Work

The extracytoplasmic sigma factor σX supports biofilm formation and increases biocontrol efficacy in Bacillus velezensis 118

Year: 2025

Type: article

Abstract: Plant growth promoting rhizobacteria (PGPR) offer an environmentally friendly and sustainable approach to combat pathogens and enhance crop production. The biocontrol activity of PGPR depends on their ability to colonize plant roots and synthesize antimicrobial compounds that inhibit pathogens. However, the regulatory mechanisms underlying these processes remain unclear. In this study, we isolated and characterized Bacillus velezensis 118, a soil isolate that exhibits potent biocontrol activity against Fusarium wilt of banana. Deletion of sigX, encoding an extracytoplasmic function (ECF) sigma factor previously implicated in controlling biofilm architecture in B. subtilis, reduced biocontrol efficacy. The B. velezensis 118 sigX mutant displayed reduced biofilm formation but had only a minor defect in swarming motility and a negligible impact on lipopeptide production. These findings highlight the importance of regulatory processes important for root colonization in the effectiveness of Bacillus spp. as biocontrol agents against phytopathogens.

Source: Scientific Reports

DOI: 10.1038/s41598-025-89284-7

Authors: Yanfei Cai, Huan Tao, Ahmed Gaballa, Hualiang Pi, John D. Helmann

Institutions: South China Agricultural University, Cornell University, Yale University

Language: English

Topic: Plant-Microbe Interactions and Immunity

Subfield: Plant Science

Field: Agricultural and Biological Sciences

Domain: Life Sciences

SDG: Zero hunger

Open Access status: gold

Estimated APC paid: $2,690