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Abbreviated scheme for the utilization of ornithine in the biosynthesis of polyamines, ornithine lipids, and the siderophore vicibactin. A portion of the arginine biosynthetic pathway from the intermediate N -acetylornithine (NAO) is shown (see also Figure 3). Abbreviations: Polyamine biosynthesis (Section ‘‘Polyamine biosynthesis and utilization’’): Adc, arginine decarboxylase; Hss, homospermidine synthase; Odc, ornithine decarboxylase; SpeB, agmatinase. Ornithine lipid biosynthesis (Section ‘‘Ornithine lipid biosynthesis and function’’): OlsA, lyso-ornithine lipid acyltransferase; OlsB, ornithine acyltransferase; OlsC and OlsE, ornithine lipid hydroxylases. S1, S2, P1 and P2 refer to structurally different species of ornithine lipids. The pathway shown is that of R. tropici CIAT899 (Vences-Guzm ́n et al., 2011) but ornithine lipids are also made by S. meliloti by a similar pathway (Gao et al., 2004). Vicibactin biosynthesis (Section ‘‘Vicibactin biosynthesis and function’’): VbsA, condensation of D-3-hydroxybutyrate with ornithine; VbsC, acetylase; VbsL, epi- merase; VbsO, ornithine hydroxylase; VbsS, non-ribosomal peptide synthase. This pathway is specific for R. leguminosarum bv. viciae (Carter et al., 2002). Other abbreviations: L -Arg, L -arginine; L -Orn, L -ornithine.
Source publication
Abstract Rhizobia are bacteria in the α-proteobacterial genera Rhizobium, Sinorhizobium, Mesorhizobium, Azorhizobium and Bradyrhizobium that reduce (fix) atmospheric nitrogen in symbiotic association with a compatible host plant. In free-living and/or symbiotically associated rhizobia, amino acids may, in addition to their incorporation into protei...
Contexts in source publication
Context 1
... are synthesized by the decarboxylation of basic amino acids by amino acid decarb- oxylases that are usually specific for one or sometimes two amino acid substrates ( Lee et al., 2007). The decarboxylation products of ornithine, arginine and lysine are putrescine, agmatine and cadaverine, respectively ( Figure 6). A given rhizobial genome will often encode several amino acid decarboxylases, usually annotated as ornithine/arginine/ lysine decarboxylases. ...
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... putatively encoding enzymes that produce other polyamines from the products of amino acid decarboxylation are also encoded in rhizobial genomes. These include agmatinase (SpeB), which hydrolyzes agmatine to putrescine and urea ( Figure 6). In S. meliloti 1021, for example, speB is contiguous with but independently transcribed from the arginine biosynthetic gene argC (Díaz et al., 2011), and speB2 (smc01967) occurs immediately downstream of a putative spermidine/putrescine ABC transport system encoded by genes smc01963!smc01966, which are homologs of potC, B, A, and D, respectively. ...
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... S. meliloti 1021 olsA (encoding lyso-ornithine lipid acyltransferase; EC 2.3.1.; Figure 6) mutant lacked ornithine lipids, but had no growth defect in phosphate-limited media and formed symbiotically effective nodules on alfalfa ( López-Lara et al., 2005;Weissenmayer et al., 2002). In Rhizobium tropici CIAT899, however, mutants deficient in hydroxylated-OL synthesis were more sensitive to acid and temperature stress, and on bean were less competitive and formed poorly developed nodules that fixed significantly less nitrogen than the wild type. ...
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... would be further metabolized by the TCA cycle. Abbreviations are as listed in Figure 6. ...
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... Barnett et al., 2004;Djordjevic, 2004 Figure 6) are induced under low iron conditions. However, inactivation of various genes in the vicibactin pathway did not result in a defective symbiosis with pea or vetch inoculated with the mutants under either iron-rich or iron-deficient conditions. ...
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This study on the nodulation and symbiotic nitrogen fixation by Acacia saligna in nine nurseries from North and South areas of Algeria indicates that Acacia saligna is mostly nodulated and fix nitrogen. Therefore, nodulation and nitrogen fixation potential were clearly superior for plants from northern nurseries than those from southern ones. Symbi...
