Microwave resonator-based sensor system for specific antibody detection.

An antibody-detecting sensor is described that is based on a microwave electrodynamic resonator. A polystyrene film with immobilized bacteria deposited on a lithium niobate plate was placed at one end of the resonator and was used as the sensing element. The second end was electrically shorted. The frequency and depth of the reflection coefficient S11 for three resonances in the range 6.5-8.5 GHz were used as an analytical signal to examine antibody interactions with bacteria and determine the time required for cell immobilization. The sensor distinguished between situations in which bacteria interacted with specific antibodies and those in which no such interaction occurred (control). Although the cell-antibody interaction changed the frequency and depth of the second and third resonance peaks, the parameters of the first resonance peak did not change. The interaction of cells with nonspecific antibodies did not change the parameters of any of the peaks. These results are promising for use in the design of methods to detect specific antibodies, which can supplement the existing methods of antibody analysis.

De novo biosynthesis of 2'-fucosyllactose in a metabolically engineered Escherichia coli using a novel ɑ1,2-fucosyltransferase from Azospirillum lipoferum.

Human milk oligosaccharides are complex, indigestible oligosaccharides that provide ideal nutrition for infant development. Here, 2'-fucosyllactose was efficiently produced in Escherichia coli by using a biosynthetic pathway. For this, both lacZ and wcaJ (encoding ß-galactosidase and UDP-glucose lipid carrier transferase, respectively) were deleted to enhance the 2'-fucosyllactose biosynthesis. To further enhance 2'-fucosyllactose production, SAMT from Azospirillum lipoferum was inserted into the chromosome of the engineered strain, and the native promoter was replaced with a strong constitutive promoter (PJ23119). The titer of 2'-fucosyllactose was increased to 8.03 g/L by introducing the regulators rcsA and rcsB into the recombinant strains. Compared to wbgL-based strains, only 2'-fucosyllactose was produced in SAMT-based strains without other by-products. Finally, the highest titer of 2'-fucosyllactose reached 112.56 g/L in a 5 L bioreactor by fed-batch cultivation, with a productivity of 1.10 g/L/h and a yield of 0.98 mol/mol lactose, indicating a strong potential in industrial production.

Discovery, characterization and engineering of ligases for amide synthesis.

Coronatine and related bacterial phytotoxins are mimics of the hormone jasmonyl-L-isoleucine (JA-Ile), which mediates physiologically important plant signalling pathways1-4. Coronatine-like phytotoxins disrupt these essential pathways and have potential in the development of safer, more selective herbicides. Although the biosynthesis of coronatine has been investigated previously, the nature of the enzyme that catalyses the crucial coupling of coronafacic acid to amino acids remains unknown1,2. Here we characterize a family of enzymes, coronafacic acid ligases (CfaLs), and resolve their structures. We found that CfaL can also produce JA-Ile, despite low similarity with the Jar1 enzyme that is responsible for ligation of JA and L-Ile in plants5. This suggests that Jar1 and CfaL evolved independently to catalyse similar reactions-Jar1 producing a compound essential for plant development4,5, and the bacterial ligases producing analogues toxic to plants. We further demonstrate how CfaL enzymes can be used to synthesize a diverse array of amides, obviating the need for protecting groups. Highly selective kinetic resolutions of racemic donor or acceptor substrates were achieved, affording homochiral products. We also used structure-guided mutagenesis to engineer improved CfaL variants. Together, these results show that CfaLs can deliver a wide range of amides for agrochemical, pharmaceutical and other applications.

Identification of the rhizospheric microbe and metabolites that led by the continuous cropping of ramie (Boehmeria nivea L. Gaud).

