A designed protein for the specific and covalent heteroconjugation of biomolecules

Ecole Polytechnique Fédérale de Lausanne (EPFL), Institute of Chemical Sciences and Engineering, CH-1015 Lausanne, Switzerland.
Bioconjugate Chemistry (Impact Factor: 4.82). 09/2008; 19(9):1753-6. DOI: 10.1021/bc800268j
Source: PubMed

ABSTRACT Bioconjugations often rely on adaptor molecules to cross-link different biomolecules. In this work, we introduce the molecular adaptor covalin, which is a protein chimera of two self-labeling proteins with nonoverlapping substrate specificity. Covalin permits a selective and covalent heteroconjugation of biomolecules displaying appropriate functional groups. Examples for the use of covalin include the specific heteroconjugation of a reporter enzyme to an antibody and of molecular probes to the surface of living cells. The efficiency and specificity of covalin-based bioconjugations together with the availability of a large variety of substrates create immediate and ubiquitous applications for covalin in bioconjugate chemistry.

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