A Wohlfahrtiimonas chitiniclastica with a novel type of blaVEB-1-carrying plasmid isolated from a zebra in China.

Background: Wohlfahrtiimonas chitiniclastica is an emerging fly-borne zoonotic pathogen, which causes infections in immunocompromised patients and some animals. Herein, we reported a W. chitiniclastica BM-Y from a dead zebra in China. Methods: The complete genome sequencing of BM-Y showed that this isolate carried one chromosome and one novel type of bla_VEB-1-carrying plasmid. Detailed genetic dissection was applied to this plasmid to display the genetic environment of bla_VEB-1. Results: Three novel insertion sequence (IS) elements, namely ISWoch1, ISWoch2, and ISWochJ, were found in this plasmid. aadB, aacAl, and gcuG were located downstream of bla_VEB-1, composing a gene cassette array bla_VEB-1-aadB- aacA1-gcuG bracketed by an intact ISWoch1 and a truncated one, which was named the bla_VEB-1 region. The 5'-RACE experiments revealed that the transcription start site of the bla_VEB-1 region was located in the intact ISWoch1 and this IS provided a strong promoter for the bla_VEB-1 region. Conclusion: The spread of the bla_VEB-1-carrying plasmid might enhance the ability of W. chitiniclastica to survive under drug selection pressure and aggravate the difficulty in treating infections caused by bla_VEB-1-carrying W. chitiniclastica. To the best of our knowledge, this is the first report of the genetic characterization of a novel bla_VEB-1-carrying plasmid with new ISs from W. chitiniclastica. [ABSTRACT FROM AUTHOR]