Continuous cropping lowers the production and quality of ramie (Boehmeria nivea L. Gaud). This study aimed to reveal the metagenomic and metabolomic changes between the healthy- and obstacle-plant after a long period of continuous cropping. After 10 years of continuous cropping, ramie planted in some portions of the land exhibited weak growth and low yield (Obstacle-group), whereas, ramie planted in the other portion of the land grew healthy (Health-group). We collected rhizosphere soil and root samples from which measurements of soil chemical and plant physiochemical properties were taken. All samples were subjected to non-targeted gas chromatograph-mass spectrometer (GS/MS) metabolome analysis. Further, metagenomics was performed to analyze the functional genes in rhizospheric soil organisms. Based on the findings, ramie in Obstacle-group were characterized by shorter plant height, smaller stem diameter, and lower fiber production than that in Health-group. Besides, the Obstacle-group showed a lower relative abundance of Rhizobiaceae, Lysobacter antibioticus, and Bradyrhizobium japonicum, but a higher relative abundance of Azospirillum lipoferum and A. brasilense compared to the Health-group. Metabolomic analysis results implicated cysteinylglycine (Cys-Gly), uracil, malonate, and glycerol as the key differential metabolites between the Health- and Obstacle-group. Notably, this work revealed that bacteria such as Rhizobia potentially synthesize IAA and are likely to reduce the biotic stress of ramie. L. antibioticus also exerts a positive effect on plants in the fight against biotic stress and is mediated by metabolites including orthophosphate, uracil, and Cys-Gly, which may serve as markers for disease risk. These bacterial effects can play a key role in plant resistance to biotic stress via metabolic and methionine metabolism pathways.

Analysis of Microbial Cell Viability in a Liquid Using an Acoustic Sensor.

A method was developed for the rapid analysis and evaluation of the viability of bacteriophage-infected Escherichia coli (E.coli) XL-1 directly in a conducting suspension by using a slot-mode sensor. The method is based on recording the changes in the depth and frequency of resonant absorption peaks in the frequency dependence of the insertion loss of the sensor before and after the biologic interaction of E. coli with specific bacteriophages. The possibility was shown of recording the infection of E. coli with specific bacteriophages and assessing its viability in suspensions with a conductivity of 4.5-30 µS/cm. Сontrol experiments were carried out with non-specific interactions of E. coli cells with bacteriophages, in which no changes in the sensor variables were observed. The optimal informational variable for estimating the number of viable cells was the degree of change in the depth of the resonant peaks in the frequency dependence of the insertion loss of the sensor. The limit of cell detection was ∼102-103 cells mL-1, with an analysis time of about 5 min. An additional advantage of the sensor was the availability of a removable liquid container, which allows one to use it repeatedly and to facilitate the cleaning of the container from spent samples. The results are promising for the detection of bacteria and assessment of their viability in solutions with conductivity in the range 4.5-30 µS/cm.

Nutritional value of Sesamum indicum L. was improved by Azospirillum and Azotobacter under low input of NP fertilizers.

BACKGROUND: Sesame (Sesame indicum L.) is well-known as a versatile industrial crop having various usages and contains 50-55% oil, 20% protein, 14-20% carbohydrate and 2-3% fiber. Several environmental factors are known to adversely affect yield and productivity of sesame. Our overall aim was to improve the growth, yield and quality of sesame cv. TS-3 using plant growth promoting rhizobacteria (PGPR) and saving the nitrogen and phosphate fertilizers (NP) by 50%. Field experiment (randomized complete block design) was conducted during the months of July to October of two consecutive years 2012-2013. Azospirillum (AL) and Azotobacter (AV) were applied as seed inoculation alone as well as along with half of the recommended dose of nitrogen (N) and phosphate (P) fertilizers (urea and diammonium phosphate) at the rate of 25 kg/ha and 30 kg/ha respectively. RESULTS: Here we report that A. lipoferum along with half dose of NP fertilizers (ALCF) were highly effective in increasing the agronomic and yield traits of sesame as compared to the control. A. vinelandii plus NP fertilizers (AVCF) exhibited higher seed oil content. Minimum acid value, optimum specific gravity and modified fatty acid composition were observed in ALCF treatment. Increase in oleic acid by ALCF is directly linked with improved oil quality for health benefits as oleic acid is the fatty acid which creates a balance between saturation and unsaturation of oil and for the hypotensive (blood pressure reducing) effects. CONCLUSION: It is inferred that ALCF treatment improved plant growth, seed yield and oil quality of sesame pertaining to good quality edible oil production.

Biopriming of maize germination by the plant growth-promoting rhizobacterium Azospirillum lipoferum CRT1.

