Abstract
Alkaline proteases, named VapT and VapK, from Gram-negative alkalophilic Vibrio metschnikovii strain RH530 were purified and characterized. Both enzymes had optimum pH and temperature of 10. 5 and 60 °C, respectively. VapT and VapK retained 40 % and 80 %, respectively, of their initial activities at pH 12 after 24-h incubation at 25 °C. The half-lives of VapT and VapK were 10 min and 24 min, respectively, at pH 8 and 60 °C. Addition of Ca2+ extended their half-lives more than 20 fold. VapT and VapK retained over 30 % and 90 %, respectively, of their activities in the presence of 5 % SDS and 8 M urea. Analysis of amino acid composition showed that VapT contained seven cysteine residues and VapK did two. The N-terminal amino acid sequences of the proteases were determined and compared with those of Bacillus licheniformis subtilisin Carlsberg, Vibrio alginolyticus exoprotease A, and Tritirachium album proteinase K.
Original language | English (US) |
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Pages (from-to) | 413-418 |
Number of pages | 6 |
Journal | Biotechnology Letters |
Volume | 16 |
Issue number | 4 |
DOIs | |
State | Published - Apr 1994 |
Externally published | Yes |
ASJC Scopus subject areas
- Microbiology
- Applied Microbiology and Biotechnology
- Bioengineering
- Biotechnology