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nitrogen fixation

11033 relationships annotated with this phrase. Showing first 500 of 11033.
Source entity Relationship Target entity Species
nodulated soybean metabolic model contains 2943 nonredundant genes Glycine max; Bradyrhizobium diazoefficiens
molybdate provided to bacteroid Glycine max; Bradyrhizobium diazoefficiens
flux balance analysis optimized metabolic model Glycine max
carbon cost predictions for soybean fall within range of values observed through experimental measurements for soybean Glycine max
differentiated bacteroids were observed in nitrogen fixation zone of WT nodules Medicago truncatula
metabolic reconstruction simulates entire plant and nodule metabolism Glycine max; Bradyrhizobium diazoefficiens
whole-plant metabolic model for soybean (Glycine max) with its associated microsymbiont Bradyrhizobium diazoefficiens predicts nitrogen-fixation cost of 4.13 g C g−1 N Glycine max; Bradyrhizobium diazoefficiens
deletion of NCR343 in mutant NF-FN9363 resulted in ineffective symbiotic phenotype Medicago truncatula
Inga species have a symbiotic relationship with nitrogen-fixing bacteria
direct costs of nitrogen fixation accounts for 78% of relative growth rate difference Glycine max
flux balance analysis model yields carbon cost of symbiotic nitrogen fixation of 4.13 g C g−1 N Glycine max
carbon cost of N fixation ranged from 4.13 to 4.15 g C g − 1 N when varying the root : shoot ratio Glycine max
FBA model reconstructions have been built for Rhizobium leguminosarum Rhizobium leguminosarum
symbiotic nitrogen fixation reduces potential relative growth rate Glycine max
understanding the full cost of N fixation requires consideration of all plant and microbe metabolism for specific plant–microbe interactions
bacteroid secreted carbon dioxide Bradyrhizobium diazoefficiens
seedlings grown in soil from region lacking Bradyrhizobium were deficient in nitrogen Calicotome villosa
Inga species have symbiotic relationship with nitrogen-fixing bacteria
nlp mutants ( (ATNLP1, CPA, NLP1, AT2G27450) (NLP4, AT1G20640) ) have much higher acetylene reduction activity (ARA) Lotus japonicus
rhizobial N-fixing trees common in tropical forests can downregulate N fixation (facultative fixation)
mutants less sensitive to nitrate provide potential strategy to alleviate nitrate inhibition on symbiotic nitrogen fixation (SNF) Lotus japonicus
glnII expression in debino1 was expressed to an even higher level Medicago truncatula
15N isotopic dilution experiments showed that N2-fixing strains were able to provide up to c. 12% of the total accumulated N in maize stems Zea mays
molybdate, homocitrate, sulfate, and iron required for FeMo cofactor synthesis Bradyrhizobium diazoefficiens
amide export in the form of asparagine and glutamine increased relative growth rate Glycine max
reduced availability of iron may inhibit N2 fixation process itself
nitrogenase activity was assayed by acetylene reduction with gas chromatography
bacteroid secretes ammonium
(ATNLP1, CPA, NLP1, AT2G27450) (NLP4, AT1G20640) double mutant retains approximately 80% acetylene reduction activity (ARA) after nitrate treatment Lotus japonicus
(anac094, NAC094, AT5G39820) mutants show reduction in similar to wild-type (WT) plants Lotus japonicus
molybdate, homocitrate, sulfate, and iron required for nitrogen fixation Bradyrhizobium diazoefficiens
(ATNLP1, CPA, NLP1, AT2G27450) and (NLP4, AT1G20640) mediate downregulation of leghemoglobin (Lb) genes Lotus japonicus
amtB and glnK are activated in differentiated bacteroids when the nif gene cluster is activated Medicago truncatula
investigating plant-associated diazotrophy through the lens of correlative microscopy and chemical imaging has the potential to inform conceptual models such as mucilage-assisted N2 fixation associated with cereal crops
large metabolic variation observed between various host plant–bacteria interactions necessitates need for nodulated whole-plant models of more species
soybean yield reduction is 27% Glycine max
Inoculation of Adulam soil with Bradyrhizobium improved nitrogen accumulation of seedlings Colletia villosa
amide export resulted in relative growth rate of 0.058 g g−1 DW d−1 Glycine max
low cost of N fixation in cereals is likely similar for other cereals, with rice, sorghum, and millet all having very similar N contents to maize Oryza sativa; Sorghum bicolor; Panicum miliaceum; Zea mays
NCR peptides (ATNFS1, ATNIFS1, NFS1, NIFS1, AT5G65720) and NFS2 negatively regulate nitrogen-fixing symbiosis in M. truncatula Medicago truncatula
symbiotically fixed N is 15 N depleted
debino1 nodules do not show staining in fixation zone Medicago truncatula
optimizing an objective function such as maximizing growth in the presence of specific metabolic constraints provides global view of the metabolism of an organism under steady-state conditions
(ATNLP1, CPA, NLP1, AT2G27450) and (NLP4, AT1G20640) play essential roles in nitrate-triggered inhibition of symbiotic nitrogen fixation (SNF) efficiency in mature nodules Lotus japonicus
fix cluster genes are responsible for electron transportation to nitrogenase Medicago truncatula
carbon dioxide uptake reduction increases carbon costs of nitrogen fixation Glycine max
allantoate as nitrogen export product had no effect on relative growth rate Glycine max
malate is primary carbon source used by bacteroids Glycine max; Bradyrhizobium diazoefficiens
NCR341 could not complement the fix-phenotype of debino1 Medicago truncatula
expression levels of nif gene cluster genes were significantly suppressed in differentiated debino1 bacteroids Medicago truncatula
suppression of nif and fix cluster genes in debino1 corroborates with the analysis of the activities of nifH promoter Medicago truncatula
Their actual in situ activity has not been confirmed yet confirmation of in situ activity Oryza sativa
FBA model reconstructions have been built for Rhizobium etli Rhizobium etli
