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Nogueira CB, Menéndez E, Ramírez-Bahena MH, Velázquez E, Peix Á, Mateos PF, Scotti MR. The N-fixing legume Periandra mediterranea constrains the invasion of an exotic grass (Melinis minutiflora P. Beauv) by altering soil N cycling. Sci Rep 2019; 9:11033. [PMID: 31363104 PMCID: PMC6667476 DOI: 10.1038/s41598-019-47380-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Accepted: 07/10/2019] [Indexed: 11/08/2022] Open
Abstract
Melinis minutiflora is an invasive species that threatens the biodiversity of the endemic vegetation of the campo rupestre biome in Brazil, displacing the native vegetation and favouring fire spread. As M. minutiflora invasion has been associated with a high nitrogen (N) demand, we assessed changes in N cycle under four treatments: two treatments with contrasting invasion levels (above and below 50%) and two un-invaded control treatments with native vegetation, in the presence or absence of the leguminous species Periandra mediterranea. This latter species was considered to be the main N source in this site due to its ability to fix N2 in association with Bradyrhizobia species. Soil proteolytic activity was high in treatments with P. mediterranea and in those severely invaded, but not in the first steps of invasion. While ammonium was the N-chemical species dominant in plots with native species, including P.mediterranea, soil nitrate prevailed only in fully invaded plots due to the stimulation of the nitrifying bacterial (AOB) and archaeal (AOA) populations carrying the amoA gene. However, in the presence of P. mediterranea, either in the beginning of the invasion or in uninvaded plots, we observed an inhibition of the nitrifying microbial populations and nitrate formation, suggesting that this is a biotic resistance strategy elicited by P. mediterranea to compete with M. minutiflora. Therefore, the inhibition of proteolytic activity and the nitrification process were the strategies elicited by P.mediterranea to constrain M.munitiflora invasion.
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Affiliation(s)
- Carina B Nogueira
- Department of Botany, Institute of Biological Science/Federal University of Minas Gerais, Belo Horizonte, Brazil
| | - Esther Menéndez
- Departamento de Microbiología y Genética and Instituto Hispanoluso de Investigaciones Agrarias (CIALE), Universidad de Salamanca, Salamanca, Spain
- ICAAM (Institute of Mediterranean Agriculture and Environmental Sciences), University of Évora-Núcleo da Mitra, Évora, Portugal
| | | | - Encarna Velázquez
- Departamento de Microbiología y Genética and Instituto Hispanoluso de Investigaciones Agrarias (CIALE), Universidad de Salamanca, Salamanca, Spain
- Unidad Asociada Universidad de Salamanca- CSIC 'Interacción Planta-Microorganismo', Salamanca, Spain
| | - Álvaro Peix
- Instituto de Recursos Naturales y Agrobiología (IRNASA-CSIC), Cordel de Merinas 40-52, 37008, Salamanca, Spain
- Unidad Asociada Universidad de Salamanca- CSIC 'Interacción Planta-Microorganismo', Salamanca, Spain
| | - Pedro F Mateos
- Departamento de Microbiología y Genética and Instituto Hispanoluso de Investigaciones Agrarias (CIALE), Universidad de Salamanca, Salamanca, Spain
- Unidad Asociada Universidad de Salamanca- CSIC 'Interacción Planta-Microorganismo', Salamanca, Spain
| | - Maria Rita Scotti
- Department of Botany, Institute of Biological Science/Federal University of Minas Gerais, Belo Horizonte, Brazil.
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Flores-Félix JD, Sánchez-Juanes F, García-Fraile P, Valverde A, Mateos PF, Gónzalez-Buitrago JM, Velázquez E, Rivas R. Phaseolus vulgaris is nodulated by the symbiovar viciae of several genospecies of Rhizobium laguerreae complex in a Spanish region where Lens culinaris is the traditionally cultivated legume. Syst Appl Microbiol 2019; 42:240-247. [DOI: 10.1016/j.syapm.2018.10.009] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2018] [Revised: 10/25/2018] [Accepted: 10/26/2018] [Indexed: 11/30/2022]
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3
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Robledo M, Menéndez E, Jiménez-Zurdo JI, Rivas R, Velázquez E, Martínez-Molina E, Oldroyd G, Mateos PF. Heterologous Expression of Rhizobial CelC2 Cellulase Impairs Symbiotic Signaling and Nodulation in Medicago truncatula. Mol Plant Microbe Interact 2018; 31:568-575. [PMID: 29334470 DOI: 10.1094/mpmi-11-17-0265-r] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The infection of legume plants by rhizobia is tightly regulated to ensure accurate bacterial penetration, infection, and development of functionally efficient nitrogen-fixing root nodules. Rhizobial Nod factors (NF) have key roles in the elicitation of nodulation signaling. Infection of white clover roots also involves the tightly regulated specific breakdown of the noncrystalline apex of cell walls in growing root hairs, which is mediated by Rhizobium leguminosarum bv. trifolii cellulase CelC2. Here, we have analyzed the impact of this endoglucanase on symbiotic signaling in the model legume Medicago truncatula. Ensifer meliloti constitutively expressing celC gene exhibited delayed nodulation and elicited aberrant ineffective nodules, hampering plant growth in the absence of nitrogen. Cotreatment of roots with NF and CelC2 altered Ca2+ spiking in root hairs and induction of the early nodulin gene ENOD11. Our data suggest that CelC2 alters early signaling between partners in the rhizobia-legume interaction.
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Affiliation(s)
- Marta Robledo
- 1 Departamento de Microbiología y Genética, Centro Hispano-Luso de Investigaciones Agrarias, Universidad de Salamanca, Unidad Asociada CSIC/USAL, Spain
- 2 Estación Experimental del Zaidín, CSIC, Granada, Spain; and
| | - Esther Menéndez
- 1 Departamento de Microbiología y Genética, Centro Hispano-Luso de Investigaciones Agrarias, Universidad de Salamanca, Unidad Asociada CSIC/USAL, Spain
| | | | - Raúl Rivas
- 1 Departamento de Microbiología y Genética, Centro Hispano-Luso de Investigaciones Agrarias, Universidad de Salamanca, Unidad Asociada CSIC/USAL, Spain
| | - Encarna Velázquez
- 1 Departamento de Microbiología y Genética, Centro Hispano-Luso de Investigaciones Agrarias, Universidad de Salamanca, Unidad Asociada CSIC/USAL, Spain
| | - Eustoquio Martínez-Molina
- 1 Departamento de Microbiología y Genética, Centro Hispano-Luso de Investigaciones Agrarias, Universidad de Salamanca, Unidad Asociada CSIC/USAL, Spain
| | - Giles Oldroyd
- 3 Department of Cell and Development Biology, John Innes Centre, Norwich, U.K
| | - Pedro F Mateos
- 1 Departamento de Microbiología y Genética, Centro Hispano-Luso de Investigaciones Agrarias, Universidad de Salamanca, Unidad Asociada CSIC/USAL, Spain
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4
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Jiménez-Gómez A, Flores-Félix JD, García-Fraile P, Mateos PF, Menéndez E, Velázquez E, Rivas R. Probiotic activities of Rhizobium laguerreae on growth and quality of spinach. Sci Rep 2018; 8:295. [PMID: 29321563 PMCID: PMC5762915 DOI: 10.1038/s41598-017-18632-z] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Accepted: 12/14/2017] [Indexed: 12/15/2022] Open
Abstract
The growing interest in a healthy lifestyle and in environmental protection is changing habits regarding food consumption and agricultural practices. Good agricultural practice is indispensable, particularly for raw vegetables, and can include the use of plant probiotic bacteria for the purpose of biofertilization. In this work we analysed the probiotic potential of the rhizobial strain PEPV40, identified as Rhizobium laguerreae through the analysis of the recA and atpD genes, on the growth of spinach plants. This strain presents several in vitro plant growth promotion mechanisms, such as phosphate solubilisation and the production of indole acetic acid and siderophores. The strain PEPV40 produces cellulose and forms biofilms on abiotic surfaces. GFP labelling of this strain showed that PEPV40 colonizes the roots of spinach plants, forming microcolonies typical of biofilm initiation. Inoculation with this strain significantly increases several vegetative parameters such as leaf number, size and weight, as well as chlorophyll and nitrogen contents. Therefore, our findings indicate, for the first time, that Rhizobium laguerreae is an excellent plant probiotic, which increases the yield and quality of spinach, a vegetable that is increasingly being consumed raw worldwide.
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Affiliation(s)
- Alejandro Jiménez-Gómez
- Microbiology and Genetics Department, University of Salamanca, 37007, Salamanca, Spain
- Spanish-Portuguese Institute for Agricultural Research (CIALE), Villamayor, Salamanca, Spain
| | - José David Flores-Félix
- Microbiology and Genetics Department, University of Salamanca, 37007, Salamanca, Spain
- Spanish-Portuguese Institute for Agricultural Research (CIALE), Villamayor, Salamanca, Spain
| | - Paula García-Fraile
- Microbiology and Genetics Department, University of Salamanca, 37007, Salamanca, Spain
- Institute of Microbiology ASCR,v.v.i., Vídeňská 1083, 142 20, Prague, Czech Republic
| | - Pedro F Mateos
- Microbiology and Genetics Department, University of Salamanca, 37007, Salamanca, Spain
- Spanish-Portuguese Institute for Agricultural Research (CIALE), Villamayor, Salamanca, Spain
- Associated R&D Unit, USAL-CSIC (IRNASA), Salamanca, Spain
| | - Esther Menéndez
- Microbiology and Genetics Department, University of Salamanca, 37007, Salamanca, Spain
- ICAAM - Instituto de Ciências Agrárias e Ambientais Mediterrânicas, Universidade de Évora, Pólo da Mitra, Ap. 94, 7002-554, Évora, Portugal
| | - Encarna Velázquez
- Microbiology and Genetics Department, University of Salamanca, 37007, Salamanca, Spain
- Spanish-Portuguese Institute for Agricultural Research (CIALE), Villamayor, Salamanca, Spain
- Associated R&D Unit, USAL-CSIC (IRNASA), Salamanca, Spain
| | - Raúl Rivas
- Microbiology and Genetics Department, University of Salamanca, 37007, Salamanca, Spain.
- Spanish-Portuguese Institute for Agricultural Research (CIALE), Villamayor, Salamanca, Spain.
- Associated R&D Unit, USAL-CSIC (IRNASA), Salamanca, Spain.
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5
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Cruz-González X, Laza-Pérez N, Mateos PF, Rivas R. Analysis and effect of the use of biofertilizers on Trifolium rubens L., a preferential attention species in Castile and Leon, Spain, with the aim of increasing the plants conservation status. AIMS Microbiol 2017; 3:733-746. [PMID: 31294185 PMCID: PMC6604960 DOI: 10.3934/microbiol.2017.4.733] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Accepted: 08/14/2017] [Indexed: 11/18/2022] Open
Abstract
Trifolium rubens L. is a leguminous plant "Preferential Attention", according to the Catalog of Protected Flora of Castile and Leon (Spain). In this study we aimed to analyze the potential of three bacterial strains of the genus Rhizobium to improve the growth and development of this plant. All three strains produced 3-indoleacetic acid (IAA), but the strain ATCC 14480 produced the most. In addition, all strains produced biofilms and cellulases, although in different quantities. The synthesis of these products has been described as being related to the processes of the adherence of bacteria to the plant root surface and their entrance into the plant, respectively. In addition, in vitro assays and assays conducted under controlled and sterile conditions were performed, showing that the three strains were capable of nodulating T. rubens L. and effectively fixed nitrogen for the plant. These results were corroborated by morphological and histological analysis of nodules. Finally, greenhouse assays determined the effects of the strains under more competitive conditions, and it was concluded that inoculated plants presented greater lengths and weights, both aerial and radicular, and also chlorophyll and nitrogen content compared to the uninoculated controls.
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Affiliation(s)
- Xavier Cruz-González
- Department of Microbiology and Genetics, University of Salamanca, Salamanca, Castile & Leon, Spain.,Spanish-Portuguese Institute for Agricultural Research (CIALE), Salamanca, Castile & Leon, Spain
| | - Nereha Laza-Pérez
- Department of Microbiology and Genetics, University of Salamanca, Salamanca, Castile & Leon, Spain
| | - Pedro F Mateos
- Department of Microbiology and Genetics, University of Salamanca, Salamanca, Castile & Leon, Spain.,Spanish-Portuguese Institute for Agricultural Research (CIALE), Salamanca, Castile & Leon, Spain.,Associated I + D Unit, USAL-CSIC (IRNASA), Salamanca, Castile & Leon, Spain
| | - Raúl Rivas
- Department of Microbiology and Genetics, University of Salamanca, Salamanca, Castile & Leon, Spain.,Spanish-Portuguese Institute for Agricultural Research (CIALE), Salamanca, Castile & Leon, Spain.,Associated I + D Unit, USAL-CSIC (IRNASA), Salamanca, Castile & Leon, Spain
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6
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Marcos-García M, Menéndez E, Ramírez-Bahena MH, Mateos PF, Peix Á, Velazquez E, Rivas R. Mesorhizobium helmanticense sp. nov., isolated from Lotus corniculatus nodules. Int J Syst Evol Microbiol 2017; 67:2301-2305. [DOI: 10.1099/ijsem.0.001942] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Marta Marcos-García
- Departamento de Microbiología y Genética and Centro Hispanoluso de Investigaciones Agrarias (CIALE), Universidad de Salamanca, Salamanca, Spain
| | - Esther Menéndez
- Departamento de Microbiología y Genética and Centro Hispanoluso de Investigaciones Agrarias (CIALE), Universidad de Salamanca, Salamanca, Spain
| | | | - Pedro F. Mateos
- Departamento de Microbiología y Genética and Centro Hispanoluso de Investigaciones Agrarias (CIALE), Universidad de Salamanca, Salamanca, Spain
- Unidad Asociada Universidad de Salamanca-CSIC ‘Interacciones Planta-Microorganismo’, Salamanca, Spain
| | - Álvaro Peix
- IRNASA-CSIC, Salamanca, Spain
- Unidad Asociada Universidad de Salamanca-CSIC ‘Interacciones Planta-Microorganismo’, Salamanca, Spain
| | - Encarna Velazquez
- Departamento de Microbiología y Genética and Centro Hispanoluso de Investigaciones Agrarias (CIALE), Universidad de Salamanca, Salamanca, Spain
- Unidad Asociada Universidad de Salamanca-CSIC ‘Interacciones Planta-Microorganismo’, Salamanca, Spain
| | - Raúl Rivas
- Departamento de Microbiología y Genética and Centro Hispanoluso de Investigaciones Agrarias (CIALE), Universidad de Salamanca, Salamanca, Spain
- Unidad Asociada Universidad de Salamanca-CSIC ‘Interacciones Planta-Microorganismo’, Salamanca, Spain
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7
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Marcos-García M, García-Fraile P, Filipová A, Menéndez E, Mateos PF, Velázquez E, Cajthaml T, Rivas R. Mesorhizobium bacterial strains isolated from the legume Lotus corniculatus are an alternative source for the production of polyhydroxyalkanoates (PHAs) to obtain bioplastics. Environ Sci Pollut Res Int 2017; 24:17436-17445. [PMID: 28593540 DOI: 10.1007/s11356-017-9319-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2016] [Accepted: 05/19/2017] [Indexed: 06/07/2023]
Abstract
Polyhydroxyalkanoic acids (PHAs) are natural polyesters that can be used to produce bioplastics which are biodegradable. Numerous microorganisms accumulate PHAs as energy reserves. Combinations of different PHAs monomers lead to the production of bioplastics with very different properties. In the present work, we show the capability of strains belonging to various phylogenetic lineages within the genus Mesorhizobium, isolated from Lotus corniculatus nodules, to produce different PHA monomers. Among our strains, we found the production of 3-hydroxybutyrate, 3-hydroxyvalerate, 3-hydroxydodecanoate, and 3-hydroxyhexadecanoate. Most of the PHA-positive strains were phylogenetically related to the species M. jarvisii. However, our findings suggest that the ability to produce different monomers forming PHAs is strain-dependent.
