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Competitiveness and Phylogenetic Relationship of Rhizobial Strains with Different Symbiotic Efficiency in Trifolium repens: Conversion of Parasitic into Non-Parasitic Rhizobia by Natural Symbiotic Gene Transfer. BIOLOGY 2023; 12:biology12020243. [PMID: 36829520 PMCID: PMC9953144 DOI: 10.3390/biology12020243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Revised: 01/25/2023] [Accepted: 01/27/2023] [Indexed: 02/09/2023]
Abstract
In Uruguayan soils, populations of native and naturalized rhizobia nodulate white clover. These populations include efficient rhizobia but also parasitic strains, which compete for nodule occupancy and hinder optimal nitrogen fixation by the grassland. Nodulation competitiveness assays using gusA-tagged strains proved a high nodule occupancy by the inoculant strain U204, but this was lower than the strains with intermediate efficiencies, U268 and U1116. Clover biomass production only decreased when the parasitic strain UP3 was in a 99:1 ratio with U204, but not when UP3 was at equal or lower numbers than U204. Based on phylogenetic analyses, strains with different efficiencies did not cluster together, and U1116 grouped with the parasitic strains. Our results suggest symbiotic gene transfer from an effective strain to U1116, thereby improving its symbiotic efficiency. Genome sequencing of U268 and U204 strains allowed us to assign them to species Rhizobium redzepovicii, the first report of this species nodulating clover, and Rhizobium leguminosarun, respectively. We also report the presence of hrrP- and sapA-like genes in the genomes of WSM597, U204, and U268 strains, which are related to symbiotic efficiency in rhizobia. Interestingly, we report here chromosomally located hrrP-like genes.
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Colombi E, Hill Y, Lines R, Sullivan JT, Kohlmeier MG, Christophersen CT, Ronson CW, Terpolilli JJ, Ramsay JP. Population genomics of Australian indigenous Mesorhizobium reveals diverse nonsymbiotic genospecies capable of nitrogen-fixing symbioses following horizontal gene transfer. Microb Genom 2023; 9:mgen000918. [PMID: 36748564 PMCID: PMC9973854 DOI: 10.1099/mgen.0.000918] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Mesorhizobia are soil bacteria that establish nitrogen-fixing symbioses with various legumes. Novel symbiotic mesorhizobia frequently evolve following horizontal transfer of symbiosis-gene-carrying integrative and conjugative elements (ICESyms) to indigenous mesorhizobia in soils. Evolved symbionts exhibit a wide range in symbiotic effectiveness, with some fixing nitrogen poorly or not at all. Little is known about the genetic diversity and symbiotic potential of indigenous soil mesorhizobia prior to ICESym acquisition. Here we sequenced genomes of 144 Mesorhizobium spp. strains cultured directly from cultivated and uncultivated Australian soils. Of these, 126 lacked symbiosis genes. The only isolated symbiotic strains were either exotic strains used previously as legume inoculants, or indigenous mesorhizobia that had acquired exotic ICESyms. No native symbiotic strains were identified. Indigenous nonsymbiotic strains formed 22 genospecies with phylogenomic diversity overlapping the diversity of internationally isolated symbiotic Mesorhizobium spp. The genomes of indigenous mesorhizobia exhibited no evidence of prior involvement in nitrogen-fixing symbiosis, yet their core genomes were similar to symbiotic strains and they generally lacked genes for synthesis of biotin, nicotinate and thiamine. Genomes of nonsymbiotic mesorhizobia harboured similar mobile elements to those of symbiotic mesorhizobia, including ICESym-like elements carrying aforementioned vitamin-synthesis genes but lacking symbiosis genes. Diverse indigenous isolates receiving ICESyms through horizontal gene transfer formed effective symbioses with Lotus and Biserrula legumes, indicating most nonsymbiotic mesorhizobia have an innate capacity for nitrogen-fixing symbiosis following ICESym acquisition. Non-fixing ICESym-harbouring strains were isolated sporadically within species alongside effective symbionts, indicating chromosomal lineage does not predict symbiotic potential. Our observations suggest previously observed genomic diversity amongst symbiotic Mesorhizobium spp. represents a fraction of the extant diversity of nonsymbiotic strains. The overlapping phylogeny of symbiotic and nonsymbiotic clades suggests major clades of Mesorhizobium diverged prior to introduction of symbiosis genes and therefore chromosomal genes involved in symbiosis have evolved largely independent of nitrogen-fixing symbiosis.
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Affiliation(s)
- Elena Colombi
- Curtin Medical School, Curtin University, Bentley, Western Australia 6102, Australia.,Curtin Health Innovation Research Institute, Curtin University, Bentley, Western Australia 6102, Australia.,Present address: School of Agriculture and Food, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Victoria 3010, Australia
| | - Yvette Hill
- Legume Rhizobium Sciences, Food Futures Institute, Murdoch University, 90 South St, Murdoch, Western Australia 6150, Australia
| | - Rose Lines
- Trace and Environmental DNA (TrEnD) Laboratory, School of Molecular and Life Sciences, Curtin University, Kent Street, Bentley, Western Australia 6102, Australia
| | - John T Sullivan
- Department of Microbiology and Immunology, University of Otago, Dunedin, New Zealand
| | - MacLean G Kohlmeier
- Legume Rhizobium Sciences, Food Futures Institute, Murdoch University, 90 South St, Murdoch, Western Australia 6150, Australia
| | - Claus T Christophersen
- Trace and Environmental DNA (TrEnD) Laboratory, School of Molecular and Life Sciences, Curtin University, Kent Street, Bentley, Western Australia 6102, Australia.,School of Medical & Health Sciences, Edith Cowan University, Joondalup, Western Australia, Australia.,Centre for Integrative Metabolomics and Computational Biology, Edith Cowan University, Joondalup, Western Australia, Australia
| | - Clive W Ronson
- Department of Microbiology and Immunology, University of Otago, Dunedin, New Zealand
| | - Jason J Terpolilli
- Legume Rhizobium Sciences, Food Futures Institute, Murdoch University, 90 South St, Murdoch, Western Australia 6150, Australia
| | - Joshua P Ramsay
- Curtin Medical School, Curtin University, Bentley, Western Australia 6102, Australia.,Curtin Health Innovation Research Institute, Curtin University, Bentley, Western Australia 6102, Australia
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Provorov NA, Andronov EE, Kimeklis AK, Onishchuk OP, Igolkina AA, Karasev ES. Microevolution, speciation and macroevolution in rhizobia: Genomic mechanisms and selective patterns. FRONTIERS IN PLANT SCIENCE 2022; 13:1026943. [PMID: 36388581 PMCID: PMC9640933 DOI: 10.3389/fpls.2022.1026943] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Accepted: 10/06/2022] [Indexed: 06/16/2023]
Abstract
Nodule bacteria (rhizobia), N2-fixing symbionts of leguminous plants, represent an excellent model to study the fundamental issues of evolutionary biology, including the tradeoff between microevolution, speciation, and macroevolution, which remains poorly understood for free-living organisms. Taxonomically, rhizobia are extremely diverse: they are represented by nearly a dozen families of α-proteobacteria (Rhizobiales) and by some β-proteobacteria. Their genomes are composed of core parts, including house-keeping genes (hkg), and of accessory parts, including symbiotically specialized (sym) genes. In multipartite genomes of evolutionary advanced fast-growing species (Rhizobiaceae), sym genes are clustered on extra-chromosomal replicons (megaplasmids, chromids), facilitating gene transfer in plant-associated microbial communities. In this review, we demonstrate that in rhizobia, microevolution and speciation involve different genomic and ecological mechanisms: the first one is based on the diversification of sym genes occurring under the impacts of host-induced natural selection (including its disruptive, frequency-dependent and group forms); the second one-on the diversification of hkgs under the impacts of unknown factors. By contrast, macroevolution represents the polyphyletic origin of super-species taxa, which are dependent on the transfer of sym genes from rhizobia to various soil-borne bacteria. Since the expression of newly acquired sym genes on foreign genomic backgrounds is usually restricted, conversion of resulted recombinants into the novel rhizobia species involves post-transfer genetic changes. They are presumably supported by host-induced selective processes resulting in the sequential derepression of nod genes responsible for nodulation and of nif/fix genes responsible for symbiotic N2 fixation.
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Affiliation(s)
- Nikolay A. Provorov
- Laboratory of Microbiological Monitoring and Bioremediation of Soils, All-Russian Research Institute for Agricultural Microbiology, Pushkin, Russia
| | - Evgeny E. Andronov
- Laboratory of Microbiological Monitoring and Bioremediation of Soils, All-Russian Research Institute for Agricultural Microbiology, Pushkin, Russia
- Laboratory of Soil Biology and Biochemistry, V.V. Dokuchaev Soil Science Institute, Moscow, Russia
| | - Anastasiia K. Kimeklis
- Laboratory of Microbiological Monitoring and Bioremediation of Soils, All-Russian Research Institute for Agricultural Microbiology, Pushkin, Russia
- Department of Applied Ecology, St. Petersburg State University, Saint-Petersburg, Russia
| | - Olga P. Onishchuk
- Laboratory of Microbiological Monitoring and Bioremediation of Soils, All-Russian Research Institute for Agricultural Microbiology, Pushkin, Russia
| | - Anna A. Igolkina
- Gregor Mendel Institute, Austrian Academy of Sciences, Vienna BioCenter, Vienna, Austria
| | - Evgeny S. Karasev
- Laboratory of Microbiological Monitoring and Bioremediation of Soils, All-Russian Research Institute for Agricultural Microbiology, Pushkin, Russia
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Baymiev AK, Akimova ES, Koryakov IS, Vladimirova AA, Baymiev AK. The Composition of Lotus corniculatus Root Nodule Bacteria Depending on the Host Plant Vegetation Stage. Microbiology (Reading) 2022. [DOI: 10.1134/s0026261722601154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Abstract
Root nodulating rhizobia are nearly ubiquitous in soils and provide the critical service of nitrogen fixation to thousands of legume species, including staple crops. However, the magnitude of fixed nitrogen provided to hosts varies markedly among rhizobia strains, despite host legumes having mechanisms to selectively reward beneficial strains and to punish ones that do not fix sufficient nitrogen. Variation in the services of microbial mutualists is considered paradoxical given host mechanisms to select beneficial genotypes. Moreover, the recurrent evolution of non-fixing symbiont genotypes is predicted to destabilize symbiosis, but breakdown has rarely been observed. Here, we deconstructed hundreds of genome sequences from genotypically and phenotypically diverse Bradyrhizobium strains and revealed mechanisms that generate variation in symbiotic nitrogen fixation. We show that this trait is conferred by a modular system consisting of many extremely large integrative conjugative elements and few conjugative plasmids. Their transmissibility and propensity to reshuffle genes generate new combinations that lead to uncooperative genotypes and make individual partnerships unstable. We also demonstrate that these same properties extend beneficial associations to diverse host species and transfer symbiotic capacity among diverse strains. Hence, symbiotic nitrogen fixation is underpinned by modularity, which engenders flexibility, a feature that reconciles evolutionary robustness and instability. These results provide new insights into mechanisms driving the evolution of mobile genetic elements. Moreover, they yield a new predictive model on the evolution of rhizobial symbioses, one that informs on the health of organisms and ecosystems that are hosts to symbionts and that helps resolve the long-standing paradox.
