Genomic characterization of a multidrug-resistant Mycoplasma hominis recovered from a synovial fluid sample in China

Abstract Objectives Mycoplasma hominis is one of the smallest free-living opportunistic human pathogen responsible for a diverse range of infections. However, our knowledge regarding the genetic and pathogenic mechanisms of M. hominis is still very limited. This study aimed to investigate the genomic features of a multidrug-resistant M. hominis isolate recovered from a synovial fluid sample in China. Methods Antimicrobial susceptibility of M. hominis MH-1 was determined by the broth microdilution method. Genomic DNA was extracted and sequenced using the Illumina HiSeq X Ten platform. De novo genome assembly was performed using SPAdes and the draft genome was annotated using the NCBI Prokaryotic Genome Annotation Pipeline. The core genome single nucleotide polymorphism (cgSNP) analysis between M. hominis MH-1 and all M. hominis strains retrieved from NCBI GenBank database was performed by BacWGSTdb server. Results Antimicrobial susceptibility testing showed that M. hominis MH-1 was resistant to macrolides and fluoroquinolones. The genome size was calculated as 720,262 bp, with 608 protein-coding sequences and GC content of 26.8%. Several antimicrobial resistance genes, virulence genes, genomic islands and insertion sequences were identified in the genome sequence. Phylogenetic analysis showed that these strains retrieved from NCBI as well as M. hominis MH-1 were not epidemiologically related. The closest relative of M. hominis MH-1 was recovered from the USA, which differed by 5898 SNPs. Conclusion Our study report the first genome sequence of a multidrug-resistant M. hominis isolate in China. These data may help to understand the genomic features and antimicrobial resistance mechanisms of this pathogen.