Genomic insights and biosynthetic gene cluster analysis of Streptomyces chrestomyceticus strain B5 showing antimicrobial activities Aruna Kumari, Sonam Nain, Praveen Singh, Nar Singh Chauhan, Swarnendu Bag, Rakesh Sharma Microbiology Spectrum, 2026 Streptomyces bacteria are known for their different biological activities and enormous biosynthetic potential. Fungal pathogens, especially Candida auris, have emerged as clinically important pathogens involved in causing systemic infections and high mortality. Therefore, antimicrobial compounds effective against C. auris are needed to tackle infections caused by these multidrug-resistant yeast pathogens. A soil bacterium was isolated from soil in Delhi, India, exhibited broad-spectrum antimicrobial activities against various pathogenic bacteria, such as Bacillus subtilis , Staphylococcus aureus, and Escherichia coli, and pathogenic fungi, including Candida albicans, Fusarium oxysporum, Aspergillus fumigatus, and Candida glabrata . It was subjected to whole-genome sequencing and resulted in a high-quality draft genome with a single contig of 9.61 Mb genome size and 72.1% GC content. Phylogenetic analysis and average nucleotide identity identified that the strain belongs to Streptomyces chrestomyceticus . The genome annotation predicted plant growth-promoting traits and stress-response genes. Genome mining revealed non-ribosomal peptide synthetase, polyketide synthase (PKS), and hybrid biosynthetic gene clusters (BGCs) synthesizing known and unknown metabolites. Most of the encoded compounds by the BGCs were reported for antibacterial and antitumor activities, and two BGCs were identified as antifungal clusters. A trans-acyltransferase polyketide synthase (transAT-PKS) cluster was identified with 27% and 19% similarity to cycloheximide and 9-methylstreptimidone clusters, respectively. The comparison of 9-methylstreptimidone and transAT-PKS cluster revealed differences in the organization of genes in closely related strains. The crude extract of S. chrestomyceticus B5 possessed strong antibacterial and antifungal activities. The bioassay-guided purification and LC-MS identified an antifungal compound (streptimidone derivative or isomer, molecular mass 293.1 Da), which specifically inhibited C. glabrata and C. auris . The transAT-PKS cluster might be responsible for encoding this streptimidone derivative or isomer. IMPORTANCE The study highlighted the biosynthetic potential of Streptomyces chrestomyceticus B5, which is a promising strain for producing various bioactive metabolites and is rich in biosynthetic gene clusters responsible for encoding multiple metabolites and producing an antifungal compound, a streptimidone derivative or isomer, active against drug-resistant Candida auris .
Stenotrophomonas maltophilia promotes wheat growth by enhancing nutrient assimilation and rhizosphere microbiota modulation Pinki Sharma, Rajesh Pandey, Nar Singh Chauhan Frontiers in Bioengineering and Biotechnology, 2025 Background Stenotrophomonas maltophilia has gained considerable attention for its biocontrol and biofertilizer potential in promoting plant growth. It could be employed to enhance wheat yield to ensure food security for the growing population. However, its biofertilizer potential in field conditions and its impact on wheat rhizosphere microbiota must be assessed before its employment in agriculture practices to increase wheat production. Methods We have assessed the role of S. maltophilia on wheat seed germination, plant growth parameters, and crop yield in the field conditions. Additionally, wheat rhizosphere microbiota was explored to assess the impact of seed pretreatment with S. maltophilia on the wheat rhizosphere microbiota. Results and discussion S. maltophilia strains BCM and BCM_F demonstrated superior antifungal activity, indicating their biocontrol potential. Seed pretreatment with these strains promoted nitrogen fixation and phosphate solubilization in the wheat rhizosphere showcasing biofertilizer potential. Uniquely identified OTUs in the rhizosphere microbiota of treated groups and microbial community dynamics, particularly at Feeks 3.0 and 6, indicated S. maltophilia -induced microbiota restructuring. The abundance of S. maltophilia 16S rRNA gene sequences at different Feeks treated with microbial indicates its stability across different plant growth stages. Their rhizospheric presence also impacted plant health indicators, including improved sugar and nitrite concentrations and significantly enhanced crop yield ( P < 0.05). Enhanced growth parameters and better crop yield in S. maltophilia pre-inoculated seeds in field conditions indicated their potential to offer a sustainable alternative to enhance wheat production. Conclusion The present study highlighted the biofertilizer and biocontrol potential of S . maltophilia strains BCM and BCM_F in supporting sustainable agricultural practices.
