Increasing the thermostability of the neutral proteinase of Bacillus stearothermophilus by improvement of internal hydrogen-bonding.
In an attempt to increase the thermostability of the neutral proteinase of Bacillus stearothermophilus the buried Ala-170 was replaced by serine. Molecular-dynamics simulations showed that Ser-170 stabilizes the enzyme by formation of an internal hydrogen bond. In addition, the hydroxy group of Ser-170 could contribute to stability by filling an internal cavity. After the introduction of the mutation, using site-directed-mutagenesis techniques, an increase in stability of 0.7 +/- 0.1 degrees C was obtained.
Eijsink
V G
VG
Department of Molecular Genetics, University of Groningen, Haren, The Netherlands.
Vriend
G
G
Van der Zee
J R
JR
Van den Burg
B
B
Venema
G
G
D000409:Alanine / Q000235:genetics; D001483:Base Sequence; D004269:DNA, Bacterial; D004795:Enzyme Stability; D001411:Geobacillus stearothermophilus / Q000201:enzymology*; D006358:Hot Temperature; D006859:Hydrogen / Q000737:chemistry*; D008666:Metalloendopeptidases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D012694:Serine / Q000235:genetics
D004269:DNA, Bacterial; D012694:Serine; D006859:Hydrogen; D008666:Metalloendopeptidases; C044194:microbial metalloproteinases; D000409:Alanine