A novel two-enzyme cascade one-pot synthesis of β-alanine from 1,3-diaminopropane (DAP) has been developed. In the first step, DAP was oxidized to 3-aminopropionaldehyde (3-APAL) by diamine oxidase (DAO). In the second step, 3-APAL was oxidized to β-alanine by 3-APAL dehydrogenase (APALDH). Catalase and NADH oxidase were employed to degrade the by-product, H2O2, and to regenerate the cofactor, NAD+. DAO specific to DAP has not been reported in any prokaryote. Therefore, initial proof of concept was established using commercial eukaryotic DAOpk (from porcine kidney) and catalase (from bovine liver), along with recombinant APALDH and NOX enzymes sourced from Arthrobacter crystallopoietes and Lactococcus lactis, respectively. β-Alanine was successfully produced via this pathway; 12.2 mM (1.1 g/L) was formed in 41 h with 12 % conversion. To increase the reaction rate, DAO with higher specific activity was identified from Arthrobacter pascens (DAOAp). The optimum pH and temperature of DAOAp were determined to be 9.0 and 37 °C, respectively. Batch enzymatic biotransformation achieved 6 % conversion, yielding 0.33 mM (29 mg/L) β-alanine in 4 h. The low titre in batch conversion was attributed to substrate inhibition affecting DAOAp, NOX, and catalase. Fed-batch enzymatic biotransformation was conducted to overcome substrate inhibition, yielding 47 % conversion, with 2.34 mM (63 mg/L) β-alanine formation in 4 h. Approximately a 7.5-fold increase in conversion was achieved using fed-batch enzymatic biotransformation. This study accomplished a novel two-enzyme cascade biotransformation strategy for one-pot β-alanine synthesis from DAP.
Abstract The study investigates the potential of Morus alba L. (mulberry) young and ripe fruit extracts against lung cancer cells. Cancer ranking as the second leading cause of global mortality, it is essential to investigate natural compounds like phytochemicals for therapeutic benefits. The research investigates presence of phytochemicals and antioxidant activity of both young (MAF-Y) and ripe (MAF-R) mulberry fruit extracts. Results revealed presence of various secondary metabolites, particularly high phenolic content and antioxidant properties in MAF-R. Both extracts demonstrated significant cytotoxicity against lung adenocarcinoma cells (A549), with IC50 18.4 ± 3.01µg/ml (MAF-R) and 29.41 ±3.6 µg/ml (MAF-Y). Moreover, the extracts effectively inhibited cell migration. Treatment of extracts elevated reactive oxygen species (ROS) production which resulted in disruption of mitochondrial membrane potential, and induced the process of apoptosis in lung carcinoma cells. This was evidenced through various assays including differential staining and DNA fragmentation analysis. These findings underscore the potential of mulberry fruit extracts as promising candidates for cancer prevention and treatment due to their antioxidant properties, cytotoxic effects, and ability to induce apoptosis in lung cancer cells.
Cell-free enzymatic biotransformation has been the focus of industries for the synthesis of commercially valuable biological compounds. In this study, we explored a kinetic modeling approach to study the novel, single-step, cell-free enzymatic biotransformation of 3-aminopropionaldehyde (3-Apal) to a key drug intermediate, beta-alanine. The substrate 3-Apal was converted to beta-alanine by the enzyme 3-aminopropionaldehyde dehydrogenase (APALDH), while the enzyme NADH oxidase (NOX) was deployed for cofactor recycling. The enzyme candidates were expressed in recombinant E. coli, with the specific activity of crude lysate being 5 U/mg for APALDH and 1.7 U/mg for NOX. The optimum pH and temperature were identified as pH 7 and 37 degrees C, respectively. The kinetic parameters were also estimated, as the Km values of APALDH for 3-apal and NAD+ were 0.0375 and 11.96 mM respectively, and the Km value of NOX for NADH was 0.07 mM. A kinetic model was developed by incorporating the kinetic parameters obtained from the experiment and from the available literature. With insights from the enzyme kinetics and the simulated kinetic model, the biotransformation was designed in fed-batch mode, and the conversion of 3-Apal to beta-alanine up to 15 mM was achieved within 80 min. The model was also validated with the experimental results obtained from the cell-free biotransformation. Further improvement in the yield of beta-alanine can be obtained by optimizing the initial cofactor concentration and substrate feed flow rate. Conclusively, the kinetic modeling approach can eliminate the intimidating trial experiments to achieve the maximum product yield in cell-free enzymatic biotransformation.