Assessment of the wheat growth-promoting potential of Delftia lacustris strain NSC through genomic and physiological characterization Pinki Sharma, Rajesh Pandey, Nar Singh Chauhan Frontiers in Microbiology, 2025 BackgroundDelftia species have attracted significant interest for their biofertilizer and biocontrol capabilities, particularly in promoting the growth of crops such as Oryza sativa, Brassica campestris, and Solanum lycopersicum. However, their potential in supporting wheat cultivation remains largely unexplored.MethodsA culture-dependent approach was employed to isolate a Delftia strain from the wheat rhizosphere. The biofertilizer potential of the isolate was systematically evaluated through a series of physiological, biochemical, and molecular assays, as well as field trials to assess its efficacy under agronomic conditions.Results and discussionCulture-dependent investigation of the wheat rhizosphere led to the isolation of a multifunctional plant growth-promoting bacterium, designated as strain NSC. Morphological and physiological characterization identified NSC as a gram-negative, rod-shaped, motile bacterium with optimal growth at pH 7.0 and 35°C. Phylogenetic and phylogenomic analyses confirmed its taxonomic identity as Delftia lacustris. In vitro assays revealed its ability to solubilize phosphate (0.325 IU), reduce nitrate (0.401 IU), produce indole-3-acetic acid (0.485 IU), and exhibit ACC deaminase activity (0.512 IU) and siderophore production. The strain demonstrated strong antifungal activity against Fusarium oxysporum and Rhizoctonia solani. Strain NSC exhibited significant tolerance to abiotic stresses, including drought [up to 40% PEG (w/v)], heavy metals, and high salinity [up to 11.69% NaCl (w/v), 11.18% KCl (w/v), and 4.24% LiCl (w/v)]. Genome analysis identified key genes associated with phosphate solubilization (PhoR, PhoB, PhoU, PstABCD), nitrogen fixation (nifC, nifU), auxin and siderophore biosynthesis, rhizosphere colonization, and antifungal mechanisms (chitinase, PhnZ). In planta studies showed significantly enhanced seed germination (93.33% ± 0.23), seedling growth, and biomass accumulation under stress conditions (p < 0.05). Field trials further validated the strain’s efficacy, showing marked improvements in plant growth and yield parameters (p = 0.0001). These results underscore the potential of D. lacustris NSC as an effective biofertilizer and biocontrol agent for sustainable agriculture.ConclusionDelftia lacustris strain NSC exhibits multifunctional plant growth-promoting and biocontrol activities, including enhanced nutrient mobilization, pathogen suppression, and abiotic stress tolerance. Its demonstrated efficacy under field conditions and environmentally benign profile highlight its potential as a sustainable bioinoculant for wheat production systems.
Peribacillus frigoritolerans T7-IITJ, a potential biofertilizer, induces plant growth-promoting genes of Arabidopsis thaliana Debankona Marik, Pinki Sharma, Nar Singh Chauhan, Neelam Jangir, Rajveer Singh Shekhawat, Devanshu Verma, Manasi Mukherjee, Moses Abiala, Chandan Roy, Pankaj Yadav, Ayan Sadhukhan Journal of Applied Microbiology, 2024 Aims This study aimed to isolate plant growth and drought tolerance-promoting bacteria from the nutrient-poor rhizosphere soil of Thar desert plants and unravel their molecular mechanisms of plant growth promotion. Methods and results Among our rhizobacterial isolates, Enterobacter cloacae C1P-IITJ, Kalamiella piersonii J4-IITJ, and Peribacillus frigoritolerans T7-IITJ, significantly enhanced root and shoot growth (4˗5-fold) in Arabidopsis thaliana under PEG-induced drought stress. Whole genome sequencing and biochemical analyses of the non-pathogenic bacterium T7-IITJ revealed its plant growth-promoting traits, viz., solubilization of phosphate (40−73 µg/ml), iron (24 ± 0.58 mm halo on chrome azurol S media), and nitrate (1.58 ± 0.01 µg/ml nitrite), along with production of exopolysaccharides (125 ± 20 µg/ml) and auxin-like compounds (42.6 ± 0.05 µg/ml). Transcriptome analysis of A. thaliana inoculated with T7-IITJ and exposure to drought revealed the induction of 445 plant genes (log2fold-change > 1, FDR < 0.05) for photosynthesis, auxin and jasmonate signalling, nutrient uptake, redox homeostasis, and secondary metabolite biosynthesis pathways related to beneficial bacteria-plant interaction, but repression of 503 genes (log2fold-change < −1) including many stress-responsive genes. T7-IITJ enhanced proline 2.5-fold, chlorophyll 2.5˗2.8-fold, iron 2-fold, phosphate 1.6-fold, and nitrogen 4-fold, and reduced reactive oxygen species 2˗4.7-fold in plant tissues under drought. T7-IITJ also improved the germination and seedling growth of Tephrosia purpurea, Triticum aestivum, and Setaria italica under drought and inhibited the growth of two plant pathogenic fungi, Fusarium oxysporum, and Rhizoctonia solani. Conclusions P. frigoritolerans T7-IITJ is a potent biofertilizer that regulates plant genes to promote growth and drought tolerance.
