Improvement and tolerance mechanisms of Priestia megaterium to salt ions
Year: 2025
Type: article
Abstract: Introduction Salinity is a major abiotic stress threatening global agriculture. While some microorganisms are known to ameliorate soil salinity and promote plant growth, the underlying mechanisms, particularly for Priestia megaterium (formerly Bacillus megaterium ), remain less explored. Methods Here, we investigated the efficacy and mechanism of P. megaterium NCT-2 in improving secondary saline soil by elemental analysis, 15N tracing, gene knockout and transcriptomics. Results Our results demonstrated that the NCT-2 agent significantly reduced the content of key salt ions, notably NO₃ − , Cl − , and Na + in soil. Through a combination of biochemical assays, isotope tracing, and gene knockout techniques, we identified that the aerobic assimilation pathway is the primary route for nitrate metabolism in NCT-2, with the nasC and nasD genes being crucial for this process. Furthermore, transcriptomic analysis under salt stress revealed that NCT-2 employs a multi-faceted tolerance strategy, which includes enhancing sporulation, activating antioxidant defenses (e.g., CAT, SOD), assembling flagella, and forming vesicles. Concurrently, the strain upregulates central carbon metabolism (TCA cycle, glycolysis) and amino acid synthesis to fuel these adaptive responses. Discussion This study provides a comprehensive theoretical foundation for using P. megaterium NCT-2 in environmental remediation and identifies key genetic targets for enhancing microbial salt tolerance.
Source: Frontiers in Microbiology
Authors: Chunlong Wang, Shaohua Chu, Dan Zhang, Pei Zhou, Yimin You
Language: English
Subfield: Plant Science
Domain: Life Sciences
SDG: Zero hunger
Open Access status: gold
Estimated APC paid: $3,801
OpenAlex ID: W4417449569