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Nitrogen Metabolism

María J. Delgado Igeño (PI)

Scientific Researcher CSIC

F-2683-2017

0000-0003-2410-9484

mariajesus.delgado@eez.csic.es

PHONE NUMBER

+34 958-181600 ext. 439180

Other group members

María Socorro Mesa Banqueri

Tenured Scientist CSIC

Germán Tortosa Muñoz

Técnico Especializado

Alba Hidalgo García

Indefinido no fijo

Juan José Cabrera Rodríguez

Postdoc

Andrea Jiménez Leiva

Postdoc, Junta de Andalucía

Sofía Guzmán García

Garantía Juvenil Contract

Raquel Adriana Juárez Martos

Predoc FPU

Noemí Fernández Fernández

Predoc

Research lines

  • Study the environmental factors, genes, enzymes and redox processes involved in the denitrification pathway of legume endosymbiotic bacteria.
  • Unravel the molecular mechanisms that control the expression, activity and regulation of denitrification and nitrogen fixation-related processes during symbiosis.
  • Analyse the molecular ecology of nitrifying and denitrifying bacteria in soils, waters and sediments contaminated with nitrates. Effect of nitrogen fertilization.
  • Determine the environmental and regulatory factors involved in reducing the emission of the greenhouse gas nitrous oxide by endosymbiotic bacteria associated with legume crops.
  • Development of organic and biological fertilizers based on agricultural organic wastes composting.