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Wardell GE, Hynes MF, Young PJ, Harrison E. Why are rhizobial symbiosis genes mobile? Philos Trans R Soc Lond B Biol Sci 2022; 377:20200471. [PMID: 34839705 PMCID: PMC8628070 DOI: 10.1098/rstb.2020.0471] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Accepted: 07/28/2021] [Indexed: 11/12/2022] Open
Abstract
Rhizobia are one of the most important and best studied groups of bacterial symbionts. They are defined by their ability to establish nitrogen-fixing intracellular infections within plant hosts. One surprising feature of this symbiosis is that the bacterial genes required for this complex trait are not fixed within the chromosome, but are encoded on mobile genetic elements (MGEs), namely plasmids or integrative and conjugative elements. Evidence suggests that many of these elements are actively mobilizing within rhizobial populations, suggesting that regular symbiosis gene transfer is part of the ecology of rhizobial symbionts. At first glance, this is counterintuitive. The symbiosis trait is highly complex, multipartite and tightly coevolved with the legume hosts, while transfer of genes can be costly and disrupt coadaptation between the chromosome and the symbiosis genes. However, horizontal gene transfer is a process driven not only by the interests of the host bacterium, but also, and perhaps predominantly, by the interests of the MGEs that facilitate it. Thus understanding the role of horizontal gene transfer in the rhizobium-legume symbiosis requires a 'mobile genetic element's-eye view' on the ecology and evolution of this important symbiosis. This article is part of the theme issue 'The secret lives of microbial mobile genetic elements'.
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Affiliation(s)
- Grace E. Wardell
- Department of Animal Plant Sciences, University of Sheffield, Western Bank, Sheffield S10 1EA, UK
| | - Michael F. Hynes
- Biological Sciences, University of Calgary, 2500 University Drive NW, Calgary, Alberta, Canada T2N 1N4
| | - Peter J. Young
- Department of Biology, University of York, Wentworth Way, York YO10 5DD, UK
| | - Ellie Harrison
- Department of Animal Plant Sciences, University of Sheffield, Western Bank, Sheffield S10 1EA, UK
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7
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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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8
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Evolution of diverse effective N 2-fixing microsymbionts of Cicer arietinum following horizontal transfer of the Mesorhizobium ciceri CC1192 symbiosis integrative and conjugative element. Appl Environ Microbiol 2021; 87:AEM.02558-20. [PMID: 33355157 PMCID: PMC8090884 DOI: 10.1128/aem.02558-20] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Rhizobia are soil bacteria capable of forming N2-fixing symbioses with legumes, with highly effective strains often selected in agriculture as inoculants to maximize symbiotic N2 fixation. When rhizobia in the genus Mesorhizobium have been introduced with exotic legumes into farming systems, horizontal transfer of symbiosis Integrative and Conjugative Elements (ICEs) from the inoculant strain to soil bacteria has resulted in the evolution of ineffective N2-fixing rhizobia that are competitive for nodulation with the target legume. In Australia, Cicer arietinum (chickpea) has been inoculated since the 1970's with Mesorhizobium ciceri sv. ciceri CC1192, a highly effective strain from Israel. Although the full genome sequence of this organism is available, little is known about the mobility of its symbiosis genes and the diversity of cultivated C. arietinum-nodulating organisms. Here, we show the CC1192 genome harbors a 419-kb symbiosis ICE (ICEMcSym1192) and a 648-kb repABC-type plasmid pMC1192 carrying putative fix genes. We sequenced the genomes of 11 C. arietinum nodule isolates from a field site exclusively inoculated with CC1192 and showed they were diverse unrelated Mesorhizobium carrying ICEMcSym1192, indicating they had acquired the ICE by environmental transfer. No exconjugants harboured pMc1192 and the plasmid was not essential for N2 fixation in CC1192. Laboratory conjugation experiments confirmed ICEMcSym1192 is mobile, integrating site-specifically within the 3' end of one of the four ser-tRNA genes in the R7ANS recipient genome. Strikingly, all ICEMcSym1192 exconjugants were as efficient at fixing N2 with C. arietinum as CC1192, demonstrating ICE transfer does not necessarily yield ineffective microsymbionts as previously observed.Importance Symbiotic N2 fixation is a key component of sustainable agriculture and in many parts of the world legumes are inoculated with highly efficient strains of rhizobia to maximise fixed N2 inputs into farming systems. Symbiosis genes for Mesorhizobium spp. are often encoded chromosomally within mobile gene clusters called Integrative and Conjugative Elements or ICEs. In Australia, where all agricultural legumes and their rhizobia are exotic, horizontal transfer of ICEs from inoculant Mesorhizobium strains to native rhizobia has led to the evolution of inefficient strains that outcompete the original inoculant, with the potential to render it ineffective. However, the commercial inoculant strain for Cicer arietinum (chickpea), M. ciceri CC1192, has a mobile symbiosis ICE (ICEMcSym1192) which can support high rates of N2 fixation following either environmental or laboratory transfer into diverse Mesorhizobium backgrounds, demonstrating ICE transfer does not necessarily yield ineffective microsymbionts as previously observed.
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9
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Gluck-Thaler E, Cerutti A, Perez-Quintero AL, Butchacas J, Roman-Reyna V, Madhavan VN, Shantharaj D, Merfa MV, Pesce C, Jauneau A, Vancheva T, Lang JM, Allen C, Verdier V, Gagnevin L, Szurek B, Beckham GT, De La Fuente L, Patel HK, Sonti RV, Bragard C, Leach JE, Noël LD, Slot JC, Koebnik R, Jacobs JM. Repeated gain and loss of a single gene modulates the evolution of vascular plant pathogen lifestyles. SCIENCE ADVANCES 2020; 6:6/46/eabc4516. [PMID: 33188025 PMCID: PMC7673761 DOI: 10.1126/sciadv.abc4516] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Accepted: 09/30/2020] [Indexed: 05/21/2023]
Abstract
Vascular plant pathogens travel long distances through host veins, leading to life-threatening, systemic infections. In contrast, nonvascular pathogens remain restricted to infection sites, triggering localized symptom development. The contrasting features of vascular and nonvascular diseases suggest distinct etiologies, but the basis for each remains unclear. Here, we show that the hydrolase CbsA acts as a phenotypic switch between vascular and nonvascular plant pathogenesis. cbsA was enriched in genomes of vascular phytopathogenic bacteria in the family Xanthomonadaceae and absent in most nonvascular species. CbsA expression allowed nonvascular Xanthomonas to cause vascular blight, while cbsA mutagenesis resulted in reduction of vascular or enhanced nonvascular symptom development. Phylogenetic hypothesis testing further revealed that cbsA was lost in multiple nonvascular lineages and more recently gained by some vascular subgroups, suggesting that vascular pathogenesis is ancestral. Our results overall demonstrate how the gain and loss of single loci can facilitate the evolution of complex ecological traits.
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Affiliation(s)
- Emile Gluck-Thaler
- Department of Plant Pathology, The Ohio State University, Columbus, OH 43210, USA
- Department of Biology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Aude Cerutti
- LIPM, Université de Toulouse, INRAE, CNRS, Université Paul Sabatier, Castanet-Tolosan, France
| | | | - Jules Butchacas
- Department of Plant Pathology, The Ohio State University, Columbus, OH 43210, USA
- Infectious Disease Institute, The Ohio State University, Columbus, OH 43210, USA
| | - Verónica Roman-Reyna
- Department of Plant Pathology, The Ohio State University, Columbus, OH 43210, USA
- Infectious Disease Institute, The Ohio State University, Columbus, OH 43210, USA
| | | | - Deepak Shantharaj
- Department of Entomology and Plant Pathology, Auburn University, Auburn, AL 36849, USA
| | - Marcus V Merfa
- Department of Entomology and Plant Pathology, Auburn University, Auburn, AL 36849, USA
| | - Céline Pesce
- IRD, CIRAD, Université Montpellier, IPME, Montpellier, France
- Earth & Life Institute, Université Catholique de Louvain, Louvain-la-Neuve, Belgium
- HM Clause (Limagrain group), Davis, CA, 95618, USA
| | - Alain Jauneau
- Institut Fédératif de Recherche 3450, Plateforme Imagerie, Pôle de Biotechnologie Végétale, Castanet-Tolosan, France
| | - Taca Vancheva
- IRD, CIRAD, Université Montpellier, IPME, Montpellier, France
- Earth & Life Institute, Université Catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Jillian M Lang
- Agricultural Biology, Colorado State University, Fort Collins, CO, USA
| | - Caitilyn Allen
- Department of Plant Pathology, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Valerie Verdier
- IRD, CIRAD, Université Montpellier, IPME, Montpellier, France
| | - Lionel Gagnevin
- IRD, CIRAD, Université Montpellier, IPME, Montpellier, France
| | - Boris Szurek
- IRD, CIRAD, Université Montpellier, IPME, Montpellier, France
| | - Gregg T Beckham
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, CO 80401, USA
| | - Leonardo De La Fuente
- Department of Entomology and Plant Pathology, Auburn University, Auburn, AL 36849, USA
| | | | - Ramesh V Sonti
- CSIR-Centre for Cellular and Molecular Biology, Hyderabad 500007, India
| | - Claude Bragard
- Earth & Life Institute, Université Catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Jan E Leach
- Agricultural Biology, Colorado State University, Fort Collins, CO, USA
| | - Laurent D Noël
- LIPM, Université de Toulouse, INRAE, CNRS, Université Paul Sabatier, Castanet-Tolosan, France
| | - Jason C Slot
- Department of Plant Pathology, The Ohio State University, Columbus, OH 43210, USA
- Infectious Disease Institute, The Ohio State University, Columbus, OH 43210, USA
| | - Ralf Koebnik
- IRD, CIRAD, Université Montpellier, IPME, Montpellier, France.
| | - Jonathan M Jacobs
- Department of Plant Pathology, The Ohio State University, Columbus, OH 43210, USA.
