The crystal structure of the naturally split gp41-1 intein guides the engineering of orthogonal split inteins from cis-splicing inteins

FEBS J. 2020 May;287(9):1886-1898. doi: 10.1111/febs.15113. Epub 2019 Nov 19.

Abstract

Protein trans-splicing catalyzed by split inteins has increasingly become useful as a protein engineering tool. We solved the 1.0 Å-resolution crystal structure of a fused variant from the naturally split gp41-1 intein, previously identified from environmental metagenomic sequence data. The structure of the 125-residue gp41-1 intein revealed a compact pseudo-C2-symmetry commonly found in the Hedgehog/Intein superfamily with extensive charge-charge interactions between the split N- and C-terminal intein fragments that are common among naturally occurring split inteins. We successfully created orthogonal split inteins by engineering a similar charge network into the same region of a cis-splicing intein. This strategy could be applicable for creating novel natural-like split inteins from other, more prevalent cis-splicing inteins. DATABASE: Structural data are available in the RCSB Protein Data Bank under the accession number 6QAZ.

Keywords: crystal structure; gp41-1 intein; orthogonal split intein; protein engineering; protein splicing.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, N.I.H., Intramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Crystallography, X-Ray
  • Inteins*
  • Models, Molecular
  • Protein Engineering*
  • Protein Splicing*
  • Stereoisomerism