Control of oligomeric enzyme thermostability by protein engineering Academic Article Article uri icon


MeSH Major

  • National Institutes of Health (U.S.)
  • Translational Medical Research


  • The ability to control the resistance of an enzyme to inactivation due to exposure to elevated temperatures is essential for the understanding of thermophilic behavior and for developing rational approaches to enzyme stabilization. By means of site-directed mutagenesis, point mutations have been engineered in the dimeric enzyme yeast triosephosphate isomerase that improve its thermostability. Cumulative replacement of asparagine residues at the subunit interface by residues resistant to heat-induced deterioration and approximating the geometry of asparagine (Asn-14----Thr-14 and Asn-78----Ile-78) nearly doubled the half-life of the enzyme at 100 degrees C, pH 6. Moreover, in an attempt to model the deleterious effects of deamidation, we show that replacement of interfacial Asn-78 by an aspartic acid residue increases the rate constant of irreversible thermal inactivation, drastically decreases the reversible transition temperature, and reduces the stability against dilution-induced dissociation.

publication date

  • May 12, 1987



  • Academic Article


Digital Object Identifier (DOI)

  • 10.1073/pnas.84.3.675

PubMed ID

  • 3543933

Additional Document Info

start page

  • 675

end page

  • 9


  • 84


  • 3