Secondary metabolites from medicinal plants have a well-established therapeutic potential, with many of these chemicals having specialized medical uses. Isoflavonoids, a type of secondary metabolite, have little cytotoxicity against healthy human cells, making them interesting candidates for cancer treatment. Extensive research has been conducted to investigate the chemo-preventive benefits of flavonoids in treating various cancers. Biochanin A (BA), an isoflavonoid abundant in plants such as red clover, soy, peanuts, and chickpeas, was the subject of our present study. This study aimed to determine how BA affected glucose-6-phosphate dehydrogenase (G6PD) in human lung cancer cells. The study provides meaningful insight and a significant impact of BA on the association between metastasis, inflammation, and G6PD inhibition in A549 cells. Comprehensive in vitro tests revealed that BA has anti-inflammatory effects. Molecular docking experiments shed light on BA's high binding affinity for the G6PD receptor. BA substantially decreased the expression of G6PD and other inflammatory and metastasis-related markers. In conclusion, our findings highlight the potential of BA as a therapeutic agent in cancer treatment, specifically by targeting G6PD and related pathways. BA's varied effects, which range from anti-inflammatory capabilities to metastasis reduction, make it an appealing option for future investigation in the development of new cancer therapeutics.
The alpha-Asarone-loaded on NH2-MIL-125 (AS@AMIL) was demonstrated to be exceptional potential as a chemo dynamic therapeutic agent (CDT) for lung cancer cells (A549), showing superior efficiency as compared to alpha-Asarone as well as pristine NH2-MIL-125. The loading of alpha-Asarone was achieved through cation-pi interactions between -NH3+ groups of NH2-MIL-125 and the aromatic ring of alpha-Asarone. This interaction enriches the framework of AS@AMIL with electrons enhancing the basicity of the framework (O-atoms), which substantially accelerates the decomposition of endogenous H2O2 into reactive oxygen species (ROS) to exhibit enhanced CDT activity. The AS@AMIL exhibited similar to a 1.36-fold increase in ROS production (CDT activity) compared to pristine NH2-MIL-125. The study suggests that the loading of aromatic compounds in amine-functionalized MOFs through cation-pi interactions (with -NH3+ groups) can enhance the basicity of MOFs for improved chemodynamic therapeutic activity, and such materials can also be promising as catalysts and CO2 adsorbents.
The most prevalent type of cancer found in the world is lung cancer. Furthermore, chemotherapeutic intervention for lung carcinomas is frequently associated with severe off-target effects. As a result, there is a worldwide push to investigate alternative medicines with superior tolerance profiles, such as natural compounds, to substitute routinely used chemotherapeutics. The purpose of this study is to examine the anticancer potential of aloe (S1) and coconut (S2) extract-mediated CuInS2 2 (CIS) nanoparticles against non-small cell lung carcinoma (A549) cells. S1 and S2 both efficiently showed a dose-proportionate cytotoxic effect on A549 cells, while causing negligible toxic effects on normal healthy lung cells (WI-38), indicating their safety against healthy cells. Reduced cell viability was validated by acridine orange and ethidium bromide double staining, demonstrating that apoptosis was induced in A549 cells treated with both nanoparticles. In addition, the mitochondrial membrane potential was reduced by both nanoparticles, leading to an increase in ROS generation. Both nano- particles increased caspase-3, caspase-9, and caspase-8 levels in A549 cells. To summarize, both nanoparticles induced apoptotic cell damage in A549 cells by targeting mitochondria, causing increased ROS production, activating the caspase cascade, and inducing apoptosis. Aloe (S1) and coconut (S2) extract-mediated CIS nanoparticles may represent viable therapeutic options for lung cancer management.