Design, synthesis and exploration of novel triazinoindoles as potent quorum-sensing inhibitors and radical quenchers Jyoti Rasgania, Renu Gavadia, Neetu Sahu, Pinki Sharma, Nar S Chauhan, Vicky Saharan, Rajeev K Kapoor, Komal Jakhar Future Medicinal Chemistry, 2024 Background: Antimicrobial resistance has become a critical health concern, and quorum-sensing exacerbates the resistance by facilitating cell-to-cell communication within the microbial community, leading to severe pathogenic outbreaks. Methods & results: Novel 1-(2-((5H-[1,2,4]-triazino[5,6-b]indol-3-yl)thio)acetyl)indoline-2,3-diones were synthesized. The title compounds exhibit outstanding anti-quorum-sensing efficacy, and compound 7g demonstrated the maximum proficiency (IC50 = 0.0504 μg/ml). The hybrids displayed potent antioxidant action, and compound 7c showed the highest antioxidant ability (IC50 = 40.71 μg/ml). Molecular docking of the isatin hybrids against DNA gyrase and quorum-sensing receptor CviR validated the observed in vitro findings. The befitting pharmacokinetic profile of the synthesized drug candidates was ascertained through absorption, distribution, metabolism, excretion and toxicity screening. Conclusion: The remarkable biocompetence of the synthesized triazinoindoles may help to combat drug-resistant infections.
Bacteria Pinki Sharma, Pooja Yadav, Nar Singh Chauhan Pathogens and Environmental Impact on Life Forms Understanding Pathogens and Host Defence Mechanisms, 2024
Sources of endogenous biostimulants Pinki Sharma, Nar Singh Chauhan Biostimulants in Alleviation of Metal Toxicity in Plants Emerging Trends and Opportunities, 2023
Targeting the redox regulatory mechanisms for abiotic stress tolerance in crops Punam Kundu, Ritu Gill, Shruti Ahlawat, Naser A. Anjum, Krishna K. Sharma, Abid A. Ansari, Mirza Hasanuzzaman, Akula Ramakrishna, Narsingh Chauhan, Narendra Tuteja, Sarvajeet S. Gill Biochemical Physiological and Molecular Avenues for Combating Abiotic Stress in Plants, 2018
CuS and Ag integrated Sb2O3 nanosheets: Formation, charge transfer enhancement and investigation for photocatalytic decontamination of organic pollutants S Jain, M Kumari, N Kumar, NS Chauhan, A Sharma, PR Makgwane, ... Catalysis Today, 115856 , 2026 2026
Genomic insights and biosynthetic gene cluster analysis of Streptomyces chrestomyceticus strain B5 showing antimicrobial activities A Kumari, S Nain, P Singh, NS Chauhan, S Bag, R Sharma Microbiology Spectrum, e02688-25 , 2026 2026
A desert endophyte, Priestia megaterium SI1-IITJ, improves fluoride stress tolerance by reducing fluoride content of plant tissues and perturbing salt tolerance and defense … D Verma, P Sharma, R Kumar, N Jangir, V Prajapat, D Marik, R Mandi, ... Journal of Plant Growth Regulation 45 (3), 2106-2139 , 2026 2026 Citations: 2
Agroforestry reshapes soil bacterial communities to enhance Ricinus communis oil quality and bioactivity over monocropping: comparative metagenomics and culture-dependent insights K Saharan, P Pagaria, T Bano, N Chauhan, R Mandi, A Mohd, R Jameriya, ... bioRxiv, 2026.04. 24.720747 , 2026 2026
Host-microbiota immuno-interactions for personalized microbial therapeutics S Gupta, SK Raghav, NS Chauhan Frontiers in Immunology 16, 1716098 , 2025 2025
Assessment of the wheat growth-promoting potential of Delftia lacustris strain NSC through genomic and physiological characterization P Sharma, R Pandey, NS Chauhan Frontiers in Microbiology 16, 1576536 , 2025 2025 Citations: 4
Stenotrophomonas maltophilia promotes wheat growth by enhancing nutrient assimilation and rhizosphere microbiota modulation P Sharma, R Pandey, NS Chauhan Frontiers in Bioengineering and Biotechnology 13, 1563670 , 2025 2025 Citations: 7