- Infectious Disease Institute, The Ohio State University, Columbus, OH 43210, USA
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Cavassim MIA, Moeskjær S, Moslemi C, Fields B, Bachmann A, Vilhjálmsson BJ, Schierup MH, W. Young JP, Andersen SU. Symbiosis genes show a unique pattern of introgression and selection within a Rhizobium leguminosarum species complex. Microb Genom 2020; 6:e000351. [PMID: 32176601 PMCID: PMC7276703 DOI: 10.1099/mgen.0.000351] [Citation(s) in RCA: 24] [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: 11/29/2019] [Accepted: 02/17/2020] [Indexed: 12/22/2022] Open
Abstract
Rhizobia supply legumes with fixed nitrogen using a set of symbiosis genes. These can cross rhizobium species boundaries, but it is unclear how many other genes show similar mobility. Here, we investigate inter-species introgression using de novo assembly of 196 Rhizobium leguminosarum sv. trifolii genomes. The 196 strains constituted a five-species complex, and we calculated introgression scores based on gene-tree traversal to identify 171 genes that frequently cross species boundaries. Rather than relying on the gene order of a single reference strain, we clustered the introgressing genes into four blocks based on population structure-corrected linkage disequilibrium patterns. The two largest blocks comprised 125 genes and included the symbiosis genes, a smaller block contained 43 mainly chromosomal genes, and the last block consisted of three genes with variable genomic location. All introgression events were likely mediated by conjugation, but only the genes in the symbiosis linkage blocks displayed overrepresentation of distinct, high-frequency haplotypes. The three genes in the last block were core genes essential for symbiosis that had, in some cases, been mobilized on symbiosis plasmids. Inter-species introgression is thus not limited to symbiosis genes and plasmids, but other cases are infrequent and show distinct selection signatures.
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Affiliation(s)
- Maria Izabel A. Cavassim
- Bioinformatics Research Centre, Aarhus University, Aarhus, Denmark
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
| | - Sara Moeskjær
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
| | - Camous Moslemi
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
| | | | - Asger Bachmann
- Bioinformatics Research Centre, Aarhus University, Aarhus, Denmark
| | | | | | | | - Stig U. Andersen
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
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11
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Provorov NA, Andronov EE, Kimeklis AK, Chirak ER, Karasev ES, Aksenova TS, Kopat VV. Evolutionary Geography of Root Nodule Bacteria: Speciation Directed by the Host Plants. Microbiology (Reading) 2020. [DOI: 10.1134/s0026261720010129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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12
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Daubech B, Poinsot V, Klonowska A, Capela D, Chaintreuil C, Moulin L, Marchetti M, Masson-Boivin C. noeM, a New Nodulation Gene Involved in the Biosynthesis of Nod Factors with an Open-Chain Oxidized Terminal Residue and in the Symbiosis with Mimosa pudica. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2019; 32:1635-1648. [PMID: 31617792 DOI: 10.1094/mpmi-06-19-0168-r] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The β-rhizobium Cupriavidus taiwanensis is a nitrogen-fixing symbiont of Mimosa pudica. Nod factors produced by this species were previously found to be pentameric chitin-oligomers carrying common C18:1 or C16:0 fatty acyl chains, N-methylated and C-6 carbamoylated on the nonreducing terminal N-acetylglucosamine and sulfated on the reducing terminal residue. Here, we report that, in addition, C. taiwanensis LMG19424 produces molecules where the reducing sugar is open and oxidized. We identified a novel nodulation gene located on the symbiotic plasmid pRalta, called noeM, which is involved in this atypical Nod factor structure. noeM encodes a transmembrane protein bearing a fatty acid hydroxylase domain. This gene is expressed during symbiosis with M. pudica and requires NodD and luteolin for optimal expression. The closest noeM homologs formed a separate phylogenetic clade containing rhizobial genes only, which are located on symbiosis plasmids downstream from a nod box. Corresponding proteins, referred to as NoeM, may have specialized in symbiosis via the connection to the nodulation pathway and the spread in rhizobia. noeM was mostly found in isolates of the Mimoseae tribe, and specifically detected in all tested strains able to nodulate M. pudica. A noeM deletion mutant of C. taiwanensis was affected for the nodulation of M. pudica, confirming the role of noeM in the symbiosis with this legume.
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Affiliation(s)
- Benoit Daubech
- LIPM, Université de Toulouse, INRA, CNRS, Castanet-Tolosan, France
| | - Verena Poinsot
- Université de Toulouse 3, UPS CNRS 5623, UMR, Lab IMRCP, F-31062 Toulouse, France
| | | | - Delphine Capela
- LIPM, Université de Toulouse, INRA, CNRS, Castanet-Tolosan, France
| | - Clémence Chaintreuil
- Université Montpellier, CIRAD, INRA, IRD, Montpellier SupAgro, LSTM, Montpellier, France
| | - Lionel Moulin
- IRD, CIRAD, Université Montpellier, IPME, Montpellier, France
| | - Marta Marchetti
- LIPM, Université de Toulouse, INRA, CNRS, Castanet-Tolosan, France
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13
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Bamba M, Aoki S, Kajita T, Setoguchi H, Watano Y, Sato S, Tsuchimatsu T. Exploring Genetic Diversity and Signatures of Horizontal Gene Transfer in Nodule Bacteria Associated with Lotus japonicus in Natural Environments. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2019; 32:1110-1120. [PMID: 30880586 DOI: 10.1094/mpmi-02-19-0039-r] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
To investigate the genetic diversity and understand the process of horizontal gene transfer (HGT) in nodule bacteria associated with Lotus japonicus, we analyzed sequences of three housekeeping and five symbiotic genes using samples from a geographically wide range in Japan. A phylogenetic analysis of the housekeeping genes indicated that L. japonicus in natural environments was associated with diverse lineages of Mesorhizobium spp., whereas the sequences of symbiotic genes were highly similar between strains, resulting in remarkably low nucleotide diversity at both synonymous and nonsynonymous sites. Guanine-cytosine content values were lower in symbiotic genes, and relative frequencies of recombination between symbiotic genes were also lower than those between housekeeping genes. An analysis of molecular variance showed significant genetic differentiation among populations in both symbiotic and housekeeping genes. These results confirm that the Mesorhizobium genes required for symbiosis with L. japonicus behave as a genomic island (i.e., a symbiosis island) and suggest that this island has spread into diverse genomic backgrounds of Mesorhizobium via HGT events in natural environments. Furthermore, our data compilation revealed that the genetic diversity of symbiotic genes in L. japonicus-associated symbionts was among the lowest compared with reports of other species, which may be related to the recent population expansion proposed in Japanese populations of L. japonicus.
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Affiliation(s)
- Masaru Bamba
- Department of Biology (Frontier Science Program), Graduate School of Science and Engineering, Chiba University, 1-33 Yayoi, Inage, Chiba 263-8522, Japan
| | - Seishiro Aoki
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan
| | - Tadashi Kajita
- Iriomote Station, Tropical Biosphere Research Center, the University of Ryukyus, 870 Uehara, Taketomi-cho, Yaeyama-gun, Okinawa 907-1541, Japan
| | - Hiroaki Setoguchi
- Graduate School of Human and Environmental Studies, Kyoto University, Yoshidanihonmatsu-cho, Sakyo-ku, Kyoto 606-8501 Japan
| | - Yasuyuki Watano
- Department of Biology, Graduate School of Science, Chiba University
| | - Shusei Sato
- Graduate School of Life Sciences, Tohoku University, 2-1-1 Katahira, Aoba, Sendai 980-8577, Japan
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14
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Burghardt LT, Epstein B, Tiffin P. Legacy of prior host and soil selection on rhizobial fitness in planta. Evolution 2019; 73:2013-2023. [PMID: 31334838 DOI: 10.1111/evo.13807] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2019] [Revised: 06/19/2019] [Accepted: 06/20/2019] [Indexed: 01/03/2023]
Abstract
Measuring selection acting on microbial populations in natural or even seminatural environments is challenging because many microbial populations experience variable selection. The majority of rhizobial bacteria are found in the soil. However, they also live symbiotically inside nodules of legume hosts and each nodule can release thousands of daughter cells back into the soil. We tested how past selection (i.e., legacies) by two plant genotypes and by the soil alone affected selection and genetic diversity within a population of 101 strains of Ensifer meliloti. We also identified allelic variants most strongly associated with soil- and host-dependent fitness. In addition to imposing direct selection on rhizobia populations, soil and host environments had lasting effects across host generations. Host presence and genotype during the legacy period explained 22% and 12% of the variance in the strain composition of nodule communities in the second cohort, respectively. Although strains with high host fitness in the legacy cohort tended to be enriched in the second cohort, the diversity of the strain community was greater when the second cohort was preceded by host rather than soil legacies. Our results indicate the potential importance of soil selection driving the evolution of these plant-associated microbes.
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Affiliation(s)
- Liana T Burghardt
- Department of Plant and Microbial Biology, University of Minnesota, St. Paul, Minnesota, 55108
| | - Brendan Epstein
- Department of Plant and Microbial Biology, University of Minnesota, St. Paul, Minnesota, 55108
| | - Peter Tiffin
- Department of Plant and Microbial Biology, University of Minnesota, St. Paul, Minnesota, 55108
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15
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Liu Z, Chen W, Jiao S, Wang X, Fan M, Wang E, Wei G. New Insight into the Evolution of Symbiotic Genes in Black Locust-Associated Rhizobia. Genome Biol Evol 2019; 11:1736-1750. [PMID: 31192354 PMCID: PMC6698633 DOI: 10.1093/gbe/evz116] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/09/2019] [Indexed: 11/29/2022] Open
Abstract
Nitrogen fixation in legumes occurs via symbiosis with rhizobia. This process involves packages of symbiotic genes on mobile genetic elements that are readily transferred within or between rhizobial species, furnishing the recipient with the ability to interact with plant hosts. However, it remains elusive whether plant host migration has played a role in shaping the current distribution of genetic variation in symbiotic genes. Herein, we examined the genetic structure and phylogeographic pattern of symbiotic genes in 286 symbiotic strains of Mesorhizobium nodulating black locust (Robinia pseudoacacia), a cross-continental invasive legume species that is native to North America. We conducted detailed phylogeographic analysis and approximate Bayesian computation to unravel the complex demographic history of five key symbiotic genes. The sequencing results indicate an origin of symbiotic genes in Germany rather than North America. Our findings provide strong evidence of prehistoric lineage splitting and spatial expansion events resulting in multiple radiations of descendent clones from founding sequence types worldwide. Estimates of the timescale of divergence in North American and Chinese subclades suggest that black locust-specific symbiotic genes have been present in these continent many thousands of years before recent migration of plant host. Although numerous crop plants, including legumes, have found their centers of origin as centers of evolution and diversity, the number of legume-specific symbiotic genes with a known geographic origin is limited. This work sheds light on the coevolution of legumes and rhizobia.
