Abstract

Membrane proteins are targets of most available pharmaceuticals, but they are difficult to produce recombinantly, like many other aggregation-prone proteins. Spiders can produce silk proteins at huge concentrations by sequestering their aggregation-prone regions in micellar structures, where the very soluble N-terminal domain (NT) forms the shell. We hypothesize that fusion to NT could similarly solubilize non-spidroin proteins, and design a charge-reversed mutant (NT star) that is pH insensitive, stabilized and hypersoluble compared to wildtype NT. NT star-transmembrane protein fusions yield up to eight times more of soluble protein in Escherichia coli than fusions with several conventional tags. NT star enables transmembrane peptide purification to homogeneity without chromatography and manufacture of low-cost synthetic lung surfactant that works in an animal model of respiratory disease. NT star also allows efficient expression and purification of non-transmembrane proteins, which are otherwise refractory to recombinant production, and offers a new tool for reluctant proteins in general.

Published in

Nature Communications
2017, Volume: 8, article number: 15504
Publisher: NATURE PUBLISHING GROUP

SLU Authors

• Rising, Anna

  • Department of Animal Biosciences, Swedish University of Agricultural Sciences
    
  • Karolinska Institute

• Johansson, Jan

  • Department of Animal Biosciences, Swedish University of Agricultural Sciences
    
  • Karolinska Institute
  • Tallinn University

UKÄ Subject classification

Medical Bioscience


Publication identifier

DOI: https://doi.org/10.1038/ncomms15504

Permanent link to this page (URI)

https://res.slu.se/id/publ/83654