Induction of mutation in Bacillus subtilis lipase gene using error-prone PCR
Journal Title: Jundishapur Journal of Microbiology - Year 2011, Vol 4, Issue 3
Abstract
Introduction and objective: Directed evolution is an incredibly powerful tool for altering the properties of enzymes. This approach uses a “sloppy” version of PCR, in which the polymerase has a fairly high error rate to amplify the wild-type sequence. The aim of this study was to produce the Bacillus subtilis mutant lipase which can be active at low temperatures using the error-prone PCR method. Materials and methods: The pGEM-T vector containing B. subtilis lipase gene was transformed into the Escherichia coli DH5α. The lipase gene was mutated using the error-prone PCR technique. Screening of the mutants was carried out using both microtiter and Luria-Bertani plates containing 1% tributyrin and 100mg/ml ampicillin. Ten out of 1300 clones which showed the lipase activity at 10ºC were isolated. Among them, three desirable mutants named pFJK1, pFJK2 and pFJK3 were selected. Clones containing the wild type and the mutated lipase gene were both purified and characterized. The enzyme assay at different temperatures was carried out. Results: The optimum temperature for the activity of lipase was achieved at 10ºС and 30ºС for the mutants and control, respectively. The relative enzyme activity of pFJK1, pFJK2 and pFJK3 at 10ºC was more than two times of their activity at 30ºC. The enzyme retained 70% of its activity at 10ºС and there was a drastic decline in enzyme activity at 50ºС. Conclusion: Based on the present findings, the enzyme was characterized as a cold adapted lipase which showed the highest activity at 10ºС. Significance and impact of the study: Cold adapted lipase can be developed for industrial applications such as additives in detergents.
Authors and Affiliations
Farzaneh Aboualizadeh, Jagdeep Kaur, Abbas Behzad-Behbahani, Bahman Khalvati
Antimicrobial activity of essential oils of Ferulago angulata subsp. carduchorum
Introduction and objective: Ferulago angulata is an important medicinal plant of Iran. The essential oil of seeds aerial parts of this plant contains variety of components with different therapeutical effects. The purpos...
The enhancement of methyl tertiary butyl ether oxidation by Gordonia in the presence of nanosilver and nitrate
Introduction and objective: Several Gram-positive and Gram-negative bacteria isolated from methyl tertiary butyl ether (MTBE) reached soil. Among them one Gram-positive, oxidize positive, partial acid fast, which had str...
A study of rdxA gene deletion in metronidazole resistant and sensitive Helicobacter pylori isolates in Kerman, Iran
Introduction and objective: Metronidazole (Mtz) resistance in Helicobacter pylori has been found to be associated with mutations in rdxA, a gene encoding an oxygen insensitive NADPH nitroreductase, and enhanced by mutati...
Effect of various concentrations of Crocus sativus and Cannabis sativa extracts on luminescent biosensor Escherichia coli SM10 S1
Introduction and objective: The potential risk of application of high dosage of traditional medicinal plants has not been fully understood. Appropriate microbial biosensors have been constructed for monitoring the toxici...
Detection of Salmonella strain by rapid-cycle multiplex PCR
Introduction and objective: Salmonellosis is responsible for large numbers of infections in both humans and animals. Conventional methods of isolation of Salmonella strains take 4-7 days to complete and are therefore lab...