Systemic Mutagenesis of Bacillus sp. APR-4 for Enhanced Production of Thermostable and Alkaline Protease

Author: Neha Thakur*, Tek Chand Bhalla** and Dinesh Kumar*

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Abstract

Proteases are the most important group of industrial enzymes and constitute 60% of the total worldwide enzyme sales. Strain improvement is an essential part of enhanced production of enzymes from wild strain available. In present study a wild strain Bacillus sp. APR-4 producing 2578±0.1 U/ml protease in GYP medium at pH 7.0 after 40h incubation at 50oC was used for random mutagenesis by physical, chemical and combined method to obtain a hyper producer mutant. The physical mutagenesis using UV-radiation resulted in 32.4% rate of survival of wild strain after 90 minute exposure which decreased gradually to 0% after 150 minutes. Isolate UV8 showed maximum zone of hydrolysis (13±0.1mm) and enzyme activity (2599±2.6U/ml). The chemical mutagenesis of Bacillus sp. APR-4 resulted in 28% survival rate after 90 min exposure with EMS at 200 µg/ml concentration. In EtBr (150 µg /ml), MMS (150 µg/ml), and FU (200 µg/ml) after 90 minutes exposure the survival rate was 38%, 20% and 25% respec

Keywords

Bacillus sp. APR-4, Thermostable alkaline protease, Physical, Chemical and Combined mutagenesis

Conclusion

In the present study the improvement of Bacillus sp. APR-4 isolated earlier was carried out through systemic mutagenesis using physical, chemical and combined mutagens to isolate a hyper protease producer strain. For this UV- radiation was used as physical mutagen, and EMS, EtBr, FU and MMS were used as chemical mutagens individually. The protease activity increased to 2599±2.6U/ml in mutant (UV8) with UV exposure alone. On the other hand chemical mutagens increased this production to 2678±1.5U/ml and rate of survival get decreased with increased exposure time after treatment of wild strain with different chemical mutagen. Further the UV optimized mutant UV8 was treated with individual chemical mutagens at different concentration to see the combined mutagenesis effect on protease production. However, subsequent treatment of UV optimized mutant with chemical mutagen, further increased this production to 3209±4.0 U/ml in mutant UVEMS52. This mutant showed 1.24-fold increase in enz

References

A continuous effort is being made on search for new range of enzymes to meet the increasing industrial demands for enzymes capable to withstand extreme industrial process conditions (Zhang and Kim, 2010). The current status of enzyme market is currently $5.1 billion and is expected to rise upto 6.3% annually (Cui et al., 2015). Proteases are among one of the three largest groups of industrial enzymes and account for 60 % of the total enzyme sales (Zambare et al., 2011). Proteases possess a wide range of industrial applications, mainly in detergents, leather processing, food processing, bioactive peptide synthesis, metal recovery, medical purposes, chemical industries, as well as in waste treatment (Lopez-Otin and Bond, 2008). Despite massive use of enzymes in biotechnological applications, there is still significant need for improvement of enzymes in industrial processes. Most of the industrial strains currently used for the production of novel compounds are obtained from their natura

How to cite this article

Neha Thakur, Tek Chand Bhalla and Dinesh Kumar (2017). Systemic Mutagenesis of Bacillus sp. APR-4 for Enhanced Production of Thermostable and Alkaline Protease ,Biological Forum – An International Journal 9(2): 54-60.