Simultaneous production of alkaline lipase and protease by antibiotic and heavy metal tolerant Pseudomonas aeruginosa.

An efficient bacterial strain capable of simultaneous production of lipase and protease in a single production medium was isolated. Thirty six bacterial strains, isolated from diverse habitats, were screened for their lipolytic and proteolytic activity. Of these, only one bacterial strain was found to be lipase and protease producer. The 16S rDNA sequencing and phylogenetic analyses revealed that strain (NSD-09) was in close identity to Pseudomonas aeruginosa. The maximum lipase (221.4 U/ml) and protease (187.9 U/ml) activities were obtained after 28 and 24 h of incubation, respectively at pH 9.0 and 37 °C. Castor oil and wheat bran were found to be the best substrate for lipase and protease production, respectively. The strain also exhibited high tolerance to lead (1450 µg/ml) and chromium (1000 µg/ml) in agar plates. It also showed tolerance to other heavy metals, such as Co(+2) , Zn(+2) , Hg(+2) , Ni(+2) and Cd(+2) . Therefore, this strain has scope for tailing bioremediation. Presumably, this is the first attempt on P. aeruginosa to explore its potential for both industrial and environmental applications.