A5101834262- Legume Nitrogen Fixing Symbiosis
- Plant nutrient uptake and metabolism
- Wastewater Treatment and Nitrogen Removal
- Microbial Fuel Cells and Bioremediation
- Nematode management and characterization studies
- Cassava research and cyanide
- Coastal wetland ecosystem dynamics
- Pharmaceutical and Antibiotic Environmental Impacts
- Plant responses to water stress
- Antibiotic Resistance in Bacteria
- Molecular Biology Techniques and Applications
- Agronomic Practices and Intercropping Systems
Estación Experimental del Zaidín
2011-2025
Consejo Superior de Investigaciones Científicas
2016-2023
Experimental Station
2023
Norwich Research Park
2021
University of East Anglia
2021
Aims: To investigate the role of RegSR-NifA regulatory cascade in oxygen control nitric oxide (NO) reduction soybean endosymbiont Bradyrhizobium diazoefficiens. Results: We have performed an integrated study norCBQD expression and NO reductase activity regR, regS1, regS2, regS1/2, nifA mutants response to microoxia (2% O2) or anoxia. An activating RegR NifA was observed under In contrast, microaerobic conditions, acts as a repressor by binding box located between -10 -35 regions within...
Rhizobia are recognized to establish N2-fixing symbiotic interactions with legume plants. Bradyrhizobium japonicum, the symbiont of soybeans, can denitrify and grow under free-living conditions nitrate (NO3 (-)) or nitrite (NO2 as sole nitrogen source. Unlike related bacteria that assimilate NO3 (-), genes encoding assimilatory (-) reductase (nasC) NO2 (nirA) in B. japonicum located at distinct chromosomal loci. The nasC gene is an ABC-type transporter, a major facilitator family (-)/NO2...
The adaptation of rhizobia from the free-living state in soil to endosymbiotic comprises several physiological changes order cope with extremely low oxygen availability (microoxia) within nodules. To uncover cellular functions required for bacterial microoxia directly at protein level, we applied a systems biology approach on key rhizobial model and soybean endosymbiont Bradyrhizobium diazoefficiens USDA 110 (formerly B. japonicum 110). As first step, complete genome 110spc4, strain used...
Denitrification in the soybean endosymbiont Bradyrhizobium diazoefficiens is controlled by a complex regulatory network composed of two hierarchical cascades, FixLJ-FixK2-NnrR and RegSR-NifA. In former cascade, CRP/FNR-type transcription factors FixK2 NnrR exert disparate control on expression core denitrifying systems encoded napEDABC, nirK, norCBQD, nosRZDFYLX genes response to microoxia nitrogen oxides, respectively. To identify additional involved denitrification process B....
The powerful greenhouse gas, nitrous oxide (N2O) has a strong potential to drive climate change. Soils are the major source of N2O and microbial nitrification denitrification main processes involved. soybean endosymbiont Bradyrhizobium diazoefficiens is considered model study rhizobial denitrification, which depends on napEDABC, nirK, norCBQD, nosRZDYFLX genes. In this bacterium, role regulatory cascade FixLJ-FixK2-NnrR in expression norCBQD genes involved synthesis been previously...
Abstract The soybean endosymbiont Bradyrhizobium diazoefficiens harbours the complete denitrification pathway that is catalysed by a periplasmic nitrate reductase (Nap), copper (Cu)-containing nitrite (NirK), c-type nitric oxide (cNor), and nitrous (Nos), encoded napEDABC, nirK, norCBQD, nosRZDFYLX genes, respectively. Induction of genes requires low oxygen oxide, both signals integrated into complex regulatory network comprised two interconnected cascades, FixLJ–FixK2–NnrR RegSR–NifA....
Summary The FixK 2 protein plays a pivotal role in complex regulatory network, which controls genes for microoxic, denitrifying, and symbiotic nitrogen‐fixing lifestyles Bradyrhizobium diazoefficiens . Among the microoxic‐responsive ‐activated are fixNOQP operon, indispensable respiration symbiosis, nnrR gene needed nitric‐oxide dependent induction of norCBQD encoding denitrifying nitric oxide reductase. is CRP/FNR‐type transcription factor, recognizes 14 bp‐palindrome (FixK box) at...
Bradyrhizobium diazoefficiens can live inside soybean root nodules and in free-living conditions. In both states, when oxygen levels decrease, cells adjust their protein pools by gene transcription modulation. PhaR is a factor involved polyhydroxyalkanoate (PHA) metabolism but also plays role the microaerobic network of this bacterium. To deeply uncover function PhaR, we applied multipronged approach, including expression profile phaR mutant at transcriptional under conditions,...
Nitrous oxide (N2O) is a powerful greenhouse gas that contributes to climate change. Denitrification one of the largest sources N2O in soils. The soybean endosymbiont Bradyrhizobium diazoefficiens model for rhizobial denitrification studies since, addition fixing N2, it has ability grow anaerobically under free-living conditions by reducing nitrate from medium through complete pathway. This bacterium contains periplasmic reductase (Nap), copper (Cu)-containing nitrite (NirK), c-type nitric...
FixK2 is a CRP/FNR-type transcription factor that plays central role in sophisticated regulatory network for the anoxic, microoxic and symbiotic lifestyles of soybean endosymbiont Bradyrhizobium diazoefficiens. Aside from balanced expression fixK2 gene under conditions (induced by two-component system FixLJ negatively auto-repressed), activity posttranslationally controlled proteolysis, oxidation singular cysteine residue (C183) near its DNA-binding domain. To simulate permanent FixK2, we...
Abstract The high prevalence of antibiotic resistant bacteria (ARB) in several environments is a great concern threatening human health. Hence, it vital to dispose molecular tools that allow proper monitoring genes (ARGs) encoding resistances these important therapeutic compounds. For an accurate quantification ARGs, there need for sensitive and robust qPCR assays supported by good design primers validated protocols. In this study, eleven relevant ARGs were selected as targets, including...
Soybean (Glycine max.) is one of the most important legumes cultivated worldwide. Its productivity can be altered by some biotic and abiotic stresses like global warming, soil metal pollution or over-application herbicides paraquat (1,1’-dimethyl-4,4’-bipyridinium dichloride). In this study, effect oxidative stress produced addition (0, 20, 50 100 µM) during plant growth on symbiotic nitrogen fixation (SNF) functionality Bradyrhizobium diazoefficiens-elicited soybean nodules were evaluated....