Assessing wheat growth promotion potential of Delftia lacustris strain NSC through genomic and physiological characterization P Sharma, R Pandey, NS Chauhan 2025
Exploring the influence of age and diet on gut microbiota development in children during the first 5 years: a study from Yaoundé, Cameroon JJB Adjele, P Devi, P Kumari, A Yadav, AD Tchuenchieu Kamgain, ... Frontiers in microbiology 15, 1512111 , 2024 2024 Citations: 7
Bacteria P Sharma, P Yadav, NS Chauhan Pathogens and Environmental Impact on Life Forms: Understanding Pathogens … , 2024 2024
Unveiling wheat growth promotion potential of phosphate solubilizing Pantoea agglomerans PS1 and PS2 through genomic, physiological, and metagenomic … P Sharma, R Pandey, NS Chauhan Frontiers in Microbiology 15, 1467082 , 2024 2024 Citations: 15
Peribacillus frigoritolerans T7-IITJ, a potential biofertilizer, induces plant growth-promoting genes of Arabidopsis thaliana D Marik, P Sharma, NS Chauhan, N Jangir, RS Shekhawat, D Verma, ... Journal of Applied Microbiology 135 (4), lxae066 , 2024 2024 Citations: 23
Biofertilizer and biocontrol properties of Stenotrophomonas maltophilia BCM emphasize its potential application for sustainable agriculture P Sharma, R Pandey, NS Chauhan Frontiers in Plant Science 15, 1364807 , 2024 2024 Citations: 32
Design, synthesis and exploration of novel triazinoindoles as potent quorum-sensing inhibitors and radical quenchers J Rasgania, R Gavadia, N Sahu, P Sharma, NS Chauhan, V Saharan, ... Future Medicinal Chemistry 16 (5), 399-416 , 2024 2024 Citations: 6
Current perspectives on fecal microbiota transplantation in inflammatory bowel disease A Singh, V Midha, NS Chauhan, A Sood Indian Journal of Gastroenterology 43 (1), 129-144 , 2024 2024 Citations: 13
Unraveling the genetic evolution of SARS-CoV-2 Recombinants using mutational dynamics across the different lineages V Ravi, U Shamim, MA Khan, A Swaminathan, P Mishra, R Singh, ... Frontiers in Medicine 10, 1294699 , 2024 2024 Citations: 9
THEMATIC EVOLUTION OF WORKPLACE INCLUSION: A BIBLIOMETRIC ANALYSIS OF EMPLOYEE AND MANAGEMENT PERSPECTIVES N CHAUHAN, PK AHLAWAT SHODHKOSH: JOURNAL OF VISUAL AND PERFORMING ARTS Учредители: Granthaalayah … , 2024 2024
Modulatory role of plant-derived metabolites on host-microbiota interactions: personalized therapeutics outlook P Yadav, N Chauhan Biocell 48 (8), 1127 , 2024 2024 Citations: 2
Molecular mechanisms of nanomaterial interaction with plants P Sharma, N Chauhan Nanotechnology for Abiotic Stress Tolerance and Management in Crop Plants, 77-93 , 2024 2024
Role of gut-microbiota in disease severity and clinical outcomes M Yadav, NS Chauhan Briefings in Functional Genomics 23 (1), 24-37 , 2024 2024 Citations: 10
MOST CITED SCHOLAR PUBLICATIONS
A review of metabolic potential of human gut microbiome in human nutrition M Yadav, MK Verma, NS Chauhan Archives of microbiology 200 (2), 203-217 , 2018 2018 Citations: 317
Microbiome therapeutics: exploring the present scenario and challenges M Yadav, NS Chauhan Gastroenterology report 10, goab046 , 2022 2022 Citations: 142
Metagenomic profiling of soil microbes to mine salt stress tolerance genes V Ahmed, MK Verma, S Gupta, V Mandhan, NS Chauhan Frontiers in Microbiology 9, 159 , 2018 2018 Citations: 128
Identification of genes conferring arsenic resistance to Escherichia coli from an effluent treatment plant sludge metagenomic library NS Chauhan, R Ranjan, HJ Purohit, VC Kalia, R Sharma FEMS Microbiology Ecology 67 (1), 130-139 , 2009 2009 Citations: 112
