Open AccessEnhancement of thermostability and resistance against autolysis in a zinc metalloprotease
Author(s) -
Shirdel S. Akram,
Khajeh Khosro,
Asghari S. Mohsen,
KarbalaeiHeidari HamidReza
Publication year - 2014
Publication title -
engineering in life sciences
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.547
H-Index - 57
eISSN - 1618-2863
pISSN - 1618-0240
DOI - 10.1002/elsc.201200218
Subject(s) - thermostability , autolysis (biology) , metalloproteinase , zinc , resistance (ecology) , chemistry , biochemistry , biology , enzyme , organic chemistry , ecology
Neutral proteases are inactivated at higher temperatures because of autolysis. It appears that autolysis involves some specific solvent‐exposed regions that become prone to local unfolding as temperature increases. Accordingly, we designed surface‐located mutations at the N‐terminal loops ( A 56 P and T 73 F ) of the neutral protease from S alinivibrio proteolyticus and compared the thermostability and autolysis as well as structural properties of wild‐type ( WT ) and mutant proteins. Circular dichroism in far‐ UV region and intrinsic fluorescence data indicated that compactness of protein increases upon mutation. It was revealed that the catalytic efficiency (k cat /K m ) of the enzyme is improved in mutants and optimum temperature of mutants increases relative to WT enzyme. It was also shown that the mutant enzymes are more resistant against autolysis and their thermostability and kinetic parameters are also changed compared to WT protein. This study shows that the stability of enzyme against autolysis and temperature may be increased even by changing only a single amino acid, which in turn is important from application point of view.