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Enhancing the incorporation of lysine derivatives into proteins with methylester forms of unnatural amino acids.

ABSTRACT: We have improved the incorporation of l- and d-forms of unnatural amino acid (UAA) N?-thiaprolyl-l-lysine (ThzK) into ubiquitin (UB) and green fluorescent protein (GFP) by 2-6 folds with the use of the methylester forms of the UAAs in E coli cell culture. We also improved the yields of UAA-incorporated UB and GFP with the methylester forms of N?-Boc-l-Lysine (BocK) and N?-propargyl-l-Lysine (PrK) by 2-5 folds compared to their free acid forms. Our work demonstrated that using methylester-capped UAAs for protein expression is a useful strategy to enhance the yields of UAA-incorporated proteins.

SUBMITTER: Zhou H

PROVIDER: S-EPMC7644286 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature

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Enhancing the incorporation of lysine derivatives into proteins with methylester forms of unnatural amino acids.

Zhou Han H Cheung Jenny W JW Carpenter Tomaya T Jones Stacey K SK Luong Nhu H NH Tran Nhi C NC Jacobs Savannah E SE Galbada Liyanage Sahan A SA Cropp T Ashton TA Yin Jun J

Bioorganic & medicinal chemistry letters 20191204 2

We have improved the incorporation of l- and d-forms of unnatural amino acid (UAA) Nε-thiaprolyl-l-lysine (ThzK) into ubiquitin (UB) and green fluorescent protein (GFP) by 2-6 folds with the use of the methylester forms of the UAAs in E coli cell culture. We also improved the yields of UAA-incorporated UB and GFP with the methylester forms of Nε-Boc-l-Lysine (BocK) and Nε-propargyl-l-Lysine (PrK) by 2-5 folds compared to their free acid forms. Our work demonstrat ...[more]

PMID: 31836447

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