Open AccessExtracellular alkaline protease from Bacillus licheniformis NCIM‐2042: Improving enzyme activity assay and characterization
Author(s) -
Bhunia Biswanath,
Dutta Debjani,
Chaudhuri Surabhi
Publication year - 2011
Publication title -
engineering in life sciences
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.547
H-Index - 57
eISSN - 1618-2863
pISSN - 1618-0240
DOI - 10.1002/elsc.201000020
Subject(s) - bacillus licheniformis , alkaline protease , extracellular , enzyme , protease , chemistry , biochemistry , microbiology and biotechnology , biology , bacillus subtilis , bacteria , genetics
Abstract Optimization of enzyme assay conditions for alkaline protease from Bacillus licheniformis NCIM‐2042 was carried out by a statistical approach. Four key determinants such as pH, temperature, buffer concentration, and incubation time were optimized by response surface methodology using rotatable central composite design. Maximum enzyme activity was found to be at pH 9.0, temperature 75°C in phosphate buffer (50 mM) when incubated for 10 min. Protease was stable over a broad range of pH 6.0–12.0 and it was stable at 50°C for 1 h. The protease was completely inhibited by PMSF (5 mM), suggesting that the enzyme is a serine alkaline protease. This enzyme had good stability in the presence of H 2 O 2 , SDS, Triton X‐100, and retained more than 88% of its initial activity after preincubation for 30 min at room temperature in the presence of 25% v/v DMSO, methanol, ethanol, ACN, and 2‐propanol.