Maintenance of the Shigella sonnei Virulence Plasmid Is Dependent on Its Repertoire and Amino Acid Sequence of Toxin-Antitoxin Systems.

ABSTRACT: Shigella sonnei is a major cause of bacillary dysentery and an increasing concern due to the spread of multidrug resistance. S. sonnei harbors pINV, an ∼210 kb plasmid that encodes a type III secretion system (T3SS), which is essential for virulence. During growth in the laboratory, avirulence arises spontaneously in S. sonnei at high frequency, hampering studies on and vaccine development against this important pathogen. Here, we investigated the molecular basis for the emergence of avirulence in S. sonnei and showed that avirulence mainly results from pINV loss, which is consistent with previous findings. Ancestral deletions have led to the loss from S. sonnei pINV of two toxin-antitoxin (TA) systems involved in plasmid maintenance, CcdAB and GmvAT, which are found on pINV in Shigella fl

SUBMITTER: Martyn JE 

PROVIDER: S-EPMC8923223 | biostudies-literature | 2022 Mar

REPOSITORIES: biostudies-literature