Silver nanoparticles (AgNPs) were prepared using a one-step reduction of silver nitrate (AgNO3) with sodium borohydride (NaBH4) in the presence of polyvinylpyrrolidone (PVP) as a capping agent. Plant extracts from D. sissoo (DS) and A. calamus L. (AC) leaves were incorporated during the synthesis process. The crystalline nature of the AgNPs was confirmed through X-ray diffraction (XRD), confirming the face-centered cubic structure, with a lattice constant of 4.08 Å and a crystallite size of 18 nm. Field Emission Gun Transmission Electron Microscopy (FEG-TEM) revealed spherical AgNPs (10–20 nm) with evident PVP adsorption, leading to size changes and agglomeration. UV–Vis spectra showed a surface plasmon resonance (SPR) band at 417 nm for AgNPs and a redshift to 420 nm for PVP-coated AgNPs, indicating successful synthesis. Fourier Transform Infrared Spectroscopy (FTIR) identified functional groups and drug-loaded samples exhibited characteristic peaks, confirming effective drug loading. The anti-cancer potential of synthesized NPs was assessed by MTT assay in human adenocarcinoma lung cancer (A549) and lung normal cells (WI-38) cells. IC50 values for all three NPs (AgPVP NPs, DS@AgPVP NPs, and AC@AgPVP NPs) were 41.60 ± 2.35, 14.25 ± 1.85, and 21.75 ± 0.498 μg/ml on A549 cells, and 420.69 ± 2.87, 408.20 ± 3.41, and 391.80 ± 1.55 μg/ml respectively. Furthermore, the NPs generated Reactive Oxygen Species (ROS) and altered the mitochondrial membrane potential (MMP). Differential staining techniques were used to investigate the apoptosis-inducing properties of the three synthesized NPs. The colony formation assay indicated that nanoparticle therapy prevented cancer cell invasion. Finally, Real-Time PCR (RT-PCR) analysis predicted the expression pattern of many apoptosis-related genes (Caspase 3, 9, and 8).
l-Pipecolic acid (Pip), a non-protein amino acid derived from lysine, plays a crucial role in regulating plant disease resistance. Ralstonia solanacearum, a bacterium that causes bacterial wilt which affects many commercially relevant plants by reducing the output as much as 90
Abstract Construction of an efficient synthetic acrylate pathway in recombinant hosts such as E. coli and lactic acid bacteria should lead to synthesis of an array of products such as propionic acid, β-alanine, α-amino butyric acid and other products. The major bottlenecks impeding the titre of propionic acid, from d-lactate via the acrylate pathway in Escherichia coli and Lactococcus lactis, mainly include regulatory hurdles, inefficiency of enzymes involved in production and inability to overexpress multiple enzymes in soluble functional form along with other factors. In this work, the three enzymes, propionyl-CoA transferase (Pct) and acryloyl-CoA reductase (Acr) from E. coli, and lactoyl-CoA dehydratase (Lcd) from Megasphaera elsdenii, that possess better kinetic parameters and reduced size, have been recruited based on the insights gained from kinetic modelling of the acrylate pathway. Secondly, a common strategy for functional expression of these pathway enzymes has been demonstrated to improve their specific activities. The expression levels of Pct, Acr and Lcd were enhanced by sorbitol-induced native folding, with exposure to heat and low expression temperature, resulting in 11-, 4- and 4-fold higher yield of soluble protein than in the control. The specific activities of Pct and Acr were 39- and 34-fold higher than Clostridium propionicum counterparts. Also, the enzyme activity of Lcd was equivalent to that in the native producer, C. propionicum. The recombinant strains exhibited 11% and 20% lesser growth rates than in the control with propionate titre of 240 mg/L and 320 mg/L when grown in glucose and d-lactate, respectively. The yields of propionic acid from glucose and lactic acid were 5% and 32%, respectively. Further improvement in yields should be achieved by expressing all the enzymes in sufficient amount and appropriate ratios, overcoming all the regulatory hurdles.
