Site-specific N-terminal labeling of proteins using sortase-mediated reactions.

Whitehead Institute for Biomedical Research, Cambridge, Massachusetts, USA.
Nature Protocol (Impact Factor: 8.36). 09/2013; 8(9):1800-7. DOI: 10.1038/nprot.2013.102
Source: PubMed

ABSTRACT This protocol describes the use of sortase-mediated reactions to label the N terminus of any given protein of interest. The sortase recognition sequence, LPXTG (for Streptococcus aureus sortase A) or LPXTA (for Staphylococcus pyogenes sortase A), can be appended to a variety of probes such as fluorophores, biotin or even to other proteins. The protein to be labeled acts as a nucleophile by attacking the intermediate formed between the probe containing the LPXTG/A motif and the sortase enzyme. If sortase, the protein of interest and a suitably functionalized label are available, the reactions usually require less than 3 h.

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