Identification of amino acids related to catalytic function of Sulfolobus solfataricus P1 carboxylesterase by site-directed mutagenesis and molecular modeling.

ABSTRACT: The archaeon Sulfolobus solfataricus P1 carboxylesterase is a thermostable enzyme with a molecular mass of 33.5 kDa belonging to the mammalian hormone-sensitive lipase (HSL) family. In our previous study, we purified the enzyme and suggested the expected amino acids related to its catalysis by chemical modification and a sequence homology search. For further validating these amino acids in this study, we modified them using site-directed mutagenesis and examined the activity of the mutant enzymes using spectrophotometric analysis and then estimated by homology modeling and fluorescence analysis. As a result, it was identified that Ser151, Asp244, and His274 consist of a catalytic triad, and Gly80, Gly81, and Ala152 compose an oxyanion hole of the enzyme. In addition, it was also determined

SUBMITTER: Choi YH 

PROVIDER: S-EPMC5070724 | biostudies-literature | 2016 Jun

REPOSITORIES: biostudies-literature