas, Universidad Politécnica de Madrid, 28040 Madrid, Spain
| | - Lucía Domingo-Serrano
- Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid (UPM)-Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Campus de Montegancedo, 28223 Madrid, Spain.,Departamento de Biotecnología y Biología Vegetal, ETSI Agronómica, Alimentaria y de Biosistemas, Universidad Politécnica de Madrid, 28040 Madrid, Spain
| | - David Durán
- Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid (UPM)-Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Campus de Montegancedo, 28223 Madrid, Spain.,Departamento de Biotecnología y Biología Vegetal, ETSI Agronómica, Alimentaria y de Biosistemas, Universidad Politécnica de Madrid, 28040 Madrid, Spain
| | | | | | - Marta Albareda
- Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid (UPM)-Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Campus de Montegancedo, 28223 Madrid, Spain.,Departamento de Biotecnología y Biología Vegetal, ETSI Agronómica, Alimentaria y de Biosistemas, Universidad Politécnica de Madrid, 28040 Madrid, Spain
| | - José Manuel Palacios
- Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid (UPM)-Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Campus de Montegancedo, 28223 Madrid, Spain.,Departamento de Biotecnología y Biología Vegetal, ETSI Agronómica, Alimentaria y de Biosistemas, Universidad Politécnica de Madrid, 28040 Madrid, Spain
| | - Luis Rey
- Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid (UPM)-Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Campus de Montegancedo, 28223 Madrid, Spain.,Departamento de Biotecnología y Biología Vegetal, ETSI Agronómica, Alimentaria y de Biosistemas, Universidad Politécnica de Madrid, 28040 Madrid, Spain
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19
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Microbial associations enabling nitrogen acquisition in plants. Curr Opin Microbiol 2019; 49:83-89. [DOI: 10.1016/j.mib.2019.10.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Revised: 10/03/2019] [Accepted: 10/11/2019] [Indexed: 01/29/2023]
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20
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Esmaeel Q, Jacquard C, Clément C, Sanchez L, Ait Barka E. Genome sequencing and traits analysis of Burkholderia strains reveal a promising biocontrol effect against grey mould disease in grapevine (Vitis vinifera L.). World J Microbiol Biotechnol 2019; 35:40. [DOI: 10.1007/s11274-019-2613-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Accepted: 02/01/2019] [Indexed: 12/11/2022]
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21
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Spiewak HL, Shastri S, Zhang L, Schwager S, Eberl L, Vergunst AC, Thomas MS. Burkholderia cenocepacia utilizes a type VI secretion system for bacterial competition. Microbiologyopen 2019; 8:e00774. [PMID: 30628184 PMCID: PMC6612558 DOI: 10.1002/mbo3.774] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Revised: 11/07/2018] [Accepted: 11/07/2018] [Indexed: 01/24/2023] Open
Abstract
Burkholderia cenocepacia is an opportunistic bacterial pathogen that poses a significant threat to individuals with cystic fibrosis by provoking a strong inflammatory response within the lung. It possesses a type VI secretion system (T6SS), a secretory apparatus that can perforate the cellular membrane of other bacterial species and/or eukaryotic targets, to deliver an arsenal of effector proteins. The B. cenocepacia T6SS (T6SS-1) has been shown to be implicated in virulence in rats and contributes toward actin rearrangements and inflammasome activation in B. cenocepacia-infected macrophages. Here, we present bioinformatics evidence to suggest that T6SS-1 is the archetype T6SS in the Burkholderia genus. We show that B. cenocepacia T6SS-1 is active under normal laboratory growth conditions and displays antibacterial activity against other Gram-negative bacterial species. Moreover, B. cenocepacia T6SS-1 is not required for virulence in three eukaryotic infection models. Bioinformatics analysis identified several candidate T6SS-dependent effectors that may play a role in the antibacterial activity of B. cenocepacia T6SS-1. We conclude that B. cenocepacia T6SS-1 plays an important role in bacterial competition for this organism, and probably in all Burkholderia species that possess this system, thereby broadening the range of species that utilize the T6SS for this purpose.
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Affiliation(s)
- Helena L. Spiewak
- Department of Infection, Immunity and Cardiovascular Disease, The Medical SchoolThe University of SheffieldSheffieldUK,Present address:
Northern Genetics Service, The Newcastle upon Tyne Hospitals NHS Foundation Trust, Institute of Genetic MedicineInternational Centre for LifeNewcastle upon TyneUK
| | - Sravanthi Shastri
- Department of Infection, Immunity and Cardiovascular Disease, The Medical SchoolThe University of SheffieldSheffieldUK
| | - Lili Zhang
- VBMI, INSERM, Université de MontpellierNîmesFrance,Present address:
Section of Molecular Biology, Division of Biological SciencesUniversity of California, San DiegoLa JollaCalifornia
| | - Stephan Schwager
- Department of Plant and Microbial BiologyUniversity of ZurichZurichSwitzerland,Present address:
Analytical ChemistrySynthes GmbHOberdorf BLSwitzerland
| | - Leo Eberl
- Department of Plant and Microbial BiologyUniversity of ZurichZurichSwitzerland
| | | | - Mark S. Thomas
- Department of Infection, Immunity and Cardiovascular Disease, The Medical SchoolThe University of SheffieldSheffieldUK
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