Corynebacterium glutamicum was   isolated in  our  microbiology research lab. Thialysine resistant mutants were developed by treating with ultraviolet radiation. The most potent resistant mutant was further treated by U.V radiation. As a result 42 different threonine-auxotrophic mutants were developed, isolated and screened for lysine production. The mos tpotent mutant produced 18.3  mg/mi lysine in  shake  flask fermentation after 6th day  of incubation (temp.30°C, 200 rpm, pH 7.5). The lysine production increased to 26.2 mg/mi in strirrer tank fermenter on 4ht  day of fermentation (temp 30°C, pH 7.4, agitation 500 rpm, acration 1 vvm).


A H SHAH ,G M KHAN ,A HAMEED ,