Continuous directed evolution of proteins with improved soluble expression.

Nat Chem Biol
Authors
Keywords
Abstract

We report the development of soluble expression phage-assisted continuous evolution (SE-PACE), a system for rapidly evolving proteins with increased soluble expression. Through use of a PACE-compatible AND gate that uses a split-intein pIII, SE-PACE enables two simultaneous positive selections to evolve proteins with improved expression while maintaining their desired activities. In as little as three days, SE-PACE evolved several antibody fragments with >5-fold improvement in expression yield while retaining binding activity. We also developed an activity-independent form of SE-PACE to correct folding-defective variants of maltose-binding protein (MBP) and to evolve variants of the eukaryotic cytidine deaminase APOBEC1 with improved expression properties. These evolved APOBEC1 variants were found to improve the expression and apparent activity of Cas9-derived base editors when used in place of the wild-type cytidine deaminase. Together, these results suggest that SE-PACE can be applied to a wide variety of proteins to rapidly improve their soluble expression.

Year of Publication
2018
Journal
Nat Chem Biol
Volume
14
Issue
10
Pages
972-980
Date Published
2018 10
ISSN
1552-4469
DOI
10.1038/s41589-018-0121-5
PubMed ID
30127387
PubMed Central ID
PMC6143403
Links
Grant list
F32 GM119228 / GM / NIGMS NIH HHS / United States
RM1 HG009490 / HG / NHGRI NIH HHS / United States
R35 GM118062 / GM / NIGMS NIH HHS / United States
R01 EB022376 / EB / NIBIB NIH HHS / United States
HHMI / Howard Hughes Medical Institute / United States