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Affiliation(s)
- Marta Marcos-García
- Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain
- Instituto Hispano-Luso de Investigaciones Agrarias (CIALE), Salamanca, Spain
| | - Paula García-Fraile
- Mikrobiologický ústav, Akademie věd České republiky, Prague, Czech Republic.
| | - Alena Filipová
- Mikrobiologický ústav, Akademie věd České republiky, Prague, Czech Republic
- Přírodovědecká fakulta, Univerzita Karlova, Prague, Czech Republic
| | - Esther Menéndez
- Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain
- ICAAM - Instituto de Ciências Agrárias e Ambientais Mediterrânicas, Universidade de Évora, Évora, Portugal
| | - Pedro F Mateos
- Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain
- Instituto Hispano-Luso de Investigaciones Agrarias (CIALE), Salamanca, Spain
- Unidad Asociada Universidad de Salamanca-CSIC (IRNASA), Salamanca, Spain
| | - Encarna Velázquez
- Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain
- Instituto Hispano-Luso de Investigaciones Agrarias (CIALE), Salamanca, Spain
- Unidad Asociada Universidad de Salamanca-CSIC (IRNASA), Salamanca, Spain
| | - Tomáš Cajthaml
- Mikrobiologický ústav, Akademie věd České republiky, Prague, Czech Republic
- Přírodovědecká fakulta, Univerzita Karlova, Prague, Czech Republic
| | - Raúl Rivas
- Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain
- Instituto Hispano-Luso de Investigaciones Agrarias (CIALE), Salamanca, Spain
- Unidad Asociada Universidad de Salamanca-CSIC (IRNASA), Salamanca, Spain
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8
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Díez-Méndez A, Rivas R, Mateos PF, Martínez-Molina E, Santín PJ, Sánchez-Rodríguez JA, Velázquez E. Bacillus terrae sp. nov. isolated from Cistus ladanifer rhizosphere soil. Int J Syst Evol Microbiol 2017; 67:1478-1481. [PMID: 27983469 DOI: 10.1099/ijsem.0.001742] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A bacterial strain designated RA9T was isolated from a root of Cistus ladanifer in Spain. Phylogenetic analyses based on 16S rRNA gene sequences placed the isolate into the genus Bacillus with its closest relatives being Bacillus fortis R-6514T and Bacillus fordii R-7190T with 98.2 % similarity in both cases. DNA-DNA hybridization studies showed mean relatedness values of 29 and 30 %, respectively, between strain RA9T and the type strains of B. fortis and B. fordii. Cells of the isolate were Gram-stain-positive, motile, sporulating rods. Catalase and oxidase were positive. Gelatin, starch and casein were not hydrolysed. Menaquinone MK-7 was the only menaquinone detected and iso-C15 : 0 and anteiso-C15 : 0 were the major fatty acids. The polar lipid profile consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, one unidentified aminophospholipid, one unidentified phospholipid, one unidentifed glycolipid and one unidentified lipid. meso-Diaminopimelic acid was detected in the peptidoglycan. The DNA G+C content was 43.1 mol%. Phylogenetic, chemotaxonomic and phenotypic analyses showed that strain RA9T should be considered as representing a novel species of the genus Bacillus, for which the name Bacillus terrae sp. nov. is proposed. The type strain is RA9T (=LMG 29736T=CECT 9170T).
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Affiliation(s)
- Alexandra Díez-Méndez
- Departamento de Microbiología y Genética and Instituto Hispanoluso de Investigaciones Agrarias (CIALE), Universidad de Salamanca, Salamanca, Spain
| | - Raúl Rivas
- Departamento de Microbiología y Genética and Instituto Hispanoluso de Investigaciones Agrarias (CIALE), Universidad de Salamanca, Salamanca, Spain.,Unidad Asociada Grupo de Interacción Planta-Microorganismo Universidad de Salamanca-IRNASA-CSIC, Salamanca, Spain
| | - Pedro F Mateos
- Departamento de Microbiología y Genética and Instituto Hispanoluso de Investigaciones Agrarias (CIALE), Universidad de Salamanca, Salamanca, Spain.,Unidad Asociada Grupo de Interacción Planta-Microorganismo Universidad de Salamanca-IRNASA-CSIC, Salamanca, Spain
| | - Eustoquio Martínez-Molina
- Departamento de Microbiología y Genética and Instituto Hispanoluso de Investigaciones Agrarias (CIALE), Universidad de Salamanca, Salamanca, Spain.,Unidad Asociada Grupo de Interacción Planta-Microorganismo Universidad de Salamanca-IRNASA-CSIC, Salamanca, Spain
| | | | | | - Encarna Velázquez
- Departamento de Microbiología y Genética and Instituto Hispanoluso de Investigaciones Agrarias (CIALE), Universidad de Salamanca, Salamanca, Spain.,Unidad Asociada Grupo de Interacción Planta-Microorganismo Universidad de Salamanca-IRNASA-CSIC, Salamanca, Spain
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9
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Robledo M, Peregrina A, Millán V, García-Tomsig NI, Torres-Quesada O, Mateos PF, Becker A, Jiménez-Zurdo JI. A conserved α-proteobacterial small RNA contributes to osmoadaptation and symbiotic efficiency of rhizobia on legume roots. Environ Microbiol 2017; 19:2661-2680. [PMID: 28401641 DOI: 10.1111/1462-2920.13757] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Revised: 04/05/2017] [Accepted: 04/05/2017] [Indexed: 02/02/2023]
Abstract
Small non-coding RNAs (sRNAs) are expected to have pivotal roles in the adaptive responses underlying symbiosis of nitrogen-fixing rhizobia with legumes. Here, we provide primary insights into the function and activity mechanism of the Sinorhizobium meliloti trans-sRNA NfeR1 (Nodule Formation Efficiency RNA). Northern blot probing and transcription tracking with fluorescent promoter-reporter fusions unveiled high nfeR1 expression in response to salt stress and throughout the symbiotic interaction. The strength and differential regulation of nfeR1 transcription are conferred by a motif, which is conserved in nfeR1 promoter regions in α-proteobacteria. NfeR1 loss-of-function compromised osmoadaptation of free-living bacteria, whilst causing misregulation of salt-responsive genes related to stress adaptation, osmolytes catabolism and membrane trafficking. Nodulation tests revealed that lack of NfeR1 affected competitiveness, infectivity, nodule development and symbiotic efficiency of S. meliloti on alfalfa roots. Comparative computer predictions and a genetic reporter assay evidenced a redundant role of three identical NfeR1 unpaired anti Shine-Dalgarno motifs for targeting and downregulation of translation of multiple mRNAs from transporter genes. Our data provide genetic evidence of the hyperosmotic conditions of the endosymbiotic compartments. NfeR1-mediated gene regulation in response to this cue could contribute to coordinate nutrient uptake with the metabolic reprogramming concomitant to symbiotic transitions.
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Affiliation(s)
- Marta Robledo
- Grupo de Ecología Genética de la Rizosfera, Estación Experimental del Zaidín, CSIC, 18008 Granada, Spain
| | - Alexandra Peregrina
- Grupo de Ecología Genética de la Rizosfera, Estación Experimental del Zaidín, CSIC, 18008 Granada, Spain
| | - Vicenta Millán
- Grupo de Ecología Genética de la Rizosfera, Estación Experimental del Zaidín, CSIC, 18008 Granada, Spain
| | - Natalia I García-Tomsig
- Grupo de Ecología Genética de la Rizosfera, Estación Experimental del Zaidín, CSIC, 18008 Granada, Spain
| | - Omar Torres-Quesada
- Grupo de Ecología Genética de la Rizosfera, Estación Experimental del Zaidín, CSIC, 18008 Granada, Spain
| | - Pedro F Mateos
- Departamento de Microbiología y Genética and CIALE, Edificio Departamental, Campus Miguel de Unamuno, Universidad de Salamanca, 37007 Salamanca, Spain
| | - Anke Becker
- LOEWE Center for Synthetic Microbiology and Faculty of Biology, Philipps-Universität Marburg, 35043 Marburg, Germany
| | - José I Jiménez-Zurdo
- Grupo de Ecología Genética de la Rizosfera, Estación Experimental del Zaidín, CSIC, 18008 Granada, Spain
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10
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Ribeiro PCD, Menendez E, da Silva DL, Bonieck D, Ramírez-Bahena MH, Resende-Stoianoff MA, Peix A, Velázquez E, Mateos PF, Scotti MR. Invasion of the Brazilian campo rupestre by the exotic grass Melinis minutiflora is driven by the high soil N availability and changes in the N cycle. Sci Total Environ 2017; 577:202-211. [PMID: 27823824 DOI: 10.1016/j.scitotenv.2016.10.162] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Revised: 10/20/2016] [Accepted: 10/20/2016] [Indexed: 06/06/2023]
Abstract
The Serra do Rola Moça State Park (PESRM) in Minas Gerais State, Brazil is a preserved site representative of the campo rupestre biome over an ironstone outcrop that has a high level of plant diversity. Almost 60% of this grassy field has been invaded by the exotic molasses grass (Melinis minutiflora), which constitutes a severe threat to the biodiversity and survival of this biome, particularly due to the impacts of annual fires and inappropriate restoration interventions. Many invasive species exhibit a high demand for nitrogen (N). Hence, this work aimed to study the N cycle alterations promoted by M. minutiflora in a site of the campo rupestre, where the leguminous species Mimosa pogocephala was prevalent. The biome's soils exhibited a high natural N fertility and low C:N ratio. The main N source in this biome resulted from the biological N fixation performed by M. pogocephala associated with Burkholderia nodosa, as evidenced by the total leaf N content, leaf δ15N signature, nodule occupation and bacterial molecular identification analyses. The displacement of native species by molasses grass was associated with changes in the soil N forms, namely the nitrate increased as the ammonium decreased. The latter was the dominant N form in the native species plots, as observed in the soil analysis of total N, ammonium and nitrate contents. The dominant ammonium form was changed to the nitric form by the stimulation of ammonia-oxidising bacteria populations due to the invasive species. Therefore, the key mechanism behind the invasiveness of the exotic grass and the concomitant displacement of the native species may be associated with changes in the soil N chemical species. Based on this finding and on the high N-based soil fertility found in the campo rupestre N fertilisation procedures for restoration of invaded areas should be strictly avoided in this biome.
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Affiliation(s)
- Pâmella C D Ribeiro
- Departmento de Botânica - Universidade Federal de Minas Gerais, Av. Antonio Carlos 6627, Pampulha, Belo Horizonte, Minas Gerais CEP 31270901, Brazil
| | - Esther Menendez
- Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain
| | - Danielle L da Silva
- Departmento de Botânica - Universidade Federal de Minas Gerais, Av. Antonio Carlos 6627, Pampulha, Belo Horizonte, Minas Gerais CEP 31270901, Brazil; Departmento de Microbiologia-Universidade Federal de Minas Gerais, Av. Antonio Carlos 6627, Pampulha, Belo Horizonte, Minas Gerais CEP 31270901, Brazil
| | - Douglas Bonieck
- Departmento de Microbiologia-Universidade Federal de Minas Gerais, Av. Antonio Carlos 6627, Pampulha, Belo Horizonte, Minas Gerais CEP 31270901, Brazil
| | | | - Maria Aparecida Resende-Stoianoff
- Departmento de Microbiologia-Universidade Federal de Minas Gerais, Av. Antonio Carlos 6627, Pampulha, Belo Horizonte, Minas Gerais CEP 31270901, Brazil
| | - Alvaro Peix
- Instituto de Recursos Naturales y Agrobiología (IRNASA-CSIC), Cordel de Merinas 40-52, 37008 Salamanca, Spain
| | - Encarna Velázquez
- Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain
| | - Pedro F Mateos
- Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain
| | - Maria Rita Scotti
- Departmento de Botânica - Universidade Federal de Minas Gerais, Av. Antonio Carlos 6627, Pampulha, Belo Horizonte, Minas Gerais CEP 31270901, Brazil.