Representative publications

  • Jindo K, Goron TL, Pizarro-Tobías P, Sánchez-Monedero MÁ, Audette Y, Deolu-Ajayi AO, van der Werf A, Goitom Teklu M, Shenker M, Pombo Sudré C, Busato JG, Ochoa-Hueso R, Nocentini M, Rippen J, Aroca R, Mesa S, Delgado MJ, Tortosa G (2022). Application of biostimulant products and biological control agents in sustainable viticulture: A review. Frontiers in Plant Science, 13, 932311. DOI: 10.3389/fpls.2022.932311.
  • Parejo S, Cabrera JJ, Jiménez-Leiva A, Tomás-Gallardo L, Bedmar EJ, Gates AJ, Mesa S. (2022). Fine-tuning modulation of oxidation-mediated posttranslational control of Bradyrhizobium diazoefficiens FixK2 transcription factor. J. Mol. Sci. 23:5117. DOI: 10.3390/ijms23095117.
  • Pacheco PJ, Cabrera JJ, Jiménez-Leiva A, Bedmar EJ, Mesa S, Tortosa G, Delgado MJ (2022). Effect of Copper on Expression of Functional Genes and Proteins Associated with Bradyrhizobium diazoefficiens International Journal of Molecular Sciences, 23, 3386 (doi: 10.3390/ijms23063386).
  • Cabrera JJ, Jiménez-Leiva A, Tomás-Gallardo L, Parejo S, Casado S, Torres MJ, Bedmar EJ, Delgado MJ, Mesa S (2021). Dissection of FixK2 protein–DNA interaction unveils new insights into Bradyrhizobium diazoefficiens lifestyles control. Environmental Microbiology, 2021, 23, pp. 6194–6209. (doi: 10.1111/1462-2920.15661).
  • Bueno E, Mania D, Mesa S, Bedmar EJ, Frostegard A, Bakken LR, Delgado MJ (2022). Regulation of the emissions of the greenhouse gas nitrous oxide by the soybean endosymbiont Bradyrhizobium diazoefficiens. International Journal of Molecular Sciences, 2022, 23, 1486.
  • Salas A, Cabrera JJ, Jimenez-Leiva A, Mesa S, Bedmar EJ, Richardson DJ, Gates AJ & Delgado MJ. (2021). Bacterial nitric oxide metabolism: Recent insights in rhizobia. Advances in Microbial Physiology, 78, 261-300. (doi: 10.1016/bs.ampbs.2021.05.001).
  • Tortosa G, Fernández-González AJ, Lasa AV, Aranda E, Torralbo F, González-Murua C, Fernández-López M, Benítez E, Bedmar EJ. (2021). Involvement of the metabolically active bacteria in the organic matter degradation during olive mill waste composting. Science of the Total Environment, 789, 147975. (doi: 10.1016/j.scitotenv.2021.147975).
  • Castellano-Hinojosa A, Correa-Galeote D, Ramírez-Bahena M-H, Tortosa G, González-López J, Bedmar EJ and Peix A. (2021). Agrobacterium leguminum nov., isolated from nodules of Phaseolus vulgaris in Spain. International Journal of Systematic and Evolutionary Microbiology. (doi: 10.1099/ijsem.0.005120).
  • Tortosa G, Pacheco PJ, Hidalgo-García A, Granados A, Delgado A, Mesa S, Bedmar EJ, Delgado MJ (2020) Copper modulates nitrous oxide emissions from soybean root nodules. Environ Exp Bot (doi.org/10.1016/j.envexpbot.2020.104262).
  • Castellano-Hinojosa A, Charteris AF, Müller C, Jansen-Willems A, González-López J, Bedmar EJ, Carrillo P. Cárdenas LM (2020) Occurrence and 15N-quantification of simultaneous nitrification and denitrification in N-fertilized soils incubated under oxygen-limiting conditions. Soil Biol Biochem (doi.org/10.1016/j.soilbio.2020.107757).
  • Salas A, Tortosa Muñoz G, Hidalgo-García A, Delgado-Huertas A, Bedmar EJ, Richardson D, Gates AJ, Delgado MJ (2020) The haemoglobin Bjgb from Bradyrhizobium diazoefficiens controls NO homeostasis in soybean nodules to protect symbiotic nitrogen fixation. Front Microbiol (doi).
  • Hidalgo-García A, Torres MJ, Salas A, Bedmar EJ, Girard L, Delgado MJ (2019) Rhizobium etli produces nitrous oxide by coupling the assimilatory and denitrification pathways. Front Microbiol (doi: 10.3389/fmicb.2019.00980).
  • Castellano-Hinojosa A, Correa-Galeote D, González-López J, Bedmar EJ (2019) Effect of nitrogen fertilizers on nitrous oxide emission, nitrifier and denitrifier abundance and bacterial diversity in closed ecological systems. App Soil Ecol (doi: 10.1016/j.apsoil. 2019.103380).
  • Jiménez-Leiva A, Cabrera JJ, Bueno E, Torres MJ, Salazar S, Bedmar EJ, Delgado EJ, Mesa S (2019) Expanding the regulon of the Bradyrhizobium diazoefficiens NnrR transcription factor: new insights into the denitrification pathway. Front Microbiol 10: 1926 (doi: 10.3389/fmicb.2019.01926).
  • Fernández N, Cabrera, JJ, Varadarajan AR, Lutz S, Ledermann R, Roschitzki B, L. Eberl L, Bedmar EJ, Fischer HM, Pessi G, Ahrens CH, Mesa S (2019) An integrated approach unveils new aspects of microoxia-mediated regulation in diazoefficiens. Front Microbiol 10: 924. (doi: 10.3389/fmicb.2019.00924).
  • Torres MJ, Avila S, Bedmar EJ, Delgado MJ (2018) Overexpression of the periplasmic nitrate reductase supports anaerobic growth by Ensifer meliloti. FEMS Microbiol Lett 365: 041 (doi: 10.1093/femsle/fny041).
  • Castellano-Hinojosa A. González-López J, Bedmar, EJ (2018) Distinct effect of nitrogen fertilisation and soil depth on nitrous oxide emissions and nitrifiers and denitrifiers abundance. Biol Fertility Soils (doi: 10.1007/s00374-018-1310-9).
  • Bueno E, Robles E, Torres MJ, Krell T, Bedmar EJ, Delgado MJ, Mesa S (2017) Disparate response to microoxia and nitrogen oxides of the Bradyrhizobium japonicum napEDABC, nirK and norCBQD denitrification genes. Nitric Oxide 68: 137-149.
  • Torres MJ, Simon J, Rowley G, Bedmar EJ, Richardson DJ, Gates AJ, Delgado MJ (2016) Nitrous oxide metabolism in nitrate-reducing bacteria: physiology and regulatory mechanisms. In: Advances in Microbial Physiology, vol 68 (Poole RK, ed.) pp 353-432. (doi:10.1016/bs.ampbs.2016.02.007).
  • Cabrera JJ, Salas A, Torres MJ, Bedmar EJ, Richardson DJ, Gates AJ, Delgado MJ (2016) An integrated system for nitrate assimilation and nitric oxide detoxification in Bradyrhizobium japonicum. Biochem J 473: 297-309.
  • Bueno E, Mania D, Frostegard Ǻ, Bedmar EJ, Bakken LR, Delgado MJ (2015) Anoxic growth of Ensifer meliloti 1021 by N2O-reduction, a potential mitigation strategy. Front Microbiol 27: (doi: 10.3389/fmicb.2015.00537).
  • Peix A, Ramírez-Bahena MH, Velázquez E, Bedmar EJ (2015) Bacterial associations with legumes. Critical Rev Plant Sci 34: 17-42.
  • Bonnet M, Kurz K, Mesa S, Briand C, Hennecke H, Grütter M (2013) Structure of Bradyrhizobium japonicum transcription factor FixK2 unveils sites of DNA binding and oxidation. J Biol Chem 288: 14238-14246.