Citations
... However, the substrates consumed by microorganisms in the fenugreek soil plots are amino acids, amines, and amides. These findings can be attributed to the fact that the consumption of amines and amides contributes to the need for nitrogen sources by rhizobium [70]. Additionally, ref [22] showed that the presence of a cover crop, mainly grass species, had some influence on soil ecology and led to soils utilizing more carbon sources than soils without cover crops. ...
In Tunisia, the olive is the most cultivated fruit crop in the northern region, where annual rainfall exceeds 400 mm. This olive-growing area is characterized by a wide coverage of marginal soil with a high slope gradient. Therefore, the inclusion of cover crops in olive orchards is a sustainable solution to enhance ecosystem productivity, improve soil fertility, and increase oil yields. This study aimed to investigate the short-term (two cropping seasons in 2021 and 2022) effects of different seeded cover crops and soil management practices on soil characteristics, as well as soil health by measuring soil enzyme activities and microbial diversity. Six cover crop types consisting of wheat, vetch, oat, fenugreek, a vetch–oat mixture, and spontaneous vegetation were tested in association with rainfed olive trees (cv. Chetoui) in the north of Tunisia and compared to a control (which was tilled periodically three times per year without intercropping). During the first cropping season, cover crops were cut as animal feed, and only residues were incorporated into the soil. However, during the second year, all cover crop biomass was incorporated into the soil. The results indicated that the dry biomass production and carbon uptake were significantly higher in grass species (wheat and oat). All of the cover crops, including the spontaneous vegetation, significantly increased soil organic matter (SOM) and macronutrient levels, mainly, available phosphorus. On the other hand, the highest level of soil nitrogen was found in the fenugreek cover crop. The soil enzyme activities in the cover crops of wheat, oat, and the vetch–oat mix were higher than those in the control. Together with the increase in soil organic matter (SOM), this demonstrates a significant improvement in soil health with cover crops. Furthermore, this study proves that the utilization of carbon sources was dominated by amides, amines, and amino acids in the fenugreek plot, while it was dominated by polymers and carboxylic acids in the case of the wheat and oat. Overall, this study demonstrates that seeding cover crops is a sustainable management practice not only to integrate livestock but also to improve soil health in semiarid olive orchards.
... However, the substrates consumed by microorganisms in the fenugreek soil plots are amino acids, amines, and amides. These findings can be attributed to the fact that the consumption of amines and amides contributes to the need for nitrogen sources by rhizobium [70]. Additionally, ref [22] showed that the presence of a cover crop, mainly grass species, had some influence on soil ecology and led to soils utilizing more carbon sources than soils without cover crops. ...
... By conducting a comparative analysis of metabolite changes in AS and EB roots, it was observed that various amino acids associated with flowering and root development exhibited differential alterations ( Figure 3). Amino acids have multiple functions, including their role as constituents of proteins, as carbon, nitrogen, or sulfur sources, as indicators of cellular nitrogen status, and as precursors of significant metabolites [39]. Leucine and arginine have been implicated in the process of root development [40,41]. ...
... The phenylalanine content exhibited a significant increase from May to June and maintained a higher level. The rapid increase in glutamic and alanine content levels was observed from EB-Aug to EB-Sep, potentially facilitating plants' flowering and fruiting processes [39]. The observation suggests that the lignification process in the root coincided with premature underground bolting. ...
