Biosynthetic Incorporation of Fluorohistidine into Proteins in E. coli: A New Probe of Macromolecular Structure

Fluorine, the other hydrogen: Fluorinated forms of histidine, namely 2- and 4-fluorohistidines (see scheme), have dramatically reduced side-chain pKa's compared to the native amino acid. Biosynthetic incorporation of these analogues into bacterially expressed proteins should, therefore, broaden studies that are aimed at understanding pH- dependent processes. In this study we apply this technique to the production of fluorinated PapD chaperone.