Send to

Choose Destination
See comment in PubMed Commons below
Antioxid Redox Signal. 2011 Mar 15;14(6):973-84. doi: 10.1089/ars.2010.3712. Epub 2011 Jan 23.

Genetic selection for enhanced folding in vivo targets the Cys14-Cys38 disulfide bond in bovine pancreatic trypsin inhibitor.

Author information

  • 1Department of Molecular, Cellular and Developmental Biology, Howard Hughes Medical Institute, University of Michigan, Ann Arbor, Michigan 48109, USA.


The periplasm provides a strongly oxidizing environment; however, periplasmic expression of proteins with disulfide bonds is often inefficient. Here, we used two different tripartite fusion systems to perform in vivo selections for mutants of the model protein bovine pancreatic trypsin inhibitor (BPTI) with the aim of enhancing its expression in Escherichia coli. This trypsin inhibitor contains three disulfides that contribute to its extreme stability and protease resistance. The mutants we isolated for increased expression appear to act by eliminating or destabilizing the Cys14-Cys38 disulfide in BPTI. In doing so, they are expected to reduce or eliminate kinetic traps that exist within the well characterized in vitro folding pathway of BPTI. These results suggest that elimination or destabilization of a disulfide bond whose formation is problematic in vitro can enhance in vivo protein folding. The use of these in vivo selections may prove a valuable way to identify and eliminate disulfides and other rate-limiting steps in the folding of proteins, including those proteins whose in vitro folding pathways are unknown.

[PubMed - indexed for MEDLINE]
Free PMC Article
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Mary Ann Liebert, Inc. Icon for PubMed Central
    Loading ...
    Support Center