The dried roots of the perennial herb Angelica sinensis (Oliv.) Diels (AS) are commonly used as medicinal and edible resources. In commercial planting, early bolting and flowering (EB) of ca. 60% in the medicine formation period reduces root yield and quality, becoming a significant bottleneck in agricultural production. In the cultivation process, summer bolting (SB) occurs from June to July, and autumn bolting (AB) occurs in September. The AB root is often mistaken for the AS root due to its similar morphological characteristics. Few studies have involved whether the root of AB could be used as herbal medicine. This study explored and compared the accumulation dynamics of primary and secondary metabolites in AS and EB roots during the vegetative growth stage (from May to September) by light microscopy, ultraviolet spectrometry, and HPLC methods. Under a microscope, the amount of free starch granules and oil chamber in the AS root increased. On the contrary, they decreased further from EB-Jul to EB-Sep. By comparison, the wall of the xylem vessel was slightly thickened and stacked, and the cell walls of parenchyma and root cortex tissue were thickened in the EB root. Early underground bolting reduces soluble sugar, soluble protein, free amino acids, total C element, total N element, ferulic acid, and ligustilide accumulation, accompanied by the lignification of the root during the vegetative growth stage. Furthermore, a total of 55 root samples from different bolting types of AS root (29 samples), SB root (14 samples), and AB root (12 samples) were collected from Gansu Province during the harvesting period (October). The later the bolting occurred, the less difference there was between unbolted and bolted roots in terms of morphological appearance and efficacy components. Fourier transform infrared spectroscopy with the attenuated total reflection mode (ATR-FTIR) provides a “holistic” spectroscopic fingerprinting of all compositions in the tested sample. The ATR-FTIR spectrum of the AB root was similar to that of the AS root. However, the number and location of absorption peaks in the spectra of SB were different, and only one strong absorption peak at 1021 cm−1 was regarded as the characteristic peak of C-O stretching vibration in lignin. The ATR-FTIR spectra can be effectively differentiated based on their various characteristics using orthogonal partial least squares discrimination analysis (OPLS-DA). Results were assessed using multiple statistical techniques, including Spearman’s correlation, principal component analysis (PCA), partial least squares discriminant analysis (PLS-DA), and OPLS-DA. Among these methods, the ATR-FTIR data demonstrated the most effective outcomes in differentiating between viable and non-viable roots for their application in herbal medicine. Essential substances are ferulic acid and flavonoid, which are much more abundant in the AB root. It provides a material basis for the pharmacological action of the AB roots and a theoretical basis for improving their availability.
... Methionine synthesis, which is provided by the host plant to the nodules, has been reported to be essential for efficient nodulation by various rhizobia (Barra et al. 2006). Tyrosine and phenylalanine are aromatic amino acid produced by the shikimate pathway which require phosphoenolpyruvate as substrate (Dunn 2014). Tyrosine is essential for the nodule formation and can be used by the bacteroid as source of carbon and nitrogen (Saha et al. 2016). ...
The study of winter stress tolerance in perennial legumes needs to consider the complete symbiotic system including both plants and bacteria since these two partners are differentially affected by stress conditions. Here, we compared the regrowth after a freezing stress of four different associations of two alfalfa populations differing in freezing tolerance (A-TF0 and A-TF7) inoculated with two Sinorhizobium (Ensifer) meliloti strains (B399 and NRG34) of contrasted adaptation to cold. To understand the contribution of each partner to a better regrowth performance of an association after freezing, we identified molecular traits having major roles in cold acclimation, freezing tolerance, and those involved in the crosstalk between alfalfa and its symbiotic partner. Regrowth after exposure to a freezing stress was 35% larger in the A-TF7 × NRG34 than in the A-TF0 × B399 association. The metabolomic study of roots, crowns and, more specifically, nodules, revealed profound changes in these organs, switching from a sink to support cold acclimation to a source of reserves enabling regrowth after deacclimation. Marked increases in concentrations of stachyose and raffinose, two sugars of the raffinose-family oligosaccharides (RFO), and in the expression level of a gene of the RFO synthetic pathway were observed in response to cold acclimation supporting the importance of a protective role for RFO in alfalfa. Both cold-adapted partners of the symbiotic association contributed to increases in arginine concentration in nodules in response to cold acclimation and deacclimation underscoring the importance of N storage and remobilization for a successful overwintering in alfalfa.
... Amino acids and biogenic amines frequently occur or are secreted by the roots and nodules of legumes (i.e., phenylethylamine and putrescine) since they are of great biological importance and considered chemo-attractants for Rhizobiales (Compton and Scharf, 2021;Fujihara, 2008;Fujihara et al., 2002;Moe, 2013). Rhizobiales demand a high quantity of amino acids for protein metabolism, carbon, nitrogen and sulfur sources, signaling status of cellular nitrogen, multiple metabolite precursors and amines (such as β-phenethylamine and putrescine necessary for growth, motility, resistance to stress, biofilm formation, among others) (Becerra-Rivera and Dunn, 2019; Compton and Scharf, 2021;Dunn, 2017;Dunn, 2015;Hidalgo-Castellanos et al., 2021;Wang et al., 2020). Therefore, the reduction of A rel of Rhizobiales as a consequence of high concentrations nZnO 2 could impact the typical functions of the alfalfa rhizosphere soil communities, similar to that observed when these taxa decrease in natural conditions (Chouhan et Soil enzymatic activity is directly related to the intrinsic characteristics of soil (i.e., type, pH, exposure time, humidity, presence of metals, among others) and the BC that inhabit it, which makes it difficult to compare experiment results among different studies even when similar concentrations of NPs have been used (García-Gómez et al., 2018;Jośko et al., 2019;Kumar et al., 2019;Kwak et al., 2017;Qian et al., 2016;Shen et al., 2015;Tondey et al., 2021;You et al., 2018). ...
