Purification and characterization of a surfactant-stable high-alkaline protease from Bacillus sp. B001

• DOI: 10.1016/j.biortech.2010.03.130
• Publication Date: 2010-04-23T09:01:13Z
• Authors: Aihua Deng; Jie Wu; Yun Zhang; Guoqiang Zhang; Tingyi Wen
• Keywords: Enzyme Activation; Surface-Active Agents; 0303 health sciences; 03 medical and health sciences; Bacterial Proteins; Species Specificity; Endopeptidases; Enzyme Stability; Bacillus

The newly isolated alkalophilic Bacillus sp. B001 produced a high level of proteolytic activity (34277 U/mL) when grown in production medium, and a 28 kDa protease, designated AprB, was purified from the culture supernatant. Partial amino acid sequences were obtained by tandem mass spectrometry (MS/MS) and a pair of degenerate primers was developed to amplify a 467-bp genomic sequence. The observed and predicted amino acid sequences showed similarity with sequences of high-alkaline proteases from Bacillusclausii, Bacillusalcalophilus, and Bacillus lentus. High stability of AprB towards surfactants and oxidizing agents, an optimal pH of 10.0, and an optimal temperature of 60 degrees C suggest that this high-alkaline protease has potential applications for various industrial processes.