# Multifunctional Bioactivity of Bacillus amyloliquefaciens SH-53: Analysis of Multiple Antagonistic and Synergistic Growth Promotion Mechanisms Based on Whole Genome

## TL;DR

This study explores the genome of Bacillus amyloliquefaciens SH-53, revealing its potential as a biocontrol agent due to its diverse bioactive properties and unique genetic features.

## Contribution

The study identifies novel biosynthetic gene clusters and functional mechanisms in SH-53 that are distinct from conventional biocontrol strains.

## Key findings

- SH-53 has 12 biosynthetic gene clusters, 7 of which are novel and functionally distinct.
- The strain exhibits antagonistic activity against plant pathogens and promotes plant growth through multiple mechanisms.
- Genomic analysis shows SH-53 has a complete gene network for induced systemic resistance and secondary metabolism.

## Abstract

Bacillus amyloliquefaciens is an important agricultural microbial resource. This study focuses on the whole genome analysis and functional characterization of B. amyloliquefaciens SH-53, isolated from the Wuliang Mountain National Nature Reserve in Dali, Yunnan. The genomic feature analysis revealed that the genome of SH-53 contains 27 ribosomal RNA operons, 4078 protein-coding genes, and 250 prophage-related genes. Additionally, 12 biosynthetic gene clusters (BGCs) for secondary metabolites were predicted, of which 7 are novel gene clusters with unknown functions, showing significant differences compared to the known BGCs of conventional biocontrol strains. Functional potential analysis indicates that SH-53 possesses potential antagonistic activity against plant pathogenic bacteria and can colonize the plant rhizosphere through various mechanisms to exert growth-promoting effects. It is capable of synthesizing multiple antibacterial secondary metabolites, indole-3-acetic acid (IAA), iron carriers, secreting amylase, and efficiently utilizing sulfur sources. The genome also harbors a complete core gene network related to the induced systemic resistance (ISR) and supporting genes that maintain secondary metabolism homeostasis. In conclusion, B. amyloliquefaciens SH-53 exhibits rich biocontrol-related characteristics and unique secondary metabolic potential, indicating promising prospects for its development as an excellent biocontrol agent.