Zinc peroxide nanoparticles (nZnO2) have interesting physicochemical properties for multiple industrial applications. Due to their wide use, their direct or indirect release and accumulation in soil represent a potential risk for microbial communities, among others. However, no reports have been found on their potential ecological
risks in their soil-fate environment. Thus, this study evaluates the effect of nZnO2 on taxonomic and functional diversity of bacterial communities (BC) of agriculture soil. For this purpose, the soil was exposed to three concentrations of nZnO2 (10, 100 and 1000 mg/kg of soil) in microcosms that were evaluated after 15 and 30 days. The taxonomic and functional diversity of the BC was determined using amplicon sequencing (16S rRNA), physiological profiles (CLPP) and enzymatic activity. Exposure to low concentrations of nZnO2 (up to 100 mg/kg soil) on days 15 and 30 led to an increase of taxonomic diversity, while at 1000 mg/kg nZnO2, taxonomic and functional diversity were reduced in both exposure times. At day 30 (1000 mg/kg nZnO2), a significant impact on taxonomic diversity was manifested by (i) reduction in relative abundance of approximately 40 taxonomic groups, mainly from Rhizobiales, Azospirillales (Pseudomonadota, synonym: Proteobacteria) and increase in relative abundance of Lachnospirales (Bacillota, synonym: Firmicutes), Bacteroidales (Bacteroidota, synomym: Bacteroidetes) and others; (ii) reduction in metabolism of amino acids and amines/amides; and (iii) increase in dehydrogenase and urease activities with respect to the controls. These findings may indicate that the accumulation of large concentrations of nZnO2 in soil would negatively affect the soil biological functions, due to changes in the taxonomic and functional diversity of its BC, whereas low concentrations would likely promote them.
... Amino acids, as well as their incorporation into proteins, serve as precursors of various metabolites, sources of nitrogen, carbon and sulfur, and signals of cellular nitrogen status in both free-living rhizobia and symbiotic bacteroids (Dunn 2015). In free-living rhizobia, many amino acids are required for the growth (Becker et al. 2004). ...
... When rhizobia differentiated into bacteroids, biosynthesis of most amino acids is down-regulated, and they are obtained largely from the host during SNF (Day et al. 2001). In addition, the process of symbiotic nitrogen fixing is accompanied by a severe reduction in ammonia assimilation into amino acids, allowing the export of ammonia to the host (Dunn 2015). Interestingly, specific amino acids needed for microaerobic metabolism and nitrogen fixation are synthesized in large quantities by de novo or by protein/amino acid turnover in nitrogen-fixing bacteroids (Vercruysse et al. 2011). ...
Symbiotic nitrogen fixation (SNF) by rhizobium, a Gram-negative soil bacterium, is an essential component in the nitrogen cycle and is a sustainable green way to maintain soil fertility without chemical energy consumption. SNF, which results from the processes of nodulation, rhizobial infection, bacteroid differentiation and nitrogen-fixing reaction, requires the expression of various genes from both symbionts with adaptation to the changing environment. To achieve successful nitrogen fixation, rhizobia and their hosts cooperate closely for precise regulation of symbiotic genes, metabolic processes and internal environment homeostasis. Many researches have progressed to reveal the ample information about regulatory aspects of SNF during recent decades, but the major bottlenecks regarding improvement of nitrogen-fixing efficiency has proven to be complex. In this mini-review, we summarize recent advances that have contributed to understanding the rhizobial regulatory aspects that determine SNF efficiency, focusing on the coordinated regulatory mechanism of symbiotic genes, oxygen, carbon metabolism, amino acid metabolism, combined nitrogen, non-coding RNAs and internal environment homeostasis. Unraveling regulatory determinants of SNF in the nitrogen-fixing protagonist rhizobium is expected to promote an improvement of nitrogen-fixing efficiency in crop production.
