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Increasing the thermostability of the neutral proteinase of Bacillus stearothermophilus by improvement of internal hydrogen-bonding.

ABSTRACT: 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.

SUBMITTER: Eijsink VG

PROVIDER: S-EPMC1132834 | biostudies-other | 1992 Jul

REPOSITORIES: biostudies-other

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Thermostability enhancement and change in starch hydrolysis profile of the maltohexaose-forming amylase of Bacillus stearothermophilus US100 strain.

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