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Affiliation(s)
- Zhenshan Liu
- State Key Laboratory of Crop Stress Biology in Arid Areas, Shaanxi Key Laboratory of Agricultural and Environmental Microbiology, College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, China
| | - Weimin Chen
- State Key Laboratory of Crop Stress Biology in Arid Areas, Shaanxi Key Laboratory of Agricultural and Environmental Microbiology, College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, China
| | - Shuo Jiao
- State Key Laboratory of Crop Stress Biology in Arid Areas, Shaanxi Key Laboratory of Agricultural and Environmental Microbiology, College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, China
| | - Xinye Wang
- State Key Laboratory of Crop Stress Biology in Arid Areas, Shaanxi Key Laboratory of Agricultural and Environmental Microbiology, College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, China
| | - Miaochun Fan
- State Key Laboratory of Crop Stress Biology in Arid Areas, Shaanxi Key Laboratory of Agricultural and Environmental Microbiology, College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, China
| | - Entao Wang
- Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, México, D.F., Mexico
| | - Gehong Wei
- State Key Laboratory of Crop Stress Biology in Arid Areas, Shaanxi Key Laboratory of Agricultural and Environmental Microbiology, College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, China
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16
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Camacho M, Medina C, Rodríguez-Navarro DN, Temprano Vera F. Biodiversity of rhizobia present in plant nodules of Biserrula pelecinus across Southwest Spain. Syst Appl Microbiol 2019; 42:415-421. [PMID: 30952451 DOI: 10.1016/j.syapm.2019.03.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 03/14/2019] [Accepted: 03/18/2019] [Indexed: 11/29/2022]
Abstract
Biodiversity studies of native Mesorhizobium spp. strains able to nodulate the annual herbaceous legume Biserrula pelecinus L. in soils from Southwest Spain have been carried out. One or two isolates per plant, 30 in total, were randomly selected for further characterization. There was no association between the presence of mesorhizobia nodulating-B. pelecinus and the chemical or textural properties of the soils. The isolates were tested for their symbiotic effectiveness on this forage legume under greenhouse conditions and characterized on the basis of physiological parameters: carbon source utilisation (API 50CH), 16S rRNA sequencing and ERIC-PCR, lipopolysaccharide, protein and plasmid profiles. Our results show that in spite of the great diversity found among the native isolates, most of them belong to the genus Mesorhizobium, the exception being strain B24 which sequence matches 97.52% with Neorhizobium huautlense; this is the first description of a Neorhizobium strain effectively nodulating-biserrula plants. Results of a field trial indicated that some of these isolates could be recommended as inoculants for this legume. B24=DSM 28743=CECT 8815; ENA (HF955513) 16S rRNA sequences of isolates B13, B18, B26, B30 and B1 are deposited at ENA under numbers LS999402 to LS999406, respectively.
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Affiliation(s)
- María Camacho
- IFAPA Centro Las Torres Tomejil, Ctra Sevilla-Cazalla Km 12, 2. 41200 Seville, Spain.
| | - Carlos Medina
- Department of Microbiology, Faculty of Biology, University of Seville, Avda. Reina Mercedes 6, 41012 Seville, Spain
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17
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Corel E, Méheust R, Watson AK, McInerney JO, Lopez P, Bapteste E. Bipartite Network Analysis of Gene Sharings in the Microbial World. Mol Biol Evol 2019; 35:899-913. [PMID: 29346651 PMCID: PMC5888944 DOI: 10.1093/molbev/msy001] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Extensive microbial gene flows affect how we understand virology, microbiology, medical sciences, genetic modification, and evolutionary biology. Phylogenies only provide a narrow view of these gene flows: plasmids and viruses, lacking core genes, cannot be attached to cellular life on phylogenetic trees. Yet viruses and plasmids have a major impact on cellular evolution, affecting both the gene content and the dynamics of microbial communities. Using bipartite graphs that connect up to 149,000 clusters of homologous genes with 8,217 related and unrelated genomes, we can in particular show patterns of gene sharing that do not map neatly with the organismal phylogeny. Homologous genes are recycled by lateral gene transfer, and multiple copies of homologous genes are carried by otherwise completely unrelated (and possibly nested) genomes, that is, viruses, plasmids and prokaryotes. When a homologous gene is present on at least one plasmid or virus and at least one chromosome, a process of "gene externalization," affected by a postprocessed selected functional bias, takes place, especially in Bacteria. Bipartite graphs give us a view of vertical and horizontal gene flow beyond classic taxonomy on a single very large, analytically tractable, graph that goes beyond the cellular Web of Life.
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Affiliation(s)
- Eduardo Corel
- Unité Mixte de Recherche 7138 Evolution Paris-Seine, Centre National de la Recherche Scientifique, Institut de Biologie Paris-Seine, Sorbonne Université, Université Pierre et Marie Curie, Paris, France
| | - Raphaël Méheust
- Unité Mixte de Recherche 7138 Evolution Paris-Seine, Centre National de la Recherche Scientifique, Institut de Biologie Paris-Seine, Sorbonne Université, Université Pierre et Marie Curie, Paris, France
| | - Andrew K Watson
- Unité Mixte de Recherche 7138 Evolution Paris-Seine, Centre National de la Recherche Scientifique, Institut de Biologie Paris-Seine, Sorbonne Université, Université Pierre et Marie Curie, Paris, France
| | - James O McInerney
- Chair in Evolutionary Biology, The University of Manchester, United Kingdom
| | - Philippe Lopez
- Unité Mixte de Recherche 7138 Evolution Paris-Seine, Centre National de la Recherche Scientifique, Institut de Biologie Paris-Seine, Sorbonne Université, Université Pierre et Marie Curie, Paris, France
| | - Eric Bapteste
- Unité Mixte de Recherche 7138 Evolution Paris-Seine, Centre National de la Recherche Scientifique, Institut de Biologie Paris-Seine, Sorbonne Université, Université Pierre et Marie Curie, Paris, France
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18
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traG Gene Is Conserved across Mesorhizobium spp. Able to Nodulate the Same Host Plant and Expressed in Response to Root Exudates. BIOMED RESEARCH INTERNATIONAL 2019; 2019:3715271. [PMID: 30834262 PMCID: PMC6374801 DOI: 10.1155/2019/3715271] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Accepted: 01/09/2019] [Indexed: 11/22/2022]
Abstract
Evidences for an involvement of the bacterial type IV secretion system (T4SS) in the symbiotic relationship between rhizobia and legumes have been pointed out by several recent studies. However, information regarding this secretion system in Mesorhizobium is still very scarce. The aim of the present study was to investigate the phylogeny and expression of the traG gene, which encodes a substrate receptor of the T4SS. In addition, the occurrence and genomic context of this and other T4SS genes, namely, genes from tra/trb and virB/virD4 complexes, were also analyzed in order to unveil the structural and functional organization of T4SS in mesorhizobia. The location of the T4SS genes in the symbiotic region of the analyzed rhizobial genomes, along with the traG phylogeny, suggests that T4SS genes could be horizontally transferred together with the symbiosis genes. Regarding the T4SS structural organization in Mesorhizobium, the virB/virD4 genes were absent in all chickpea (Cicer arietinum L.) microsymbionts and in the Lotus symbiont Mesorhizobium japonicum MAFF303099T. Interestingly, the presence of genes belonging to another secretion system (T3SS) was restricted to these strains lacking the virB/virD4 genes. The traG gene expression was detected in M. mediterraneum Ca36T and M. ciceri LMS-1 strains when exposed to chickpea root exudates and also in the early nodules formed by M. mediterraneum Ca36T, but not in older nodules. This study contributes to a better understanding of the importance of T4SS in mutualistic symbiotic bacteria.
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19
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Porter SS, Faber-Hammond J, Montoya AP, Friesen ML, Sackos C. Dynamic genomic architecture of mutualistic cooperation in a wild population of Mesorhizobium. ISME JOURNAL 2018; 13:301-315. [PMID: 30218020 PMCID: PMC6331556 DOI: 10.1038/s41396-018-0266-y] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Revised: 07/01/2018] [Accepted: 08/04/2018] [Indexed: 12/14/2022]
Abstract
Research on mutualism seeks to explain how cooperation can be maintained when uncooperative mutants co-occur with cooperative kin. Gains and losses of the gene modules required for cooperation punctuate symbiont phylogenies and drive lifestyle transitions between cooperative symbionts and uncooperative free-living lineages over evolutionary time. Yet whether uncooperative symbionts commonly evolve from within cooperative symbiont populations or from within distantly related lineages with antagonistic or free-living lifestyles (i.e., third-party mutualism exploiters or parasites), remains controversial. We use genomic data to show that genotypes that differ in the presence or absence of large islands of symbiosis genes are common within a single wild recombining population of Mesorhizobium symbionts isolated from host tissues and are an important source of standing heritable variation in cooperation in this population. In a focal population of Mesorhizobium, uncooperative variants that lack a symbiosis island segregate at 16% frequency in nodules, and genome size and symbiosis gene number are positively correlated with cooperation. This finding contrasts with the genomic architecture of variation in cooperation in other symbiont populations isolated from host tissues in which the islands of genes underlying cooperation are ubiquitous and variation in cooperation is primarily driven by allelic substitution and individual gene gain and loss events. Our study demonstrates that uncooperative mutants within mutualist populations can comprise a significant component of genetic variation in nature, providing biological rationale for models and experiments that seek to explain the maintenance of mutualism in the face of non-cooperators.
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Affiliation(s)
- Stephanie S Porter
- School of Biological Sciences, Washington State University, Vancouver, WA, 98686, USA.
| | - Joshua Faber-Hammond
- School of Biological Sciences, Washington State University, Vancouver, WA, 98686, USA
| | - Angeliqua P Montoya
- School of Biological Sciences, Washington State University, Vancouver, WA, 98686, USA
| | - Maren L Friesen
- Department of Plant Biology, Michigan State University, East Lansing, MI, 48824, USA.,Department of Plant Pathology, Washington State University, Pullman, WA, 99164, USA.,Department of Crop and Soil Sciences, Washington State University, Pullman, WA, 99164, USA
| | - Cynthia Sackos
- School of Biological Sciences, Washington State University, Vancouver, WA, 98686, USA
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20
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Masson-Boivin C, Sachs JL. Symbiotic nitrogen fixation by rhizobia-the roots of a success story. CURRENT OPINION IN PLANT BIOLOGY 2018; 44:7-15. [PMID: 29289792 DOI: 10.1016/j.pbi.2017.12.001] [Citation(s) in RCA: 102] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Revised: 12/12/2017] [Accepted: 12/13/2017] [Indexed: 05/12/2023]
Abstract
By evolving the dual capacity of intracellular survival and symbiotic nitrogen fixation in legumes, rhizobia have achieved an ecological and evolutionary success that has reshaped our biosphere. Despite complex challenges, including a dual lifestyle of intracellular infection separated by a free-living phase in soil, rhizobial symbiosis has spread horizontally to hundreds of bacterial species and geographically throughout the globe. This symbiosis has also persisted and been reshaped through millions of years of history. Here, we summarize recent advances in our understanding of the molecular mechanisms, ecological settings, and evolutionary pathways that are collectively responsible for this symbiotic success story. We offer predictions of how this symbiosis can evolve under new influences and for the benefit of a burgeoning human population.
