Isolation, Identification, and Complete Genome Assembly of an Endophytic Bacillus velezensis YB-130, Potential Biocontrol Agent Against Fusarium graminearum
Wen Xu, Liyong Zhang, Paul H. Goodwin, Mingcong Xia, Jie Zhang, Qi Wang, Juan Boo Liang, Runhong Sun, Chao Wu, Lirong Yang
Abstract
Wheat scab caused by F. graminearum is a highly destructive disease that leads to yield reduction and mycotoxin contamination of grains. In this study, an endophytic bacterium of strain YB-130 was isolated from surface sterilized wheat spikes with scab symptoms and identified as Bacillus velezensis by whole genome annotation, 16S rRNA gene and average nucleotide identities analysis. The whole-genome sequence of strain YB-130 was obtained by PacBio sequencing. 88 putative Carbohydrate-Active Enzymes and 12 gene clusters encoding for secondary metabolites were identified in the YB-130 genome, including one gene cluster for the synthesis of lanthipeptide only found in strain YB-130 genome. In dual cultures, strain YB-130 significantly inhibited the growth of F. graminearum PH-1 and other eight fungal plant pathogens, indicating a broad antifungal activity. Furthermore, strain YB-130 was able to significantly inhibit spore morphology and hyphal development of F. graminearum PH-1. Strain YB-130 also reduced deoxynivalenol production by F. graminearum PH-1 in dual cultures, possibly due to its ability to suppress the expression of tri5 , tri3 , and tri8 that are required for deoxynivalenol production in F. graminearum . Overall, B. velezensis YB-130 is a promising biological control agent of both F. graminearum infection and mycotoxin production.