Genome analysis and safety assessment of Achromobacter marplatensis strain YKS2 strain isolated from the rumen of Yaks in China

Abstract

Abstract Achromobacter marplatensis strain YKS2 isolated from the Yak rumen has a feature of producing cellulose. This study aims to analyze the genome and safety of strainYKS2 in vivo considering its future research and application prospects. The genome of strain YKS2 was sequenced and used for genomic in silico studies. The administration of strain YKS2 with three doses was carried out on mice for 3 days of oral and 7 days of clinical observation tests. The BW, FI, organ indices, gut microbiota, and histological appearances of organs & intestines, along with hematological parameters and serum biochemistry were measured on mice. The chromosome size of strain YKS2 was 5 918 133 bp with GC content of 89.82%. The strain was component of 6 058 coding genes and had multiple functional genes, but no plasmids. The mice in all groups were alive, with good mental states and functional activities. Compared with the control group, there was no significant difference in the three dose groups on BW, FI, hematological parameters (WBC, LYM, etc.) and serum biochemistry (ALB, ALT, etc.). No abnormalities were observed in main visceral organs, intestinal tissue and V/C value in groups. However the IEL number of duodenum and gut microbiota diversity (Shannon index) in the high-dose group was significantly higher than in the control group (p < 0.05). Besides, the low dose of strain YKS2 also significantly affected the bacterial abundance of firmicutes, actinobacteria and desulphurizing bacteroidetes at the phylum. There was no significant effect at genus levels in groups. In a word, the study provided the genome and potential functional genes of strain YKS2, which is beneficial to understand the features of the A. marplatensis strain, and proved train YKS2 without acute toxicity to mice. However, a long-term feeding toxicity experiment in vivo should be performed to further ensure its potential application value strain in the animal industry.