Article

Site-specific chemical modification of recombinant proteins produced in mammalian cells by using the genetically encoded aldehyde tag

Department of Chemistry, University of California, Berkeley, CA 94720-1460, USA.
Proceedings of the National Academy of Sciences (Impact Factor: 9.81). 03/2009; 106(9):3000-5. DOI: 10.1073/pnas.0807820106
Source: PubMed

ABSTRACT The properties of therapeutic proteins can be enhanced by chemical modification. Methods for site-specific protein conjugation are critical to such efforts. Here, we demonstrate that recombinant proteins expressed in mammalian cells can be site-specifically modified by using a genetically encoded aldehyde tag. We introduced the peptide sequence recognized by the endoplasmic reticulum (ER)-resident formylglycine generating enzyme (FGE), which can be as short as 6 residues, into heterologous proteins expressed in mammalian cells. Cotranslational modification of the proteins by FGE produced products bearing a unique aldehyde group. Proteins bearing this "aldehyde tag" were chemically modified by selective reaction with hydrazide- or aminooxy-functionalized reagents. We applied the technique to site-specific modification of monoclonal antibodies, the fastest growing class of biopharmaceuticals, as well as membrane-associated and cytosolic proteins expressed in mammalian cells.

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Available from: Wenqing Shui, Jun 13, 2015
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