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Affiliation(s)
| | - Joel L Sachs
- Department of Evolution Ecology and Organismal Biology, University of California, Riverside, CA, USA
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21
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Andrews M, De Meyer S, James EK, Stępkowski T, Hodge S, Simon MF, Young JPW. Horizontal Transfer of Symbiosis Genes within and Between Rhizobial Genera: Occurrence and Importance. Genes (Basel) 2018; 9:E321. [PMID: 29954096 PMCID: PMC6071183 DOI: 10.3390/genes9070321] [Citation(s) in RCA: 67] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2018] [Revised: 06/21/2018] [Accepted: 06/21/2018] [Indexed: 01/17/2023] Open
Abstract
Rhizobial symbiosis genes are often carried on symbiotic islands or plasmids that can be transferred (horizontal transfer) between different bacterial species. Symbiosis genes involved in horizontal transfer have different phylogenies with respect to the core genome of their ‘host’. Here, the literature on legume⁻rhizobium symbioses in field soils was reviewed, and cases of phylogenetic incongruence between rhizobium core and symbiosis genes were collated. The occurrence and importance of horizontal transfer of rhizobial symbiosis genes within and between bacterial genera were assessed. Horizontal transfer of symbiosis genes between rhizobial strains is of common occurrence, is widespread geographically, is not restricted to specific rhizobial genera, and occurs within and between rhizobial genera. The transfer of symbiosis genes to bacteria adapted to local soil conditions can allow these bacteria to become rhizobial symbionts of previously incompatible legumes growing in these soils. This, in turn, will have consequences for the growth, life history, and biogeography of the legume species involved, which provides a critical ecological link connecting the horizontal transfer of symbiosis genes between rhizobial bacteria in the soil to the above-ground floral biodiversity and vegetation community structure.
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Affiliation(s)
- Mitchell Andrews
- Faculty of Agriculture and Life Sciences, Lincoln University, P.O. Box 84, Lincoln 7647, New Zealand.
| | - Sofie De Meyer
- Centre for Rhizobium Studies, Murdoch University, Murdoch 6150, Australia.
- Laboratory of Microbiology, Department of Biochemistry and Microbiology, Ghent University, 9000 Ghent, Belgium.
| | - Euan K James
- James Hutton Institute, Invergowrie, Dundee DD2 5DA, UK.
| | - Tomasz Stępkowski
- Autonomous Department of Microbial Biology, Faculty of Agriculture and Biology, Warsaw University of Life Sciences (SGGW), 02-776 Warsaw, Poland.
| | - Simon Hodge
- Faculty of Agriculture and Life Sciences, Lincoln University, P.O. Box 84, Lincoln 7647, New Zealand.
| | - Marcelo F Simon
- Embrapa Genetic Resources and Biotechnology, Brasilia DF 70770-917, Brazil.
| | - J Peter W Young
- Department of Biology, University of York, York YO10 5DD, UK.
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22
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Parallels between experimental and natural evolution of legume symbionts. Nat Commun 2018; 9:2264. [PMID: 29891837 PMCID: PMC5995829 DOI: 10.1038/s41467-018-04778-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Accepted: 05/11/2018] [Indexed: 12/29/2022] Open
Abstract
The emergence of symbiotic interactions has been studied using population genomics in nature and experimental evolution in the laboratory, but the parallels between these processes remain unknown. Here we compare the emergence of rhizobia after the horizontal transfer of a symbiotic plasmid in natural populations of Cupriavidus taiwanensis, over 10 MY ago, with the experimental evolution of symbiotic Ralstonia solanacearum for a few hundred generations. In spite of major differences in terms of time span, environment, genetic background, and phenotypic achievement, both processes resulted in rapid genetic diversification dominated by purifying selection. We observe no adaptation in the plasmid carrying the genes responsible for the ecological transition. Instead, adaptation was associated with positive selection in a set of genes that led to the co-option of the same quorum-sensing system in both processes. Our results provide evidence for similarities in experimental and natural evolutionary transitions and highlight the potential of comparisons between both processes to understand symbiogenesis. It is unclear if experimental evolution is a good model for natural processes. Here, Clerissi et al. find parallels between the evolution of symbiosis in rhizobia after horizontal transfer of a plasmid over 10 million years ago and experimentally evolved symbionts.
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23
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Daubech B, Remigi P, Doin de Moura G, Marchetti M, Pouzet C, Auriac MC, Gokhale CS, Masson-Boivin C, Capela D. Spatio-temporal control of mutualism in legumes helps spread symbiotic nitrogen fixation. eLife 2017; 6:e28683. [PMID: 29022875 PMCID: PMC5687860 DOI: 10.7554/elife.28683] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Accepted: 10/11/2017] [Indexed: 01/01/2023] Open
Abstract
Mutualism is of fundamental importance in ecosystems. Which factors help to keep the relationship mutually beneficial and evolutionarily successful is a central question. We addressed this issue for one of the most significant mutualistic interactions on Earth, which associates plants of the leguminosae family and hundreds of nitrogen (N2)-fixing bacterial species. Here we analyze the spatio-temporal dynamics of fixers and non-fixers along the symbiotic process in the Cupriavidus taiwanensis-Mimosa pudica system. N2-fixing symbionts progressively outcompete isogenic non-fixers within root nodules, where N2-fixation occurs, even when they share the same nodule. Numerical simulations, supported by experimental validation, predict that rare fixers will invade a population dominated by non-fixing bacteria during serial nodulation cycles with a probability that is function of initial inoculum, plant population size and nodulation cycle length. Our findings provide insights into the selective forces and ecological factors that may have driven the spread of the N2-fixation mutualistic trait.
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Affiliation(s)
- Benoit Daubech
- The Laboratory of Plant-Microbe InteractionsUniversité de Toulouse, INRA, CNRSCastanet-TolosanFrance
| | - Philippe Remigi
- New Zealand Institute for Advanced StudyMassey UniversityAucklandNew Zealand
| | - Ginaini Doin de Moura
- The Laboratory of Plant-Microbe InteractionsUniversité de Toulouse, INRA, CNRSCastanet-TolosanFrance
| | - Marta Marchetti
- The Laboratory of Plant-Microbe InteractionsUniversité de Toulouse, INRA, CNRSCastanet-TolosanFrance
| | - Cécile Pouzet
- Fédération de Recherches Agrobiosciences, Interactions et Biodiversité, Plateforme d’Imagerie TRI, CNRS - UPSCastanet-TolosanFrance
| | - Marie-Christine Auriac
- The Laboratory of Plant-Microbe InteractionsUniversité de Toulouse, INRA, CNRSCastanet-TolosanFrance
- Fédération de Recherches Agrobiosciences, Interactions et Biodiversité, Plateforme d’Imagerie TRI, CNRS - UPSCastanet-TolosanFrance
| | - Chaitanya S Gokhale
- Research Group for Theoretical Models of Eco-evolutionary Dynamics, Department of Evolutionary TheoryMax Planck Institute for Evolutionary BiologyPlönGermany
| | - Catherine Masson-Boivin
- The Laboratory of Plant-Microbe InteractionsUniversité de Toulouse, INRA, CNRSCastanet-TolosanFrance
| | - Delphine Capela
- The Laboratory of Plant-Microbe InteractionsUniversité de Toulouse, INRA, CNRSCastanet-TolosanFrance
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24
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Akimova ES, Gumenko RS, Vershinina ZR, Baymiev AK, Baymiev AK. Genetic markers for search of rhizobia based on symbiotic genes. Microbiology (Reading) 2017. [DOI: 10.1134/s0026261717050034] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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25
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Haskett TL, Ramsay JP, Bekuma AA, Sullivan JT, O'Hara GW, Terpolilli JJ. Evolutionary persistence of tripartite integrative and conjugative elements. Plasmid 2017; 92:30-36. [DOI: 10.1016/j.plasmid.2017.06.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Revised: 06/28/2017] [Accepted: 06/28/2017] [Indexed: 10/19/2022]
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26
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27
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Assembly and transfer of tripartite integrative and conjugative genetic elements. Proc Natl Acad Sci U S A 2016; 113:12268-12273. [PMID: 27733511 DOI: 10.1073/pnas.1613358113] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Integrative and conjugative elements (ICEs) are ubiquitous mobile genetic elements present as "genomic islands" within bacterial chromosomes. Symbiosis islands are ICEs that convert nonsymbiotic mesorhizobia into symbionts of legumes. Here we report the discovery of symbiosis ICEs that exist as three separate chromosomal regions when integrated in their hosts, but through recombination assemble as a single circular ICE for conjugative transfer. Whole-genome comparisons revealed exconjugants derived from nonsymbiotic mesorhizobia received three separate chromosomal regions from the donor Mesorhizobium ciceri WSM1271. The three regions were each bordered by two nonhomologous integrase attachment (att) sites, which together comprised three homologous pairs of attL and attR sites. Sequential recombination between each attL and attR pair produced corresponding attP and attB sites and joined the three fragments to produce a single circular ICE, ICEMcSym1271 A plasmid carrying the three attP sites was used to recreate the process of tripartite ICE integration and to confirm the role of integrase genes intS, intM, and intG in this process. Nine additional tripartite ICEs were identified in diverse mesorhizobia and transfer was demonstrated for three of them. The transfer of tripartite ICEs to nonsymbiotic mesorhizobia explains the evolution of competitive but suboptimal N2-fixing strains found in Western Australian soils. The unheralded existence of tripartite ICEs raises the possibility that multipartite elements reside in other organisms, but have been overlooked because of their unusual biology. These discoveries reveal mechanisms by which integrases dramatically manipulate bacterial genomes to allow cotransfer of disparate chromosomal regions.
