Engineering enhanced thermostability into the Geobacillus pallidus nitrile hydratase.

ABSTRACT: Nitrile hydratases (NHases) are important biocatalysts for the enzymatic conversion of nitriles to industrially-important amides such as acrylamide and nicotinamide. Although thermostability in this enzyme class is generally low, there is not sufficient understanding of its basis for rational enzyme design. The gene expressing the Co-type NHase from the moderate thermophile, Geobacillus pallidus RAPc8 (NRRL B-59396), was subjected to random mutagenesis. Four mutants were selected that were 3 to 15-fold more thermostable than the wild-type NHase, resulting in a 3.4-7.6 ​kJ/mol increase in the activation energy of thermal inactivation at 63 ​°C. High resolution X-ray crystal structures (1.15-1.80 ​Å) were obtained of the wild-type and four mutant enzymes. Mutant 9E, with a resolution

SUBMITTER: Van Wyk JC 

PROVIDER: S-EPMC9465369 | biostudies-literature | 2022

REPOSITORIES: biostudies-literature