carbon cost of N fixation for the soybean FBA model is 4.13 g C g − 1 N Glycine max
symbiosis between legumes and N2-fixing bacteria (rhizobia) is main natural source of nitrogen (N) for terrestrial ecosystems
(anac094, NAC094, AT5G39820) mutants show drastic reduction in acetylene reduction activity (ARA) Lotus japonicus
debino1 mutant cannot obtain fixed nitrogen Medicago truncatula
carbon costs of nitrogen fixation for nodulated soybean estimated to be between 4.13 and 4.15 g C g−1 N Glycine max
nitrate treatment dramatically reduces acetylene reduction activity (ARA) Lotus japonicus
average/median at% 15N values across the three analysis areas did not vary Kosakonia strain DS-1
FBA model reconstructions have been built for Sinorhizobium fredii Sinorhizobium fredii
lower nodule net CO2 efflux resulted from amide export compared to ureide export Glycine max
Bosea may involve nitrogen fixation
whole-plant metabolic model for soybean (Glycine max) with its associated microsymbiont Bradyrhizobium diazoefficiens predicts cost–benefit of nitrogen fixation Glycine max; Bradyrhizobium diazoefficiens
simulations with isolated bacteroids investigate individual processes that would typically be controlled by the plant
increasing N export enables higher seed yield per plant Glycine max
actinorhizal N-fixing trees dominant in temperate and boreal biomes have obligate N fixation
previous inoculation experiments with isolated strains demonstrated the expression of nif genes in diazotrophs Oryza sativa
nitrogen-fixation cost of c. 4.13 g C g−1 N translates to grain yield reduction of 27% Glycine max
metabolic reconstruction in a tropical crop species will serve as tool to investigate key mechanisms within N-fixing symbiosis Glycine max; Bradyrhizobium diazoefficiens
bacteroid secreted water Bradyrhizobium diazoefficiens
legumes in intercropping are renowned for nitrogen-fixing capabilities
(anac094, NAC094, AT5G39820) mutants together with (ATNLP1, CPA, NLP1, AT2G27450) (NLP4, AT1G20640) mutants provide potential strategy to alleviate nitrate inhibition on symbiotic nitrogen fixation (SNF) Lotus japonicus
dinitrogen requires conversion into reactive nitrogen (Nr)
absence of site-specific 15N-fixation activities of Kosakonia strain DS-1 cells indicates at three different spots along the root Oryza sativa; Kosakonia strain DS-1
nodulated soybean predicted to have relative growth rate reduction of 28.8% to 31.5% Glycine max
nodule flux predictions were consistent with experimental evidence and analyses Glycine max
glnII expression in WT nodule fixation zone was already highly induced Medicago truncatula
metabolic reconstruction in a tropical crop species will serve as tool to investigate carbon use efficiency Glycine max; Bradyrhizobium diazoefficiens
nodule tissue is dedicated to nitrogen fixation Glycine max
nitrogen fixation is facultative Glycine max
elongated and endoreduplicated bacteroids are specialized for nitrogen fixation Medicago truncatula
NIN and (ATNSP2, NSP2, AT2G33070) are required like other symbiotic nitrogen-fixing processes
(anac094, NAC094, AT5G39820) mutants show drastic reduction in leghemoglobin (Lb) transcripts Lotus japonicus
ongoing debate on the correlation between plant growth promotion and N2 fixation activity of individual bacterial strains corroborates the lack of confirmation of in situ activity
malate provided to bacteroid Glycine max; Bradyrhizobium diazoefficiens
nodulated soybean in absence of soil nitrogen has nitrogen fixation rate of 6.8 μmol NH4 g−1 DW h−1 Glycine max
nodulated soybean shows higher profitability than fertilized soybean Glycine max
carbon cost predicted for soybean, a ureide exporter is slightly lower than 4.2 g C g − 1 N predicted using a FBA model of Medicago truncatula, an amide exporter Glycine max; Medicago truncatula
leghemoglobin (Lb) has crucial function in nitrogen fixation Lotus japonicus
FixK is involved in nitrogen fixation
symbiotic nitrogen fixation decreased relative growth rate Glycine max
legumes can establish nitrogen-fixing endosymbiotic association with soil bacteria
members of Arthrobacter and Bacillus were found to fix nitrogen and promote growth of Microcoleus vaginatus Microcoleus vaginatus
a multitude of strains commercialized as potential bio-fertilizers for crops direct evidence of bacterial N2 fixation on and within plant tissues has been missing to date direct evidence of bacterial N2 fixation on and within plant tissues
soybean growth with amide nitrogen export is predicted to be c. 5% greater than soybean growth with ureide nitrogen export Glycine max
Lotus japonicus is used as model for legume symbiotic nitrogen fixation Lotus japonicus
seedlings grown in soil from a habitat in which C. villosa is absent will be limited in nitrogen derived from N2 fixation Calicotome villosa
ammonium is assimilated by plant cells through glutamine and asparagine synthetases
fixB, fixC, and fixX had substantially reduced expression levels Medicago truncatula
Soybean (Glycine max) forms symbiosis with Bradyrhizobium diazoefficiens Glycine max; Bradyrhizobium diazoefficiens
high flux through the electron transport chain and oxidative phosphorylation supports high energy demand of N fixation Bradyrhizobium diazoefficiens
insufficient availabilities of soil micronutrients such as iron or molybdenum limit bacterial N2 fixation
Beyma nodules fixed nitrogen Lotus japonicus
bacterial strains deficient in antioxidant defense exhibit altered nitrogen-fixation capacity
low oxygen environment allows expression of enzymes of nitrogenase complex
AsE246 knockdown results in diminished nitrogen fixation activity Astragalus sinicus
mate67 mutants showed approximately 4-fold decrease in nitrogenase activity Medicago truncatula
symbiosis between Legumes and Rhizobium bacteria results in dinitrogen capture from air
host plant forms root nodules
16 molecules of ATP and 8 electrons are estimated to be required to reduce one molecule of N2 to two molecules of NH4+
