A Strategy for Creating Organisms Dependent on Noncanonical Amino Acids. (27th June 2017)

• Record Type: Journal Article
• Authors: Xuan, Weimin; Schultz, Peter G.
• Is Part Of: Angewandte Chemie. Volume 129:Number 31(2017)
• Page Start: 9298
• Page End: 9301
• Publication Date: 2017-06-27
• Subjects: Desacetylierung -- Lebendimpfstoffe -- Lysin -- Nichtkanonische Aminosäuren -- Posttranslationale Modifikationen; Chemistry -- Periodicals; 540
• DOI: 10.1002/ange.201703553
• Languages: English
• ISSNs: 0044-8249

Abstract

Abstract: The use of noncanonical amino acids (ncAAs) to control the viability of an organism provides a strategy for the development of conditional "kill switches" for live vaccines or engineered human cells. We report an approach inspired by the posttranslational acetylation/deacetylation of lysine residues, in which a protein encoded by a gene with an in‐frame nonsense codon at an essential lysine can be expressed in its native state only upon genetic incorporation of N ‐ ϵ ‐acetyl‐l ‐Lys (AcK), and subsequent enzymatic deacetylation in the host cell. We applied this strategy to two essential E. coli enzymes: the branched‐chain aminotransferase BCAT and the DNA replication initiator protein DnaA. We also devised a barnase‐based conditional suicide switch to further lower the escape frequency of the host cells. This strategy offers a number of attractive features for controlling host viability, including a single small‐molecule‐based kill switch, low escape frequency, and unaffected protein function.