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Barrett LG, Zee PC, Bever JD, Miller JT, Thrall PH. Evolutionary history shapes patterns of mutualistic benefit in
Acacia
–rhizobial interactions. Evolution 2016; 70:1473-85. [DOI: 10.1111/evo.12966] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Revised: 05/01/2016] [Accepted: 05/16/2016] [Indexed: 01/15/2023]
Affiliation(s)
| | - Peter C. Zee
- Department of Biology California State University Northridge California 91330
| | - James D. Bever
- Department of Ecology and Evolutionary Biology and Kansas Biological Survey University of Kansas Lawrence Kansas 66045
| | - Joseph T. Miller
- National Research Collections Australia CSIRO National Facilities and Collections Canberra ACT 2601 Australia
- Division of Environmental Biology National Science Foundation Arlington Virginia 22230
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29
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Baymiev AK, Ivanova ES, Gumenko RS, Chubukova OV, Baymiev AK. Analysis of symbiotic genes of leguminous root nodule bacteria grown in the southern urals. RUSS J GENET+ 2015. [DOI: 10.1134/s1022795415110034] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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30
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Remigi P, Zhu J, Young JPW, Masson-Boivin C. Symbiosis within Symbiosis: Evolving Nitrogen-Fixing Legume Symbionts. Trends Microbiol 2015; 24:63-75. [PMID: 26612499 DOI: 10.1016/j.tim.2015.10.007] [Citation(s) in RCA: 147] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Revised: 10/08/2015] [Accepted: 10/22/2015] [Indexed: 10/22/2022]
Abstract
Bacterial accessory genes are genomic symbionts with an evolutionary history and future that is different from that of their hosts. Packages of accessory genes move from strain to strain and confer important adaptations, such as interaction with eukaryotes. The ability to fix nitrogen with legumes is a remarkable example of a complex trait spread by horizontal transfer of a few key symbiotic genes, converting soil bacteria into legume symbionts. Rhizobia belong to hundreds of species restricted to a dozen genera of the Alphaproteobacteria and Betaproteobacteria, suggesting infrequent successful transfer between genera but frequent successful transfer within genera. Here we review the genetic and environmental conditions and selective forces that have shaped evolution of this complex symbiotic trait.
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Affiliation(s)
- Philippe Remigi
- INRA, Laboratoire des Interactions Plantes-Microorganismes (LIPM), UMR441, Castanet-Tolosan, France; CNRS, Laboratoire des Interactions Plantes-Microorganismes (LIPM), UMR2594, Castanet-Tolosan, France; New Zealand Institute for Advanced Study, Massey University, Auckland, New Zealand
| | - Jun Zhu
- Department of Microbiology, Nanjing Agricultural University, Nanjing, China; Department of Microbiology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - J Peter W Young
- Department of Biology, University of York, York YO10 5DD, UK
| | - Catherine Masson-Boivin
- INRA, Laboratoire des Interactions Plantes-Microorganismes (LIPM), UMR441, Castanet-Tolosan, France; CNRS, Laboratoire des Interactions Plantes-Microorganismes (LIPM), UMR2594, Castanet-Tolosan, France.
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31
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Lemaire B, Van Cauwenberghe J, Chimphango S, Stirton C, Honnay O, Smets E, Muasya AM. Recombination and horizontal transfer of nodulation and ACC deaminase (acdS) genes within Alpha- and Betaproteobacteria nodulating legumes of the Cape Fynbos biome. FEMS Microbiol Ecol 2015; 91:fiv118. [PMID: 26433010 DOI: 10.1093/femsec/fiv118] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/15/2015] [Indexed: 11/14/2022] Open
Abstract
The goal of this work is to study the evolution and the degree of horizontal gene transfer (HGT) within rhizobial genera of both Alphaproteobacteria (Mesorhizobium, Rhizobium) and Betaproteobacteria (Burkholderia), originating from South African Fynbos legumes. By using a phylogenetic approach and comparing multiple chromosomal and symbiosis genes, we revealed conclusive evidence of high degrees of horizontal transfer of nodulation genes among closely related species of both groups of rhizobia, but also among species with distant genetic backgrounds (Rhizobium and Mesorhizobium), underscoring the importance of lateral transfer of symbiosis traits as an important evolutionary force among rhizobia of the Cape Fynbos biome. The extensive exchange of symbiosis genes in the Fynbos is in contrast with a lack of significant events of HGT among Burkholderia symbionts from the South American Cerrado and Caatinga biome. Furthermore, homologous recombination among selected housekeeping genes had a substantial impact on sequence evolution within Burkholderia and Mesorhizobium. Finally, phylogenetic analyses of the non-symbiosis acdS gene in Mesorhizobium, a gene often located on symbiosis islands, revealed distinct relationships compared to the chromosomal and symbiosis genes, suggesting a different evolutionary history and independent events of gene transfer. The observed events of HGT and incongruence between different genes necessitate caution in interpreting topologies from individual data types.
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Affiliation(s)
- Benny Lemaire
- Department of Biological Sciences, University of Cape Town, Private Bag X3, Rondebosch 7701, Cape Town, South Africa Plant Conservation and Population Biology, KU Leuven, Kasteelpark Arenberg 31, PO Box 02435, 3001 Heverlee, Belgium
| | - Jannick Van Cauwenberghe
- Plant Conservation and Population Biology, KU Leuven, Kasteelpark Arenberg 31, PO Box 02435, 3001 Heverlee, Belgium Centre of Microbial and Plant Genetics, KU Leuven, Kasteelpark Arenberg 20, B-3001 Leuven, Belgium
| | - Samson Chimphango
- Department of Biological Sciences, University of Cape Town, Private Bag X3, Rondebosch 7701, Cape Town, South Africa
| | - Charles Stirton
- Department of Biological Sciences, University of Cape Town, Private Bag X3, Rondebosch 7701, Cape Town, South Africa
| | - Olivier Honnay
- Plant Conservation and Population Biology, KU Leuven, Kasteelpark Arenberg 31, PO Box 02435, 3001 Heverlee, Belgium
| | - Erik Smets
- Plant Conservation and Population Biology, KU Leuven, Kasteelpark Arenberg 31, PO Box 02435, 3001 Heverlee, Belgium Naturalis Biodiversity Center, Leiden University, 2300 RA Leiden, the Netherlands
| | - A Muthama Muasya
- Department of Biological Sciences, University of Cape Town, Private Bag X3, Rondebosch 7701, Cape Town, South Africa
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Kumar N, Lad G, Giuntini E, Kaye ME, Udomwong P, Shamsani NJ, Young JPW, Bailly X. Bacterial genospecies that are not ecologically coherent: population genomics of Rhizobium leguminosarum. Open Biol 2015; 5:140133. [PMID: 25589577 PMCID: PMC4313370 DOI: 10.1098/rsob.140133] [Citation(s) in RCA: 105] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Biological species may remain distinct because of genetic isolation or ecological adaptation, but these two aspects do not always coincide. To establish the nature of the species boundary within a local bacterial population, we characterized a sympatric population of the bacterium Rhizobium leguminosarum by genomic sequencing of 72 isolates. Although all strains have 16S rRNA typical of R. leguminosarum, they fall into five genospecies by the criterion of average nucleotide identity (ANI). Many genes, on plasmids as well as the chromosome, support this division: recombination of core genes has been largely within genospecies. Nevertheless, variation in ecological properties, including symbiotic host range and carbon-source utilization, cuts across these genospecies, so that none of these phenotypes is diagnostic of genospecies. This phenotypic variation is conferred by mobile genes. The genospecies meet the Mayr criteria for biological species in respect of their core genes, but do not correspond to coherent ecological groups, so periodic selection may not be effective in purging variation within them. The population structure is incompatible with traditional ‘polyphasic taxonomy′ that requires bacterial species to have both phylogenetic coherence and distinctive phenotypes. More generally, genomics has revealed that many bacterial species share adaptive modules by horizontal gene transfer, and we envisage a more consistent taxonomic framework that explicitly recognizes this. Significant phenotypes should be recognized as ‘biovars' within species that are defined by core gene phylogeny.
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Affiliation(s)
- Nitin Kumar
- Department of Biology, University of York, York YO10 5DD, UK
| | - Ganesh Lad
- Department of Biology, University of York, York YO10 5DD, UK
| | - Elisa Giuntini
- Department of Biology, University of York, York YO10 5DD, UK
| | - Maria E Kaye
- Department of Biology, University of York, York YO10 5DD, UK
| | | | | | - J Peter W Young
- Department of Biology, University of York, York YO10 5DD, UK
| | - Xavier Bailly
- Department of Biology, University of York, York YO10 5DD, UK
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33
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Parker MA, Jankowiak JG, Landrigan GK. Diversifying selection by Desmodiinae legume species onBradyrhizobiumsymbionts. FEMS Microbiol Ecol 2015; 91:fiv075. [DOI: 10.1093/femsec/fiv075] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/24/2015] [Indexed: 11/14/2022] Open
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Parker MA, Rousteau A. Mosaic origins of Bradyrhizobium legume symbionts on the Caribbean island of Guadeloupe. Mol Phylogenet Evol 2014; 77:110-5. [DOI: 10.1016/j.ympev.2014.04.011] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2014] [Revised: 04/04/2014] [Accepted: 04/08/2014] [Indexed: 11/28/2022]
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35
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Differing courses of genetic evolution of Bradyrhizobium inoculants as revealed by long-term molecular tracing in Acacia mangium plantations. Appl Environ Microbiol 2014; 80:5709-16. [PMID: 25002434 DOI: 10.1128/aem.02007-14] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Introducing nitrogen-fixing bacteria as an inoculum in association with legume crops is a common practice in agriculture. However, the question of the evolution of these introduced microorganisms remains crucial, both in terms of microbial ecology and agronomy. We explored this question by analyzing the genetic and symbiotic evolution of two Bradyrhizobium strains inoculated on Acacia mangium in Malaysia and Senegal 15 and 5 years, respectively, after their introduction. Based on typing of several loci, we showed that these two strains, although closely related and originally sampled in Australia, evolved differently. One strain was recovered in soil with the same five loci as the original isolate, whereas the symbiotic cluster of the other strain was detected with no trace of the three housekeeping genes of the original inoculum. Moreover, the nitrogen fixation efficiency was variable among these isolates (either recombinant or not), with significantly high, low, or similar efficiencies compared to the two original strains and no significant difference between recombinant and nonrecombinant isolates. These data suggested that 15 years after their introduction, nitrogen-fixing bacteria remain in the soil but that closely related inoculant strains may not evolve in the same way, either genetically or symbiotically. In a context of increasing agronomical use of microbial inoculants (for biological control, nitrogen fixation, or plant growth promotion), this result feeds the debate on the consequences associated with such practices.