nitrogen-fixing symbioses occur in root nodules
enzymes of nitrogenase complex expression enables nitrogen fixation
Tnt1 mutants of MtMATE67 show fix¯ phenotype Medicago truncatula
legume–rhizobium symbiosis is essential for nitrogen fixation
rhizobia fix nitrogen in symbiosomes Astragalus sinicus
legume family plants develop nitrogen-fixing symbioses
microaerobic environment within nodule is adjusted by leghaemoglobin
ABA application to MG-20 was associated with severe reduction in nitrogen fixation Lotus japonicus
Beyma nodule sections revealed presence of GFP-expressing bacteroids Lotus japonicus
residual nitrogenase activity in mate67 mutant nodules indicates that some rhizobia differentiate fully into bacteroids Medicago truncatula
Ljckx3 mutants have reduced nitrogen fixation Lotus japonicus
Beyma nodules contained GFP expressing bacteria Lotus japonicus
Beyma nodules were functional Lotus japonicus
Beyma mutant maintained high nitrogen fixation level Lotus japonicus
MG-20 had nitrogenase activity of 139.4 ± 32.7 C2H4 nmol plant−1 h−1
atmospheric dinitrogen (N2) is fixed by nitrogenase enzyme complex
low-oxygen concentration in infected nodule cells enables prolonged activity of oxygen-labile nitrogenase
nlp mutants ( (ATNLP1, CPA, NLP1, AT2G27450) (NLP4, AT1G20640) ) have much higher levels than wild-type (WT) plants upon nitrate supply Lotus japonicus
homocitrate provided to bacteroid Glycine max; Bradyrhizobium diazoefficiens
bacteroid secreted ammonia Bradyrhizobium diazoefficiens
nitrogen fixation costs likely to be lower for cereals
fertilization, which included iron and all other micronutrients needed for nitrogen fixation increased growth and fixation in Adulam soil Colletia villosa
Beyma had nitrogenase activity of 26.3 ± 10.4 C2H4 nmol plant−1 h−1
Burkholderia can promote plant growth through ability to fix nitrogen
Nitrogen (N)-fixing rhizobia in nodules provide distinct advantage in coping with N limitation Glycine max
legume-rhizobia symbiosis leads to formation of nodules
GmPLDα1KD mutant roots show significantly higher nitrogen-fixing activities
African legume crops can nodulate and fix nitrogen nitrogen fixation
nitrogen fixation during pod formation versus vegetative growth would be supported through increased nodule CO2 fixation
nitrogenase activity is increased in GmPLDα1KD and GmPLDα1OE nodules Glycine max
GmPLDα1OE mutant roots show significantly higher nitrogen-fixing activities
legumes form symbiotic interaction with nitrogen-fixing bacteria rhizobia
down-regulating of PEPC reduces nitrogen fixation
root nodule symbiosis is plant-microbe mutualistic interaction
oxidative stress could play a role in drought-induced inhibition of N2 fixation
nitrogen fixation by rhizobia allows farmers to be less dependent on N fertilizer application Glycine max
nodules accommodate nitrogen-fixing rhizobia
cyanobionts release to plant much of dinitrogen fixed
down-regulation of PEPC activity in nodules through antisense strategy impairs nitrogen fixation
internalization of bacteria is probably necessary for efficient provision of energy
pod formation involves newly developing nitrogen attraction throughout pod formation and pod filling
data in this report suggest that improvement of nodule capability to channel assimilates into oxaloacetate and malate formation through CO2 fixation might prolong intensive nitrogen fixation in grain legumes into the later stages of ontogeny
root nodule symbiosis is strategy for nitrogen acquisition in legume plants
P deficiency inhibits symbiotic N fixation in legumes
symbiotic root nodules host nitrogen-fixing bacteria
nodule CO2 fixation is apparently tightly bound to nitrogenase activity
increased nodule CO2 fixation supplying organic acids and carbon skeletons for nitrogen assimilation achieves more efficient nitrogen fixation
NifH modification was attempted to be identified protein modification analysis Azolla filiculoides
inhibition of N2 fixation in the nodules is associated with drought sensitivity Glycine max (L.) Merr.
(AAH, ATAAH, AT4G20070) gene expression in soybean is hypothesized to be responsible for differential sensitivities of the N2-fixation response to drought among soybean genotypes Glycine max (L.) Merr.
Pi starvation inhibits nodule nitrogenase activity Glycine max
commensals are not able to fix nitrogen
high sulphate treatment increases percentage of nitrogen derived from fixation white clover
high requirement of S for N fixation is evidenced by high nodule S concentration white clover
over-expression of (MDH, pNAD-MDH, AT3G47520) increases nodule specific activity
sulphate supply has specific effect on nitrogen fixation white clover
high sulphate treatment results in more leghaemoglobin white clover
FE protein contains high proportions of S
high mineral N supply results in increase in specific nitrogenase activity legumes
nitrogen fixation peaks during pod formation
significant amounts of sucrose resulted neither in increased specific N2-fixation activity Medicago truncatula
early bacterial death is associated with bacterial inability to fix nitrogen Medicago truncatula
S-deficiency inhibited nodulation to greater extent than N2 fixation white clover
malate known to support N2 fixation energetically
increased electron allocation to H+ avoiding excessive ammonium accumulation
pea plants demonstrate more intensive nitrogen fixation during pod formation
PEPC protein occurs alongside nitrogenase protein
biotechnological solutions that reduce environmental impacts have significant potential for yield improvements as agriculture is intensified in developing regions
relative efficiency of nitrogenase (EAC) does not differ between P-depletion and control treatments on day 5 of the experiment Medicago truncatula
absence of sulphate results in less leghaemoglobin white clover
root nodule is the site of nitrogen fixation by the rhizobia–legume symbiosis
nodule protein contents includes nitrogenase Trifolium repens L.
