Bacillus velezensis RC 218 as a biocontrol agent to reduce Fusarium head blight and deoxynivalenol accumulation: Genome sequencing and secondary metabolite cluster profiles

PALAZZINI J.; DUNLAP C; BOWMAN M; CHULZE SN.

MICROBIOLOGICAL RESEARCH

ELSEVIER GMBH

Año: 2016 p. 30 - 36

0944-5013

Bacillus subtilis RC 218 was originally isolated from wheat anthers as a potential antagonist of Fusariumgraminearum, the causal agent of Fusarium head blight (FHB). It was demonstrated to have antagonistactivity against the plant pathogen under in vitro and greenhouse assays. The current study extends char-acterizing B. subtilis RC 218 with a field study and genome sequencing. The field study demonstrated thatB. subtilis RC 218 could reduce disease severity and the associated mycotoxin (deoxynivalenol) accumu-lation, under field conditions. The genome sequencing allowed us to accurately determine the taxonomyof the strain using a phylogenomic approach, which places it in the Bacillus velezensis clade. In addition,the draft genome allowed us to use bioinformatics to mine the genome for potential metabolites. Thegenome mining allowed us to identify 9 active secondary metabolites conserved by all B. velezensis strainsand one additional secondary metabolite, the lantibiotic ericin, which is unique to this strain. This studyrepresents the first confirmed production of ericin by a B. velezensis strain. The genome also allowed usto do a comparative genomics with its closest relatives and compare the secondary metabolite produc-tion of the publically available B. velezensis genomes. The results showed that the diversity in secondarymetabolites of strains in the B. velezensis clade is driven by strains making different antibacterials.