Synergistic stabilization of a double mutant in chymotrypsin inhibitor 2 from a library screen in E. coli.

ABSTRACT: Most single point mutations destabilize folded proteins. Mutations that stabilize a protein typically only have a small effect and multiple mutations are often needed to substantially increase the stability. Multiple point mutations may act synergistically on the stability, and it is often not straightforward to predict their combined effect from the individual contributions. Here, we have applied an efficient in-cell assay in E. coli to select variants of the barley chymotrypsin inhibitor 2 with increased stability. We find two variants that are more than 3.8 kJ mol^-1 more stable than the wild-type. In one case, the increased stability is the effect of the single substitution D55G. The other case is a double mutant, L49I/I57V, which is 5.1 kJ mol^-1 more stable than t

SUBMITTER: Hamborg L 

PROVIDER: S-EPMC8373930 | biostudies-literature | 2021 Aug

REPOSITORIES: biostudies-literature