Purification and properties of a new psychrophilic metalloprotease (Fpp2) in the fish pathogen Flavobacterium psychrophilum
- 作者：Secades ; P. ; Alvarez ; B. ; Guijarro ; J.A.
- 关键词：Metalloprotease ; Psychrophilic ; Fish ; Pathogen ; Flavobacterium psychrophilum
- 刊名：FEMS Microbiology Letters
- 出版年：2003
- 期刊代码：34_03781097
- 类别：imm
- 出版时间：September 26, 2003
- 卷：226
- 期：2
- 页码：273-279
- 文件大小：301 K
摘要
To go further into the characterization of the proteolysis exocellular system of the salmonid pathogen Flavobacterium psychrophilum, the purification and characterization of a novel protease designated Fpp2 (F. psychrophilum protease 2) was undertaken. A protease (Fpp2) hydrolyzing azocasein was purified. The Fpp2 can be defined as a metalloprotease, it had an estimated molecular mass of 62 kDa with calcium playing an important role in the thermostability of the enzyme. Proteolytic activity was optimal at pH 6.0–7.0 and 24°C and activation energy for the hydrolysis of azocasein was determined to be 5.4 kcal mol−1, being inactive at temperatures above 42°C. All these results are characteristic of ‘cold adapted enzymes’. Fpp2 proved to be a broad range hydrolytic enzyme because in optimal conditions it was able to hydrolyze matrix and muscular proteins. It can be concluded that the Fpp1, a previously characterized 55 kDa metalloprotease, and the Fpp2 protease were produced under different physiological conditions and were immunologically as well as biochemically different.