nodule-enhanced forms of carbonic anhydrase, phosphoenolpyruvate carboxylase (PEPC), and malate dehydrogenase (MDH, pNAD-MDH, AT3G47520) have been identified from legume nodules
root nodule symbiosis is trait limited to several plant species
phosphoenolpyruvate carboxylase (PEPC) is expressed in alfalfa nodules alfalfa nodules
NifH modification in cyanobacteria is located at 13 amino acid sequence positioned close to the active site of nitrogenase cyanobacteria
low rates of photosynthesis in Azolla cyanobiont imply that four times higher levels of FNR may be associated with high symbiotic heterocyst frequency Azolla filiculoides
nifH gene shows reduced mRNA level under severe salt stress Medicago truncatula
cyanobiont supplies plant host with nitrogen
Eurosid I clade includes higher plants known to form nitrogen-fixing root nodules
Mt-1021 Medicago truncatula plants shows less severe decrease of nifH mRNA level under severe salt stress Medicago truncatula
sulphate supply affects amount of leghaemoglobin white clover
nodulation has beneficial effect on N acquisition
nitrogen fixation effectiveness varies among African legume crops
deleterious effect of drought on alfalfa performance was targeted towards photosynthesis and nitrogenase (N ase) activity Medicago sativa
N2 fixation rates in Azolla cyanobiont increase with heterocyst frequencies Azolla filiculoides
Rhizobium mutants selected for decreased salt tolerance under free-living conditions are symbiotically deficient
nitrogenase is dependent on S supply white clover
symbiotic Hbs localize to nodules of plant roots
main isoform of Suc synthase in Lotus japonicus was recently shown to be required for nodule function Lotus japonicus
N2 fixation is sensitive to water-deficit stress Glycine max (L.) Merr.
(AAH, ATAAH, AT4G20070) mRNA levels in shoots are predicted to be inversely correlated with shoot ureide concentrations Glycine max (L.) Merr.
GmNF-YC4 overexpression significantly enhances nitrogenase activity in soybean nodules Glycine max
nitrogenase activity has high energetic demands
synthetic biology techniques cover new avenues for optimizing nitrogenase to fix atmospheric N2 in plants
nitrogenase Fe–Mo protein is low in level S-deficient nodules white clover
Fe–Mo protein contains high proportions of S
bacterial nitrogenase produces ammonia
provision of additional assimilates through sugar spraying on leaves had no effect on pea plants during vegetative growth
sulphate supply affects amount of nitrogenase Fe-Mo protein white clover
differentiated bacteria (bacteroids) fix nitrogen for host plant
capacity of nodules to fix CO2 is of crucial importance for their efficiency
cyanobacteria are filamentous, heterocystous
legume nitrogen fixation was assumed to underpin high quality of leguminous hosts for Rhinanthus minor Rhinanthus minor; legumes
cyanobacterial symbionts fix N2 in heterocysts
iron is involved in enzymatic reactions required for nitrogen fixation
(AAH, ATAAH, AT4G20070) mRNA levels in shoots are predicted to be higher in drought-tolerant versus drought-sensitive soybean genotypes Glycine max (L.) Merr.
S-deficiency on clover growth is associated with strong reduction of N2 fixation white clover
S-deficiency could increase specific nitrogenase activity expressed g−1 of nodule white clover
higher oxygen uptake per unit of fixed nitrogen and lower apparent respiratory coefficient coincides with nodules of higher specific activity and increased N2 fixation per plant
provision of additional assimilates through sugar spraying on leaves significantly improved nitrogen fixation at pod formation and pod filling
various nodule-enhanced forms of key enzymes of the biochemical pathways have been identified
nodule CO2 fixation is of central importance for efficient nitrogen fixation
differentiation in N2 fixation does not show significant further change from 2 days until end of experimental period
phosphorus (P) deficiency has negative impact on N2 fixation
smaller infected cells in RNAi (ATUPS1, UPS1, AT2G03590) plants is probably due to differences in bacteria infection, bacteroid development or endo-reduplication of the infected cells Glycine max
drought conditions has inhibitory effect on nitrogenase (N ase) activity at the nodule level Medicago sativa
Vicia faba receives nitrogen exclusively via symbiotic associations with rhizobia supplying organic nitrogen fixed from N2 Vicia faba
(AAH, ATAAH, AT4G20070) gene expression in soybean is hypothesized to determine shoot ureide concentrations during water-deficit stress Glycine max (L.) Merr.
long-term high CO2 concentrations around roots and nodules increases nodule activity
nitrate/nitrite-dependent pathway may be involved in NO synthesis in root nodules
protein regulation, metabolic adjustment, and physiological status of plants under drought is not well understood in relation to role of nitrogen fixation in nodules Medicago sativa
symbiotic associations between Azolla and nitrogen-fixing cyanobacteria have potential as natural nitrogen fertilizers Azolla
NO generation pathways are differently regulated in roots and nodules Medicago truncatula
Ljinv1 mutant bacteroids are unaffected in mutant Lotus japonicus
drought-sensitive N2-fixation genotypes (Williams, Biloxi, and KS4895) subjected to water-deficit stress exhibit reduction in nitrogenase activity Glycine max (L.) Merr.
part of scatter in relationships was associated with N-fixing species from Leguminosae and Zamiaceae
leguminous plants establish nitrogen-fixing symbioses with soil bacteria
intensive N2 fixation at pod formation was combined with lower relative efficiency of nitrogenase
sucrose synthase 2 (SuSy2) is present in root nodules Medicago truncatula
sucrose (Suc) synthase (EC 2.4.1.13) is important in root nodules
stress-induced proline accumulation occurs during symbiotic nitrogen fixation Medicago truncatula
work on biotechnological approaches for nitrogen fixation is currently underway in major projects
nitrogen retention in Azolla cyanobiont is higher percentage than reported for cyanobacteria in other symbioses Azolla filiculoides
PEPC silencing in Medicago sativa nodules resulted in strongly decreased nodule activity Medicago sativa
better nitrogen fixation per plant in +CO2 treatment is largely a result of bigger nodules with higher individual efficiency
work on biotechnological approaches for nitrogen fixation is addressing challenges of both biotechnological approaches
phosphorus depletion treatment differs significantly from control in N2 fixation per plant
Bradyrhizobium japonicum reduces (fixes) atmospheric nitrogen to nitrogen-compounds Glycine max (L.) Merr.; Bradyrhizobium japonicum
drought-sensitive N2-fixation genotypes (Williams, Biloxi, and KS4895) subjected to water-deficit stress exhibit increase in shoot ureide concentrations Glycine max (L.) Merr.
