Pathogenic Characteristics and Genomic Analysis of a Rare Serotype Salmonella enterica Serovar Moualine Isolated from the Blood.

BACKGROUND

Salmonella is composed of a wide variety of serovars that cause human self-limited gastrointestinal illnesses or invasive infections. Most of the Salmonella strains of clinical isolates belong to the A - F group. In December 2012, a case of invasive infection was caused by a rare Salmonella, Salmonella enterica serovar Moualine (S. Moualine), identified as 047 outside of groups A - F, which was easily missed or misreported. The goal is to ex-plore clinical symptoms and therapies of blood infection caused by S. Moualine and to provide theoretical basis and molecular level date for Salmonella research by analyzing pathogenic characteristics and genome information of S. Moualine.

METHODS

The S. Moualine genome was sequenced using a PacBio RS II platform and Illumina HiSeq 4000 platform and analysis for serotyping serovars, ST types, the characterization of antibiotic resistance, virulence and phylogeny.

RESULTS

The clinical symptoms were mainly irregular recurrent fever, lasting 1 - 3 weeks, with mild gastrointestinal symptoms. The genome size of S. Moualine was 4,611,151 bp, the serotype was 047 (+), Hy (+), H1,6 (+), and multilocus sequence typing analysis was ST3038. S. Moualine contains the majority of virulence genes. Interestingly, S. Moualine also harbors the rck and Typhi colonization factor (tcf) genes, which may play a role in invasive infection. S. Moualine encodes 17 Salmonella pathogenicity islands and is potentially dangerous to human health. Both phenotypic and genomic characterizations have demonstrated that S. Moualine generally showed low antimicrobial resistance potential.

CONCLUSIONS

There were few reports on S. Moualine. According to clinical symptoms and genetic analysis, S. Moualine was predicted to be a highly virulent bacteria and was also potentially dangerous to health of humans. This study highlights that the transparency of global surveillance genomic data could accelerate the understanding of the virulence and antimicrobial resistance makeup of a previously unknown threat.