Please use this identifier to cite or link to this item:
|Title:||Isolation of a halophilic Virgibacillus sp. EMB13: Characterization of its protease for detergent application|
Khare, S K
|Keywords:||Halophiles;Organic solvent stable;Protease;Virgibacillus sp.|
|Abstract:||Isolation and characterization of a moderately halophilic bacterium, Virgibacillus sp. EMB13, from the West coast of India has been described in the present study. It produced five different extracellular proteases. Conditions were optimized for maximum protease production. Under optimized conditions, viz., a medium containing (%, w/v) yeast extract, 1.0; peptone, 0.5; mannitol, 0.5; NaCl, 0.5; KCl, 1.0; CaCl2, 0.03 and MgSO4, 0.04 with pH 8, it produced 270 U protease mL-1. The protease was partially purified by DEAE ion exchange and Sephadex G-75 gel filtration chromatography. The purified preparation contained two unseparated proteases with apparent molecular masses of 49 and 54 kDa, respectively. The preparation was stable at different concentrations of NaCl (0-15%, w/v) and pH range 6.0-12.0. It exhibited maximal activity at pH 7.5, temperature 50°C and 1% (w/v) NaCl. The Km and Vmax values towards casein were 7.5 mg mL-1 and 156.25 µg min-1 mL-1, respectively. Inhibition of their proteolytic activity by EDTA and 1,10-phenanthroline indicated them to be metalloprotease in nature. The proteases exhibited remarkable stability in the presence of salt and organic solvents. These properties enable them for novel applications in non-aqueous enzymology and as an additive in detergent formulations.|
|ISSN:||0975-0967 (Online); 0972-5849 (Print)|
|Appears in Collections:||IJBT Vol.11(4) [October 2012]|
Items in NOPR are protected by copyright, with all rights reserved, unless otherwise indicated.