... After absorbing by root systems, they can be used as precursors for new amino acids and proteins required by plants, and participate in the synthesis of organic compounds such as sugars and lipids through the tricarboxylic acid cycle. 41,42 However, there were notable differences in the type and content of free amino acids in AAFs prepared from different raw materials. [15][16][17] Different amino acids have different physiological effects on plants, and this leads to the functional diversity of AAFs. ...
BACKGROUND
There is currently an increase in the use of new types of fertilizers in modern agriculture. Studies have shown that amino acid fertilizers can improve crop yield and quality. However, their effects on crop rhizosphere ecology and their ecological impacts on crop yield are largely unknown. This study evaluated the effects of a water‐soluble amino acid fertilizer (WAAF) on tomatoes and its ecological effects on rhizosphere bacterial communities using greenhouse pot experiments.
RESULTS
The results showed that WAAF could promote the growth of tomatoes and improve the quality of fruits more effectively than water‐soluble chemical fertilizer controls. Interestingly, WAAF showed a different regulating pattern on root exudates and increased the secretion of 17 major water‐soluble root exudates, including hexadecanoic acid and 3‐hydroxy‐γ‐butyrolactone. Water‐soluble amino acid fertilizer also affected noticeably the composition, abundance, and beta‐diversity of rhizosphere bacterial communities, and strengthened the potential relationships between community members. Water‐soluble amino acid fertilizer showed a significant selective enrichment ability and recruited some members of the genera such as Cupriavidus, Ralstonia, Chitinophaga, Gemmatimonas, Mitsuaria, Mucilaginibacter, Paracoccus, Sphingopyxis, and Variovorax. Network analysis and functional prediction implied that, besides fertilizer effects, the recruiting of beneficial microbes involved in chemotaxis and biofilm formation was also a considerable factor in tomato yield and quality improvement.
CONCLUSION
Our study revealed ecological and recruiting effects of WAAF on rhizosphere microbes and potentially beneficial microbiota, and provided a basis for the amino acid fertilizer regulation of rhizosphere ecology to improve soil health and further improve crop yield and quality. © 2023 Society of Chemical Industry.
... These pathways are mostly legume-diazotroph interaction-specific and needed for the legume seedlings to get activated during the initiation of the symbiotic association. Glutathione metabolism-related pathway is related to ROS-scavenging during diazotrophic interaction and nodulation (Mandon et al., 2021); amino acid metabolism (biosynthesis, transport, and/or degradation) and are often crucial for the establishment and maintenance of an effective nitrogen-fixing symbiosis process, which is intimately interconnected with the metabolism of the plant (Dunn, 2014); nitrogen signaling and metabolism (Carvalho et al., 2014); and symbiosome-related pathways (phagosome). It is reported that the root cells accommodate the rhizobia by the suppression and defunctionalization of their vacuole and also by retargeting some tonoplast proteins to symbiosome (Gavrin et al., 2014). ...
Understanding the beneficial plant–microbe interactions is becoming extremely critical for deploying microbes imparting plant fitness and achieving sustainability in agriculture. Diazotrophic bacteria have the unique ability to survive without external sources of nitrogen and simultaneously promote host plant growth, but the mechanisms of endophytic interaction in cereals and legumes have not been studied extensively. We have studied the early interaction of two diazotrophic bacteria, Gluconacetobacter diazotrophicus (GAB) and Bradyrhizobium japonicum (BRH), in 15-day-old seedlings of rice and soybean up to 120 h after inoculation (hai) under low-nitrogen medium. Root colonization of GAB in rice was higher than that of BRH, and BRH colonization was higher in soybean roots as observed from the scanning electron microscopy at 120 hai. Peroxidase enzyme was significantly higher at 24 hai but thereafter was reduced sharply in soybean and gradually in rice. The roots of rice and soybean inoculated with GAB and BRH harvested from five time points were pooled, and transcriptome analysis was executed along with control. Two pathways, “Plant pathogen interaction” and “MAPK signaling,” were specific to Rice-Gluconacetobacter (RG), whereas the pathways related to nitrogen metabolism and plant hormone signaling were specific to Rice-Bradyrhizobium (RB) in rice. Comparative transcriptome analysis of the root tissues revealed that several plant–diazotroph-specific differentially expressed genes (DEGs) and metabolic pathways of plant–diazotroph-specific transcripts, viz., chitinase, brassinosteroid, auxin, Myeloblastosis (MYB), nodulin, and nitrate transporter (NRT), were common in all plant–diazotroph combinations; three transcripts, viz., nitrate transport accessory protein (NAR), thaumatin, and thionin, were exclusive in rice and another three transcripts, viz., NAC (NAM: no apical meristem, ATAF: Arabidopsis thaliana activating factor, and CUC: cup-shaped cotyledon), ABA (abscisic acid), and ammonium transporter, were exclusive in soybean. Differential expression of these transcripts and reduction in pathogenesis-related (PR) protein expression show the early interaction. Based on the interaction, it can be inferred that the compatibility of rice and soybean is more with GAB and BRH, respectively. We propose that rice is unable to identify the diazotroph as a beneficial microorganism or a pathogen from an early response. So, it expressed the hypersensitivity-related transcripts along with PR proteins. The molecular mechanism of diazotrophic associations of GAB and BRH with rice vis-à-vis soybean will shed light on the basic understanding of host responses to beneficial microorganisms.
