title: Purification and characterization of a novel extracellular alkaline protease from Cellulomonas bogoriensis.
abstract: An extracellular alkaline protease produced by the alkali-tolerant Cellulomonas bogoriensis was purified by a combination of ammonium sulfate precipitation and cation exchange chromatography. The purity of the protease was detected by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and its molecular weight was confirmed to be 18.3 kDa. The enzyme showed optimum activity at 60 °C and pH 11. The stability of the protease was maintained at a wide temperature range of 4-60 °C and pH range of 3-12. Irreversible inhibition of the enzyme activity by phenylmethylsulfonyl fluoride and tosyl-l-phenylalanine chloromethyl ketone demonstrated that the purified enzyme is a chymotrypsin of the serine protease family. The Km and Vmax of the protease activity on casein were 19.2 mg/mL and 25000 μg/min/mg, respectively. The broad substrate specificity and remarkable stability in the presence of organic solvents, salt, and commercial detergents, as well as its excellent stain removal and dehairing capability, make the purified alkaline protease a promising candidate for industrial applications.
authors: School of Life Science, Northeast Normal University, Changchun 130024, China.
authors: Fan
authors: F
authors: Li
authors: School of Life Science, Northeast Normal University, Changchun 130024, China.
authors: Liyuan
authors: L
authors: Yang
authors: School of Life Science, Northeast Normal University, Changchun 130024, China.
authors: Xue
authors: X
authors: Lv
authors: School of Life Science, Northeast Normal University, Changchun 130024, China.
authors: Dongbo
authors: D
authors: Liu
authors: School of Life Science, Northeast Normal University, Changchun 130024, China.
authors: Hongmei
authors: H
authors: Xia
authors: School of Life Science, Northeast Normal University, Changchun 130024, China. Electronic address: Chens093@nenu.edu.cn.
authors: Shan
authors: S
authors: Chen
mesh_terms: D000645:Ammonium Sulfate / Q000737:chemistry; D001426:Bacterial Proteins / Q000037:antagonists & inhibitors / Q000737:chemistry* / Q000302:isolation & purification*; D040143:Cellulomonas / Q000201:enzymology*; D010450:Endopeptidases / Q000737:chemistry* / Q000302:isolation & purification*; D004795:Enzyme Stability; D007700:Kinetics; D010664:Phenylmethylsulfonyl Fluoride / Q000494:pharmacology; D012997:Solvents / Q000737:chemistry
chemical_list: D001426:Bacterial Proteins; D012997:Solvents; D010664:Phenylmethylsulfonyl Fluoride; D010450:Endopeptidases; C087822:alkaline protease; D000645:Ammonium Sulfate
keywords: Alkaline protease; Cellulomonas bogoriensis; Chymotrypsin; Serine protease