The operon encoding SubAB, a novel cytotoxin, is present in shiga toxin-producing Escherichia coli isolates from the United States.

@article{Khaitan2007TheOE,
  title={The operon encoding SubAB, a novel cytotoxin, is present in shiga toxin-producing Escherichia coli isolates from the United States.},
  author={Alka Khaitan and Dakshina M. Jandhyala and Cheleste M. Thorpe and Jenny M Ritchie and Adrienne W Paton},
  journal={Journal of clinical microbiology},
  year={2007},
  volume={45 4},
  pages={1374-5}
}