Organization, evolution and function of fengycin biosynthesis gene clusters in the Bacillus amyloliquefaciens group

Phytopathology Research

Jianbo Xie¹  Qi Wang²  Xiaofei Gu²  Panlei Yang²  Xinyi Chen²  Yan Li²  Qingchao Zeng³  Guangcan Hu⁴ 

[1] Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, 100083, Beijing, China;Department of Plant Pathology, MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, 100193, Beijing, China;Department of Plant Pathology, MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, 100193, Beijing, China;Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, 100083, Beijing, China;Institute of Citrus Science, 443000, Yichang, China;

关键词: Bacillus amyloliquefaciens;    Biocontrol;    Comparative genomic;    Evolution;    Genome sequencing;   

DOI  :  10.1186/s42483-021-00103-z

来源: Springer

【 摘 要 】

The Bacillus velezensis strain PG12, belonging to the Bacillus amyloliquefaciens group, is an endophytic bacterium known for its antimicrobial activities against crop pathogens. However, our knowledge of the molecular basis underlying its biocontrol activity and the relatedness of different strains in the Bacillus amyloliquefaciens group is limited. Here, we sequenced and analyzed the genome of PG12 to test its taxonomic affiliation and identified genes involved in the biocontrol activity. The phylogenomic analysis results indicate that PG12 belongs to B. velezensis, a subgroup of the B. amyloliquefaciens group. By comparing the genomes of 22 strains in this group, we confirmed that it comprises three different phylogenetic lineages: B. amyloliquefaciens, B. velezensis and B. siamensis. Three secondary metabolism gene clusters related to the production of lipopeptides, namely fengycin, iturin and surfactin, were identified in the genomes of the B. amyloliquefaciens group. The core genome of B. velezensis is enriched in secondary metabolism genes compared with B. siamensis and B. amyloliquefaciens. Three of the five genes pertaining to the gene cluster responsible for fengycin biosynthesis (fenBCD) were found in B. velezensis and B. siamensis, but not in B. amyloliquefaciens. Phenotypic analysis showed that the ∆fenA mutant of PG12 displayed significantly decreased biofilm formation and swarming motility, which indicates that fengycin contributes to the colonization and pathogen control abilities of PG12. Our results also suggest that B. siamensis and B. velezensis have acquired the fenBCD genes from Paenibacillus spp. by horizontal gene transfer (HGT). Taken together, the results provide insights into the evolutionary pattern of the B. amyloliquefaciens group strains and will promote further researches on their taxonomy and functional genomics.

【 授权许可】

CC BY