Phaseolus vulgaris plants had no nodules observed nodules Phaseolus vulgaris
yield penalty associated with increased demand on photosynthates required to support nitrogen fixation is likely to be an issue in situations where one is attempting to replace inorganic fertilizers in intensive agricultural systems in developed world
adaptations found in the Azolla cyanobiont reflect metabolism in the cyanobiont largely devoted to production of fixed nitrogen Azolla; cyanobacteria
Azolla caroliniana cyanobiont retains ~60% of nitrogen fixed Azolla caroliniana
legumes are candidates for improving soil fertility
bacterial nitrogenase catalyzes reduction of N2 Glycine max
(AAH, ATAAH, AT4G20070) mRNA levels in shoots are predicted to be differentially expressed in response to water-deficit stress Glycine max (L.) Merr.
de novo purine biosynthesis occurs in root nodules Glycine max; Phaseolus vulgaris; Vigna unguiculata
higher heterocyst frequency in Azolla cyanobiont reflects higher NifH and NifK abundance Azolla filiculoides
many new types of rhizobia are bacteria that can induce nodulation and fix nitrogen
nifK was 2.5 times more abundant in Azolla cyanobiont compared with cultured Nostoc PCC 73102 Azolla filiculoides; Nostoc PCC 73102
hormogonia lack heterocysts
sucrose synthase (SuSy) is essential for symbiotic nitrogen fixation
enhanced antioxidant enzyme activity is positively correlated with better nitrogen-fixing capacity Medicago truncatula; Sinorhizobium meliloti
lower down-regulation of nitrogenase gene nifH in Mt-RD64 plants is connected to nitrogen-fixing ability Medicago truncatula
prolonged N2 fixation confers drought tolerance Glycine max (L.) Merr.
sulfate provided to bacteroid Glycine max; Bradyrhizobium diazoefficiens
bacteroids boost competency for nitrogen fixation Medicago truncatula
NCR343 alone could complement the fix-phenotype of debino1 Medicago truncatula
rhizosphere-isolated bacterium is capable of fixing N2 in situ under gnotobiotic conditions Oryza sativa
FBA models forego assumptions used in modelling N fixation in plants
flux variability analysis performed to investigate impact of amide vs ureide export on nodule net CO2 efflux Glycine max
allantoate as nitrogen export product had little impact on carbon cost of nitrogen fixation Glycine max
fdxB expression in debino1 bacteroids was lowly expressed Medicago truncatula
amide export in the form of asparagine and glutamine reduced carbon cost of nitrogen fixation Glycine max
elevated CO2 concentration around alfalfa nodules increases nodule CO2 fixation Medicago sativa
hydroponic and aeroponic growth systems require sufficient CO2 application to roots and nodules Medicago sativa
overexpression of nodule-enhanced (MDH, pNAD-MDH, AT3G47520) (neMDH) in alfalfa nodules increased specific activity of individual nodules Medicago sativa
CO2 treatment introduction causes significant differentiation in N2 fixation of Saranac plants
nitrogen (N2) fixation in sufficient-P treatment increases steadily throughout whole experiment Medicago truncatula
Phosphorus (P) is crucial for active legume nodules
nodule development was inhibited in RNAi (ATUPS1, UPS1, AT2G03590) plants Glycine max
specific 13 amino acid sequence within NifH is close to active site of nitrogenase
group V cyanobacteria fix nitrogen only at night
(ATNLP1, CPA, NLP1, AT2G27450) or (NLP4, AT1G20640) mutants retain greater than 50% acetylene reduction activity (ARA) after nitrate treatment Lotus japonicus
nlp mutants ( (ATNLP1, CPA, NLP1, AT2G27450) (NLP4, AT1G20640) ) have much higher leghemoglobin (Lb) transcript and protein levels Lotus japonicus
NCR343-GFP and NCR343-mCherry could fully complement the fix- phenotypes of debino1 Medicago truncatula
abolishment of fix cluster genes would result in total suppression of the nitrogen fixation reaction Medicago truncatula
expression of nif and fix cluster genes in differentiated debino1 bacteroids were significantly suppressed Medicago truncatula
15N–N2 gas incubations of rice plants associated with a rhizosphere-isolated bacterium capable of colonizing rice roots and fixing N2 in situ under gnotobiotic conditions is proof of principle Oryza sativa
diazotrophic bacteria fix via nitrogenase
FBA models directly simulate fluxes through the complete metabolic network built from genome annotations
nodulated soybean metabolic model contains 2258 reactions Glycine max; Bradyrhizobium diazoefficiens
(ATHO1, GUN2, HO1, HY1, HY6, TED4, AT2G26670) mutants show decreased nitrogen fixation Lotus japonicus
nodule-specific cysteine-rich (NCR) peptides are essential for nitrogen fixation Medicago truncatula
nitrogen fixation begins in massive symbiotic cells having highly endoreduplicated chromosomes (32C/64C) Medicago truncatula
analytical approach of Gold-FISH-NanoSIMS would allow not only to eradicate doubts whether or not these xylem-associated diazotrophs are truly active in situ Zea mays
molybdate, homocitrate, sulfate, and iron required for bacteroid maintenance Bradyrhizobium diazoefficiens
rhizobia reduce atmospheric dinitrogen into ammonium
grain and forage legumes function as natural fertilizer
limited symbiotic nitrogen (N2) fixation (SNF) due to low soil Phosphate (Pi) is one of the major constraints to plant growth and chickpea productivity Cicer arietinum
malate formation is important because malate is principal source of energy for bacteroids
relative efficiency of nitrogenase (EAC) in P-depletion treatment is significantly lower than EAC at day 7 of the experiment Medicago truncatula
rhizobia convert atmospheric dinitrogen to ammonia
inoculation of soil with Bradyrhizobium isolated from root nodules of Calicotome villosa resulted in higher leaf nitrogen content Calicotome villosa
grassland studies including N-fixing species often include N-fixing species
NosR is involved in nitrogen fixation
nifH encodes nitrogenase iron protein Medicago truncatula
analytical approach of Gold-FISH-NanoSIMS could now build on these data and provide further support for in situ N2-fixation activity of xylem-associated diazotrophs Zea mays
N fixation uses 16 moles of ATP to produce 2 moles of ammonia
less optimal routes followed in reality would result in higher costs Glycine max
