Exploring the Genome-wide Expression Level of the Bacterial Strain Belonging to Bacillus safensis (MM19) Against Phomopsis viticola.

Rhizobacteria have the ability to compete with pathogenic microorganisms and contribute to plant immunity and defense mechanisms. Their growth and survival in the rhizosphere ensure a biological balance in favor of the host plant. The differential gene expression profiles of B. safensis (MM19) revealed significantly increased expression of prominent genes related to thiamine biosynthesis involving various metabolites and enzymes that participate in the suppression of mycelium growth and pathogen inhibition. Correspondingly, the expression of three major genes (HOG1, FUS3, SGI) involved in the virulence of P. viticola was assessed using qPCR analysis. HOG1 was the highest expressed gene in the pathogen when it was co-cultivated with MM19. Based on these findings, we performed molecular docking and dynamics analysis to explore the interaction between HOG1 and thiamine, as well as expression network analysis constructed using Cytoscape. The functional genomic data related to thiamine biosynthesis and the corresponding pathways ensure a priming role in the antagonistic behavior of B. safensis (MM19) against P. viticola as a support for plant immunity.