Isolation and Whole Genome Sequencing Analysis of VB₁₂-Producing Lysinibacillus sphaericus Strain C5.1

In order to explore the mechanism for the production of vitamin B₁₂ (VB₁₂) by Lysinibacillus sphaericus C5.1, the whole genome of this stain was sequenced on the PacBio Sequel and Illumina NovaSeq PE150 platforms. Several bioinformatics methods were then used to assemble the sequence data obtained for gene prediction and functional annotation. The results showed that the genome of strain C5.1 consisted of one circular chromosome without plasmids and was 4690817 bp in length with an average GC content of 37.21%, and 4756 protein-encoding genes, 34 rRNAs, and 111 tRNAs were predicted. A total of 3095, 3182, 4374, and 397 genes were respectively matched to the Gene Ontology (GO), Clusters of Orthologous Groups (COG), Kyoto Encyclopedia of Genes and Genomes (KEGG), and Transporter Classification Database (TCDB). Furthermore, we found that the genome of strain C5.1 contained the genes encoding the key enzymes involved in the conversion of uroporphyrinogen Ⅲ to VB₁₂ . These results could provide an important foundation for studies on the metabolic pathways of L. sphaericus C5.1 during the fermentation of stinky tofu and also provide theoretical support for exploring the mechanism of vitamin B₁₂ biosynthesis in fermented foods.