Open AccessExtruction of keratinase from the local isolate Bacillus licheniformis and partially purified and characterized
Author(s) -
Rasha T. Abdullah,
Abdulkareem Jasim Hashim,
Jasim M. Karhout
Publication year - 2009
Publication title -
maǧallaẗ markaz buḥūṯ al-taqniyyaẗ al-aḥyāʾiyyaẗ
Language(s) - English
Resource type - Journals
eISSN - 2708-1370
pISSN - 1815-1140
DOI - 10.24126/jobrc.2009.3.2.68
Subject(s) - keratinase , bacillus licheniformis , casein , chemistry , enzyme , enzyme assay , chromatography , pmsf , ammonium , gelatin , nuclear chemistry , substrate (aquarium) , metal ions in aqueous solution , biochemistry , metal , bacillus subtilis , biology , bacteria , organic chemistry , ecology , genetics
The keratinase produced from local isolate Bacillus licheniformis was purified by two steps included precipitation by ammonium sulphate with 40% saturation; followed by ion exchange using CM-Cellulose column. The enzyme was purified to 12.6 times in the last step with an enzyme yield of 17%. Enzyme characterization results indicated that: The optimal pH for enzyme activity was 7.5 and it was stable at 7-9.5. The optimal temperature for enzyme activity was 50°C and it was stable for 30 min at 25-45 °C. Substrate specifity was tested using casein, Bovine serum albumin, gelatin, hooves, human hair, chicken feathers and wool; higher specifity was recorded using casein gave 0.6 unit /ml. The enzyme was inhibited by PMSF and metal ions like Hg+2, Fe+2, Cu+2 and Mn+2, and activated by Ca+2, Mg+2, Zn+2and Al+3.