Identification Of Toxin-Antitoxin Systems In Pseudomas Aeruginosa

Toxin-antitoxin (TA) systems allow free-living bacteria to respond to environmental stresses by regulating toxin activity at the levels of transcription and translation. The toxin and the antitoxin form stable complexes. When disrupted, the toxin is free to target key processes within the cell, resulting in growth inhibition or death. TA systems have been extensively studied in the model organism Escherichia coli. However, current research has not elucidated any TA systems in the nosocomial pathogen Pseudomonas aeruginosa. The P. aeruginosa genome was screened and gene pair PA0124/0125 was predicted to be a TA system by the identification of two open reading frames in an operon. The predicted toxin gene, PA0124, was isolated, inserted into a shuttle vector, and overexpressed in E. coli and P. aeruginosa. The effect of the toxin gene on the growth of P. aeruginosa was observed as the transformed bacteria were grown on agar plates. There appeared to be little or no difference between the bacterial growth with or without the gene insertion. Future research will focus on isolating and expressing other predicted toxins in P. aeruginosa