Plants have a wide range of active secondary metabolites that are frequently utilized to treat cancer. For the research, Dalbergia sissoo Roxb. ex DC. leaves (DS) were hydromethanolically extracted, and their phytochemical content was determined. Total phenolics and flavonoids were quantified along with the measurement of in vitro antioxidant and cytotoxic activities. The bioactive components in the extract were identified with the use of Gas Chromatography with High-Resolution Mass Spectrometry (GC-HRMS). The crude extract contained 177.500 +/- 0.019 mg/ml of flavonoids and 296.122 +/- 0.002 mg/ml of Gallic Acid Equivalent (GAE) phenolics. Moreover, plant crude extract showed significant 2,2-diphenyl-1-picrylhydrazyl (DPPH) activity (IC50, 14.06 +/- 0.18 mu g/ ml), 2,2 '-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) [ABTS] activity (IC50, 25.97 +/- 1.04 mu g/ml), superoxide scavenging activity (IC50, 149.91 +/- 0.39 mu g/ml), and hydrogen peroxide scavenging activity (IC50, 133.37 +/- 2.30 mu g/ml). The thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) methods were used to confirm the presence of phenolic compounds. DS effectively scavenges nitric oxide. The crude extract of DS exhibited good cytotoxic effects on lung cancer cells (A549) with an IC50 value of 90.56 +/- 2.32 (mu g/ml), and less toxicity on normal lung cells (WI-38) with an IC50 value of 381.10 +/- 1.58 (mu g/ml). IC50 value of methotrexate (the standard drug) was 10.20 +/- 1.82 mu g/ml on A549 cells and 26.21 +/- 1.14 mu g/ml on WI-38 cells. Various staining techniques [4, 6-diamidino-2-phenylindole (DAPI), Acridine orange/Ethidium Bromide (AO/ EB) staining, Giemsa staining] were used to determine the plausible mechanism of DS to induce apoptosis. The inhibiting mechanism of the crude extract was further demonstrated by the clonogenic assay and qualitative and quantitative measurements of Reactive Oxygen Species (ROS). Real-time polymerase chain reaction (RT-PCR) analysis revealed the induction of apoptosis in A549 cells through the activation of caspases 9 and 3 together with TRAIL receptors. In a nutshell, hydromethanolic extract of DS resulted in distinct apoptotic morphological alterations, ROS production, the initiation of apoptosis via activating the TRAIL receptors, caspase 9 and 3, and the suppression of colony formation in A549 cells.
Due to the presence of several active secondary metabolites, the traditional Indian and Chinese medicinal herb Acorus calamus L. has been utilized for both medical and culinary purposes since ancient times. A recent report has underscored the promising cytotoxic effect of A. calamus leaves extract against non-small cell lung cancer A549 cells. Thus, we want to separate the bioactive substance from the hydromethanolic extract of A. calamus leaves in the current investigation. Thin-layer chromatography was used to separate the compounds and different spectroscopic methods (UV, FTIR, NMR, and LCMS/MS) were used for the structure prediction. α-asarone was found to be the main bioactive compound present and it was isolated from A. calamus leaves extract. It exerted a good cytotoxic effect with an IC50 value of 21.43 ± 1.27 μM against A549 cells and IC50 value of 324.12 ± 1.32 μM against WI-38 cells. The induction of apoptosis in A549 cells by α-asarone was reaffirmed by the diverse differential staining methods including DAPI, Acridine Orange/Ethidium Bromide, and Giemsa staining. Additionally, α-asarone induced mitochondrial membrane potential (ΔΨm) dissipation with a concomitant increase in the production of ROS. Furthermore, it also increased expressions of caspase-3, caspase-9, caspase-8, DR4, and DR5 genes in A549 cells. In conclusion, α-asarone-induced apoptotic cell death in non-small lung cancer cells (A549) as a result of loss of mitochondrial function, increased ROS production, subsequent activation of an internal and extrinsic caspase pathway, and altered expression of genes controlling apoptosis. As a whole, α-asarone is a plausible therapeutic agent for managing lung cancer. HIGHLIGHTSIsolation of bioactive compound from hydromethanolic leaves extract of Acorus calamus L. by thin layer chromatography.Structural elucidation of the bioactive compound was carried out using different methods like UV analysis, FTIR, NMR, and LC-MS/MS analysis.A plausible mode of action revealed that α-asarone can induce apoptosis in lung cancer cells (A549).Communicated by Ramaswamy H. Sarma.