Plant growth-promoting rhizobacteria (PGPR) naturally aid plant growth, development and tolerance to stress. Yield increase by the commercial isolate Azospirillum lipoferum CRT1 was recently attributed to an enhanced sprouting success. In order to provide the first biochemical and physiological analysis of sprouting enhancement by PGPR, seed germination and metabolism were followed by time-lapse photography and GC/MS-based metabolomics, respectively, after inoculating two differentially-responding maize cultivars with A. lipoferum CRT1. Bacterial growth on the seeds and plantlet development were also determined. Bacterial inoculation of the seeds of one cultivar led to a 6-8 h hastening of radicle emergence, increased surface bacterial counts, lower contents of energetic primary metabolites before radicle emergence and increased photosynthetic yield, and root surface area, in 3-leaf plantlets. None of these changes were observed on the other maize cultivar that rather accumulated greater levels of stress-related metabolites shortly after radicle emergence. Bacterial counts and cell division-driven central root growth increased in parallel and similarly on both cultivars. A. lipoferum CRT1 stimulated pre-germinating or defense events in a cultivar-dependent manner in maize after rapid (less than 24 h) recognition with initially resting seeds. This PGPR isolate therefore bears agronomic potential as a biopriming agent.

Structural characterization and applications of a novel polysaccharide produced by Azospirillum lipoferum MTCC 2306.

Azospirillum lipoferum MTCC 2306, a free-living nitrogen fixing bacteria, has a doubling time of 1.7 h in MPSS media. At the end of 28 h at a pH of 7 and temperature of 30 °C it produces 1.8 ± 0.013 g/L biomass and 2.1 ± 0.018 g/L of cyclic beta glucan (CßG) in MPSS medium with a yield coefficient (YP/S) of 2.1. This novel polysaccharide is a water-soluble cyclic biopolymer and is generally produced by Rhizobiaceae and predominantly made up of glucose. The CßG has a degree of polymerisation varying between 10 and 13 and has both α- and ß-glycosidic linkages. It is not substituted with any functional groups such as acetates or succinates. Its ability to bind to aniline blue suggests that it can be a potential candidate for being used as carrier in medical imaging as well as in reducing toxicity of textile effluents. It is able to encapsulate rifampicin, a hydrophobic drug and increase its aqueous solubility by 71%. So, CßG appears to have promising applications in the field of drug, food, cosmetic and nutraceutical industries.

Analysis of the microbial cell-Ab binding in buffer solution by the piezoelectric resonator.

The possibility of the registration of the interaction of the cells Azospirillum lipoferum Sp59b with the specific antibodies directly in the conducting suspensions by using an acoustic sensor was shown. The main element of the sensor is a piezoelectric resonator with a lateral electric field. The analysis is based on a comparison of the resonator's electrical impedance before and after the specific biological interaction between the cells and antibodies. By using this sensor one can detect and identify the bacterial cells directly in the buffer solution with the conductivity between 2.4 and 20 µS/cm. The minimum detectable concentration of the bacterial cells turned out to be ∼103 cells/ml and for a short time (less than 10 min). Also the possibility of the detection of the cells in the presence of the extraneous microflora was shown. The results provide the opportunities for the development of a new class of the methods for the analysis of the microbial cells in real-time directly in the buffer solution.

Field-based assessment of the mechanism of maize yield enhancement by Azospirillum lipoferum CRT1.

Plant Growth-Promoting Bacteria (PGPB) of the genus Azospirillum are known to enhance root growth and yield in many plant species including cereals. To probe the underlying mechanisms, correlations between modifications of yield and 6-leaf plantlet characteristics were estimated on maize in four fields with contrasting soil properties over two consecutive years using the commercial isolate A. lipoferum CRT1. In both years, plantlet metabolome, photosynthetic potential and organ morphology were found to display field- and inoculation-specific signatures. Metabolomic analyses revealed that A. lipoferum CRT1 mostly affected sugar metabolism with no suggested impact on N and P assimilation. Mineral nitrogen feeding increased yield but did not affect yield enhancement by the bacterial partner. However, greater improvements of leaf photosynthetic potential correlated with yield diminutions and larger plantlets in all of their proportions correlated with yield enhancements. Bacterial inoculation restored proper seed-to-adult plant ratio when it accidentally dropped below 80%. Only in these cases did it raise yield. All in all, securing mature plant density is hypothesized as being the primary driver of A. lipoferum CRT1-mediated yield enhancement in maize fields.