... The BJS_08261 protein was identified as an oxidoreductase enzyme, a succinate-semialdehyde dehydrogenase (GabD protein, EC 1.2.1.24) involved in the GABA (γ-aminobutyric acid) metabolism [81]. When R. leguminosarum bv. ...
Background
Bradyrhizobium japonicum strain SEMIA 5079 (= CPAC 15) is a nitrogen-fixing symbiont of soybean broadly used in commercial inoculants in Brazil. Its genome has about 50% of hypothetical (HP) protein-coding genes, many in the symbiosis island, raising questions about their putative role on the biological nitrogen fixation (BNF) process. This study aimed to infer functional roles to 15 HP genes localized in the symbiosis island of SEMIA 5079, and to analyze their expression in the presence of a nod -gene inducer.
Results
A workflow of bioinformatics tools/databases was established and allowed the functional annotation of the HP genes. Most were enzymes, including transferases in the biosynthetic pathways of cobalamin, amino acids and secondary metabolites that may help in saprophytic ability and stress tolerance, and hydrolases, that may be important for competitiveness, plant infection, and stress tolerance. Putative roles for other enzymes and transporters identified are discussed. Some HP proteins were specific to the genus Bradyrhizobium , others to specific host legumes, and the analysis of orthologues helped to predict roles in BNF.
Conclusions
All 15 HP genes were induced by genistein and high induction was confirmed in five of them, suggesting major roles in the BNF process.
... Rhizobia-legume symbiosis is also one of the beststudied for the signal exchange process mediated through the flavonoids (secondary metabolites) released by the legume root [19]. Further, the primary metabolites in the RE serve as carbon, nitrogen, or sulfur sources for free-living and/or symbiotically associated rhizobia [20]. Thus, the role of primary metabolites in the RE of legume-cereal intercrop in the epiphytic interactions of rhizobia needs to be characterized. ...
Legume-cereal intercropping systems, in the context of diversity, ecological function, and better yield have been widely studied. Such systems enhance nutrient phytoavailability by balancing root-rhizosphere interactions. Root exudates (RE) play an important role in the rhizospheric interactions of plant-plant and/or plant-microbiome interaction. However, the influence of the primary metabolites of RE on plant-rhizobia interactions in a legume-cereal intercrop system is not known. To understand the plant communication with rhizobia, Cajanus cajan-Zea mays intercropped plants and the broad host range legume nodulating Ensifer fredii NGR234 as the model plants and rhizobium used respectively. A metabolomics-based approach revealed a clear separation between intercropped and monocropped RE of the two plants. Intercropped C. cajan showed an increase in the myo-inositol, and proline, while intercropped Z. mays showed enhanced galactose, D-glucopyranoside, and arginine in the RE. Physiological assays of NGR234 with the RE of intercropped C. cajan exhibited a significant enhancement in biofilm formation, while intercropped Z. mays RE accelerated the bacterial growth in the late log phase. Further, using label-free proteomics, we identified a total of 2570 proteins of NGR234 covering 50% annotated protein sequences upon exposure to Z. mays RE. Furthermore, intercropped Z. mays RE upregulated bacterioferritin comigratory protein (BCP), putative nitroreductase, IlvD, LeuC, D (branched-chain amino acid proteins), and chaperonin proteins GroEL2. Identification offered new insights into the metabolome of the legume-cereal intercrop and proteome of NGR234-Z. mays interactions that underline the new molecular candidates likely to be involved in the fitness of rhizobium in the intercropping system.