Organophosphates (OPs) are an integral part of modern agriculture; however, due to overexploitation, OPs pesticides residues are leaching and accumulating in the soil, and groundwater contaminated terrestrial and aquatic food webs. Acute exposure to OPs could produce toxicity in insects, plants, animals, and humans. OPs are known for covalent inhibition of acetylcholinesterase enzyme in pests and terrestrial/aquatic organisms, leading to nervous, respiratory, reproductive, and hepatic abnormalities. OPs pesticides also disrupt the growth-promoting machinery in plants by inhibiting key enzymes, permeability, and trans-cuticular diffusion, which is crucial for plant growth. Excessive use of OPs, directly/indirectly affecting human/environmental health, raise a thoughtful global concern. Developing a safe, reliable, economical, and eco-friendly methods for removing OPs pesticides from the environment is thus necessary. Bioremediation techniques coupled with microbes or microbial-biocatalysts are emerging as promising antidotes for OPs pesticides. Here, we comprehensively review the current scenario of OPs pollution, their toxicity (at a molecular level), and the recent advancements in biotechnology (modified biocatalytic systems) for detection, decontamination, and bioremediation of OP-pesticides in polluted environments. Furthermore, the review focuses on onsite applications of OPs degrading enzymes (immobilizations/biosensors/others), and it also highlights remaining challenges with future approaches.
Bacterial wilt caused by Ralstonia solanacearum has been recognized as a serious threat to tomato plants which leads to significant loss in yield in the India and across the world. However, there is less information available about the interaction of R.solanacearum and Tomato bacterial wilt. The aim of the study was to show pathogenicity of bacterial wilt in two tomato varieties one, most susceptible (GT-2) and other tolerant (GAT-5) from Anand Central Gujarat. The enzymatic activity was examined for malondialdehyde (MDA) levels, phenylalanine ammonia lyase (PAL), peroxidase (POX), catalase (CAT), superoxide dismutase (SOD). The tolerant varieties had less disease symptom as compared to the susceptible variety. During bacterial wilt pathogenesis in tomato, causes oxidative burst due to encounter of ROS. Here we report, the total amount of phenol and MDA is significantly higher in the leaves of plants inoculated with R.solanacearum of both varieties over their non-inoculated control plants. The SOD, and PAL activity were lower in tolerant varieties and reduced considerably in susceptible varieties as compared to control plants, apart from PAL, which did not demonstrate a significant decline. When compared to non-inoculated plants, CAT enzyme activity were highest in both susceptible and tolerant varieties. The results demonstrate a rapid and rigorous production of reactive oxygen in plants against bacterial wilt and reveal that both varieties of tomato plants showed significant physiological changes during interaction with the R. Solanacearum.
The effect of Lactiplantibacillus plantarum PGB02 isolated from buttermilk on serum cholesterol profile of normal and hypercholesterolemic mice was evaluated. Further changes in the expression of mice genes were determined. The hypercholesterolemia was induced in experimental mice by feeding high cholesterol and fat diet. Serum cholesterol parameters, physical parameters, cholic acid excretion, and cholesterol metabolism related gene expression analysis was carried out. L. plantarum PGB02 efficiently reduced total cholesterol, triglycerides, and LDL-cholesterol and improved HDL-cholesterol in hypercholesterolaemic mice. Body weight was reduced and fecal cholic acid increased in probiotic treatment groups. Gene expression analysis revealed that L. plantarum PGB02 up-regulated the expression of LDL receptors, CYP7A1, ABCA1, ABCG5, ABCG8, and down-regulated the expression of FXR and NPC1L1 genes. Summarizing the mechanism, L. plantarum PGB02 improved hypercholesterolemia by increasing bile acid synthesis and excretion, reducing exogeneous cholesterol absorption from the intestine, and increased LDL clearance through upregulation of LDL-receptors. The present study has given insight into the mechanism of serum cholesterol reduction by bile salt hydrolase positive L. plantarum PGB02 in mice. L. plantarum PGB02 reduced the serum cholesterol level through increased bile acid synthesis and deconjugation and reduced absorption of cholesterol in the intestine. Isolate PGB02 shown cholesterol removal potential as good as statin.