Development and formulation of azospirillum lipoferum and pseudomonas fluorescens as effective biological agents for enhanced agro-productivity / Desenvolvimento e formulação de azospirillum lipoferum e pseudomonas fluorescens enquanto agentes biológicos eficazes para uma agro-produtividade melhorada

Biofertilizer is a group of beneficial microorganisms used for improving the productivity of soil by fixing atmospheric nitrogen or by solubilizing soil phosphorus. They also stimulate plant growth through synthesis of growth promoting substances. In this present study, Azospirillum lipoferum is grown in Nitrogen free Bromothymol blue (Nfb) medium and Pseudomonas fluorescens in King's B medium. Bioprocess condition was optimized for both of the culture and found that Pseudomonas fluorescens has shown highest growth at 300C in pH 8 after 72 hours of incubation where as Azospirillum lipoferum showed highest cell concentration at 310C in pH 7, with incubation period of 72 hours. The optimized culture is mixed with different formulations of powder and liquid carrier such as Saw dust, Rice husk, Date seed powder, Matka khad, Jiwamrit and Beejamrit respectively. Shelf life study for 0, 30, 60, 90 and 120 days by cell counting and spread plate method showed that shelf life of the biofertilizer produced from Powder and liquid carriers had high amount of viable microbial population up to 120 days storage. Among biofertilizer based bio inoculants, Saw dust showed maximum population of 77x109cfu/ml for Azospirillum lipoferum and 72 x 109 CFU/ml for Pseudomonas strain on 120th day and the liquid carrier Matka khad showed 85x109 cfu/ml for Azospirillum lipoferum and 78 x 109 CFU/ml for Pseudomonas fluorescens.

Biofertilizante é um grupo de microorganismos benéficos utilizados para melhorar a produtividade do solo através da fixação de azoto atmosférico ou por solubilização de fósforo no solo. Eles também estimulam o crescimento vegetal através de síntese de substâncias promotoras do crescimento. No presente estudo, Azospirillum lipoferum é cultivado em um meio de azul de bromotimol sem nitrogênio (Nfb) e Pseudomonas fluorescens num meio de King's B. A condição de bioprocesso foi optimizada para ambas as culturas e descobriram que Pseudomonas fluorescens mostraram maior crescimento a 300ºC em pH 8 após 72 horas de incubação, enquanto que Azospirillum lipoferum mostraram maior concentração de células a 310ºC em pH 7, com um período de incubação de 72 horas. A cultura optimizada é misturada com diferentes formulações de pó e veículo líquido tal como serragem, casca de arroz, pó de semente de tâmaras, Matka khad, Jiwamrit e Beejamrit respectivamente. O estudo do prazo de validade para 0, 30, 60, 90 e 120 dias por contagem celular e método de espalhamento em placa mostrou que o prazo de validade do biofertilizante produzido a partir do pó e veículos líquidos teve grande quantidade de população microbiana viável até 120 dias de armazenamento. Entre inoculantes biológicos de base biofertilizantes, a serragem mostrou população máxima de 77x109 CFU/ml para Azospirillum lipoferum e 72 x 109 CFU/ml para a estirpe Pseudomonas no 120º dia e um veículo líquido Matka khad mostrou 85x109 CFU/ml para Azospirillum lipoferum e 78x109 CFU/ml para Pseudomonas fluorescens.

Differential responses of Oryza sativa secondary metabolism to biotic interactions with cooperative, commensal and phytopathogenic bacteria.

MAIN CONCLUSION: Profiling of plant secondary metabolite allows to differentiate the different types of ecological interactions established between rice and bacteria. Rice responds to ecologically distinct bacteria by altering its content of flavonoids and hydroxycinnamic acid derivatives. Plants' growth and physiology are strongly influenced by the biotic interactions that plants establish with soil bacterial populations. Plants are able to sense and to respond accordingly to ecologically distinct bacteria, by inducing defense pathways against pathogens to prevent parasitic interactions, and by stimulating the growth of root-associated beneficial or commensal bacteria through root exudation. Plant secondary metabolism is expected to play a major role in this control. However, secondary metabolite responses of a same plant to cooperative, commensal and deleterious bacteria have so far never been compared. The impact of the plant growth-promoting rhizobacteria (PGPR) Azospirillum lipoferum 4B on the secondary metabolite profiles of two Oryza sativa L. cultivars (Cigalon and Nipponbare) was compared to that of a rice pathogen Burkholderia glumae AU6208, the causing agent of bacterial panicle blight and of a commensal environmental bacteria Escherichia coli B6. Root and shoot rice extracts were analyzed by reversed-phase high-performance liquid chromatography (RP-HPLC). Principal component analyses (PCAs) pinpointed discriminant secondary metabolites, which were characterized by mass spectrometry. Direct comparison of metabolic profiles evidenced that each bacterial ecological interaction induced distinct qualitative and quantitative modifications of rice secondary metabolism, by altering the content of numerous flavonoid compounds and hydroxycinnamic acid (HCA) derivatives. Secondary metabolism varied according to the cultivars and the interaction types, demonstrating the relevance of secondary metabolic profiling for studying plant-bacteria biotic interactions.

