Journal of Basic Microbiology 2012, 52, 1 – 8 1 © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim www.jbm-journal.com Research Paper Simultaneous production of alkaline lipase and protease by antibiotic and heavy metal tolerant Pseudomonas aeruginosa Deepali Bisht, Santosh Kumar Yadav, Pallavi Gautam and Nandan Singh Darmwal Centre of Excellence, Department of Microbiology, Dr. Ram Manohar Lohia Avadh University, Faizabad, U.P., India 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 phylo- genetic 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. Keywords: Pseudomonas aeruginosa / 16S rDNA / Lipase / Protease / Heavy metal resistant Received: March 17, 2012; accepted: May 29, 2012 DOI 10.1002/jobm.201200157 Introduction * Microorganisms usually form a robust community capable of surviving and functioning under extreme environmental conditions [1]. The structural and func- tional diversity of microbes could be the primary and richest source of the natural resources that can be util- ized in both environmental and biotechnological appli- cations. Lipids constitute a large part of the earth’s biomass and lipolytic enzymes play an important role in the turnover of these water insoluble compounds. Lipases (triacylglycerol acylhydrolases, EC 3.1.1.3), are ubiqui- tous in nature and have immense application in phar- maceuticals, textiles, food, medical, and chemical industries [2], cosmetics, detergent, paper and envi- ronment [3, 4] and are also used for resolution of race- mic mixtures to produce optically active compounds Correspondence: Nandan Singh Darmwal, Centre of Excellence, Department of Microbiology, Dr. Ram Manohar Lohia Avadh University, Faizabad, Uttar Pradesh, India E-mail: drnsdarmwal@gmail.com Phone: +91 9452277199 Fax: +91 5278 246330 [5]. On the other hand, alkaline proteases execute a large variety of complex physiological, metabolic and regulatory functions which is evident from its occur- rence in all forms of living organisms [6]. Moreover, protease constitutes one of the most important groups of industrial enzymes that account for about 60% of the total worldwide enzymes sales [7]. They can hydro- lyze proteins into short peptide or amino acids and have a wide range of applications, particularly in the detergent, food, pharmaceutical leather and chemical industries [8]. Organisms secreting both lipase and protease are more valuable especially for laundry applications where a cocktail of enzymes is added to the detergent for im- proving its quality [9]. Various processes like bating of leather and cleaning of slaughter house equipment also insist a mixture of lipase and protease [10]. However, the high production cost is one of the limiting factor for industrial use of lipase and protease individually. Therefore, the preparations comprising both the activi- ties collectively and lipase not being susceptible to hy- drolysis by protease will have better applicability. A number of reports are available on the production of