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Biology subjects

Mohd, A.

Publications and source records attributed to Mohd, A..

2 recordsLinked to original sources

Agroforestry reshapes soil bacterial communities to enhance Ricinus communis oil quality and bioactivity over monocropping: comparative metagenomics and culture-dependent insights

An agroforestry (AF) system improves crop quality, ecosystem services, and microbial resilience, but its effects on oilseed bioactivity and soil microbiomes are still underexplored. This study compared AF and monocropping systems for castor (Ricinus communis L.) grown in Rajasthan, India, to evaluate plant productivity, seed oil composition, antimicrobial properties, and soil bacterial communities. AF enhanced seed morphology and germination. Castor oil from agroforestry had a 2.4-fold higher phenolic content, 2% more ricinoleic acid, and lower levels of oleic and linoleic acids compared to monocropping, confirmed by infrared spectroscopy and gas chromatography, along with increased expression of the RcDGAT2 gene involved in fatty acid biosynthesis. This led to improved antimicrobial activity against Bacillus mobilis and Pseudomonas fluorescens. Full-length 16S rRNA gene sequencing on the Nanopore platform identified 17 bacterial phyla in soil microbiomes, with Proteobacteria and Firmicutes as the dominant phyla. While alpha diversity was similar, AF soils showed distinct taxonomic shifts, enriching bacteria such as Alkalimonas, Aureimonas, Blastopirellula, Glutamicibacter, Rhizobium, Rhizomicrobium, and Rhodovulum, linked to nutrient cycling and plant growth promotion. Isolated rhizospheric/root endophytic Bacillus safensis and Enterobacter cloacae from AF castor exhibited plant growth-promoting traits via biochemical tests and whole-genome sequencing; their oil biosynthesis genes likely contribute to host oil quality by enhancing precursor supply and phenolic pathways. These isolates enhanced the growth of the model plant Arabidopsis thaliana. In summary, AF enhances the bioactivity of castor oil and microbial functions by modulating plant-soil-microbe interactions, thereby supporting sustainable crop quality and soil health.

microbiology↗

Oral administration of engineered recombinant outer membrane vesicles-based nano-vaccine formulation triggers robust mucosal and systemic humoral immunity against poultry pathogens

Although vaccination is an integral part of poultry health management, affordable, scalable, and easily administrable new-generation vaccine discovery platforms are required to combat emerging infectious diseases. Oral vaccines offer an alternative to injectable options owing to their ease of administration; however, existing platforms fail to confer robust protective systemic and mucosal immunity. Here, we used engineered outer membrane vesicles (rOMVs) displaying the desired vaccine antigens, and derived from hypervesiculating probiotic E coli Nissle 1917 (EcN) [36], which elicits both mucosal and systemic immunity when administered orally. Using such approach, we attempted to formulate rOMV based single Oral vaccine against Newcastle Disease Virus (NDV) and Infectious Bursal Disease Virus (IBDV), which pose significant risks to the poultry sector. We engineered rOMVs to display the antigenic regions of immunodominant Hemagglutinin-Neuraminidase (HN) and Viral Protein 2 (VP2) of NDV and IBDV, respectively, on their surface, with sizes less than 150 nm and considerable polydispersity. The Oral administration of these rOMVs expressing the HN and VP2 induced a robust immune response which shows enhanced production of high-titer antigen-specific sIgA and IgG, which were able to neutralize the virus effectively in an in-vitro infection model system. While the poultry pathogens such as NDV and IBDV served as a model, the rOMV-based platforms hold considerable potential for the development of a multivalent oral biotherapeutic agent, including vaccines against a wide range of emerging human and animal pathogens by engineering rOMVs to display immunodominant antigenic portions, demonstrating its capability as a next-generation oral vaccine discovery platform.

immunology↗