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11
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Marcos-García M, Menéndez E, García-Fraile P, Mateos PF, Rivas R. Mesorhizobium as a source of PHAs for bioplastic production. N Biotechnol 2016. [DOI: 10.1016/j.nbt.2015.10.038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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12
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Marcos-García M, Menéndez E, Mateos PF, Rivas R. Obtaining bacterial cellulose as alternative to plant cellulose. N Biotechnol 2016. [DOI: 10.1016/j.nbt.2015.10.075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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13
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Paço A, Brígido C, Alexandre A, Mateos PF, Oliveira S. The Symbiotic Performance of Chickpea Rhizobia Can Be Improved by Additional Copies of the clpB Chaperone Gene. PLoS One 2016; 11:e0148221. [PMID: 26845770 PMCID: PMC4741418 DOI: 10.1371/journal.pone.0148221] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Accepted: 01/14/2016] [Indexed: 12/03/2022] Open
Abstract
The ClpB chaperone is known to be involved in bacterial stress response. Moreover, recent studies suggest that this protein has also a role in the chickpea-rhizobia symbiosis. In order to improve both stress tolerance and symbiotic performance of a chickpea microsymbiont, the Mesorhizobium mediterraneum UPM-Ca36T strain was genetically transformed with pPHU231 containing an extra-copy of the clpB gene. To investigate if the clpB-transformed strain displays an improved stress tolerance, bacterial growth was evaluated under heat and acid stress conditions. In addition, the effect of the extra-copies of the clpB gene in the symbiotic performance was evaluated using plant growth assays (hydroponic and pot trials). The clpB-transformed strain is more tolerant to heat shock than the strain transformed with pPHU231, supporting the involvement of ClpB in rhizobia heat shock tolerance. Both plant growth assays showed that ClpB has an important role in chickpea-rhizobia symbiosis. The nodulation kinetics analysis showed a higher rate of nodule appearance with the clpB-transformed strain. This strain also induced a greater number of nodules and, more notably, its symbiotic effectiveness increased ~60% at pH5 and 83% at pH7, compared to the wild-type strain. Furthermore, a higher frequency of root hair curling was also observed in plants inoculated with the clpB-transformed strain, compared to the wild-type strain. The superior root hair curling induction, nodulation ability and symbiotic effectiveness of the clpB-transformed strain may be explained by an increased expression of symbiosis genes. Indeed, higher transcript levels of the nodulation genes nodA and nodC (~3 folds) were detected in the clpB-transformed strain. The improvement of rhizobia by addition of extra-copies of the clpB gene may be a promising strategy to obtain strains with enhanced stress tolerance and symbiotic effectiveness, thus contributing to their success as crop inoculants, particularly under environmental stresses. This is the first report on the successful improvement of a rhizobium with a chaperone gene.
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Affiliation(s)
- Ana Paço
- ICAAM–Instituto de Ciências Agrárias e Ambientais Mediterrânicas (Laboratório de Microbiologia do Solo), Universidade de Évora, Núcleo da Mitra, Ap. 94, 7002–554, Évora, Portugal
| | - Clarisse Brígido
- ICAAM–Instituto de Ciências Agrárias e Ambientais Mediterrânicas (Laboratório de Microbiologia do Solo), Universidade de Évora, Núcleo da Mitra, Ap. 94, 7002–554, Évora, Portugal
- IIFA–Instituto de Investigação e Formação Avançada, Universidade de Évora, Ap. 94, 7002–554, Évora, Portugal
| | - Ana Alexandre
- ICAAM–Instituto de Ciências Agrárias e Ambientais Mediterrânicas (Laboratório de Microbiologia do Solo), Universidade de Évora, Núcleo da Mitra, Ap. 94, 7002–554, Évora, Portugal
- IIFA–Instituto de Investigação e Formação Avançada, Universidade de Évora, Ap. 94, 7002–554, Évora, Portugal
| | - Pedro F. Mateos
- Departamento de Microbiología y Genética, Centro Hispano Luso de Investigaciones Agrarias, Universidad de Salamanca, 37007, Salamanca, Spain
| | - Solange Oliveira
- ICAAM–Instituto de Ciências Agrárias e Ambientais Mediterrânicas (Laboratório de Microbiologia do Solo), Universidade de Évora, Núcleo da Mitra, Ap. 94, 7002–554, Évora, Portugal
- * E-mail:
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14
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Menéndez E, Ramírez-Bahena MH, Carro L, Fernández-Pascual M, Peter Klenk H, Velázquez E, Mateos PF, Peix A, Rita Scotti M. Paenibacillus periandrae sp. nov., isolated from nodules of Periandra mediterranea. Int J Syst Evol Microbiol 2016; 66:1838-1843. [PMID: 26843192 DOI: 10.1099/ijsem.0.000953] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A bacterial strain designated PM10T was isolated from root nodules of Periandra mediterranea in Brazil. Phylogenetic analyses based on 16S rRNA gene sequences placed the isolate in the genus Paenibacillus with its closest relatives being Paenibacillus vulneris CCUG 53270T and Paenibacillus yunnanensis YN2T with 95.6 and 95.9% 16S rRNA gene sequence similarity, respectively. The isolate was a Gram-stain-variable, motile, sporulating rod that was catalase-negative and oxidase-positive. Caseinase was positive, amylase was weakly positive and gelatinase was negative. Growth was supported by many carbohydrates and organic acids as carbon sources. MK-7 was the only menaquinone detected and anteiso-C15 : 0 was the major fatty acid. Major polar lipids were diphosphatidylglycerol, phosphatidylmonomethylethanolamine, phosphatidylethanolamine, phosphatidylglycerol and two unidentified lipids. meso-Diaminopimelic acid was detected in the peptidoglycan. The DNA G+C content was 52.9 mol%. Phylogenetic, chemotaxonomic and phenotypic analyses showed that strain PM10T should be considered representative of a novel species of the genus Paenibacillus, for which the name Paenibacillus periandrae sp. nov. is proposed. The type strain is PM10T (=LMG 28691T=CECT 8827T).
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Affiliation(s)
- Esther Menéndez
- Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca,Spain
| | - Martha-Helena Ramírez-Bahena
- Instituto de Recursos Naturales y Agrobiología de Salamanca, Consejo Superior de Investigaciones Científicas (IRNASA-CSIC), Salamanca, Spain
- Unidad Asociada Grupo de Interacción Planta-Microorganismo Universidad de Salamanca-IRNASA-CSIC, Salamanca, Spain
| | - Lorena Carro
- School of Biology, Newcastle University, Newcastle upon Tyne, UK
| | | | - Hans Peter Klenk
- School of Biology, Newcastle University, Newcastle upon Tyne, UK
| | - Encarna Velázquez
- Unidad Asociada Grupo de Interacción Planta-Microorganismo Universidad de Salamanca-IRNASA-CSIC, Salamanca, Spain
- Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca,Spain
| | - Pedro F Mateos
- Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca,Spain
- Unidad Asociada Grupo de Interacción Planta-Microorganismo Universidad de Salamanca-IRNASA-CSIC, Salamanca, Spain
| | - Alvaro Peix
- Instituto de Recursos Naturales y Agrobiología de Salamanca, Consejo Superior de Investigaciones Científicas (IRNASA-CSIC), Salamanca, Spain
- Unidad Asociada Grupo de Interacción Planta-Microorganismo Universidad de Salamanca-IRNASA-CSIC, Salamanca, Spain
| | - Maria Rita Scotti
- Departamento de Botânica, Universidade Federal de Minas Gerais, Pampulha, Belo Horizonte, Brazil
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15
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Marcos-García M, Menéndez E, Cruz-González X, Velázquez E, Mateos PF, Rivas R. Erratum to: The high diversity of Lotus corniculatus endosymbionts in soils of northwest Spain. Symbiosis 2016. [DOI: 10.1007/s13199-016-0381-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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16
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Diez-Mendez A, Menéndez E, García-Fraile P, Celador-Lera L, Rivas R, Mateos PF. Rhizobium cellulosilyticum as a co-inoculant enhances Phaseolus vulgaris grain yield under greenhouse conditions. Symbiosis 2015. [DOI: 10.1007/s13199-015-0372-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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17
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Martínez-Hidalgo P, Ramírez-Bahena MH, Flores-Félix JD, Rivas R, Igual JM, Mateos PF, Martínez-Molina E, León-Barrios M, Peix Á, Velázquez E. Revision of the taxonomic status of type strains of Mesorhizobium loti and reclassification of strain USDA 3471T as the type strain of Mesorhizobium
erdmanii sp. nov. and ATCC 33669T as the type strain of Mesorhizobium
jarvisii sp. nov. Int J Syst Evol Microbiol 2015; 65:1703-1708. [DOI: 10.1099/ijs.0.000164] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The species Mesorhizobim loti was isolated from nodules of Lotus corniculatus and its type strain deposited in several collections. Some of these type strains, such as those deposited in the USDA and ATCC collections before 1990, are not coincident with the original strain, NZP 2213T, deposited in the NZP culture collection. The analysis of the 16S rRNA gene showed that strains USDA 3471T and ATCC 33669T formed independent branches from that occupied by
Mesorhizobium loti
NZP 2213T and related to those occupied by
Mesorhizobium opportunistum
WSM2075T and
Mesorhizobium huakuii
IFO 15243T, respectively, with 99.9 % similarity in both cases. However, the analysis of concatenated recA, atpD and glnII genes with similarities lower than 96, 98 and 94 %, respectively, between strains USDA 3471T and
M. opportunistum
WSM2075T and between strains ATCC 33669T and
M. huakuii
IFO 15243T, indicated that the strains USDA 3471T and ATCC 33669T represent different species of the genus
Mesorhizobium
. These results were confirmed by DNA–DNA hybridization experiments and phenotypic characterization. Therefore, the two strains were reclassified as representatives of the two species Mesorhizobium erdmanii sp. nov. (type strain USDA 3471T = CECT 8631T = LMG 17826t2T) and Mesorhizobium jarvisii sp. nov. (type strain ATCC 33669T = CECT 8632T = LMG 28313T).
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Affiliation(s)
| | - Martha Helena Ramírez-Bahena
- IRNASA-CSIC, Salamanca, Spain
- Unidad Asociada Universidad de Salamanca-CSIC ‘Interacciones Planta-Microorganismo, Salamanca, Spain
| | | | - Raúl Rivas
- Departamento de Microbiología y Genética, Universidad de Salamanca., Salamanca, Spain
- Unidad Asociada Universidad de Salamanca-CSIC ‘Interacciones Planta-Microorganismo, Salamanca, Spain
| | - José M. Igual
- IRNASA-CSIC, Salamanca, Spain
- Unidad Asociada Universidad de Salamanca-CSIC ‘Interacciones Planta-Microorganismo, Salamanca, Spain
| | - Pedro F. Mateos
- Departamento de Microbiología y Genética, Universidad de Salamanca., Salamanca, Spain
- Unidad Asociada Universidad de Salamanca-CSIC ‘Interacciones Planta-Microorganismo, Salamanca, Spain
| | - Eustoquio Martínez-Molina
- Departamento de Microbiología y Genética, Universidad de Salamanca., Salamanca, Spain
- Unidad Asociada Universidad de Salamanca-CSIC ‘Interacciones Planta-Microorganismo, Salamanca, Spain
| | - Milagros León-Barrios
- Departamento de Bioquímica, Microbiología, Biología Celular y Genética, Universidad de La Laguna, Tenerife, Spain
| | - Álvaro Peix
- IRNASA-CSIC, Salamanca, Spain
- Unidad Asociada Universidad de Salamanca-CSIC ‘Interacciones Planta-Microorganismo, Salamanca, Spain
| | - Encarna Velázquez
- Departamento de Microbiología y Genética, Universidad de Salamanca., Salamanca, Spain
- Unidad Asociada Universidad de Salamanca-CSIC ‘Interacciones Planta-Microorganismo, Salamanca, Spain
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18
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Menéndez E, Ramírez-Bahena MH, Fabryová A, Igual JM, Benada O, Mateos PF, Peix A, Kolařík M, García-Fraile P. Pseudomonas coleopterorum sp. nov., a cellulase-producing bacterium isolated from the bark beetle Hylesinus fraxini. Int J Syst Evol Microbiol 2015; 65:2852-2858. [PMID: 25999590 DOI: 10.1099/ijs.0.000344] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
We isolated a strain coded Esc2Am(T) during a study focused on the microbial diversity of adult specimens of the bark beetle Hylesinus fraxini. Its 16S rRNA gene sequence had 99.4% similarity with respect to its closest relative, Pseudomonas rhizosphaerae IH5(T). The analysis of partial sequences of the housekeeping genes rpoB, rpoD and gyrB confirmed that strain Esc2Am(T) formed a cluster with P. rhizosphaerae IH5(T) clearly separated from the remaining species of the genus Pseudomonas. Strain Esc2Am(T) had polar flagella and could grow at temperatures from 4 °C to 30 °C. The respiratory quinone was Q9 and the main fatty acids were C16 : 0, C18 : 1ω7c and/or C18 : 1ω6c in summed feature 8 and C16 : 1ω7c and/or C16 : 1ω6c in summed feature 3. DNA-DNA hybridization results showed 51% relatedness with respect to P. rhizosphaerae IH5(T). Oxidase, catalase and urease-positive, the arginine dihydrolase system was present but nitrate reduction and β-galactosidase production were negative. Aesculin hydrolysis was positive. Based on the results from the genotypic, phenotypic and chemotaxonomic analyses, we propose the classification of strain Esc2Am(T) as representing a novel species of the genus Pseudomonas, for which we propose the name Pseudomonas coleopterorum sp. nov. The type strain is Esc2Am(T) ( = LMG 28558(T)= CECT 8695(T)).
