Isolation and identification of Bacillus velezensis RJW-5-5 and gene cluster mining of bacteriocin and RiPPs

Abstract:

[Background] Chemical control pollution is becoming more and more serious, “3R” problems are becoming more and more common. Therefore, screening new biocontrol strains and studying their antibacterial substances have become a hot spot. [Objective] To screen a strain of Bacillus velezensis that has biocontrol function against phytopathogenic bacteria such as Cochlioboluss ativus, and excavate its gene clusters that regulate the synthesis of bacteriocins and RiPPs (antibacterial peptides synthesized by ribosome pathway). [Methods] Strains were screened by methods such as separation and screening, confrontation culture, etc., and strain identification was performed by whole cell fatty acid, Biolog analysis and molecular biology methods. The Illumina Novaseq 6000 platform was used to determine the whole genome sequence, and the potential bacteriocins, RiPPs gene clusters and potential mechanisms of action were explored through BAGEL4. [Results] strain RJW-5-5 had the best inhibitory effect on Cochlioboluss ativus, and the inhibition rate reached 78.4%. Strain RJW-5-5 was identified as Bacillus velezensis. [Conclusion] strain RJW-5-5 can inhibit various crop diseases, has a variety of lantibiotic, lasso peptide, bacteriocin and other antibacterial peptide gene clusters, with broad development prospects and application potential.