Whole-Genome Analysis of Bacillus paranthracis Qf-1 Isolated from Mink (Neogale vison)

Bacillus paranthracis, a species of the genus Bacillus, is a Gram-positive bacterium classified as an opportunistic pathogen that can cause foodborne diarrhea and other intestinal diseases in humans and various animals. To date, there has been limited research on B. paranthracis, and there are few records of this bacterium being isolated from animal intestines. In this study, a strain named Qf-1 was isolated and purified from faecal samples of mink. Through culturomics, 16S rRNA gene sequencing, whole-genome sequencing, and average nucleotide identity (ANI) analysis, the strain was confirmed to be B. paranthracis. Whole-genome sequencing revealed that the strain has a genome size of 5.27 Mb, comprising one chromosome (5,224,739 bp) and one plasmid (51,964 bp). Functional annotation of its genome identified multiple potential pathogenic factors associated with pneumonia, including the key genes AsbD and AsbF, which facilitate bacterial colonisation of the lungs and trigger inflammatory responses, as well as EsxB and EsxL, which exacerbate lung inflammation and promote infection spread. Comparative genomics analysis revealed that this strain shares a close evolutionary relationship with previously reported B. paranthracis strains. The structure and function of the bacterial genes were analyzed in depth using multi-omics methods. Through mouse pathogenicity experiments, it was found that this bacterium may cause pneumonia and enteritis in mice. We predict that it may also pose a threat to the health of the mink. These research findings contribute to the establishment of a stable experimental model between pathogens and mink hosts, laying the foundation for further elucidating their pathogenicity and pathogenic mechanisms. This is of great significance for the diagnosis and prevention of bacterial diseases in mink in the future.