Systematic Activity Maturation of a Single-Domain Antibody with Non-canonical Amino Acids through Chemical Mutagenesis. Issue 1 (21st January 2021)

• Record Type: Journal Article
• Authors: Lindstedt, Philip R.; Aprile, Francesco A.; Sormanni, Pietro; Rakoto, Robertinah; Dobson, Christopher M.; Bernardes, Gonçalo J.L.; Vendruscolo, Michele
• Is Part Of: Cell chemical biology. Volume 28:Issue 1(2021)
• Page Start: 70
• Page End: 77.e5
• Publication Date: 2021-01-21
• Subjects: antibody maturation -- chemical mutagenesis -- non-natural amino acids -- protein aggregation; Biochemistry -- Periodicals; 572.05
• DOI: 10.1016/j.chembiol.2020.11.002
• Languages: English
• ISSNs: 2451-9456

Abstract

Summary: Great advances have been made over the last four decades in therapeutic and diagnostic applications of antibodies. The activity maturation of antibody candidates, however, remains a significant challenge. To address this problem, we present a method that enables the systematic enhancement of the activity of a single-domain antibody through the post-translational installation of non-canonical side chains by chemical mutagenesis. We illustrate this approach by performing a structure-activity relationship study beyond the 20 naturally occurring amino acids on a single-domain antibody designed in silico to inhibit the aggregation of the amyloid-β peptide, a process closely linked to Alzheimer's disease. We found that this approach can improve, by five orders of magnitude, the anti-aggregation activity of the starting single-domain antibody, without affecting its stability. These results show that the expansion of the chemical space available to antibodies through chemical mutagenesis can be exploited for the systematic enhancement of the activity of these molecules. Graphical Abstract: Highlights: Chemical mutagenesis was pursued along the CDR3 loop of a single-domain antibody Sites deemed accessible had diverse side chains screened for activity enhancement Final mutant had greatly enhanced activity and maintained other desired properties Abstract : Lindstedt et al. investigated the application of chemical mutagenesis to perform a SAR study on a single-domain antibody. The final chemical mutant had greatly enhanced activity with only one side-chain alteration and maintained other biophysical properties, highlighting the utility of this minimalist approach for protein activity maturation.