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Affiliation(s)
- Esther Menéndez
- Microbiology and Genetics Department, University of Salamanca, Spain
| | | | - Anna Fabryová
- Institute of Microbiology, Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - José M Igual
- Institute of Natural Resources and Agrobiology. IRNASA-CSIC, Salamanca, Spain
| | - Oldrich Benada
- Institute of Microbiology, Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - Pedro F Mateos
- Microbiology and Genetics Department, University of Salamanca, Spain
| | - Alvaro Peix
- Institute of Natural Resources and Agrobiology. IRNASA-CSIC, Salamanca, Spain
| | - Miroslav Kolařík
- Institute of Microbiology, Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - Paula García-Fraile
- Institute of Microbiology, Academy of Sciences of the Czech Republic, Prague, Czech Republic
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19
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Flores-Félix JD, Silva LR, Rivera LP, Marcos-García M, García-Fraile P, Martínez-Molina E, Mateos PF, Velázquez E, Andrade P, Rivas R. Plants probiotics as a tool to produce highly functional fruits: the case of phyllobacterium and vitamin C in strawberries. PLoS One 2015; 10:e0122281. [PMID: 25874563 PMCID: PMC4398434 DOI: 10.1371/journal.pone.0122281] [Citation(s) in RCA: 84] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2014] [Accepted: 02/13/2015] [Indexed: 01/20/2023] Open
Abstract
The increasing interest in the preservation of the environment and the health of consumers is changing production methods and food consumption habits. Functional foods are increasingly demanded by consumers because they contain bioactive compounds involved in health protection. In this sense biofertilization using plant probiotics is a reliable alternative to the use of chemical fertilizers, but there are few studies about the effects of plant probiotics on the yield of functional fruits and, especially, on the content of bioactive compounds. In the present work we reported that a strain of genus Phyllobacterium able to produce biofilms and to colonize strawberry roots is able to increase the yield and quality of strawberry plants. In addition, the fruits from plants inoculated with this strain have significantly higher content in vitamin C, one of the most interesting bioactive compounds in strawberries. Therefore the use of selected plant probiotics benefits the environment and human health without agronomical losses, allowing the production of highly functional foods.
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Affiliation(s)
| | - Luis R. Silva
- REQUIMTE/, Laboratório de Farmacognosia, Departamento de Química, Faculdade de Farmácia, Universidade do Porto, Porto, Portugal
| | - Lina P. Rivera
- Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain
- Centro Hispano Luso de Investigaciones Agrarias (CIALE), Universidad de Salamanca, Salamanca, Spain
| | - Marta Marcos-García
- Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain
| | - Paula García-Fraile
- Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain
| | - Eustoquio Martínez-Molina
- Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain
- Centro Hispano Luso de Investigaciones Agrarias (CIALE), Universidad de Salamanca, Salamanca, Spain
- Unidad Asociada Universidad de Salamanca-CSIC (IRNASA), Salamanca, Spain
| | - Pedro F. Mateos
- Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain
- Centro Hispano Luso de Investigaciones Agrarias (CIALE), Universidad de Salamanca, Salamanca, Spain
- Unidad Asociada Universidad de Salamanca-CSIC (IRNASA), Salamanca, Spain
| | - Encarna Velázquez
- Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain
- Unidad Asociada Universidad de Salamanca-CSIC (IRNASA), Salamanca, Spain
| | - Paula Andrade
- REQUIMTE/, Laboratório de Farmacognosia, Departamento de Química, Faculdade de Farmácia, Universidade do Porto, Porto, Portugal
| | - Raúl Rivas
- Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain
- Unidad Asociada Universidad de Salamanca-CSIC (IRNASA), Salamanca, Spain
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20
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Peix A, Ramírez-Bahena MH, Flores-Félix JD, Alonso de la Vega P, Rivas R, Mateos PF, Igual JM, Martínez-Molina E, Trujillo ME, Velázquez E. Revision of the taxonomic status of the species Rhizobium lupini and reclassification as Bradyrhizobium lupini comb. nov. Int J Syst Evol Microbiol 2015; 65:1213-1219. [DOI: 10.1099/ijs.0.000082] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The species
Rhizobium lupini
was isolated from Lupinus nodules and included in the Approved Lists of Bacterial Names in 1980. Nevertheless, on the basis of the analysis of the type strain of this species available in DSMZ, DSM 30140T, whose 16S rRNA gene was identical to that of the type strain of
Bradyrhizobium japonicum
,
R. lupini
was considered a later synonym of this species. In this study we confirmed that the strain DSM 30140T belongs to the species
B. japonicum
, but also that it cannot be the original strain of
R. lupini
because this species effectively nodulated Lupinus whereas strain DSM 30140T was able to nodulate soybean but not Lupinus. Since the original type strain of
R. lupini
was deposited into the USDA collection by L. W. Erdman under the accession number USDA 3051T we analysed the taxonomic status of this strain showing that although it belongs to the genus
Bradyrhizobium
instead of genus
Rhizobium
, it is phylogenetically distant from
B. japonicum
and closely related to
Bradyrhizobium canariense
. The type strains
R. lupini
USDA 3051T and
B. canariense
BTA-1T share 16S rRNA, recA and glnII gene sequences with similarities of 99.8 %, 96.5 % and 97.1 %, respectively. They presented a DNA–DNA hybridization value of 36 % and also differed in phenotypic characteristics and slightly in the proportions of some fatty acids. Therefore we propose the reclassification of the species
Rhizobium lupini
as Bradyrhizobium lupini comb. nov. The type strain is USDA 3051T ( = CECT 8630T = LMG 28514T).
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Affiliation(s)
- Alvaro Peix
- Unidad Asociada Universidad de Salamanca-CSIC ‘Interacción Planta-Microorganismo’, Salamanca, Spain
- Instituto de Recursos Naturales y Agrobiología de Salamanca, Consejo Superior de Investigaciones Científicas (IRNASA-CSIC), Salamanca, Spain
| | - Martha Helena Ramírez-Bahena
- Unidad Asociada Universidad de Salamanca-CSIC ‘Interacción Planta-Microorganismo’, Salamanca, Spain
- Instituto de Recursos Naturales y Agrobiología de Salamanca, Consejo Superior de Investigaciones Científicas (IRNASA-CSIC), Salamanca, Spain
| | - José David Flores-Félix
- Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain
- Unidad Asociada Universidad de Salamanca-CSIC ‘Interacción Planta-Microorganismo’, Salamanca, Spain
| | | | - Raúl Rivas
- Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain
- Unidad Asociada Universidad de Salamanca-CSIC ‘Interacción Planta-Microorganismo’, Salamanca, Spain
| | - Pedro F. Mateos
- Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain
- Unidad Asociada Universidad de Salamanca-CSIC ‘Interacción Planta-Microorganismo’, Salamanca, Spain
| | - José M. Igual
- Unidad Asociada Universidad de Salamanca-CSIC ‘Interacción Planta-Microorganismo’, Salamanca, Spain
- Instituto de Recursos Naturales y Agrobiología de Salamanca, Consejo Superior de Investigaciones Científicas (IRNASA-CSIC), Salamanca, Spain
| | - Eustoquio Martínez-Molina
- Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain
- Unidad Asociada Universidad de Salamanca-CSIC ‘Interacción Planta-Microorganismo’, Salamanca, Spain
| | - Martha E. Trujillo
- Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain
- Unidad Asociada Universidad de Salamanca-CSIC ‘Interacción Planta-Microorganismo’, Salamanca, Spain
| | - Encarna Velázquez
- Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain
- Unidad Asociada Universidad de Salamanca-CSIC ‘Interacción Planta-Microorganismo’, Salamanca, Spain
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Brígido C, Robledo M, Menéndez E, Mateos PF, Oliveira S. A ClpB chaperone knockout mutant of Mesorhizobium ciceri shows a delay in the root nodulation of chickpea plants. Mol Plant Microbe Interact 2012; 25:1594-1604. [PMID: 23134119 DOI: 10.1094/mpmi-05-12-0140-r] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Several molecular chaperones are known to be involved in bacteria stress response. To investigate the role of chaperone ClpB in rhizobia stress tolerance as well as in the rhizobia-plant symbiosis process, the clpB gene from a chickpea microsymbiont, strain Mesorhizobium ciceri LMS-1, was identified and a knockout mutant was obtained. The ClpB knockout mutant was tested to several abiotic stresses, showing that it was unable to grow after a heat shock and it was more sensitive to acid shock than the wild-type strain. A plant-growth assay performed to evaluate the symbiotic performance of the clpB mutant showed a higher proportion of ineffective root nodules obtained with the mutant than with the wild-type strain. Nodulation kinetics analysis showed a 6- to 8-day delay in nodule appearance in plants inoculated with the ΔclpB mutant. Analysis of nodC gene expression showed lower levels of transcript in the ΔclpB mutant strain. Analysis of histological sections of nodules formed by the clpB mutant showed that most of the nodules presented a low number of bacteroids. No differences in the root infection abilities of green fluorescent protein-tagged clpB mutant and wild-type strains were detected. To our knowledge, this is the first study that presents evidence of the involvement of the chaperone ClpB from rhizobia in the symbiotic nodulation process.
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Fonseca MB, Peix A, de Faria SM, Mateos PF, Rivera LP, Simões-Araujo JL, França MGC, dos Santos Isaias RM, Cruz C, Velázquez E, Scotti MR, Sprent JI, James EK. Nodulation in Dimorphandra wilsonii Rizz. (Caesalpinioideae), a threatened species native to the Brazilian Cerrado. PLoS One 2012; 7:e49520. [PMID: 23185349 PMCID: PMC3501520 DOI: 10.1371/journal.pone.0049520] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2012] [Accepted: 10/09/2012] [Indexed: 11/19/2022] Open
Abstract
The threatened caesalpinioid legume Dimorphandra wilsonii, which is native to the Cerrado biome in Brazil, was examined for its nodulation and N(2)-fixing ability, and was compared with another, less-threatened species, D. jorgei. Nodulation and potential N(2) fixation was shown on seedlings that had been inoculated singly with five bradyrhizobial isolates from mature D. wilsonii nodules. The infection of D. wilsonii by two of these strains (Dw10.1, Dw12.5) was followed in detail using light and transmission electron microscopy, and was compared with that of D. jorgei by Bradyrhizobium strain SEMIA6099. The roots of D. wilsonii were infected via small transient root hairs at 42 d after inoculation (dai), and nodules were sufficiently mature at 63 dai to express nitrogenase protein. Similar infection and nodule developmental processes were observed in D. jorgei. The bacteroids in mature Dimorphandra nodules were enclosed in plant cell wall material containing a homogalacturonan (pectic) epitope that was recognized by the monoclonal antibody JIM5. Analysis of sequences of their rrs (16S rRNA) genes and their ITS regions showed that the five D. wilsonii strains, although related to SEMIA6099, may constitute five undescribed species of genus Bradyrhizobium, whilst their nodD and nifH gene sequences showed that they formed clearly separated branches from other rhizobial strains. This is the first study to describe in full the N(2)-fixing symbiotic interaction between defined rhizobial strains and legumes in the sub-family Caesalpinioideae. This information will hopefully assist in the conservation of the threatened species D. wilsonii.
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Affiliation(s)
- Márcia Bacelar Fonseca
- Depto de Botânica, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Alvaro Peix
- Instituto de Recursos Naturales y Agrobiología, IRNASA-CSIC, Unidad Asociada Universidad de Salamanca-CSIC ‘Interacción Planta-Microorganismo’, Salamanca, Spain
| | | | - Pedro F. Mateos
- Departamento de Microbiología y Genética-CIALE, Universidad de Salamanca, Unidad Asociada Universidad de Salamanca-CSIC ‘Interacción Planta-Microorganismo’, Salamanca, Spain
| | - Lina P. Rivera
- Departamento de Microbiología y Genética-CIALE, Universidad de Salamanca, Unidad Asociada Universidad de Salamanca-CSIC ‘Interacción Planta-Microorganismo’, Salamanca, Spain
| | | | | | | | - Cristina Cruz
- Universidade de Lisboa, Faculdade de Ciências, Centro de Biologia Ambiental (CBA), Lisboa, Portugal
| | - Encarna Velázquez
- Departamento de Microbiología y Genética-CIALE, Universidad de Salamanca, Unidad Asociada Universidad de Salamanca-CSIC ‘Interacción Planta-Microorganismo’, Salamanca, Spain
| | - Maria Rita Scotti
- Depto de Botânica, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Janet I. Sprent
- Division of Plant Sciences, University of Dundee at James Hutton Institute, Dundee, United Kingdom
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Robledo M, Rivera L, Jiménez-Zurdo JI, Rivas R, Dazzo F, Velázquez E, Martínez-Molina E, Hirsch AM, Mateos PF. Role of Rhizobium endoglucanase CelC2 in cellulose biosynthesis and biofilm formation on plant roots and abiotic surfaces. Microb Cell Fact 2012; 11:125. [PMID: 22970813 PMCID: PMC3520766 DOI: 10.1186/1475-2859-11-125] [Citation(s) in RCA: 77] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2012] [Accepted: 09/06/2012] [Indexed: 02/02/2023] Open
Abstract
Background The synthesis of cellulose is among the most important but poorly understood biochemical processes, especially in bacteria, due to its complexity and high degree of regulation. In this study, we analyzed both the production of cellulose by all known members of the Rhizobiaceae and the diversity of Rhizobium celABC operon predicted to be involved in cellulose biosynthesis. We also investigated the involvement in cellulose production and biofilm formation of celC gene encoding an endoglucanase (CelC2) that is required for canonical symbiotic root hair infection by Rhizobium leguminosarum bv. trifolii. Results ANU843 celC mutants lacking (ANU843ΔC2) or overproducing cellulase (ANU843C2+) produced greatly increased or reduced amounts of external cellulose micro fibrils, respectively. Calcofluor-stained cellulose micro fibrils were considerably longer when formed by ANU843ΔC2 bacteria rather than by the wild-type strain, in correlation with a significant increase in their flocculation in batch culture. In contrast, neither calcofluor-stained extracellular micro fibrils nor flocculation was detectable in ANU843C2+ cells. To clarify the role of cellulose synthesis in Rhizobium cell aggregation and attachment, we analyzed the ability of these mutants to produce biofilms on different surfaces. Alteration of wild-type CelC2 levels resulted in a reduced ability of bacteria to form biofilms both in abiotic surfaces and in planta. Conclusions Our results support a key role of the CelC2 cellulase in cellulose biosynthesis by modulating the length of the cellulose fibrils that mediate firm adhesion among Rhizobium bacteria leading to biofilm formation. Rhizobium cellulose is an essential component of the biofilm polysaccharidic matrix architecture and either an excess or a defect of this “building material” seem to collapse the biofilm structure. These results position cellulose hydrolytic enzymes as excellent anti-biofilm candidates.