abiotic or biotic stress conditions impact fixation of N2
chemical reduction of nitrogen consumes large amounts of energy
carbon efficiency of nitrogen fixation can be much greater during periods of greater inner plant competition for assimilate
Saranac plants forms pink nodules
plants maintain activity of existing nodules
these measures enable upholding high N2-fixation rates well into phosphorus-depletion process Medicago truncatula
drought treatment decreased nodule respiration (R nodule) Medicago sativa
legume nitrogen fixation does not underpin quality of legumes as hosts for Rhinanthus minor Vicia faba; Rhinanthus minor
antioxidant enzyme activity is positively correlated with nitrogen-fixing capacity Medicago truncatula
plants in elevated CO2 treatment tend to develop nodules with higher %N concentration in nodules Medicago sativa
increased CO2 fixation results in better provision of organic acids for driving N2 fixation
expression of functional nitrogenase enzyme in cereal crop cells is one approach to achieve nitrogen fixation capability in cereal crops
engineered plants receiving nitrogen directly to roots would require much lower absolute amount of fixed nitrogen to mimic response to applied nitrogen
replacing nitrogen fertilizer in developed world would require levels of nitrogen fixation in cereals equivalent to those in legumes
legume plants can be cultivated without application of nitrogen fertilizers
infected cells were generally smaller in RNAi (ATUPS1, UPS1, AT2G03590) plants compared to the control plants Glycine max
yield penalties only likely to have impact with increasing levels of nitrogen fixation
day 5 of P-depletion process is when N2-fixation activity per plant diverged from fully nourished plants Medicago truncatula
nitrogen (N2) fixation in sufficient-P treatment results in approximately 4-fold increase overall Medicago truncatula
root nodules harbor symbiotic nitrogen-fixing bacteria
phosphate (Pi) supply has positive relationship with nodule performance Lupinus albus; Glycine max; Cicer arietinum; Trifolium repens; Medicago truncatula; Phaseolus vulgaris
Burkholderia phymatum forms N2-fixing nodules Burkholderia phymatum
heterocysts enable cyanobacterial symbionts to provide host with fixed nitrogen
nitrogen-compounds can be utilized by plant without need for expensive nitrogen fertilizer Glycine max (L.) Merr.
nodule CO2 fixation is pivotal for efficient nitrogen fixation Medicago sativa
strategies which enhance nodule CO2 fixation will improve nitrogen fixation
nitrogen (N2) fixation in sufficient-P treatment shows high relative efficiency at day 21 of the experiment Medicago truncatula
petiole feeding of sucrose does not increase apparent nitrogenase activity (ANA) in P-depletion treatment Medicago truncatula
Phosphorus (P) is crucial for high N2-fixation rates
this review focuses on nitrogen fixation
Insaranac plants show no measurable H2 evolution
high CO2 concentrations around nodules affects N2 fixation per plant Glycine max; Pisum sativum; Phaseolus vulgaris
nitrogenase is irreversibly denatured by oxygen
both biotechnological approaches for nitrogen fixation is unlikely that in short term any will deliver levels of fixed nitrogen equivalent to fertilizer application rates in developed world
plant growth is not limited by N2 fixation
homocitrate needs to be supplied by host to nitrogen-fixing bacteroids Medicago truncatula
altering GmINS1 expression significantly changed nitrogenase activity Glycine max
lower N2-fixation primarily restricts legume growth
nifA mutant does not fix nitrogen Sinorhizobium meliloti
elevated cytokinin in Ljein2a Ljein2b mutants may result in reduced nitrogen fixation Lotus japonicus
both biotechnological approaches for nitrogen fixation are highly challenging
P-depletion treatment maintains nitrogen (N2) fixation per plant at constant level until day 15 of the experimental period Medicago truncatula
petiole feeding of sucrose does not increase apparent nitrogenase activity (ANA) in sufficient-P treatment Medicago truncatula
lack of nitrogen fixation is responsible for death of nifA and nifH elongated bacteroids Medicago truncatula; Sinorhizobium meliloti
dinitrogen capture is followed by nitrogen fixation
overexpression of GmEXPB2 elevates plant nitrogen content Glycine max
NifH abundance was low in grasslands
earliest measurements of N-fixation costs varied greatly N-fixation cost estimates
metabolic variation across various plant and bacterial partners caused inconsistencies in N-fixation cost measurements
integration of transcriptomics and flux balance analysis (FBA) metabolic models enables analyses of all plant and microbe metabolism for specific plant–microbe interactions
nodules contains bacteria that fix nitrogen for plant
signal is nodule-localized rather than systemic Glycine max
mate67 mutant shows symbiosis-specific fix¯ phenotype Medicago truncatula
N fixed in the form of ureides was shown to be translocated from nodules
AsE246 overexpression shows no remarkable difference in nitrogenase activity Astragalus sinicus
complemented mate67 mutants produced pink wild-type-like nodules with increased nitrogenase activity Medicago truncatula
overexpression of GmEXPB2 increases nitrogenase activity Glycine max
ureide accumulation in soybean shoots has been suggested to down-regulate nodule nitrogenase activity Glycine max
increased ureide export may occur in non-stressed environments Glycine max
biochemical pathway towards malate in nodules is highlighted by fact that PEPC and (MDH, pNAD-MDH, AT3G47520) activity occur alongside nitrogenase expression and activity in emerging nodules
high N levels in the soil inhibit legume nodulation Glycine max
nodule maturation resumed upon removal of N Glycine max
atmospheric di-nitrogen (N2)-fixing bacteroids are located in root nodules Glycine max
steady low O2 supply to the bacterial microsymbionts prevents inactivation of the nitrogenase enzyme complex
RNAi (ATUPS1, UPS1, AT2G03590) plants show negatively affected nitrogen fixation Glycine max
biological nitrogen fixation is energetically expensive for bacteria
