Rajni Singh

Chickpea (Cicer arietinum L.) is a vital legume crop, but its productivity is often limited by poor soil fertility. This study aimed to assess the nodulation efficacy and plant growth-enhancing activities of six Mesorhizobium spp. strains in the chickpea cultivar Pusa 362 through the Leonard jar experiment and field trial. The strains, including two strains from ICRISAT (reference strains), were tested for solubilization of phosphate, potassium, and zinc, and production of Indole-3-Acetic Acid (IAA). Strain C5 excelled in phosphate solubilization (61.40 µg/ml), while C7 was superior in potassium (26.10 µg/ml) and zinc phosphate (69.15 µg/ml) solubilization; C17 showed the highest IAA production (25.75 µg/ml). In the Leonard jar experiment, inoculation of strains M. ciceri C5 and M. helmanticense C17 exhibited the highest nodule number and root dry weight, while treatments with M. ciceri C5 and M. helmanticense C7 inoculation recorded the maximum nodule dry weight and shoot dry weight. Field trials indicated significant improvements in nodulation, biomass, and nitrogen content in chickpeas inoculated with these strains. Treatment with strain C7 led to the highest increase in nodule number and root dry weight over the control, while strain C5 inoculation recorded maximum grain yield. Correlation analysis showed positive relationships between yield and several growth parameters. Nodule occupancy tests revealed that strain C7 had the highest occupancy (32.98%), followed by C5 (31.92%), indicating superior nodulation competitiveness under field conditions. These results suggest that inoculation with specific Mesorhizobium strains can significantly enhance chickpea productivity through improved nodulation and nitrogen fixation.

Antibiotic resistance poses the biggest threats to global health and development and also to food security. β-lactam antibiotics (BLAs) responsible for the transpeptidation/cross-linking process during cell wall biosynthesis contribute to the maximum resistance. The production of β-lactamase enzyme is a significant contributing factor to the development of antibiotic resistance to β-lactam antibiotics. Unintentional disposal of antibiotics from the manufacturing units of pharma industries to the water bodies enhances the exposure of antibiotics, contributing to resistance. This study describes the presence of > 50 antibiotic-resistant bacterial strains in pharma effluent of Himachal Pradesh, India. Among 54 isolates, 40% showed ampicillin resistance above 100 µg/mL, 13% showed resistance above 5000 µg/mL, and 3 strains showed resistance at 15,000 µg/mL of ampicillin. Enterobacter hormaechei RSM5 showed the highest minimum inhibitory concentration (MIC) and cell viability and was selected for further studies. It produces lactamase (0.24 U/mL) to resist the higher concentration of antibiotics present in the media/effluent and demonstrated resistance against 3 different classes of antibiotics, confirming its status as a multidrug resistance (MDR) strain. The high-performance liquid chromatography (HPLC) analysis of the isolate demonstrated that Enterobacter hormaechei RSM5 can degrade ampicillin within 24 h of incubation in medium/effluent. The emergence of Enterobacter as a pathogen with antibiotic resistance poses a significant health concern that could also be explored for the removal of antibiotics from the effluent at the source. The future of research in this area needs to be open and mindful of new approaches.

Chickpea is a crucial leguminous crop and India is the leading producer, with an average yield of 1.18 tons/ha. It is renowned for its specific nodulation with rhizobia. Despite its significance, studies on chickpea-nodulating rhizobia often focused on small-scale investigations within restricted geographical areas. This study delves into the population, genetic diversity, and symbiotic efficiency of chickpea-nodulating rhizobia in the Indo-Gangetic Plains (IGP) of India. The study revealed a low population of chickpea rhizobia (ranging from 11 to 565 cells/g dry soil) across the examined area. Only three samples exhibited a population exceeding 300 cells/g, emphasizing the potential need for inoculation of rhizobia with efficient and competitive strains. Correlation analysis highlighted a significant positive correlation between rhizobial population and organic carbon content, among various soil parameters like pH, electrical conductivity, available nitrogen (N), phosphorus (P), potassium (K), and organic carbon content. Among the 79 presumptive rhizobia isolated from 24 IGP locations, 61 successfully nodulated chickpea cultivar Pusa 362. 16S rRNA gene sequencing categorized 54 isolates as Mesorhizobium, four as Rhizobium, and three as Ensifer. Genetic diversity assessed by BOX-PCR revealed sixteen distinct banding patterns, underscoring substantial variability among the strains. The strains exhibited plant growth-promoting activities, salt tolerance up to 3% NaCl, and pH tolerance between 4 and 10. Six symbiotically efficient strains were identified based on their positive impact on nodulation and dry biomass. This study provides crucial insights into the diversity, genetic makeup, and symbiotic efficiency of chickpea rhizobia in the IGP, supporting the potential use of indigenous rhizobia for sustainable chickpea productivity in the region.