[Effect of flavonoids on the composition of surface glycopolymers in Azospirillum lipoferum Sp59b].

Cultivation of the type strain Azospirillum lipoferum Sp59b in the presence of the flavonoid quercetin induced modification of the structure of the bacterial lipopolysaccharide. Cultivation in the presence of the flavonoid was shown to result in altered serological characteristics of the bacteria, increased heterogeneity of the outer membrane lipopolysaccharide pool, as well as in modified composition and fatty acid ratio of lipid A. The flavonoid was shown to induce the synthesis of the O-specific polysaccharide with the repeating structure represented by a tetrasaccharide consisting of a linear trisaccharide fragment of α-L-Rhap residues in the main chain and the terminal ß-D-Glcp residue. The structure of this O-specific polysaccharide was identical to the previously determined structure of the capsular polysaccharide of these bacteria grown without quercetin. Modifications in the structural composition of the capsular polysaccharide induced by cultivation in the presence of quercetin were revealed.

Genome wide profiling of Azospirillum lipoferum 4B gene expression during interaction with rice roots.

Azospirillum-plant cooperation has been mainly studied from an agronomic point of view leading to a wide description of mechanisms implicated in plant growth-promoting effects. However, little is known about genetic determinants implicated in bacterial adaptation to the host plant during the transition from free-living to root-associated lifestyles. This study aims at characterizing global gene expression of Azospirillum lipoferum 4B following a 7-day-old interaction with two cultivars of Oryza sativa L. japonica (cv. Cigalon from which it was originally isolated, and cv. Nipponbare). The analysis was done on a whole genome expression array with RNA samples obtained from planktonic cells, sessile cells, and root-adhering cells. Root-associated Azospirillum cells grow in an active sessile-like state and gene expression is tightly adjusted to the host plant. Adaptation to rice seems to involve genes related to reactive oxygen species (ROS) detoxification and multidrug efflux, as well as complex regulatory networks. As revealed by the induction of genes encoding transposases, interaction with root may drive bacterial genome rearrangements. Several genes related to ABC transporters and ROS detoxification display cultivar-specific expression profiles, suggesting host specific adaptation and raising the question of A. lipoferum 4B/rice cv. Cigalon co-adaptation.

Thermostability, pH stability and dye degrading activity of a bacterial laccase are enhanced in the presence of Cu2O nanoparticles.

The present study relates to a nanotechnology enabled method in which purified laccase from Escherichia coli AKL2 was supplemented with 100 µM copper oxide nanoparticles (Cu(2)O) (NP-laccase). The activity, half life and stability of NP-laccase were enhanced by 4, 42 and 36-fold respectively at high temperature (80 °C) and also over a wide range of pH (4-12) than laccase (in the presence of 0.18 mM CuSO(4)). Thermodynamic analysis of the nanoparticle-induced enzyme stability revealed an enhanced entropy-enthalpy compensation at 80 °C, which reflected the maintenance of its native structure. This was further supported by CD studies. The enhanced activity and thermostability of NP-laccase can be utilized for efficient decolorisation of dyes (both phenolic and azo).

Effects of saline tolerant Azospirillum species on the growth parameters of mangrove seedlings.