preferential translocation of Phosphate (Pi) to nodules minimizes negative effects of Phosphate (Pi) deficiency on symbiotic nitrogen (N2) fixation (SNF) capacity
decrease in nitrogen 2 (N2) fixation in droughted nodules is caused by increase in oxygen resistance that was induced in the nodule Medicago sativa
nitrogen-fixation zone comprises mature fixing cells interspersed by uninfected cells Medicago truncatula
soybean nodules is surrounded by inner, middle and outer cortex Glycine max
increased ureide export may have beneficial consequences for plant performance and seed yield Glycine max
apn1 mutants displayed severe nitrogen deficiency symptoms Lotus japonicus
introducing nitrogenase enzyme into plant organelles could create a new nitrogen-fixing capability
eukaryotes have not evolved a nitrogen-fixation capability
NifA regulates nitrogenase synthesis Sinorhizobium meliloti
signal downstream of nodule initiation causes observed alteration Glycine max
high N levels in the soil have detrimental effect on nitrogenase activity Glycine max
nodules supplied with nitrate show similar effect as high levels of ureides or related N compounds in RNAi (ATUPS1, UPS1, AT2G03590) nodules Glycine max
nifH genes were most abundant in heath
genes functioning in nitrogen fixation and metabolism showed significant enrichment among DEGs in debino1 bacteroids Medicago truncatula
Beyma nodules fixed nitrogen at lower level than MG-20 nodules Lotus japonicus
altered nitrogen metabolism pattern in debino1 corroborates with altered expression levels of nif gene cluster genes Medicago truncatula
root : shoot ratio variation between 0.09 and 0.26 has little impact on carbon costs of nitrogen fixation Glycine max
bacteroids express nitrogenase enzyme complex
amide model has larger range of carbon costs compared with ureide producing model Glycine max
root nodules create micro-aerobic conditions
efficient symbiosis requires fine coordination between legume and rhizobial metabolic processes
mutants of genes involved in nitrate transport and metabolism provide potential strategy to alleviate nitrate inhibition on symbiotic nitrogen fixation (SNF) Lotus japonicus
individual cells of Kosakonia strain DS-1 observed a varying 15N enrichment on the surface of rice roots Oryza sativa; Kosakonia strain DS-1
NifH promoter activity gradually diminishes in debino1 fixation zone Medicago truncatula
glnII mutation resulted in decreased nitrogen-fixing capacity in nodule cells Medicago truncatula
grain yield reduction of 27% compared with non-nodulating plant receiving its nitrogen from the soil Glycine max
N fixation accounts for most of energy consumed within the nodule
FdxB encodes a ferredoxin III that also transfers electrons for nitrogenase Medicago truncatula
15N2 fixation activity has been a matter of debate due to missing in situ evidence
mutant plants showed symptoms of nitrogen starvation Medicago truncatula
nitrogen-fixing symbioses allow legumes
FBA-determined cost of N fixation incorporated into Soybean-BioCro Glycine max
nifE encodes nitrogenase molybdenum-cofactor synthesis protein Medicago truncatula
15N enrichment of individual cells within each analysis area varied strongly across individual cells Kosakonia strain DS-1
a recent study identified a surprisingly high proportion of potential diazotrophs in bacterial communities associated with the stem xylem of maize plants Zea mays
nitrogenase is oxygen sensitive
carbon cost of symbiotic nitrogen fixation can be higher in ureide exporting nodules Glycine max
N-fixation cost is similar to decrease in (AXR4, RGR, RGR1, AT1G54990) predicted using a FBA model of nodulated Medicago truncatula Glycine max; Medicago truncatula
uninfected interstitial cells have novel function in nitrogen fixation Lotus japonicus
(anac094, NAC094, AT5G39820) mutants show substantial decrease in acetylene reduction activity (ARA) after nitrate supply Lotus japonicus
nitrogen fixation is being bioengineered into nonleguminous crops
current whole plant models for simulating symbiotic N fixation are limited to M. truncatula Medicago truncatula
three M. truncatula symbiotic nitrogen-fixing mutants Mtsym19, Mtsym20 and NF-FN9363 have ineffective symbiotic nodules Medicago truncatula
nodulation factors (NFs) induce nodule formation Medicago truncatula; Sinorhizobium meliloti
these models cannot capture large metabolic variation observed between various host plant–bacteria interactions
nodule plastids have novel function in nitrogen fixation Lotus japonicus
nodule produced ammonium Glycine max
(AXR4, RGR, RGR1, AT1G54990) cost of N fixation is reduced from 29% to 24% when the reference is changed from plant assimilating all of its N from ammonium to one solely using nitrate Medicago truncatula
nitrogenase enzyme complex reduces N2 to ammonia
Soybean-BioCro reduced yield by c. 27% Glycine max
(ATNLP1, CPA, NLP1, AT2G27450) and (NLP4, AT1G20640) mediate inhibition of nitrogenase activity Lotus japonicus
nitrogen fixation may explain growth promotion observed in co-culture study
inconsistencies in N-fixation cost measurements were caused by mishandling of the oxygen diffusion barrier via acetylene reduction assays, removal of nodules, or disturbing the roots
ureide export compared with amide export Glycine max
nodulated soybean FBA-BioCro model predicts value cost ratio of 10.3 to 28.1 Glycine max
collapsed central vacuoles of infected host cells are filled with starch granules Medicago truncatula
GlnII is a glutamine synthase gene required for the biological nitrogen fixation activities Medicago truncatula
nif genes in diazotrophs were presumably fixing N2 Oryza sativa
yield cost to a hypothetical N-fixing cereal is predicted to be less than half yield cost to soybean
Bradyrhizobium genus are only known N2-fixing bacteria that form viable nodules in C. villosa Colletia villosa
carbon dioxide uptake increase to 183 μmol g−1 DW h−1 results in relative growth rate equivalent to soil ammonium nutrition Glycine max
nitrogen-fixing rhizobia undergo terminal differentiation resulting in elongated and endoreduplicated bacteroids Medicago truncatula
nifH gene abundance in heath indicates that some of N needed by plants may be supplied through fixed N