Grants

  • Delgado MJ (IP), Tortosa G (participant) (2022-2025) Producción sostenible de leguminosas y mitigación de las emisiones de gases de efecto invernadero. Plan Estatal del Ministerio de Ciencia e Innovación, Generación del Conocimiento (PID2021-124007OB-I00).
  • Mesa S (IP), Tortosa G (participant) (2021-2024) Mecanismos de interregulación de los procesos de fijación de nitrógeno y desnitrificación en la bacteria modelo y endosimbionte de la soja Bradyrhizobium diazoefficiens. Plan Estatal del Ministerio de Ciencia e Innovación, Generación del Conocimiento (PID2020-114330GB-I00).
  • Mesa S (IP), Delgado MJ (participant), Tortosa G (participant) (2021-2022) Estudio integrado de los factores que modulan el balance de polihidroxibutirato en Bradyrhizobium diazoefficiens para su uso como inoculante más competitivo en soja y como productor de bioplásticos. Programa de Cooperación Científica para el Desarrollo” I-COOP+, modalidad B, CSIC, España. (COOPB20505).
  • Delgado MJ (IP), Mesa MS (co-IP), Bedmar EJ (participant) (2021-2023) Integrated study of the mechanisms that affect the production of greenhouse gases by endosymbiotic bacteria of legumes. Project of Excellence from Junta de Andalucía. P18-RT-1401.
  • Delgado MJ (IP), Bedmar EJ (participant) (2018-2021) Emission of nitric oxide and nitrous oxide by legume crops: Processes involved, their control and mitigation strategies. Ministry of Science and Innovation. AGL2017-85676-R.
  • Mesa MS (IP), Bedmar EJ (participant) (2016-2021) Dissection of the regulatory network that controls the FixK2 protein of Bradyrhizobium diazoefficiens, a key transcriptional factor for symbiosis. Ministry of Economy and Competitiveness. AGL2015-63651-P. Extended by an extraordinary grant from CSIC (2019AEP193).
  • Bedmar EJ (IP), Delgado MJ (participant) and MS Mesa (participant) (2014-2019) Emission of nitrous oxide by soils cultivated with legumes and vegetables of agricultural interest (Nitroleg, P12-AGR-1968). Motive Project of Junta de Andalucía.
  • Bedmar EJ (IP), Delgado (participant) and Mesa MS (participant) (2014-2015) Emission of nitrous oxide by soils cultivated with legumes and vegetables of agricultural interest and bacterial biodiversity associated with nitrogen fertilization. Special project RECUPERA 2020 in collaboration with Ministry of Economy and Competitiveness-CSIC. CSIC-902022130007.

Relevant methods

  • Gas chromatography for detection of greenhouse gases and others
  • Nitric oxide (NO) detection through the use of specific electrodes
  • Cytochrome c detection c (heme staining)
  • Western-blot and protein immunodetection
  • Expression and purification of proteins (recombinant and genuine)
  • Affinity chromatography, molecular exclusion, ion Exchange
  • DNA isolation from environmental samples
  • N-cycle genes amplification from environmental samples
  • Mass sequencing. Illumina
  • Isolation of RNA from free-living cultures and from nodules
  • Analysis of gene expression using transcriptional fusions, qRT-PCR and microarrays
  • In vitro transcription
  • Characterization of promoters using primer extension techniques (RACE, FLOE, primer extension, etc.)
  • Protein-DNA interaction: surface plasmon resonance (SPR), isothermal titration calorimetry (ITC), and electrophoretic mobility shift assay (EMSA)
  • Transcriptomics and proteomics

Collaborations with other national and international research groups

  • Xavier Barril (University of Barcelona, Spain)
  • Antonio De Ron (Misión Biológica de Galicia-CSIC, Spain)
  • Elena Evguenieva-Hackenberg (Justus-Liebig-Universität Giessen, Alemania
  • Hans Martin Fischer (Swiss Federal Institute of Technology-ETH, Switzerland)
  • Lourdes Girard (Center for Genomic Sciences, UNAM, México)
  • Gabriella Pessi y Leo Eberl (University of Zürich, Suiza)
  • Juan Ignacio Quelas (National University of La Plata/National Council for Scientific and Technical Research, Argentina)
  • María Julia Pettinari (Universidad de Buenos Aires, Argentina)
  • Marcelo Müller-Santos (Universidad Federal de Paraná, Brasil)
  • David Richardson and Andrew Gates (University of East Anglia, UK)
  • Laura Tomás-Gallardo (Andalusian Center for Development Biology, Pablo de Olavide University-CSIC, Spain)
  • Toshiki Uchiumi (University of Kagoshima, Japan)
  • Carol Viviana Amaya-Gómez (Corporación Colombiana de Investigación Agropecuaria-Agrosavia, Colombia)
  • Gustavo Curaqueo (Universidad Católica de Temuco, Chile)
  • Keiji Jindo (Wageningen University & Research, the Netherlands)