Five species of Azospirillum isolated from Manakkudi mangrove ecosystem were subjected for their efficiency to find out their growth parameters potential for the successful establishment of mangrove seedlings. Of the isolated five Azospirillum species, Azospirillum lipoferum (60%) was found to be the dominant one. But the level of maximum indole acetic acid (IAA) production (19.8 mg.ml(-1)) and nitrogen fixation (5.9 C2H2hr1) was identified with A. brasilense. Further, A. brasilense showed significant (p < 0.05) level of increased growth parameters [maximum root length (29.55%), average root length (7.39%), total Chl (55.36%), carrotenoids (28.57%), Chl b (37.50%), carbohydrates (90.91%) and total amino acids (78.95%)] in Avicennia officinals when compared with control group. Further, A. brasilense also showed significant (p < 0.05) level of increased growth parameters [average number of primary roots (40%), average biomass (44.44%), average shoot biomass (55.56%), total Chl (20%), Chl b (77.78%) and carotenoid (1.54%)] in C. decandra seedlings when compared with control group. Similarly, the average number of primary roots (23.08%), average root biomass (15.52%), average shoot biomass (15.30%), carbohydrate (20%) and total amino acids (44.44%) were found significant (p < 0.05) in A. irakense inoculated R. apiculata seedlings. In conclusion, Azospirillum brasilense was found better for the growth of Avicennia officinalis and Ceriops decandra seedlings, but Azospirillum irakense was found better for Rhizophora apiculata seedlings.

Capsular polysaccharide of the bacterium Azospirillum lipoferum Sp59b: structure and antigenic specificity.

Antigenic differences were revealed between the cell wall outer membrane lipopolysaccharides and the capsular high molecular weight bioglycans for a typical strain of the nitrogen-fixing rhizobacterium Azospirillum lipoferum Sp59b using antibodies prepared against the homologous lipopolysaccharide and lipopolysaccharide-protein complex. From the capsular lipopolysaccharide-protein and polysaccharide-lipid complexes of A. lipoferum Sp59b, polysaccharides were isolated and their structure was for the first time established in Azospirillum by monosaccharide analysis which included determination of the absolute configurations, methylation, O-deacetylation, and one- and two-dimensional NMR spectroscopy. The polysaccharides of the capsular complexes were shown to have identical structure of the branched tetrasaccharide repeating unit, which differs from the structure of the O-specific polysaccharide within the outer membrane lipopolysaccharide of this strain.

Applicability of the 16S-23S rDNA internal spacer for PCR detection of the phytostimulatory PGPR inoculant Azospirillum lipoferum CRT1 in field soil.

AIMS: To assess the applicability of the 16S-23S rDNA internal spacer regions (ISR) as targets for PCR detection of Azospirillum ssp. and the phytostimulatory plant growth-promoting rhizobacteria seed inoculant Azospirillum lipoferum CRT1 in soil. METHODS AND RESULTS: Primer sets were designed after sequence analysis of the ISR of A. lipoferum CRT1 and Azospirillum brasilense Sp245. The primers fAZO/rAZO targeting the Azospirillum genus successfully yielded PCR amplicons (400-550 bp) from Azospirillum strains but also from certain non-Azospirillum strains in vitro, therefore they were not appropriate to monitor indigenous Azospirillum soil populations. The primers fCRT1/rCRT1 targeting A. lipoferum CRT1 generated a single 249-bp PCR product but could also amplify other strains from the same species. However, with DNA extracts from the rhizosphere of field-grown maize, both fAZO/rAZO and fCRT1/rCRT1 primer sets could be used to evidence strain CRT1 in inoculated plants by nested PCR, after a first ISR amplification with universal ribosomal primers. In soil, a 7-log dynamic range of detection (10(2)-10(8) CFU g(-1) soil) was obtained. CONCLUSIONS: The PCR primers targeting 16S-23S rDNA ISR sequences enabled detection of the inoculant A. lipoferum CRT1 in field soil. SIGNIFICANCE AND IMPACT OF THE STUDY: Convenient methods to monitor Azospirillum phytostimulators in the soil are lacking. The PCR protocols designed based on ISR sequences will be useful for detection of the crop inoculant A. lipoferum CRT1 under field conditions.

Synthesis of a tetrasaccharide related to the O-antigen from Azospirillum lipoferum SR65.

Concise synthesis of a tetrasaccharide repeating unit of the LPS isolated from Azospirillum lipoferum SR65 has been accomplished through suitable protecting group manipulations and stereoselective glycosylation starting from commercially available L-rhamnose and D-glucose. The target oligosaccharide in the form of its p-methoxyphenyl glycoside is suitable for further glycoconjugate formation via selective cleavage of the OMP glycoside. Plant growth-promoting bacteria (PGPB) of genus Azospirillum plays important roles in the growth and development of plants. The interaction between the roots of the plants and the microbes is governed by the cell surface carbohydrate polymers (CPS, LPS, etc.). The present synthetic-based study elucidates aspects of plant-microbe interaction and future biofertiliser design.