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Affiliation(s)
- M Robledo
- Departamento de Microbiología y Genética and CIALE, Universidad de Salamanca, Salamanca, Spain
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García-Fraile P, Carro L, Robledo M, Ramírez-Bahena MH, Flores-Félix JD, Fernández MT, Mateos PF, Rivas R, Igual JM, Martínez-Molina E, Peix Á, Velázquez E. Rhizobium promotes non-legumes growth and quality in several production steps: towards a biofertilization of edible raw vegetables healthy for humans. PLoS One 2012; 7:e38122. [PMID: 22675441 PMCID: PMC3364997 DOI: 10.1371/journal.pone.0038122] [Citation(s) in RCA: 126] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2011] [Accepted: 04/30/2012] [Indexed: 11/18/2022] Open
Abstract
The biofertilization of crops with plant-growth-promoting microorganisms is currently considered as a healthy alternative to chemical fertilization. However, only microorganisms safe for humans can be used as biofertilizers, particularly in vegetables that are raw consumed, in order to avoid sanitary problems derived from the presence of pathogenic bacteria in the final products. In the present work we showed that Rhizobium strains colonize the roots of tomato and pepper plants promoting their growth in different production stages increasing yield and quality of seedlings and fruits. Our results confirmed those obtained in cereals and alimentary oil producing plants extending the number of non-legumes susceptible to be biofertilized with rhizobia to those whose fruits are raw consumed. This is a relevant conclusion since safety of rhizobia for human health has been demonstrated after several decades of legume inoculation ensuring that they are optimal bacteria for biofertilization.
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Affiliation(s)
- Paula García-Fraile
- Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain
| | - Lorena Carro
- Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain
| | - Marta Robledo
- Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain
- Centro Hispano-Luso de Investigaciones Agrarias, Salamanca, Spain
| | - Martha-Helena Ramírez-Bahena
- Instituto de Recursos Naturales y Agrobiología, Consejo Superior de Investigaciones Científicas, Salamanca, Spain
- Unidad Asociada Grupo de Interacción planta-microorganismo, Universidad de Salamanca–Consejo Superior de Investigaciones Científicas, Salamanca, Spain
| | | | | | - Pedro F. Mateos
- Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain
- Centro Hispano-Luso de Investigaciones Agrarias, Salamanca, Spain
- Unidad Asociada Grupo de Interacción planta-microorganismo, Universidad de Salamanca–Consejo Superior de Investigaciones Científicas, Salamanca, Spain
| | - Raúl Rivas
- Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain
- Unidad Asociada Grupo de Interacción planta-microorganismo, Universidad de Salamanca–Consejo Superior de Investigaciones Científicas, Salamanca, Spain
| | - José Mariano Igual
- Instituto de Recursos Naturales y Agrobiología, Consejo Superior de Investigaciones Científicas, Salamanca, Spain
- Unidad Asociada Grupo de Interacción planta-microorganismo, Universidad de Salamanca–Consejo Superior de Investigaciones Científicas, Salamanca, Spain
| | - Eustoquio Martínez-Molina
- Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain
- Centro Hispano-Luso de Investigaciones Agrarias, Salamanca, Spain
- Unidad Asociada Grupo de Interacción planta-microorganismo, Universidad de Salamanca–Consejo Superior de Investigaciones Científicas, Salamanca, Spain
| | - Álvaro Peix
- Instituto de Recursos Naturales y Agrobiología, Consejo Superior de Investigaciones Científicas, Salamanca, Spain
- Unidad Asociada Grupo de Interacción planta-microorganismo, Universidad de Salamanca–Consejo Superior de Investigaciones Científicas, Salamanca, Spain
| | - Encarna Velázquez
- Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain
- Unidad Asociada Grupo de Interacción planta-microorganismo, Universidad de Salamanca–Consejo Superior de Investigaciones Científicas, Salamanca, Spain
- * E-mail:
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25
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Robledo M, Velázquez E, Ramírez-Bahena MH, García-Fraile P, Pérez-Alonso A, Rivas R, Martínez-Molina E, Mateos PF. The celC gene, a new phylogenetic marker useful for taxonomic studies in Rhizobium. Syst Appl Microbiol 2011; 34:393-9. [DOI: 10.1016/j.syapm.2011.01.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2010] [Revised: 01/15/2011] [Accepted: 01/17/2011] [Indexed: 11/17/2022]
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Robledo M, Jiménez-Zurdo JI, Soto MJ, Velázquez E, Dazzo F, Martínez-Molina E, Mateos PF. Development of functional symbiotic white clover root hairs and nodules requires tightly regulated production of rhizobial cellulase CelC2. Mol Plant Microbe Interact 2011; 24:798-807. [PMID: 21405987 DOI: 10.1094/mpmi-10-10-0249] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The establishment of rhizobia as nitrogen-fixing endosymbionts within legume root nodules requires the disruption of the plant cell wall to breach the host barrier at strategic infection sites in the root hair tip and at points of bacterial release from infection threads (IT) within the root cortex. We previously found that Rhizobium leguminosarum bv. trifolii uses its chromosomally encoded CelC2 cellulase to erode the noncrystalline wall at the apex of root hairs, thereby creating the primary portal of its entry into white clover roots. Here, we show that a recombinant derivative of R. leguminosarum bv. trifolii ANU843 that constitutively overproduces the CelC2 enzyme has increased competitiveness in occupying aberrant nodule-like root structures on clover that are inefficient in nitrogen fixation. This aberrant symbiotic phenotype involves an extensive uncontrolled degradation of the host cell walls restricted to the expected infection sites at tips of deformed root hairs and significantly enlarged infection droplets at termini of wider IT within the nodule infection zone. Furthermore, signs of elevated plant host defense as indicated by reactive oxygen species production in root tissues were more evident during infection by the recombinant strain than its wild-type parent. Our data further support the role of the rhizobial CelC2 cell wall-degrading enzyme in primary infection, and show evidence of its importance in secondary symbiotic infection and tight regulation of its production to establish an effective nitrogen-fixing root nodule symbiosis.
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Affiliation(s)
- Marta Robledo
- Departamento de Microbiologia, Universidad de Salamanca, Salamanca, Spain
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27
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Ferreira L, Sánchez-Juanes F, García-Fraile P, Rivas R, Mateos PF, Martínez-Molina E, González-Buitrago JM, Velázquez E. MALDI-TOF mass spectrometry is a fast and reliable platform for identification and ecological studies of species from family Rhizobiaceae. PLoS One 2011; 6:e20223. [PMID: 21655291 PMCID: PMC3105015 DOI: 10.1371/journal.pone.0020223] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2011] [Accepted: 04/21/2011] [Indexed: 11/19/2022] Open
Abstract
Family Rhizobiaceae includes fast growing bacteria currently arranged into three genera, Rhizobium, Ensifer and Shinella, that contain pathogenic, symbiotic and saprophytic species. The identification of these species is not possible on the basis of physiological or biochemical traits and should be based on sequencing of several genes. Therefore alternative methods are necessary for rapid and reliable identification of members from family Rhizobiaceae. In this work we evaluated the suitability of Matrix-Assisted Laser Desorption Ionization-Time-of-Flight Mass Spectrometry (MALDI-TOF MS) for this purpose. Firstly, we evaluated the capability of this methodology to differentiate among species of family Rhizobiaceae including those closely related and then we extended the database of MALDI Biotyper 2.0 including the type strains of 56 species from genera Rhizobium, Ensifer and Shinella. Secondly, we evaluated the identification potential of this methodology by using several strains isolated from different sources previously identified on the basis of their rrs, recA and atpD gene sequences. The 100% of these strains were correctly identified showing that MALDI-TOF MS is an excellent tool for identification of fast growing rhizobia applicable to large populations of isolates in ecological and taxonomic studies.
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Affiliation(s)
- Laura Ferreira
- Unidad de Investigación, Hospital Universitario de Salamanca, Salamanca, Spain
| | | | - Paula García-Fraile
- Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain
| | - Raúl Rivas
- Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain
| | - Pedro F. Mateos
- Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain
| | | | - José Manuel González-Buitrago
- Unidad de Investigación, Hospital Universitario de Salamanca, Salamanca, Spain
- Departamento de Bioquímica y Biología Molecular, Universidad de Salamanca, Salamanca, Spain
| | - Encarna Velázquez
- Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain
- * E-mail:
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28
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Velázquez E, Palomo JL, Rivas R, Guerra H, Peix A, Trujillo ME, García-Benavides P, Mateos PF, Wabiko H, Martínez-Molina E. Analysis of core genes supports the reclassification of strains Agrobacterium radiobacter K84 and Agrobacterium tumefaciens AKE10 into the species Rhizobium rhizogenes. Syst Appl Microbiol 2010; 33:247-51. [PMID: 20627641 DOI: 10.1016/j.syapm.2010.04.004] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2009] [Revised: 04/17/2010] [Accepted: 04/20/2010] [Indexed: 11/18/2022]
Abstract
Some strains of the former genus Agrobacterium have high biotechnological interest and are currently misclassified. Consequently, in this study, the taxonomic status of the non-pathogenic strain Agrobacterium radiobacter K84, used in biological control, and the tumourigenic strain Agrobacterium tumefaciens AKE10, able to regenerate tobacco transgenic plants, was revised. The phylogenetic analysis of the chromosomal genes rrs, atpD and recA showed that they should be reclassified into Rhizobium rhizogenes. The analysis of virulence genes located in the Ti plasmid (pTi) outside T-DNA showed a common phylogenetic origin among strains AKE10, R. rhizogenes 163C and A. tumefaciens (currently R. radiobacter) C58. However, the genes located inside the T-DNA, mainly the 6b gene, of strain AKE10 were phylogenetically close to those of strain 163C but divergent from those of strain C58. Furthermore, the T-DNA of tumourigenic strains from R. rhizogenes conferred on them the ability to regenerate tumour tissue resembling fasciation in tobacco plants. These results showed the existence of a highly mosaic genetic organization in tumourigenic strains of the genus Rhizobium and provided evidence of the involvement of T-DNA from tumourigenic strains of R. rhizogenes in fasciation of Nicotiana leaves. The data further suggested that pathogenic strains of Rhizobium could be good models to analyse bacterial evolution.
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Affiliation(s)
- Encarna Velázquez
- Departamento de Microbiología y Genética, Edificio Departamental de Biología, Universidad de Salamanca, Campus Miguel de Unamuno, 37007 Salamanca, Spain.
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Velázquez E, Valverde A, Rivas R, Gomis V, Peix Á, Gantois I, Igual JM, León-Barrios M, Willems A, Mateos PF, Martínez-Molina E. Strains nodulating Lupinus albus on different continents belong to several new chromosomal and symbiotic lineages within Bradyrhizobium. Antonie van Leeuwenhoek 2010; 97:363-76. [DOI: 10.1007/s10482-010-9415-7] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2009] [Accepted: 01/12/2010] [Indexed: 11/25/2022]
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Ramírez-Bahena MH, Velázquez E, Fernández-Santos F, Peix A, Martínez-Molina E, Mateos PF. Phenotypic, genotypic, and symbiotic diversities in strains nodulating clover in different soils in Spain. Can J Microbiol 2009; 55:1207-16. [PMID: 19935893 DOI: 10.1139/w09-074] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Trifolium species are the most common legumes present in wild Spanish soils; however, there are no studies to date on the diversity of rhizobia nodulating clover in Spain. Twenty strains from different Spanish soils with acidic, neutral, and basic pH were selected to study their genotypic, phenotypic, and symbiotic features. The results showed that the isolates were genotypically diverse, displaying 12 different DNA fingerprint patterns and also 14 different plasmid profiles. Although they have 16S rRNA gene sequences that are nearly identical to that of the type strain of Rhizobium leguminosarum, their recA and atpD gene sequences were phylogenetically divergent from those of R. leguminosarum reference strains, and phenotypic divergence as well as different host ranges were also found. Although most of them nodulated both Trifolium and Phaseolus, only 5 strains were also able to nodulate Pisum. The results of the effectiveness analysis showed a high variability in the symbiotic characteristics of our strains and suggested that Pisum is the more restrictive host of this group. Interestingly, some of the Trifolium isolates showed an ability to promote growth of Pisum in the absence of nodulation.
