Towards Targeted Protein Degradation in Escherichia coli - depletion of the essential GroEL protein using CLIPPERs.

New, universal tools for targeted protein degradation in bacteria can help to accelerate protein function studies and antimicrobial research. We have created a new method for degrading bacterial proteins using plasmid-encoded degrader peptides which deliver target proteins for degradation by a highly conserved ClpXP protease. We demonstrated the mode-of-action of the degraders on a challenging essential target GroEL. The studies in bacteria were complemented by in vitro binding and structural studies. Expression of degrader peptides resulted in a temperature-dependent growth inhibition and depletion of GroEL levels over time. The reduction of GroEL levels was accompanied by dramatic proteome alterations. The presented method offers a new alternative approach for regulating protein levels in bacteria without genomic modifications or tag fusions. Our studies demonstrate that ClpXP is an attractive protease for the future use in bacterial targeted protein degradation.