Purification and Characterization of an Extracellular Alkaline Protease from Aspergillus niger C-15.
10.4489/MYCO.2004.32.2.074
- Author:
Jeong Dong KIM
1
Author Information
1. Department of Life Science, Hanyang University, Seoul 139-701, Korea. jdkim@hanyang.ac.kr
- Publication Type:Original Article
- Keywords:
Alkaline protease;
Aspergillus niger;
Metalloprotease;
Protease
- MeSH:
Aspergillus niger*;
Aspergillus*;
Chromatography, Gel;
Chromatography, Ion Exchange;
Edetic Acid;
Glycerol;
Hydrogen-Ion Concentration;
Mannitol;
Mercuric Chloride;
Molecular Weight;
Sorbitol;
Xylitol
- From:Mycobiology
2004;32(2):74-78
- CountryRepublic of Korea
- Language:English
-
Abstract:
An alkaline protease produced by Aspergillus niger C-15 was purified and characterized. The enzyme was purified 19.41-fold with a specific activity of 74150 U/mg and a recovery of 34.4% by gel filtration and ion exchange chromatography. The molecular weight of the enzyme was estimated to be 34 kDa. The optimum pH and temperature for the protease activity were pH 8.0 and 60degrees C, respectively. The enzyme activity inhibited by EDTA suggests that the preparation contains a metalloprotease. The enzyme activity of the metalloprotease was completely inhibited by 5 mM HgCl2 and FeCl3, while partially inhibited by CuSO4, and MnCl2. When polyols such as glycerol, mannitol, sorbitol and xylitol, were added to the reaction medium, most polyols tested enhanced protease activity. Especially, glycerol showed the highest effect. The alkaline metalloprotease was stable at high temperature and retained more than 90% of the initial activity at 60degrees C and 86.4% under addition of glycerol.