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Álvarez-Martínez ER, Valverde Á, Ramírez-Bahena MH, García-Fraile P, Tejedor C, Mateos PF, Santillana N, Zúñiga D, Peix A, Velázquez E. The analysis of core and symbiotic genes of rhizobia nodulating Vicia from different continents reveals their common phylogenetic origin and suggests the distribution of Rhizobium leguminosarum strains together with Vicia seeds. Arch Microbiol 2009; 191:659-68. [DOI: 10.1007/s00203-009-0495-6] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2009] [Revised: 05/31/2009] [Accepted: 07/02/2009] [Indexed: 11/30/2022]
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Ramírez-Bahena MH, Peix A, Rivas R, Camacho M, Rodríguez-Navarro DN, Mateos PF, Martínez-Molina E, Willems A, Velázquez E. Bradyrhizobium pachyrhizi sp. nov. and Bradyrhizobium jicamae sp. nov., isolated from effective nodules of Pachyrhizus erosus. Int J Syst Evol Microbiol 2009; 59:1929-34. [PMID: 19567584 DOI: 10.1099/ijs.0.006320-0] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Several strains isolated from the legume Pachyrhizus erosus were characterized on the basis of diverse genetic, phenotypic and symbiotic approaches. These novel strains formed two groups closely related to Bradyrhizobium elkanii according to their 16S rRNA gene sequences. Strains PAC48T and PAC68T, designated as the type strains of these two groups, presented 99.8 and 99.1% similarity, respectively, in their 16S rRNA gene sequences with respect to B. elkanii USDA 76T. In spite of these high similarity values, the analysis of additional phylogenetic markers such as atpD and glnII genes and the 16S-23S intergenic spacer (ITS) showed that strains PAC48T and PAC68T represented two separate novel species of the genus Bradyrhizobium with B. elkanii as their closest relative. Phenotypic differences among the novel strains isolated from Pachyrhizus and B. elkanii were found regarding the assimilation of carbon sources and antibiotic resistance. All these differences were congruent with DNA-DNA hybridization analysis which revealed 21% genetic relatedness between strains PAC48T and PAC68T and 46% and 25%, respectively, between these strains and B. elkanii LMG 6134T. The nodD and nifH genes of strains PAC48T and PAC68T were phylogenetically divergent from those of bradyrhizobia species that nodulate soybean. Soybean was not nodulated by the novel Pachyrhizus isolates. Based on the genotypic and phenotypic data obtained in this study, the new strains represent two novel species for which the names Bradyrhizobium pachyrhizi sp. nov. (type strain PAC48T=LMG 24246T=CECT 7396T) and Bradyrhizobium jicamae sp. nov. (type strain PAC68T=LMG 24556T=CECT 7395T) are proposed.
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Peix A, Lang E, Verbarg S, Spröer C, Rivas R, Santa-Regina I, Mateos PF, Martínez-Molina E, Rodríguez-Barrueco C, Velázquez E. Acinetobacter strains IH9 and OCI1, two rhizospheric phosphate solubilizing isolates able to promote plant growth, constitute a new genomovar of Acinetobacter calcoaceticus. Syst Appl Microbiol 2009; 32:334-41. [PMID: 19467815 DOI: 10.1016/j.syapm.2009.03.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/12/2009] [Indexed: 11/27/2022]
Abstract
During a screening of phosphate solubilizing bacteria (PSB) in agricultural soils, two strains, IH9 and OCI1, were isolated from the rhizosphere of grasses in Spain, and they showed a high ability to solubilize phosphate in vitro. Inoculation experiments in chickpea and barley were conducted with both strains and the results demonstrated their ability to promote plant growth. The 16S rRNA gene sequences of these strains were nearly identical to each other and to those of Acinetobacter calcoaceticus DSM 30006(T), as well as the strain CIP 70.29 representing genomospecies 3. Their phenotypic characteristics also coincided with those of strains forming the A. calcoaceticus-baumannii complex. They differed from A. calcoaceticus in the utilization of l-tartrate as a carbon source and from genomospecies 3 in the use of d-asparagine as a carbon source. The 16S-23S intergenic spacer (ITS) sequences of the two isolates showed nearly 98% identities to those of A. calcoaceticus, confirming that they belong to this phylogenetic group. However, the isolates appeared as a separate branch from the A. calcoaceticus sequences, indicating their molecular separation from other A. calcoaceticus strains. The analysis of three housekeeping genes, recA, rpoD and gyrB, confirmed that IH9 and OCI1 form a distinct lineage within A. calcoaceticus. These results were congruent with those from DNA-DNA hybridization, indicating that strains IH9 and OCI1 constitute a new genomovar for which we propose the name A. calcoaceticus genomovar rhizosphaerae.
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Affiliation(s)
- Alvaro Peix
- Instituto de Recursos Naturales y Agrobiología, IRNASA-CSIC, Salamanca, Spain
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Ramírez-Bahena MH, García-Fraile P, Peix A, Valverde A, Rivas R, Igual JM, Mateos PF, Martínez-Molina E, Velázquez E. Revision of the taxonomic status of the species Rhizobium leguminosarum (Frank 1879) Frank 1889AL, Rhizobium phaseoli Dangeard 1926AL and Rhizobium trifolii Dangeard 1926AL. R. trifolii is a later synonym of R. leguminosarum. Reclassification of the strain R. leguminosarum DSM 30132 (=NCIMB 11478) as Rhizobium pisi sp. nov. Int J Syst Evol Microbiol 2009; 58:2484-90. [PMID: 18984681 DOI: 10.1099/ijs.0.65621-0] [Citation(s) in RCA: 101] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The taxonomic status of the species Rhizobium leguminosarum, Rhizobium trifolii and Rhizobium phaseoli was analysed in this study on the basis of their molecular and phenotypic characteristics. According to the results, the type strain R. phaseoli ATCC 14482(T) does not belong to any of the already described species of the genus Rhizobium and it should therefore be considered as a different species. In contrast, the strains of R. trifolii examined belonged to R. leguminosarum and thus R. trifolii is a later synonym of R. leguminosarum. The results of the analysis of 16S-23S intergenic spacer region and rrs, recA and atpD gene sequences as well as those of DNA-DNA hybridization experiments and phenotypic characterizations showed that the type strains R. leguminosarum USDA 2370(T) and R. leguminosarum DSM 30132 do not belong to the same species. Taking into account that strain USDA 2370(T) corresponds to the original strain of this species, 3Hoq18(T), this strain should be considered as the true type strain of R. leguminosarum whereas strain DSM 30132 should be reclassified as a different species, for which the name Rhizobium pisi sp. nov. is proposed (type strain, DSM 30132(T)=NCIMB 11478(T)).
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Affiliation(s)
- Martha Helena Ramírez-Bahena
- Departamento de Microbiología y Genética, Edificio Departamental, Campus Miguel de Unamuno, Universidad de Salamanca, Spain
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García-Fraile P, Velázquez E, Mateos PF, Martínez-Molina E, Rivas R. Cohnella phaseoli sp. nov., isolated from root nodules of Phaseolus coccineus in Spain, and emended description of the genus Cohnella. Int J Syst Evol Microbiol 2008; 58:1855-9. [PMID: 18676468 DOI: 10.1099/ijs.0.65468-0] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A bacterial strain designated GSPC1 T was isolated from root nodules of Phaseolus coccineus in Segovia (Spain). The 16S rRNA gene sequence of this strain showed 95.9 and 94.7 % sequence similarity, respectively, with those of the type strains of Cohnella hongkongensis and Cohnella thermotolerans. Strain GSPC1 T presented phenotypic, chemotaxonomic and molecular differences with respect to Cohnella species which indicated that it belonged to a different species. The isolate was a Gram-positive, aerobic, sporulated rod, motile by means of peritrichous flagella. The strain was catalase-positive and showed weak oxidase activity. It grew in the presence of 2 % NaCl. MK-7 was the predominant menaquinone. anteiso-C15:0, iso-C15:0, iso-C16: 0 and C16:0 were the major fatty acids. Major polar lipids were diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine. The G+C content was 60.3 mol%. The results of this study suggest that isolate GSPC1 T should be classified within a novel Cohnella species, for which the name Cohnella phaseoli sp. nov. is proposed, with strain GSPC1T (=LMG 24086T =DSM 19269T) as the type strain.
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Affiliation(s)
- Paula García-Fraile
- Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain
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Rivas R, García-Fraile P, Zurdo-Piñeiro JL, Mateos PF, Martínez-Molina E, Bedmar EJ, Sánchez-Raya J, Velázquez E. Saccharibacillus sacchari gen. nov., sp. nov., isolated from sugar cane. Int J Syst Evol Microbiol 2008; 58:1850-4. [PMID: 18676467 DOI: 10.1099/ijs.0.65499-0] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A bacterial strain designated GR21T was isolated from apoplastic fluid of Saccharum officinarum (sugar cane). Phylogenetic analysis based on 16S rRNA gene sequences showed that the isolate forms a separate branch within the family 'Paenibacillaceae', with Paenibacillus as the closest related genus. Within this genus, the closest related species is Paenibacillus xylanilyticus, with 93.4 % similarity to the sequence of the type strain. The isolate has Gram-variable, facultatively anaerobic, rod-shaped cells, motile by polar and subpolar flagella. Round, non-ornamented, central or subterminal spores are formed in unswollen sporangia. The strain is catalase-positive and oxidase-negative on nutrient agar medium. Cellulose and aesculin were hydrolysed, whereas xylan, starch and gelatin were not. Growth was supported by many carbohydrates as carbon sources. Strain GR21T displayed a lipid profile consisting of diphosphatidylglycerol, phosphatidylglycerol, an unknown aminophospholipid, two unknown glycolipids and an unknown phosphoglycolipid. MK-7 was the predominant menaquinone and anteiso-C15: 0 was the major fatty acid. The DNA G+C content was 57.8 mol%. Phylogenetic and phenotypic analyses, including assimilation of carbon sources and exoenzyme production commonly used for classification within the family 'Paenibacillaceae', showed that strain GR21T belongs to a new genus within this family, for which the name Saccharibacillus sacchari gen. nov., sp. nov. is proposed. The type strain of Saccharibacillus sacchari is GR21T (=LMG 24085T =DSM 19268T).
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Affiliation(s)
- Raúl Rivas
- Departamento de Microbiología y Genética, Lab 209, Edificio Departamental de Biología Campus Miguel de Unamuno, Universidad de Salamanca, Spain
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Del Villar M, Rivas R, Peix A, Mateos PF, Martínez-Molina E, van Berkum P, Willems A, Velázquez E. Stable low molecular weight RNA profiling showed variations within Sinorhizobium meliloti and Sinorhizobium medicae nodulating different legumes from the alfalfa cross-inoculation group. FEMS Microbiol Lett 2008; 282:273-81. [PMID: 18399993 DOI: 10.1111/j.1574-6968.2008.01139.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Four different low molecular weight (LMW) RNA profiles, designated I-IV, among 179 isolates from Medicago, Melilotus and Trigonella species growing in a field site in Northern Spain were identified. From sequence analysis of the 16S rRNA, atpD and recA genes as well as DNA-DNA hybridization analysis with representatives of each LMW RNA profile it was evident that isolates with LMW RNA profiles I and II belonged to Sinorhizobium meliloti and those displaying profiles III and IV to Sinorhizobium medicae. Therefore, two distinct LMW RNA electrophoretic mobility profiles were found within each of these two species. Collectively, LMW RNA profiles I and II (identified as S. meliloti) were predominant in Melilotus alba, Melilotus officinalis and Medicago sativa. Profiles III and IV (identified as S. medicae) were predominant in Melilotus parviflora, Medicago sphaerocarpa, Medicago lupulina and Trigonella foenum-graecum. All the four LMW RNA profiles were identified among isolates from Trigonella monspelliaca nodules. These results revealed a different specificity by the hosts of the alfalfa cross-inoculation group towards the two bacterial species found in this study.
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Affiliation(s)
- María Del Villar
- Departamento de Microbiología y Genética, Universidad de Salamanca, Spain
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Iglesias O, Rivas R, GarcÃa-Fraile P, Abril A, Mateos PF, Martinez-Molina E, Velázquez E. Genetic characterization of fast-growing rhizobia able to nodulateProsopis albain North Spain. FEMS Microbiol Lett 2007; 277:210-6. [DOI: 10.1111/j.1574-6968.2007.00968.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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Zurdo-Piñeiro JL, Rivas R, Trujillo ME, Vizcaíno N, Carrasco JA, Chamber M, Palomares A, Mateos PF, Martínez-Molina E, Velázquez E. Ochrobactrum cytisi sp. nov., isolated from nodules of Cytisus scoparius in Spain. Int J Syst Evol Microbiol 2007; 57:784-788. [PMID: 17392207 DOI: 10.1099/ijs.0.64613-0] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Two strains named ESC1(T) and ESC5 were isolated from nodules of Cytisus scoparius growing in a Spanish soil. Phylogenetic analysis of the 16S rRNA gene showed that these strains belong to the genus Ochrobactrum, their closest relatives being Ochrobactrum anthropi and Ochrobactrum lupini, with 100 and 99.9 % similarity to the respective type strains. Despite this high similarity, the results of DNA-DNA hybridization, phenotypic tests and fatty acid analyses showed that these strains represent a novel species of genus Ochrobactrum. The DNA-DNA hybridization values were respectively 70, 66 and 55 % with respect to O. lupini LUP21(T), O. anthropi DSM 6882(T) and Ochrobactrum tritici DSM 13340(T). The predominant fatty acids were C(18 : 1)omega7c and C(18 : 1) 2-OH. Strains ESC1(T) and ESC5 were strictly aerobic and were able to reduce nitrate and to hydrolyse aesculin. They produced beta-galactosidase and beta-glucosidase and did not produce urease after 48 h incubation. The G+C content of strain ESC1(T) was 56.4 mol%. Both strains ESC1(T) and ESC5 contained nodD and nifH genes on megaplasmids that were related phylogenetically to those of rhizobial strains nodulating Phaseolus, Leucaena, Trifolium and Lupinus. From the results of this work, we propose that the strains isolated in this study be included in a novel species named Ochrobactrum cytisi sp. nov. The type strain is ESC1(T) (=LMG 22713(T)=CECT 7172(T)).