In the present study, ten (10) selected bacteria isolated from chasmophytic wild Chenopodium were evaluated for alleviation of drought stress in chickpea. All the bacterial cultures were potential P, K and Zn solubilizer. About 50% of the bacteria could produce Indole-3-acetic acid (IAA) and 1-aminocyclopropane-1-carboxylate (ACC) deaminase. The bacteria showed wide range of tolerance towards pH, salinity, temperature and osmotic stress. Bacillus paralicheniformis L38, Pseudomonas sp. LN75, Enterobacter hormachei subsp. xiangfengensis LJ89, B. paramycoides L17 and Micrococcus luteus LA9 significantly improved growth and nutrient (N, P, K, Fe and Zn) content in chickpea under water stress during a green house experiment conducted following a completely randomized design (CRD). Application of Microbacterium imperiale LJ10, B. stercoris LN74, Pseudomonas sp. LN75, B. paralicheniformis L38 and E. hormachei subsp. xiangfengensis LJ89 reduced the antioxidant enzymes under water stress. During field experiments conducted following randomized block design (RBD), all the bacterial inoculations improved chickpea yield under water stress. Highest yield (1363 kg ha⁻¹) was obtained in plants inoculated with Pseudomonas sp. LN75. Pseudomonas sp. LN75, B. paralicheniformis L38 and E. hormachei subsp. xiangfengensis LJ89 have potential as microbial stimulants to alleviate the water stress in chickpea. To the best of our knowledge this is the first report of using chasmophyte associated bacteria for alleviation of water stress in a crop plant.

Blood clot formation in blood vessels (thrombosis) is a major cause of life-threatening cardiovascular diseases. These clots are formed by αA-, βB-, and ϒ-peptide chains of fibrinogen joined together by isopeptide bonds with the help of blood coagulation factor XIIIa. These clot structures are altered by various factors such as thrombin, platelets, transglutaminase, DNA, histones, and red blood cells. Various factors are used to dissolve the blood clot, such as anticoagulant agents, antiplatelets drugs, fibrinolytic enzymes, and surgical operations. Fibrinolytic enzymes are produced by microorganisms (bacteria, fungi, etc.): streptokinase of Streptococcus hemolyticus, nattokinase of Bacillus subtilis YF 38, bafibrinase of Bacillus sp. AS-S20-I, longolytin of Arthrobotrys longa, versiase of Aspergillus versicolor ZLH-1, etc. They act as a thrombolytic agent by either enhancing the production of plasminogen activators (tissue or urokinase types), which convert inactive plasminogen to active plasmin, or acting as plasmin-like proteins themselves, forming fibrin degradation products which cause normal blood flow again in blood vessels. Fibrinolytic enzymes may be classified in two groups, as serine proteases and metalloproteases, based on their catalytic properties, consisting of a catalytic triad responsible for their fibrinolytic activity having different physiochemical properties (such as molecular weight, pH, and temperature). The analysis of fibrinolysis helps to detect hyperfibrinolysis (menorrhagia, renal failure, etc.) and hypofibrinolysis (diabetes, obesity, etc.) with the help of various fibrinolytic assays such as a fibrin plate assay, fibrin microplate assay, the viscoelastic method, etc. These fibrinolytic activities serve as a key aspect in the recognition of numerous cardiovascular diseases and can be easily produced on a large scale with a short generation time by microbes and are less expensive.

Enterobacter cloacae RSC3 isolated from an industrial pesticide site transformed arsenate into arsenite. The arsenate is transported by membrane-bound phosphate transporter and transformed to arsenite by arsenate reductase (arsC). E. cloacae RSC3 produced an arsenate reductase enzyme with a maximum activity of 354 U after 72 h of incubation. Arsenate reductase was found to be active and stable at a wide range of temperatures (20 and 45 °C) and pH (5–10), with maximum activity at 35 °C and pH 7.0. The arsenate reductase protein was further characterised molecularly using different bioinformatics tools. The 3D structure of ArsC protein was predicted by homology modelling and validated by the Ramachandran plot with 91.9% residues in the most favoured region. ArsC protein of E. cloacae RSC3 revealed structural homology with ArsC from PDB ID: 1S3C. The gene ontology results also showed that the ArsC protein had a molecular functionality of the arsenate reductase (glutaredoxin) activity and the biological function of cellular response to DNA damage stimulus. Molecular docking analysis of 3D structures using AutoDock vina-1.5.7 server predicted four ligand binding active site residues at Gln70, Asp68, Leu68, and Leu63. Strong ArsC–arsenate ion interaction was observed with binding energy −1.03 kcal/mol, indicating significant arsenate reductase activity and specificity of ArsC protein. On the basis of molecular dynamics simulation analysis, the RMSD and RMSF values revealed the stability of ArsC protein from E. cloacae RSC3.

COVID-19 is a global health crisis which has not been experienced by anyone in the modern days. Every person has been affected by the pandemic in one way or the other. This study explores the strategies taken up by the organizations and the Individuals to cope up with the challenges posed by the Pandemic. It also explores the Covid-19 stressors responsible for the psychological distress among the employees. It has been found that there is a considerable impact on the behavior of employees due to COVID-19. Stressors like fear of unknown, improper communication, future uncertainty, lack of clarity and role ambiguity, no clarity about the plans to resume work, social isolation are responsible for creating psychological distress among the employees.