Hypercholesterolemia prevalence is increasing in most countries and it increases the risk of microvascular and cardiovascular diseases. Currently available treatments include the use of statins, fibrates, and bile acid sequesters. These treatments carry a risk of severe side effects on the host. Probiotics are well documented for their cholesterol-lowering abilities. The present study has demonstrated the screening of probiotic bacteria from buttermilk samples, their ability to deconjugate bile salts, and cholesterol-lowering ability in the media. Bile salt hydrolysis by the isolates was evaluated by direct plate assay, thin layer chromatography, and cholic acid estimation. The highest amount of cholesterol was removed in the presence of 0.3% bile. Co-precipitation of cholesterol along with cholic acid was also observed. Three isolates considered potent based on their performance through all the tests were identified by 16S- rRNA gene sequencing as PGB01- Lacticaseibacillus paracasei, PGB02- Lactiplantibacillus plantarum, and PGB05- Lacticaseibacillus paracasei subsp. tolerans.
The economic uncertainty associated with cellulosic bioethanol can be overcome through the inclusion of cheap substrates and methodologies that can extend the shelf life of cellulolytic enzymes. In this study, wild Trichoderma viride was used to produce cellulases, media formulation studies were conducted to enhance the cellulase production further and immobilization strategies were tested for stable cellulase–iron oxide magnetic nanoparticle coupling. Out of the seven different production media designed, media containing glucose, wheat bran, cellulose and corn steep liquor supported the highest biomass growth (60 Packed cell volume) and cellulase formation (7.4 U/mL), and thus was chosen for the fiscal analysis at a larger scale (1000 m3). The profitability of the cellulase production process was assessed to be 20.86%, considering both the capital expenditure and operating expenses. Further, the effect of cost of different carbon sources, nitrogen sources and cellulase yields on the annual operating costs was explored, which led to the choice of delignified sugarcane bagasse, corn steep liquor and productivity levels to be respective decisive factors of the overall cost of the cellulase production. Likewise, the break-even period of such a large-scale operation was gauged given the market price of cellulases at USD 17 for 105 U of cellulases. Moreover, enzyme immobilization led to enhanced cellulase shelf life and ultimately contributed toward saccharification cost reduction.
Developing a microbial chassis with efficient enzymes is key to the synthesis of products by metabolic engineering. The wide distribution of desired pathway enzymes across several species and categories is posing major challenges in screening and selection of the same for pathway reconstruction. One such key enzyme is isopropylmalate isomerase (IPMI) of leucine/isoleucine biosynthetic pathway. The enzymes reported earlier as citraconase and maleate hydratase in Arthrobacter sp. and Pseudomonas sp. respectively, were found to have the characteristics of IPMI. If a systematic study is undertaken to show that these orphan enzymes indeed are part of the aconitase family of enzymes, these reported ones will add to the repertoire of enzymes available for branch-chained amino acid pathway engineering. This work is focused on functional characterisation of the enzymes citraconase and maleate hydratase based on the properties of IPMI. The partially sequenced gene of maleate hydratase reported earlier served as a template to identify the respective genes in these organisms which is found to be that of IPMI with conserved regions in the active site. The native enzymes and the IPMI of A. globiformis and P. pseudoalcaligenes, expressed in E. coli acted upon all the substrates in the forward direction comprising of D-citramalate, citraconate & D-erythro-3-methylmalate. In the reverse direction all the enzymes converted citraconate to D-citramalate with high activity. The estimated equilibrium ratio was same for both the native enzyme and the over-expressed IPMI which is 96:1.5:2.5 for D-citramalate: citraconate: D-erythro-3-methylmalate. The iron requirement for both enzymes which is characteristic of IPMI is ascertained by chelation and reconstitution of the same. Therefore, this work elucidated the broad specificity and the reactions in equilibrium catalysed by these enzymes like that of IPMI, paving way for the integration of these two efficient candidates into aconitase family of enzymes facilitating pathway engineering.