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Affiliation(s)
| | - Raúl Rivas
- Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain
| | - Martha E Trujillo
- Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain
| | - Nieves Vizcaíno
- Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain
| | | | | | - Antonio Palomares
- Departamento de Microbiología y Parasitología, Facultad de Farmacia, Universidad de Sevilla, Sevilla, Spain
| | - Pedro F Mateos
- Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain
| | | | - Encarna Velázquez
- Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain
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Peix A, Valverde A, Rivas R, Igual JM, Ramírez-Bahena MH, Mateos PF, Santa-Regina I, Rodríguez-Barrueco C, Martínez-Molina E, Velázquez E. Reclassification of Pseudomonas aurantiaca as a synonym of Pseudomonas chlororaphis and proposal of three subspecies, P. chlororaphis subsp. chlororaphis subsp. nov., P. chlororaphis subsp. aureofaciens subsp. nov., comb. nov. and P. chlororaphis subsp. aurantiaca subsp. nov., comb. nov. Int J Syst Evol Microbiol 2007; 57:1286-1290. [PMID: 17551044 DOI: 10.1099/ijs.0.64621-0] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Pseudomonas chlororaphis, Pseudomonas aureofaciens and Pseudomonas aurantiaca were considered as separate species until 1989, when P. aureofaciens was proposed as a later heterotypic synonym of P. chlororaphis with P. aurantiaca remaining as a separate species. Nevertheless, analysis of the almost complete 16S rRNA gene sequences revealed that the type strain of P. aurantiaca, NCIMB 10068(T), shows gene sequence similarities close to 99.5 % with respect to P. chlororaphis DSM 50083(T) and P. aureofaciens DSM 6698(T). DNA-DNA hybridization experiments among strains of P. aurantiaca, P. chlororaphis and P. aureofaciens showed values higher than 70 %, confirming that they represent members of the same species. The results of fatty acid analysis and phenotypic traits showed that these strains are closely related, although there are some differences among the strains belonging to P. aurantiaca, those from P. chlororaphis and those from P. aureofaciens. All these results confirm the previous reclassification of P. aureofaciens into P. chlororaphis and support the reclassification of P. aurantiaca as a synonym of P. chlororaphis. Phenotypic and molecular data permit the description of three novel subspecies within this last species, for which the following names are proposed: P. chlororaphis subsp. chlororaphis subsp. nov. [with the type strain DSM 50083(T) (=ATCC 9446(T)=NCIMB 9392(T))], P. chlororaphis subsp. aureofaciens subsp. nov., comb. nov. [with the type strain DSM 6698(T) (=ATCC 13985(T)=NCIMB 9030(T))] and P. chlororaphis subsp. aurantiaca subsp. nov., comb. nov. [with the type strain NCIMB 10068(T) (=ATCC 33663(T)=CIP 106718(T))].
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MESH Headings
- Bacterial Typing Techniques
- DNA, Bacterial/chemistry
- DNA, Bacterial/genetics
- DNA, Ribosomal/chemistry
- DNA, Ribosomal/genetics
- Fatty Acids/analysis
- Genes, rRNA
- Molecular Sequence Data
- Nucleic Acid Hybridization
- Phylogeny
- Pseudomonas/chemistry
- Pseudomonas/classification
- Pseudomonas/genetics
- RNA, Bacterial/genetics
- RNA, Ribosomal, 16S/genetics
- Sequence Analysis, DNA
- Sequence Homology, Nucleic Acid
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Affiliation(s)
- Alvaro Peix
- IRNASA-CSIC, Apdo 257, 37071 Salamanca, Spain
| | | | - Raúl Rivas
- Departamento de Microbiología y Genetica, Universidad de Salamanca, Spain
| | - José M Igual
- Departamento de Microbiología y Genetica, Universidad de Salamanca, Spain
| | | | - Pedro F Mateos
- Departamento de Microbiología y Genetica, Universidad de Salamanca, Spain
| | | | | | | | - Encarna Velázquez
- Departamento de Microbiología y Genetica, Universidad de Salamanca, Spain
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Rivas R, García-Fraile P, Peix A, Mateos PF, Martínez-Molina E, Velázquez E. Alcanivorax balearicus sp. nov., isolated from Lake Martel. Int J Syst Evol Microbiol 2007; 57:1331-1335. [PMID: 17551053 DOI: 10.1099/ijs.0.64912-0] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A bacterial strain designated MACL04(T) was isolated from Lake Martel, a subterraneous saline lake in Mallorca (Spain). The complete 16S rRNA gene sequence of this strain showed nearly 100 % similarity to that of Alcanivorax dieselolei B-5(T). Despite this high similarity, strain MACL04(T) showed phenotypic, chemotaxonomic and molecular differences with respect to A. dieselolei, indicating that strain MACL04(T) represents a separate species. Cells of strain MACL04(T) were motile by means of a single polar or subpolar flagellum and colonies formed on media containing 1 % (v/v) Tween 20 were opaque and mucoid, with blue-green iridescence. The generation time of strain MACL04(T) in this medium was approximately half that of A. dieselolei B-5(T) and strain MACL04(T) did not produce lipases after incubation for 5 days. Strain MACL04(T) did not require NaCl for growth and grew in the presence of up to 15 % (w/v) NaCl. The strain was able to use alkanes as a sole carbon source; however, glucose could also be used, albeit weakly, as a carbon source. Several amino acids and organic acids were used as carbon sources. Strain MACL04(T) produced acid in media containing pyruvate as the sole carbon source. The major fatty acids were C(19 : 0) cyclo omega8c and C(16 : 0). The fatty acid C(16 : 1)omega8c, present in strain MACL04(T), was not detected in the recognized Alcanivorax species. The sequences of the large and short 16S-23S intergenic spacer regions showed similarities of 97.2 and 98.8 % (ungapped) with respect to A. dieselolei B-5(T). Partial sequences of gyrB and alkb genes showed 94.0 % similarity between strain MACL04(T) and A. dieselolei B-5(T). The G+C content of strain MACL04(T) was 62.8 mol%. The data from this polyphasic study indicate that strain MACL04(T) represents a novel species of the genus Alcanivorax, for which the name Alcanivorax balearicus sp. nov. is proposed. The type strain is MACL04(T) (=LMG 22508(T)=CECT 5683(T)).
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MESH Headings
- Alcanivoraceae/classification
- Alcanivoraceae/drug effects
- Alcanivoraceae/isolation & purification
- Alcanivoraceae/physiology
- Alkanes/metabolism
- Amino Acids/metabolism
- Anti-Bacterial Agents/pharmacology
- Bacterial Proteins/genetics
- Bacterial Typing Techniques
- Base Composition
- Carboxylic Acids/metabolism
- DNA Gyrase/genetics
- DNA, Bacterial/chemistry
- DNA, Bacterial/genetics
- DNA, Ribosomal/chemistry
- DNA, Ribosomal/genetics
- DNA, Ribosomal Spacer/chemistry
- DNA, Ribosomal Spacer/genetics
- Fatty Acids/analysis
- Flagella/physiology
- Genes, rRNA
- Lipase/analysis
- Locomotion
- Mixed Function Oxygenases/genetics
- Molecular Sequence Data
- Phylogeny
- RNA, Bacterial/genetics
- RNA, Ribosomal, 16S/genetics
- Saline Solution, Hypertonic/pharmacology
- Sequence Analysis, DNA
- Sequence Homology, Nucleic Acid
- Spain
- Water Microbiology
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Affiliation(s)
- Raúl Rivas
- Laboratorium voor Microbiologie, Vakgroep Biochemie, Fysiologie en Microbiologie, Universiteit Gent KL, Ledeganckstraat 35, B-9000 Gent, Belgium
- Departamento de Microbiología y Genética, Universidad de Salamanca, Spain
| | | | - Alvaro Peix
- Instituto de Recursos Naturales y Agrobiología, IRNASA-CSIC, Salamanca, Spain
| | - Pedro F Mateos
- Departamento de Microbiología y Genética, Universidad de Salamanca, Spain
| | | | - Encarna Velázquez
- Departamento de Microbiología y Genética, Universidad de Salamanca, Spain
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Rivas R, Laranjo M, Mateos PF, Oliveira S, Martínez-Molina E, Velázquez E. Strains of Mesorhizobium amorphae and Mesorhizobium tianshanense, carrying symbiotic genes of common chickpea endosymbiotic species, constitute a novel biovar (ciceri) capable of nodulating Cicer arietinum. Lett Appl Microbiol 2007; 44:412-8. [PMID: 17397480 DOI: 10.1111/j.1472-765x.2006.02086.x] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
AIMS To identify several strains of Mesorhizobium amorphae and Mesorhizobium tianshanense nodulating Cicer arietinum in Spain and Portugal, and to study the symbiotic genes carried by these strains. METHODS AND RESULTS The sequences of 16S-23S intergenic spacer (ITS), 16S rRNA gene and symbiotic genes nodC and nifH were analysed. According to their 16S rRNA gene and ITS sequences, the strains from this study were identified as M. amorphae and M. tianshanense. The type strains of these species were isolated in China from Glycyrrhiza pallidiflora and Amorpha fruticosa nodules, respectively, and are not capable of nodulating chickpea. These strains carry symbiotic genes, phylogenetically divergent from those of the chickpea isolates, whose nodC and nifH genes showed more than 99% similarity with respect to those from Mesorhizobium ciceri and Mesorhizobium mediterraneum, the two common chickpea nodulating species in Spain and Portugal. CONCLUSIONS The results from this study showed that different symbiotic genes have been acquired by strains from the same species during their coevolution with different legumes in distinct geographical locations. SIGNIFICANCE AND IMPACT OF THE STUDY A new infrasubspecific division named biovar ciceri is proposed within M. amorphae and M. tianshanense to include the strains able to effectively nodulate Cicer arietinum.
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Affiliation(s)
- R Rivas
- Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain
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García-Fraile P, Rivas R, Willems A, Peix A, Martens M, Martínez-Molina E, Mateos PF, Velázquez E. Rhizobium cellulosilyticum sp. nov., isolated from sawdust of Populus alba. Int J Syst Evol Microbiol 2007; 57:844-848. [PMID: 17392217 DOI: 10.1099/ijs.0.64680-0] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
During a study of polysaccharide-hydrolysing bacteria present in different plant sources, two strains were isolated from pulverized decaying wood of Populus alba and classified in the genus Rhizobium on basis of their almost complete 16S rRNA gene sequences. Their closest phylogenetic relatives were Rhizobium galegae USDA 4128T and Rhizobium huautlense S02T, with 98.2 and 98.1 % 16S rRNA gene sequence similarity, respectively. recA and atpD sequence analysis showed that these species have less than 88 and 92 % similarity, respectively, to the novel strains. In contrast to their closest phylogenetic relatives, the two strains showed strong cellulase activity on plates containing CM-cellulose as a carbon source. They were also distinguishable from these species on the basis of other phenotypic characteristics. The strains were able to induce ineffective nodules on Medicago sativa and the sequence of their nodD gene was phylogenetically close to that of Ensifer meliloti 1021 (99.6 % similarity). DNA–DNA hybridization values ranged from 10 to 22 % with respect to R. galegae USDA 4128T and 14 to 25 % with respect to R. huautlense S02T, showing that the strains from this study belong to a novel species, for which the name Rhizobium cellulosilyticum sp. nov. is proposed. The type strain is ALA10B2T (=LMG 23642T=DSM 18291T=CECT 7176T).
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Affiliation(s)
| | - Raúl Rivas
- Laboratorium voor Microbiologie, Vakgroep Biochemie, Fysiologie en Microbiologie, Universiteit Gent, K. L. Ledeganckstraat 35, B-9000 Gent, Belgium
- Departamento de Microbiología y Genética, Universidad de Salamanca, Spain
| | - Anne Willems
- Laboratorium voor Microbiologie, Vakgroep Biochemie, Fysiologie en Microbiologie, Universiteit Gent, K. L. Ledeganckstraat 35, B-9000 Gent, Belgium
| | - Alvaro Peix
- Instituto de Recursos Naturales y Agrobiología, IRNA-CSIC, Salamanca, Spain
| | - Miet Martens
- Laboratorium voor Microbiologie, Vakgroep Biochemie, Fysiologie en Microbiologie, Universiteit Gent, K. L. Ledeganckstraat 35, B-9000 Gent, Belgium
| | | | - Pedro F Mateos
- Departamento de Microbiología y Genética, Universidad de Salamanca, Spain
| | - Encarna Velázquez
- Departamento de Microbiología y Genética, Universidad de Salamanca, Spain
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Rivas R, García-Fraile P, Mateos PF, Martínez-Molina E, Velázquez E. Paenibacillus cellulosilyticus sp. nov., a cellulolytic and xylanolytic bacterium isolated from the bract phyllosphere of Phoenix dactylifera. Int J Syst Evol Microbiol 2007; 56:2777-2781. [PMID: 17158977 DOI: 10.1099/ijs.0.64480-0] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A bacterial strain designated PALXIL08(T) was isolated from the phyllosphere of Phoenix dactylifera bracts. A phylogenetic analysis based on the 16S rRNA gene sequence placed the isolate within the genus Paenibacillus in the same subgroup as Paenibacillus kobensis and Paenibacillus curdlanolyticus (98.9 and 97.9 % sequence similarity, respectively). The DNA hybridization values between the isolate and the type strains of Paenibacillus kobensis and Paenibacillus curdlanolyticus were found to be 27.4 and 17.6 %, respectively. The isolate comprised Gram-variable, facultatively anaerobic, motile, sporulating rods. Catalase and oxidase were produced and cellulose, xylan, starch and aesculin were hydrolysed. Many carbohydrates served as carbon sources for growth. MK-7 was the predominant menaquinone, and anteiso-C(15 : 0) and iso-C(16 : 0) were the major fatty acids. The DNA G+C content was 51 mol%. DNA relatedness data and the results of phylogenetic and phenotypic analyses showed that strain PALXIL08(T) should be considered as the type strain of a novel species of the genus Paenibacillus, for which the name Paenibacillus cellulosilyticus sp. nov. is proposed. The type strain is PALXIL08(T) (=LMG 22232(T)=CECT 5696(T)).
