Estimating the energetic contribution of hydrogen bonding to the stability of Candida methylica formate dehydrogenase by using double mutant cycle


Karaguler N. , SESSIONS R., MORETON K., CLARKE A., HOLBROOK J.

BIOTECHNOLOGY LETTERS, vol.26, no.14, pp.1137-1140, 2004 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 26 Issue: 14
  • Publication Date: 2004
  • Doi Number: 10.1023/b:bile.0000035485.43826.03
  • Title of Journal : BIOTECHNOLOGY LETTERS
  • Page Numbers: pp.1137-1140

Abstract

An homology model of Candidamethylica formate dehydrogenase (cmFDH) was constructed based on the Pseudomonas sp. 101 formate dehydrogenase (psFDH) structure. In wild type cmFDH, Thr169 and Thr226 can form hydrogen bonds with each other. We measured the interaction energy between the two threonines independent of other interactions in the proteins by using a so-called double mutant cycle and assessing the protein stability from the concentration of guanidine hydrochloride needed to denature 50% of the molecules. We conclude that the hydrogen bonds stabilize the wild type protein by -4 kcal mol(-1).