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Horn K, Parker IM, Malek W, Rodríguez-Echeverría S, Parker MA. Disparate origins ofBradyrhizobiumsymbionts for invasive populations ofCytisus scoparius(Leguminosae) in North America. FEMS Microbiol Ecol 2014; 89:89-98. [DOI: 10.1111/1574-6941.12335] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2013] [Revised: 03/24/2014] [Accepted: 03/26/2014] [Indexed: 11/27/2022] Open
Affiliation(s)
- Kevin Horn
- Department of Biological Sciences; State University of New York; Binghamton NY USA
| | - Ingrid M. Parker
- Department of Ecology and Evolutionary Biology; University of California; Santa Cruz CA USA
| | - Wanda Malek
- Department of Genetics and Microbiology; Marie Curie-Sklodowska University; Lublin Poland
| | | | - Matthew A. Parker
- Department of Biological Sciences; State University of New York; Binghamton NY USA
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37
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Laranjo M, Alexandre A, Oliveira S. Legume growth-promoting rhizobia: An overview on the Mesorhizobium genus. Microbiol Res 2014; 169:2-17. [DOI: 10.1016/j.micres.2013.09.012] [Citation(s) in RCA: 167] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2013] [Revised: 09/16/2013] [Accepted: 09/21/2013] [Indexed: 11/24/2022]
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38
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Reeve W, Nandasena K, Yates R, Tiwari R, O’Hara G, Ninawi M, Chertkov O, Goodwin L, Bruce D, Detter C, Tapia R, Han S, Woyke T, Pitluck S, Nolan M, Land M, Copeland A, Liolios K, Pati A, Mavromatis K, Markowitz V, Kyrpides N, Ivanova N, Goodwin L, Meenakshi U, Howieson J. Complete genome sequence of Mesorhizobium opportunistum type strain WSM2075(T.). Stand Genomic Sci 2013; 9:294-303. [PMID: 24976886 PMCID: PMC4062634 DOI: 10.4056/sigs.4538264] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Mesorhizobium opportunistum strain WSM2075(T) was isolated in Western Australia in 2000 from root nodules of the pasture legume Biserrula pelecinus that had been inoculated with M. ciceri bv. biserrulae WSM1271. WSM2075(T) is an aerobic, motile, Gram negative, non-spore-forming rod that has gained the ability to nodulate B. pelecinus but is completely ineffective in N2 fixation with this host. This report reveals that the genome of M. opportunistum strain WSM2075(T) contains a chromosome of size 6,884,444 bp, encoding 6,685 protein-coding genes and 62 RNA-only encoding genes. The genome contains no plasmids, but does harbor a 455.7 kb genomic island from Mesorhizobium ciceri bv. biserrulae WSM1271 that has been integrated into a phenylalanine-tRNA gene.
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Affiliation(s)
- Wayne Reeve
- Centre for Rhizobium Studies, Murdoch University, Western Australia, Australia
| | - Kemanthi Nandasena
- Centre for Rhizobium Studies, Murdoch University, Western Australia, Australia
| | - Ron Yates
- Centre for Rhizobium Studies, Murdoch University, Western Australia, Australia
- Department of Agriculture and Food, Western Australia, Australia
| | - Ravi Tiwari
- Centre for Rhizobium Studies, Murdoch University, Western Australia, Australia
| | - Graham O’Hara
- Centre for Rhizobium Studies, Murdoch University, Western Australia, Australia
| | - Mohamed Ninawi
- Centre for Rhizobium Studies, Murdoch University, Western Australia, Australia
| | - Olga Chertkov
- Los Alamos National Laboratory, Bioscience Division, Los Alamos, New Mexico, USA
| | - Lynne Goodwin
- Los Alamos National Laboratory, Bioscience Division, Los Alamos, New Mexico, USA
| | - David Bruce
- Los Alamos National Laboratory, Bioscience Division, Los Alamos, New Mexico, USA
| | - Chris Detter
- Los Alamos National Laboratory, Bioscience Division, Los Alamos, New Mexico, USA
| | - Roxanne Tapia
- Los Alamos National Laboratory, Bioscience Division, Los Alamos, New Mexico, USA
| | - Shunseng Han
- Los Alamos National Laboratory, Bioscience Division, Los Alamos, New Mexico, USA
| | - Tanja Woyke
- DOE Joint Genome Institute, Walnut Creek, California, USA
| | - Sam Pitluck
- DOE Joint Genome Institute, Walnut Creek, California, USA
| | - Matt Nolan
- DOE Joint Genome Institute, Walnut Creek, California, USA
| | - Miriam Land
- Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
| | - Alex Copeland
- DOE Joint Genome Institute, Walnut Creek, California, USA
| | | | - Amrita Pati
- DOE Joint Genome Institute, Walnut Creek, California, USA
| | | | - Victor Markowitz
- Biological Data Management and Technology Center, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Nikos Kyrpides
- DOE Joint Genome Institute, Walnut Creek, California, USA
| | | | - Lynne Goodwin
- DOE Joint Genome Institute, Walnut Creek, California, USA
| | - Uma Meenakshi
- Centre for Rhizobium Studies, Murdoch University, Western Australia, Australia
| | - John Howieson
- Centre for Rhizobium Studies, Murdoch University, Western Australia, Australia
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Reeve W, Nandasena K, Yates R, Tiwari R, O’Hara G, Ninawi M, Gu W, Goodwin L, Detter C, Tapia R, Han C, Copeland A, Liolios K, Chen A, Markowitz V, Pati A, Mavromatis K, Woyke T, Kyrpides N, Ivanova N, Howieson J. Complete genome sequence of Mesorhizobium australicum type strain (WSM2073T). Stand Genomic Sci 2013. [DOI: 10.4056/sigs] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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40
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Reeve W, Nandasena K, Yates R, Tiwari R, O'Hara G, Ninawi M, Gu W, Goodwin L, Detter C, Tapia R, Han C, Copeland A, Liolios K, Chen A, Markowitz V, Pati A, Mavromatis K, Woyke T, Kyrpides N, Ivanova N, Howieson J. Complete genome sequence of Mesorhizobium australicum type strain (WSM2073(T)). Stand Genomic Sci 2013; 9:410-9. [PMID: 24976896 PMCID: PMC4062642 DOI: 10.4056/sigs.4568282] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Mesorhizobium australicum strain WSM2073T was isolated from root nodules on the pasture legume Biserrula pelecinus growing in Australia in 2000. This aerobic, motile, gram negative, non-spore-forming rod is poorly effective in N2 fixation on B. pelecinus and has gained the ability to nodulate B. pelecinus following in situ lateral transfer of a symbiosis island from the original inoculant strain for this legume, Mesorhizobium ciceri bv. biserrulae WSM1271. We describe that the genome size of M. australicum strain WSM2073T is 6,200,534 bp encoding 6,013 protein-coding genes and 67 RNA-only encoding genes. This genome does not contain any plasmids but has a 455.7 kb genomic island from Mesorhizobium ciceri bv. biserrulae WSM1271 that has been integrated into a phenylalanine-tRNA gene.
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Affiliation(s)
- Wayne Reeve
- Centre for Rhizobium Studies, Murdoch University, Western Australia, Australia
| | - Kemanthi Nandasena
- Centre for Rhizobium Studies, Murdoch University, Western Australia, Australia
| | - Ron Yates
- Centre for Rhizobium Studies, Murdoch University, Western Australia, Australia ; Department of Agriculture and Food, Western Australia, Australia
| | - Ravi Tiwari
- Centre for Rhizobium Studies, Murdoch University, Western Australia, Australia
| | - Graham O'Hara
- Centre for Rhizobium Studies, Murdoch University, Western Australia, Australia
| | - Mohamed Ninawi
- Centre for Rhizobium Studies, Murdoch University, Western Australia, Australia
| | - Wei Gu
- Los Alamos National Laboratory, Bioscience Division, Los Alamos, New Mexico, USA
| | - Lynne Goodwin
- Los Alamos National Laboratory, Bioscience Division, Los Alamos, New Mexico, USA
| | - Chris Detter
- Los Alamos National Laboratory, Bioscience Division, Los Alamos, New Mexico, USA
| | - Roxanne Tapia
- Los Alamos National Laboratory, Bioscience Division, Los Alamos, New Mexico, USA
| | - Cliff Han
- Los Alamos National Laboratory, Bioscience Division, Los Alamos, New Mexico, USA
| | - Alex Copeland
- DOE Joint Genome Institute, Walnut Creek, California, USA
| | | | - Amy Chen
- Biological Data Management and Technology Center, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Victor Markowitz
- Biological Data Management and Technology Center, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Amrita Pati
- DOE Joint Genome Institute, Walnut Creek, California, USA
| | | | - Tanja Woyke
- DOE Joint Genome Institute, Walnut Creek, California, USA
| | - Nikos Kyrpides
- DOE Joint Genome Institute, Walnut Creek, California, USA
| | | | - John Howieson
- Centre for Rhizobium Studies, Murdoch University, Western Australia, Australia
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Terpolilli JJ, Hood GA, Poole PS. What determines the efficiency of N(2)-fixing Rhizobium-legume symbioses? Adv Microb Physiol 2012; 60:325-89. [PMID: 22633062 DOI: 10.1016/b978-0-12-398264-3.00005-x] [Citation(s) in RCA: 88] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Biological nitrogen fixation is vital to nutrient cycling in the biosphere and is the major route by which atmospheric dinitrogen (N(2)) is reduced to ammonia. The largest single contribution to biological N(2) fixation is carried out by rhizobia, which include a large group of both alpha and beta-proteobacteria, almost exclusively in association with legumes. Rhizobia must compete to infect roots of legumes and initiate a signaling dialog with host plants that leads to nodule formation. The most common form of infection involves the growth of rhizobia down infection threads which are laid down by the host plant. Legumes form either indeterminate or determinate types of nodules, with these groups differing widely in nodule morphology and often in the developmental program by which rhizobia form N(2) fixing bacteroids. In particular, indeterminate legumes from the inverted repeat-lacking clade (IRLC) (e.g., peas, vetch, alfalfa, medics) produce a cocktail of antimicrobial peptides which cause endoreduplication of the bacterial genome and force rhizobia into a nongrowing state. Bacteroids often become dependent on the plant for provision of key cofactors, such as homocitrate needed for nitrogenase activity or for branched chain amino acids. This has led to the suggestion that bacteroids at least from the IRLC can be considered as ammoniaplasts, where they are effectively facultative plant organelles. A low O(2) tension is critical both to induction of genes needed for N(2) fixation and to the subsequent exchange of nutrient between plants and bacteroids. To achieve high rates of N(2) fixation, the legume host and Rhizobium must be closely matched not only for infection, but for optimum development, nutrient exchange, and N(2) fixation. In this review, we consider the multiple steps of selection and bacteroid development and how these alter the overall efficiency of N(2) fixation.