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Affiliation(s)
- Raúl Rivas
- Departamento de Microbiología y Genética, Edificio Departamental, Campus Miguel de Unamuno, Universidad de Salamanca, 37007 Salamanca, Spain
| | - Paula García-Fraile
- Departamento de Microbiología y Genética, Edificio Departamental, Campus Miguel de Unamuno, Universidad de Salamanca, 37007 Salamanca, Spain
| | - Pedro F Mateos
- Departamento de Microbiología y Genética, Edificio Departamental, Campus Miguel de Unamuno, Universidad de Salamanca, 37007 Salamanca, Spain
| | - Eustoquio Martínez-Molina
- Departamento de Microbiología y Genética, Edificio Departamental, Campus Miguel de Unamuno, Universidad de Salamanca, 37007 Salamanca, Spain
| | - Encarna Velázquez
- Departamento de Microbiología y Genética, Edificio Departamental, Campus Miguel de Unamuno, Universidad de Salamanca, 37007 Salamanca, Spain
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Rivas R, García-Fraile P, Mateos PF, Martínez-Molina E, Velázquez E. Characterization of xylanolytic bacteria present in the bract phyllosphere of the date palm Phoenix dactylifera. Lett Appl Microbiol 2007; 44:181-7. [PMID: 17257258 DOI: 10.1111/j.1472-765x.2006.02050.x] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
AIMS Despite the interest of phyllosphere microbiology, no studies have addressed the bacteria present in bract phyllosphere, an ecosystem that has special characteristics in palm trees because the dry bracts remain on the plant until pruning and may contain polymer-degrading bacteria involved in plant degradation. Therefore, the aim of this work was to characterize xylanolytic bacteria isolated from palm bract phyllosphere. METHODS AND RESULTS Twelve xylanolytic strains were isolated and characterized by phenotypic features and complete sequencing of 16S rRNA gene. The results showed that the isolates were phenotypically and genotypically diverse. Gram-positive isolates were classified into genus Paenibacillus some of them belonging to hitherto undescribed species of this genus. Gram-negative isolates were classified into genera Pseudomonas and Acinetobacter. CONCLUSIONS The results of this work confirm the complexity of the bacterial populations present in phyllospheric ecosystems and suggest that bacteria involved in plant degradation are present at the early degradation steps of this process in dry palm tree bracts. SIGNIFICANCE AND IMPACT OF THE STUDY This is the first study on bract phyllospheric bacteria able to hydrolyse vegetal polymers and offers a new perspective in the search of unexplored sources of xylanase-producing strains.
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Affiliation(s)
- R Rivas
- Departamento de Microbiología y Genética, Universidad de Salamanca, 37007 Salamanca, Spain
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Rivas R, García-Fraile P, Mateos PF, Martínez-Molina E, Velázquez E. Photobacterium halotolerans sp. nov., isolated from Lake Martel in Spain. Int J Syst Evol Microbiol 2006; 56:1067-1071. [PMID: 16627656 DOI: 10.1099/ijs.0.64099-0] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A halotolerant bacterium was isolated from a saline lake located in Mallorca, Spain. Cells of the strain, designated MACL01T, were Gram-negative, rod-shaped and motile by means of polar flagella. Colonies of strain MACL01T were white to cream in TSA medium, turning brown after 7 days of incubation; they were blue in thiosulphate/citrate/bile salts/sucrose agar medium. A neighbour-joining phylogenetic analysis based on 16S rRNA gene sequences showed that strain MACL01T belongs to the genus Photobacterium, in which it forms a distinct lineage together with Photobacterium rosenbergii and Photobacterium ganghwense (showing 96.9 and 96.2 % similarity, respectively). The most closely related taxon according to phylogenetic analysis of the rpoA gene is also P. rosenbergii (90 % similarity). The recA gene also showed low similarity (83.7, 83.4 and 82.4 %, respectively) with respect to those of Vibrio proteolyticus LMG 3772T, Photobacterium leiognathii LMG 4228T and P. rosenbergii LMG 22223T. Neighbour-joining phylogenetic analysis of the rpoA and recA genes confirms that strain MACL01T belongs to the genus Photobacterium, forming a branch together with P. rosenbergii. Strain MACL01T was able to grow in 0–8 % NaCl. Growth occurred between 4 and 37 °C (optimum, 28 °C) and at pH 5–8.5. Luminescence was negative on marine agar. Strain MACL01T was found to be sensitive to the vibriostatic agent O/129. It reduced nitrate to nitrite, produced β-galactosidase and hydrolysed gelatin, but did not produce arginine dihydrolase, indole or acetoin. Strain MACL01T used several carbohydrates and fermented glucose, l-arabinose and sucrose. The most abundant fatty acids were summed feature 3 (32.6 %; comprising C16 : 1
ω7c and/or C15 : 0 iso 2-OH), C16 : 0 (21.2 %) and C18 : 1
ω7c (19.9 %). The G+C content of the genomic DNA was 49.8 mol%. On the basis of genotypic, phenotypic, chemotaxonomic and phylogenetic results, strain MACL01T (=LMG 22194T=CECT 5860T) should be classified as the type strain of a novel species of the genus Photobacterium, for which the name Photobacterium halotolerans sp. nov. is proposed.
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Affiliation(s)
- Raúl Rivas
- Departamento de Microbiología y Genética, Lab. 209, Edificio Departamental de Biología, Campus Miguel de Unamuno, Universidad de Salamanca, 37007 Salamanca, Spain
| | - Paula García-Fraile
- Departamento de Microbiología y Genética, Lab. 209, Edificio Departamental de Biología, Campus Miguel de Unamuno, Universidad de Salamanca, 37007 Salamanca, Spain
| | - Pedro F Mateos
- Departamento de Microbiología y Genética, Lab. 209, Edificio Departamental de Biología, Campus Miguel de Unamuno, Universidad de Salamanca, 37007 Salamanca, Spain
| | - Eustoquio Martínez-Molina
- Departamento de Microbiología y Genética, Lab. 209, Edificio Departamental de Biología, Campus Miguel de Unamuno, Universidad de Salamanca, 37007 Salamanca, Spain
| | - Encarna Velázquez
- Departamento de Microbiología y Genética, Lab. 209, Edificio Departamental de Biología, Campus Miguel de Unamuno, Universidad de Salamanca, 37007 Salamanca, Spain
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Velázquez E, Rivas R, del Villar M, Valverde A, Peix A, Mateos PF, Velázquez E, Martínez-Molina E. A new approach for separating low-molecular-weight RNA molecules by staircase electrophoresis in non-sequencing gels. Electrophoresis 2006; 27:1732-8. [PMID: 16586413 DOI: 10.1002/elps.200500705] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Low-molecular-weight (LMW) RNA profiles, which include ribosomal and transfer RNA molecules with similar small sizes, are molecular signatures of microorganisms with a great potential in microbial identification. The greatest resolution of these profiles was achieved by staircase electrophoresis in sequencing gels. Nevertheless, this technique is difficult to use because it takes 7 h, the gels have large sizes and it is necessary to heat the system and to recycle the buffer to maintain the denaturing conditions and avoid smile effects. Most available sequencing slabs have no internal temperature control or homogenizing devices, which by contrast are present in some newly designed non-sequencing slabs. Nevertheless, these slabs present two important problems for separating LMW RNA molecules, the size of gels is only 20 cm (instead of 40 cm) and the maximum voltage that can be reached is only 840 V (instead 2400 V). Staircase electrophoresis follows a model in which the external polarization is incrementally modified with a constant time step value. In the present work, we experimentally confirmed that by reducing the time step and increasing the total number of steps a suitable resolution is achieved. Under these conditions, despite the smaller size of the gels and the lower values of the electric field, the intensity reaches higher values than in sequencing gels and the LMW RNA profiles are correctly separated in 5 h. The resolution of these profiles obtained in non-sequencing gels is similar to that obtained in sequencing ones facilitating the analysis of large populations of microorganisms in any laboratory.
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Affiliation(s)
- Encarna Velázquez
- Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain.
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Peix A, Rivas R, Velázquez E, Mateos PF, Martínez-Molina E, Muñoz-Herrera A, Gómez-Alonso A, Velázquez E. Application of horizontal staircase electrophoresis in agarose minigels to the random intergenic spacer analysis of clinical samples. Electrophoresis 2005; 26:4402-10. [PMID: 16315171 DOI: 10.1002/elps.200500357] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The random intergenic spacer analysis is a recently developed technique for the study of microbial populations. The bacterial intergenic spacer (ITS) is located between 16S rRNA and 23S rRNA genes and presents different length and sequence among bacterial species. Therefore, the amplicons can be separated by electrophoresis commonly performed at low voltage during several hours. Although this technique is especially useful for unculturable microorganisms, it has not been applied before to clinical sample analysis. As these samples have a limited number of bacterial species, the size of the gels may be reduced to facilitate their handling and to reduce the running time. To obtain maximum separation among the ITS bands, we analysed in this work different electrophoretical conditions including staircase electrophoresis, a technique based on the application of several voltage steps. The results obtained showed a different behaviour of the electrical resistance during the performance of submarine horizontal and vertical staircase electrophoresis. In the first case the resistance decreased during most of the running time whereas in the second case it increased. Here, we show that the performance of horizontal staircase electrophoresis reduces the running time more than 80% with respect to conventional electrophoresis at low voltages. This procedure was applied to the separation of ITS bands from bacterial DNA present in a tissue from a vocal cord biopsy. The sequencing of these bands allowed their identification. This new procedure may be very useful in the rapid diagnosis of bacteria present in human, animal and plant tissues.
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Affiliation(s)
- Alvaro Peix
- Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain
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Velázquez E, Peix A, Zurdo-Piñeiro JL, Palomo JL, Mateos PF, Rivas R, Muñoz-Adelantado E, Toro N, García-Benavides P, Martínez-Molina E. The coexistence of symbiosis and pathogenicity-determining genes in Rhizobium rhizogenes strains enables them to induce nodules and tumors or hairy roots in plants. Mol Plant Microbe Interact 2005; 18:1325-32. [PMID: 16478052 DOI: 10.1094/mpmi-18-1325] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Bacteria belonging to the family Rhizobiaceae may establish beneficial or harmful relationships with plants. The legume endosymbionts contain nod and nif genes responsible for nodule formation and nitrogen fixation, respectively, whereas the pathogenic strains carry vir genes responsible for the formation of tumors or hairy roots. The symbiotic and pathogenic strains currently belong to different species of the genus Rhizobium and, until now, no strains able to establish symbiosis with legumes and also to induce tumors or hairy roots in plants have been reported. Here, we report for the first time the occurrence of two rhizobial strains (163C and ATCC11325T) belonging to Rhizobium rhizogenes able to induce hairy roots or tumors in plants and also to nodulate Phaseolus vulgaris under natural environmental conditions. Symbiotic plasmids (pSym) containing nod and nif genes and pTi- or pRi-type plasmids containing vir genes were found in these strains. The nodD and nifH genes of the strains from this study are phylogenetically related to those of Sinorhizobium strains nodulating P. vulgaris. The virA and virB4 genes from strain 163C are phylogenetically related to those of R. tumefaciens C58, whereas the same genes from strain ATCC 11325T are related to those of hairy root-inducing strains. These findings may be of high relevance for the better understanding of plant-microbe interactions and knowledge of rhizobial phylogenetic history.
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Affiliation(s)
- Encarna Velázquez
- Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain.
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Valverde A, Velázquez E, Fernández-Santos F, Vizcaíno N, Rivas R, Mateos PF, Martínez-Molina E, Igual JM, Willems A. Phyllobacterium trifolii sp. nov., nodulating Trifolium and Lupinus in Spanish soils. Int J Syst Evol Microbiol 2005; 55:1985-1989. [PMID: 16166699 DOI: 10.1099/ijs.0.63551-0] [Citation(s) in RCA: 117] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Bacterial strain PETP02T was isolated from nodules of Trifolium pratense growing in a Spanish soil. Phylogenetic analysis of the 16S rRNA gene sequence showed that this strain represents a member of the genus Phyllobacterium. However, divergence found with the 16S rRNA gene sequence of the single recognized species of this genus, Phyllobacterium myrsinacearum, indicated that strain PETP02T belongs to a different species. The results of DNA–DNA hybridization, phenotypic tests and fatty acid analyses confirmed that this strain represents a novel species of the genus Phyllobacterium, for which the name Phyllobacterium trifolii sp. nov. is proposed. The type strain is PETP02T (=LMG 22712T=CECT 7015T). This strain was strictly aerobic and used several carbohydrates as carbon source. It was not able to reduce nitrate. Aesculin hydrolysis was negative. It did not produce urease, arginine dihydrolase, gelatinase or β-galactosidase. The DNA G+C content was 56·4 mol%. The nodD gene of this strain showed a sequence closely related to those of strains able to nodulate Lupinus. Infectivity tests showed that this strain is able to produce nodules in both Trifolium repens and Lupinus albus.
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Affiliation(s)
- Angel Valverde
- Departamento de Producción Vegetal, IRNA-CSIC, Salamanca, Spain
| | - Encarna Velázquez
- Departamento de Microbiología y Genética, Lab 209, Edificio Departamental de Biología, Campus Miguel de Unamuno, Universidad de Salamanca, 37007 Salamanca, Spain
| | - Félix Fernández-Santos
- Departamento de Microbiología y Genética, Lab 209, Edificio Departamental de Biología, Campus Miguel de Unamuno, Universidad de Salamanca, 37007 Salamanca, Spain
| | - Nieves Vizcaíno
- Departamento de Microbiología y Genética, Lab 209, Edificio Departamental de Biología, Campus Miguel de Unamuno, Universidad de Salamanca, 37007 Salamanca, Spain
| | - Raúl Rivas
- Departamento de Microbiología y Genética, Lab 209, Edificio Departamental de Biología, Campus Miguel de Unamuno, Universidad de Salamanca, 37007 Salamanca, Spain
| | - Pedro F Mateos
- Departamento de Microbiología y Genética, Lab 209, Edificio Departamental de Biología, Campus Miguel de Unamuno, Universidad de Salamanca, 37007 Salamanca, Spain
| | - Eustoquio Martínez-Molina
- Departamento de Microbiología y Genética, Lab 209, Edificio Departamental de Biología, Campus Miguel de Unamuno, Universidad de Salamanca, 37007 Salamanca, Spain
| | | | - Anne Willems
- Laboratorium voor Microbiologie, Vakgroep Biochemie, Fysiologie en Microbiologie, Universiteit Gent, K.L. Ledeganckstraat 35, B-9000 Gent, Belgium
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