To see the effects of tobramycin on Pseudomonas aeruginosa under anaerboc lethal conditions. RNA was isolated from 5 biological repeats of P.aeruginosa grown in cationic adjusted mueller hinton broth containing 15mM KNO3 and 5 biological repeats of P.aeruginosa grown in cationic adjusted mueller hinton broth containing 15mM KNO3 after being treated with 20 ug/ml tobramycin for 30 minutes.