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Affiliation(s)
- Jason J Terpolilli
- Department of Molecular Microbiology, John Innes Centre, Norwich Research Park, Norwich, UK
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Nascimento FX, Brígido C, Glick BR, Oliveira S. ACC deaminase genes are conserved amongMesorhizobiumspecies able to nodulate the same host plant. FEMS Microbiol Lett 2012; 336:26-37. [DOI: 10.1111/j.1574-6968.2012.02648.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2012] [Revised: 07/06/2012] [Accepted: 07/27/2012] [Indexed: 11/28/2022] Open
Affiliation(s)
- Francisco X. Nascimento
- Laboratório de Microbiologia do Solo; I.C.A.A.M., Instituto de Ciências Agrárias e Ambientais Mediterrânicas, Universidade de Évora; Évora; Portugal
| | - Clarisse Brígido
- Laboratório de Microbiologia do Solo; I.C.A.A.M., Instituto de Ciências Agrárias e Ambientais Mediterrânicas, Universidade de Évora; Évora; Portugal
| | - Bernard R. Glick
- Department of Biology; University of Waterloo; Waterloo; ON; Canada
| | - Solange Oliveira
- Laboratório de Microbiologia do Solo; I.C.A.A.M., Instituto de Ciências Agrárias e Ambientais Mediterrânicas, Universidade de Évora; Évora; Portugal
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Provorov NA, Andronov EE, Onishchuk OP, Kurchak ON, Chizhevskaya EP. Genetic structure of the introduced and local populations of Rhizobioum leguminosarum in plant-soil systems. Microbiology (Reading) 2012. [DOI: 10.1134/s0026261712020129] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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45
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Giusti MDLÁ, Pistorio M, Lozano MJ, Tejerizo GAT, Salas ME, Martini MC, López JL, Draghi WO, Del Papa MF, Pérez-Mendoza D, Sanjuán J, Lagares A. Genetic and functional characterization of a yet-unclassified rhizobial Dtr (DNA-transfer-and-replication) region from a ubiquitous plasmid conjugal system present in Sinorhizobium meliloti, in Sinorhizobium medicae, and in other nonrhizobial Gram-negative bacteria. Plasmid 2012; 67:199-210. [PMID: 22233546 DOI: 10.1016/j.plasmid.2011.12.010] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2011] [Revised: 11/24/2011] [Accepted: 12/01/2011] [Indexed: 11/15/2022]
Abstract
Rhizobia are Gram-negative bacteria that live in soils and associate with leguminous plants to establish nitrogen-fixing symbioses. The ability of these bacteria to undergo horizontal gene transfer (HGT) is thought to be one of the main features to explain both the origin of their symbiotic life-style and the plasticity and dynamics of their genomes. In our laboratory we have previously characterized at the species level the non-pSym plasmid mobilome in Sinorhizobium meliloti, the symbiont of Medicago spp., and have found a high incidence of conjugal activity in many plasmids (Pistorio et al., 2008). In this work we characterized the Dtr (DNA-transfer-and-replication) region of one of those plasmids, pSmeLPU88b. This mobilization region was found to represent a previously unclassified Dtr type in rhizobia (hereafter type-IV), highly ubiquitous in S. meliloti and found in other genera of Gram-negative bacteria as well; including Agrobacterium, Ochrobactrum, and Chelativorans. The oriT of the type-IV Dtr described here could be located by function within a DNA fragment of 278 bp, between the divergent genes parA and mobC. The phylogenetic analysis of the cognate relaxase MobZ indicated that this protein groups close to the previously defined MOB(P3) and MOB(P4) type of enzymes, but is located in a separate and novel cluster that we have designated MOB(P0). Noteworthy, MOB(P0) and MOB(P4) relaxases were frequently associated with plasmids present in rhizospheric soil bacteria. A comparison of the nod-gene locations with the phylogenetic topology of the rhizobial relaxases revealed that the symbiotic genes are found on diverse plasmids bearing any of the four Dtr types, thus indicating that pSym plasmids are not specifically associated with any particular mobilization system. Finally, we demonstrated that the type-IV Dtr promoted the mobilization of plasmids from S. meliloti to Sinorhizobium medicae as well as from these rhizobia to other bacteria by means of their own helper functions. The results present an as-yet-unclassified and seemingly ubiquitous conjugal system that provides a mechanistic support for the HGT between sympatric rhizobia of Medicago roots, and between other soil and rhizospheric bacteria.
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Affiliation(s)
- María de los Ángeles Giusti
- Instituto de Biotecnología y Biología Molecular (IBBM)-CCT-CONICET-La Plata, Departamento de Ciencias Biológicas, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, La Plata, Argentina
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Genetic diversity of root nodule bacteria nodulating Lotus corniculatus and Anthyllis vulneraria in Sweden. Syst Appl Microbiol 2011; 34:267-75. [DOI: 10.1016/j.syapm.2011.01.006] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2010] [Revised: 01/20/2011] [Accepted: 01/24/2011] [Indexed: 11/24/2022]
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Perrineau MM, Le Roux C, de Faria SM, de Carvalho Balieiro F, Galiana A, Prin Y, Béna G. Genetic diversity of symbiotic Bradyrhizobium elkanii populations recovered from inoculated and non-inoculated Acacia mangium field trials in Brazil. Syst Appl Microbiol 2011; 34:376-84. [PMID: 21531520 DOI: 10.1016/j.syapm.2011.03.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2011] [Revised: 03/10/2011] [Accepted: 03/11/2011] [Indexed: 10/18/2022]
Abstract
Acacia mangium is a legume tree native to Australasia. Since the eighties, it has been introduced into many tropical countries, especially in a context of industrial plantations. Many field trials have been set up to test the effects of controlled inoculation with selected symbiotic bacteria versus natural colonization with indigenous strains. In the introduction areas, A. mangium trees spontaneously nodulate with local and often ineffective bacteria. When inoculated, the persistence of inoculants and possible genetic recombination with local strains remain to be explored. The aim of this study was to describe the genetic diversity of bacteria spontaneously nodulating A. mangium in Brazil and to evaluate the persistence of selected strains used as inoculants. Three different sites, several hundred kilometers apart, were studied, with inoculated and non-inoculated plots in two of them. Seventy-nine strains were isolated from nodules and sequenced on three housekeeping genes (glnII, dnaK and recA) and one symbiotic gene (nodA). All but one of the strains belonged to the Bradyrhizobium elkanii species. A single case of housekeeping gene transfer was detected among the 79 strains, suggesting an extremely low rate of recombination within B. elkanii, whereas the nodulation gene nodA was found to be frequently transferred. The fate of the inoculant strains varied depending on the site, with a complete disappearance in one case, and persistence in another. We compared our results with the sister species Bradyrhizobium japonicum, both in terms of population genetics and inoculant strain destiny.
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Affiliation(s)
- M M Perrineau
- CIRAD, Laboratoire des Symbioses Tropicales & Méditerranéennes, Montpellier, France
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Stępkowski T, Zak M, Moulin L, Króliczak J, Golińska B, Narożna D, Safronova VI, Mądrzak CJ. Bradyrhizobium canariense and Bradyrhizobium japonicum are the two dominant rhizobium species in root nodules of lupin and serradella plants growing in Europe. Syst Appl Microbiol 2011; 34:368-75. [PMID: 21514760 DOI: 10.1016/j.syapm.2011.03.002] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2011] [Revised: 02/26/2011] [Accepted: 03/01/2011] [Indexed: 10/18/2022]
Abstract
Forty three Bradyrhizobium strains isolated in Poland from root nodules of lupin species (Lupinus albus, L. angustifolius and L. luteus), and pink serradella (Ornithopus sativus) were examined based on phylogenetic analyses of three housekeeping (atpD, glnII and recA) and nodulation (nodA) gene sequences. Additionally, seven strains originating from root-nodules of yellow serradella (O. compressus) from Asinara Island (Italy) were included in this study. Phylogenetic trees revealed that 15 serradella strains, including all yellow serradella isolates, and six lupin strains grouped in Bradyrhizobium canariense (BC) clade, whereas eight strains from pink serradella and 15 lupin strains were assigned to Bradyrhizobium japonicum (BJ1). Apparently, these species are the two dominant groups in soils of central Europe, in the nodules of lupin and serradella plants. Only three strains belonged to other chromosomal lineages: one formed a cluster that was sister to B. canariense, one strain grouped outside the branch formed by B. japonicum super-group, and one strain occupied a distant position in the genus Bradyrhizobium, clustering with strains of the Rhodopseudomonas genus. All strains in nodulation nodA gene tree grouped in a cluster referred to as Clade II, which is in line with earlier data on this clade dominance among Bradyrhizobium strains in Europe. The nodA tree revealed four well-supported subgroups within Clade II (II.1-II.4). Interestingly, all B. canariense strains clustered in subgroup II.1 whereas B. japonicum strains dominated subgroups II.2-II.4.
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Affiliation(s)
- Tomasz Stępkowski
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, 61-704 Poznań, Noskowskiego 12/14, Poland
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Xu L, Shi JF, Zhao P, Chen WM, Qin W, Tang M, Wei GH. Rhizobium sphaerophysae sp. nov., a novel species isolated from root nodules of Sphaerophysa salsula in China. Antonie van Leeuwenhoek 2011; 99:845-54. [PMID: 21308410 DOI: 10.1007/s10482-011-9559-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2010] [Accepted: 01/24/2011] [Indexed: 10/18/2022]
Abstract
Four gram-negative, aerobic, motile, non-spore, forming rods with a wide pH and temperature range for growth (pH 7.0-11.0, optimum pH 8.0; 20-45°C, optimum 28°C) strains were isolated from root nodules of Sphaerophysa salsula and characterized by means of a polyphasic approach. Phylogenetic analysis based on 16S rRNA gene sequences revealed that the four strains formed a new lineage related to the genus Rhizobium and the sequence similarities between the isolate and the most related type strain Rhizobium giardinii was 96.5%. These strains also formed a distinctive group from the reference strains for defined Rhizobium species based on housekeeping gene sequences (atpD and recA), BOX-PCR fingerprinting, phenotypic features and symbiotic properties. The representative strain CCNWGS0238(T) has DNA-DNA relatedness of less than 33.4% with the most closely related species R. giardinii. It is therefore proposed as a new species, Rhizobium sphaerophysae sp. nov., with isolate CCNWGS0238(T) (=ACCC17498(T) = HAMBI3074(T)) as the type strain.
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Affiliation(s)
- Lin Xu
- College of Life Sciences, Shaanxi Key Laboratory of Molecular Biology for Agriculture, Northwest A & F University, Yangling Shaanxi, 712100, China
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Experimental evidences of pSym transfer in a native peanut-associated rhizobia. Microbiol Res 2010; 165:505-15. [DOI: 10.1016/j.micres.2009.08.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2009] [Revised: 08/11/2009] [Accepted: 08/16/2009] [Indexed: 11/19/2022]
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