TiO 2 and its composites as promising biomaterials: a review N Kumar, NS Chauhan, A Mittal, S Sharma Biometals 31 (2), 147-159 , 2018 2018 Citations: 109
Physiopathology and management of gluten‐induced celiac disease J Kumar, M Kumar, R Pandey, NS Chauhan Journal of food science 82 (2), 270-277 , 2017 2017 Citations: 93
Amperometric choline biosensor based on multiwalled carbon nanotubes/zirconium oxide nanoparticles electrodeposited on glassy carbon electrode S Pundir, N Chauhan, J Narang, CS Pundir Analytical biochemistry 427 (1), 26-32 , 2012 2012 Citations: 90
Highly efficient, visible active TiO 2 /CdS/ZnS photocatalyst, study of activity in an ultra low energy consumption LED based photo reactor A Mittal, S Sharma, V Kumari, S Yadav, NS Chauhan, N Kumar Journal of Materials Science: Materials in Electronics 30 (19), 17933-17946 , 2019 2019 Citations: 88
An improved methodology to overcome key issues in human fecal metagenomic DNA extraction J Kumar, M Kumar, S Gupta, V Ahmed, M Bhambi, R Pandey, ... Genomics, proteomics & bioinformatics 14 (6), 371-378 , 2016 2016 Citations: 78
Hypoxia inducible factor-1α: the curator of gut homeostasis T Kumar, R Pandey, NS Chauhan Frontiers in Cellular and Infection Microbiology 10, 227 , 2020 2020 Citations: 76
Chemical activation of egg shell membrane for covalent immobilization of enzymes and its evaluation as inert support in urinary oxalate determination CS Pundir, M Bhambi, NS Chauhan Talanta 77 (5), 1688-1693 , 2009 2009 Citations: 72
Western Indian Rural Gut Microbial Diversity in Extreme Prakriti Endo-Phenotypes Reveals Signature Microbes NS Chauhan, R Pandey, AK Mondal, S Gupta, MK Verma, S Jain, ... Frontiers in microbiology 9, 118 , 2018 2018 Citations: 69
Identification of two flavin monooxygenases from an effluent treatment plant sludge metagenomic library A Singh, NS Chauhan, HV Thulasiram, V Taneja, R Sharma Bioresource technology 101 (21), 8481-8484 , 2010 2010 Citations: 67
Comparative analysis of the alveolar microbiome in COPD, ECOPD, Sarcoidosis, and ILD patients to identify respiratory illnesses specific microbial signatures S Gupta, M Shariff, G Chaturvedi, A Sharma, N Goel, M Yadav, ... Scientific Reports 11 (1), 3963 , 2021 2021 Citations: 65
TiO2/SnO2 nano-composite: New insights in synthetic, structural, optical and photocatalytic aspects S Sharma, N Kumar, PR Makgwane, NS Chauhan, K Kumari, M Rani, ... Inorganica Chimica Acta 529, 120640 , 2022 2022 Citations: 63
Solution combustion synthesized TiO2/Bi2O3/CuO nano-composites and their photocatalytic activity using visible LEDs assisted photoreactor S Sharma, N Kumar, B Mari, NS Chauhan, A Mittal, S Maken, K Kumari Inorganic Chemistry Communications 125, 108418 , 2021 2021 Citations: 63
Targeting the redox regulatory mechanisms for abiotic stress tolerance in crops P Kundu, R Gill, S Ahlawat, NA Anjum, KK Sharma, AA Ansari, ... Biochemical, physiological and molecular avenues for combating abiotic … , 2018 2018 Citations: 63
Construction of triglyceride biosensor based on nickel oxide–chitosan/zinc oxide/zinc hexacyanoferrate film J Narang, N Chauhan, CS Pundir International journal of biological macromolecules 60, 45-51 , 2013 2013 Citations: 61
Mapping of the benzoate metabolism by human gut microbiome indicates food-derived metagenome evolution M Yadav, A Lomash, S Kapoor, R Pandey, NS Chauhan Scientific reports 11 (1), 5561 , 2021 2021 Citations: 59
Immobilization of lysine oxidase on a gold–platinum nanoparticles modified Au electrode for detection of lysine N Chauhan, J Narang, CS Pundir Enzyme and microbial technology 52 (4-5), 265-271 , 2013 2013 Citations: 55