Using mycorrhizal fungi with their helper bacteria (MHB) to alleviate phosphate deficiency improve plant growth and rejuvenate the soil is the newer safer and most promising environment-friendly approach to limiting synthetic agrochemicals. Here 65 MHBs were isolated from the mycorrhizosphere of the Banana plant and 12 were screened based on their biofilm formation protease and N-acyl homoserine lactones production. A newly reported MHB Enterobacter sp. was identified through the 16S ribotyping method and posed plant growth-promoting properties i.e solubilized phosphate produced indole acetic acid ammonia and hydrogen sulfide. The biocompatibility experiment showed a 4-fold increased mycorrhizal proliferation in MHB added plate compared to the control. Further field experiments suggested the banana plants 10-4-fold increment in plant height (216.54 cm) and stem diameter (10.66 cm). At the same time10-fold significant improvements were noted in leaf carbohydrate (639.9 mg g -1 ) protein (432.76 mg g -1 ) chlorophyll (268.66 mg g -1 ) phenol (1.9 mg g -1 ) and proline (uMole g -1 ) content of experimental plant compared to control. The study also showed a 5-fold increase in phosphate content (12.84 mg g -1 ) than the control (2.4 mg g -1 ). The isolates increased the mycorrhizal colonization and spore number by 79.33 % and 14.31 g -1 in the rhizospheric soil. Total organic carbon and nitrogen (0.68 %) total phosphorus (55 kg ha -1 ) and potassium (499.66 kg ha -1 ) content of soil were positively affected by MHB and AMF. Further-more principal component analysis (PCA) and Pearsons correlation analysis of all the obtained results clearly showed the positive insights of inoculated MHB and AMF on the growth of the banana plant and soil restoration.
The plant growth is influenced by multiple interactions with biotic (microbial) and abiotic components in their surroundings. These microbial interactions have both positive and negative effects on plant. Plant growth promoting bacterial (PGPR) interaction could result in positive growth under normal as well as in stress conditions. Here, we have screened two PGPR’s and determined their potential in induction of specific gene in host plant to overcome the adverse effect of biotic stress caused by Magnaporthe grisea, a fungal pathogen that cause blast in rice. We demonstrated the glucanase protein mode of action by performing comparative modeling and molecular docking of guanosine triphosphate (GTP) ligand with the protein. Besides, molecular dynamic simulations have been performed to understand the behavior of the glucanase-GTP complex. The results clearly showed that selected PGPR was better able to induce modification in host plant at morphological, biochemical, physiological and molecular level by activating the expression of β-1,3-glucanases gene in infected host plant. The docking results indicated that Tyr75, Arg256, Gly258, and Ser223 of glucanase formed four crucial hydrogen bonds with the GTP, while, only Val220 found to form hydrophobic contact with ligand. The PGPR able to induce β-1,3-glucanases gene in host plant upon pathogenic interaction and β-1,3-glucanases form complex with GTP by hydrophilic interaction for induction of defense cascade for acquiring resistance against Magnaporthe grisea.
Phosphate solubilizing bacteria (PSB) and arbuscular mycorrhiza fungi (AMF) are plant beneficial soil microorganisms that emerged as an attractive approach to replace chemical-based fertilizers. However, the role of these microbes in the combined inoculation with tricalcium phosphate (TCP) is poorly known as biofertilizers in Banana plants. The present study aim to identify PSB from the rhizospheric zone of Banana plants and investigate their growth stimulatory effect on the Banana plant after combining with AMF to alleviate the phosphate deficiency. Based on P solubilization, out of seven PSBs, one potent PSB was molecularly identified as Staphylococcus sp. strain PSB03, and also this is the first report among the reported PSB. Isolated strain PSB03 solubilized rock phosphate (RP) (tricalcium phosphate (TCP) and sodium phytate (SP)) produced indole acetic acid, ammonia, hydrogen cyanide, cell lytic enzymes and utilizes 11 different types of carbon sources. From the field (pot) study, treatment 4 (T4) (combination of PSB03 and AMF) showed the most significant effect on Banana plants. The result shows a 4 and 3-folds increment in morphological and biochemical parameters compared to uninoculated control (T1). Also, T4 shows a 5-folds high phosphate content compared to control (T1). The results demonstrated that the strain PSB03 shows rapid and high solubilization of rock phosphate (TCP and SP), had various PGP traits and was equally compatible with AMF (T4) to promote plants growth at the field level (pot-experiment). Hence, we concluded that the identified bio inoculants (T4) could be considered as a biofertilizers for sustainable Banana cultivation.