NAC094-overexpressing plants (NAC-OE1 and NAC-OE2) exhibit reduced nitrogenase activity (ARA) Lotus japonicus
bacteroid RNA-Seq analysis indicates that in debino1 biological nitrogen fixation activity is impaired Medicago truncatula
carbon cost of symbiotic nitrogen fixation compared with amide exporting nodules Glycine max
nodule allantoin export reaction removed from flux balance analysis model Glycine max
FBA simulations predicted nodule must provide the bacteroid with additional protons to maximize plant growth Glycine max; Bradyrhizobium diazoefficiens
legumes may facilitate neighbors via belowground facilitation of nitrogen (N) acquisition
iron provided to bacteroid Glycine max; Bradyrhizobium diazoefficiens
soybean with nitrogen requirements equivalent to maize would have nitrogen fixation cost of 14% of relative growth rate Glycine max
30% decrease in (AXR4, RGR, RGR1, AT1G54990) was calculated based on simulations in which the plant obtains zero nitrogen from the soil Glycine max
Bosea species have been isolated from lupin root nodules
Bosea species are typically recognized as nitrogen-fixing heterotrophic bacteria associated with plants
Bacterial cells along the rhizoplane showed heterogeneous patterns of 15N enrichment Oryza sativa
elongated bacteroids surround collapsed central vacuoles of infected host cells Medicago truncatula
massive symbiotic cells have large volume vacuoles Medicago truncatula
rhizobium/legume symbiosis leads to formation of nodule
leghemoglobins are required to protect nitrogenase complex from oxygen
salt stress reduces nitrogenase activity Glycine max; Vicia faba
C. villosa is critically dependent on symbiotic N2 fixation as its main source of N Colletia villosa
bacteroids fix atmospheric nitrogen
Cloning the Rj4 gene facilitates development of molecular tools for genetic improvement of nitrogen fixation Glycine max
leguminous plants under low nitrogen conditions develop nodule
altered metabolic pathways in RNAi (ATUPS1, UPS1, AT2G03590) nodules may lead to arrest in nodule growth Glycine max
bacteria require abundant carbon supply from plant partner
shoot growth of apn1 mutants tended to be retarded relative to shoot growth of wild-type plants with compatible M. loti strains Lotus japonicus
rhizobia fix atmospheric nitrogen in root nodules
m/z 616.18 ion (heme moiety, possibly of leghemoglobin) was present at high abundance in fixation zone of nodules formed on WT/WT samples Medicago; Sinorhizobium meliloti
Medicago dnf1 mutants show complete absence of nitrogen fixation Medicago
novel matrix DMAN and conventional matrix 2,5-dihydroxybenzoic acid (DHB) were investigated for MALDI-MSI applications to study Medicago root and nodule metabolome during nitrogen fixation Medicago truncatula
metabolites of various chemical species, including amino acids, sugars, organic acids, lipids, flavonoids and their conjugates were characterized and mapped on Medicago roots and nodules Medicago truncatula
plant and bacterial mutants defective in nitrogen fixation generated valuable information for understanding of underlying mechanism of nitrogen-fixing process Medicago truncatula
Mesorhizobium ciceri CP-31-(Mc CP-31)–chickpea association shows higher symbiotic nitrogen (N2) fixation (SNF) capacity than Mesorhizobium mediterraneum SWRI9-(Mm SWRI9)–chickpea association under Pi deficiency Cicer arietinum; Mesorhizobium ciceri; Mesorhizobium mediterraneum
fixJ mutants of Sinorhizobium meliloti cannot encode nitrogenase enzyme Sinorhizobium meliloti
leghemoglobin prevents inactivation of nitrogenase
soybean forms symbiotic relationship with Rhizobium
estimations of ATP requirements for reactions occurring within a nodule give a range of 2.78–4.81 g C g−1 N
relative growth rate for nodulated soybean ranged between 0.054 and 0.056 g g−1 DW d−1 Glycine max
multiscale semi-mechanistic crop model estimates effect of N fixation on crop yield with and without soil nitrogen supply Glycine max
increased allantoin and allantoic acid levels in RNAi (ATUPS1, UPS1, AT2G03590) nodules is concurrent with decrease in N2 fixation Glycine max
legumes develop nodules
comparison of metabolite profiles and molecular ion images from nitrogen-fixing and non-fixing nodules highlighted benefits of MALDI-MSI in understanding the roles of metabolites in symbiotic nitrogen fixation Medicago
altering GmINS1 expression subsequently affected soybean nitrogen content Glycine max
50 μM ABA treatment reduces nitrogenase activity in MG-20 Lotus japonicus
respiratory activity provides nitrogenase with 16 molecules of ATP and 8 electrons
nitrogen-fixing symbioses allow thriving in nitrogen-poor soils
nitrogen-fixing symbioses diverts photoassimilate to microsymbionts
relative growth rate reduction from symbiotic nitrogen fixation integrated into crop growth model Soybean-BioCro Glycine max
rhizobia provide fixed nitrogen
symbiotic nitrogen fixation is energy-consuming energy consumption
major disruption of iron delivery to nodules results in more severe reduction of nitrogenase activity Medicago truncatula
Ljein2a Ljein2b double mutant does not show acetylene reduction activity 2 weeks after inoculation despite apparently normal nodule infection Lotus japonicus
nitrogenase proteins NifH and NifK remain relatively stable during nitrate treatment Lotus japonicus
nifX encodes iron-molybdenum cluster-binding protein Medicago truncatula
nodulated soybean in absence of soil nitrogen has relative growth rate of 0.055 g g−1 DW d−1 Glycine max
FBA simulations predicted high levels of oxygen import to the bacteroid Glycine max; Bradyrhizobium diazoefficiens
cells of first few layers of nitrogen fixation zone (ZIIId) have DNA content of 16C/32C Medicago truncatula
nitrogenase (acetylene reduction) activities per nodule fresh weight in apn1 mutants were similar to or higher than in wild-type (WT) Lotus japonicus; Mesorhizobium loti
nodules provides fixed nitrogen to domesticated crops and wild plant species
reactive oxygen species (ROS) has importance in establishing and maintaining legume–Rhizobium symbiosis
nodules from dmi2-1 roots expressing MLD point mutants are even fewer of which are pink pink nodules Medicago truncatula