Single-site protein labeling

Yin J, Lin AJ, Buckett PD, Wessling-Resnick M, Golan DE, Walsh CT. Single-cell ERET imaging of transferrin receptor trafficking dynamics by Sfp-catalyzed, site-specific protein labeling. Chem. Biol. 2005 12 999-1006. 

The transmembrane portion of the M2 protein from the influenza A virus has been studied in hydrated DMPC lipid bilayers with solid-state NMR.209 Orientational constraints are obtained from the isotopically labeled peptide samples mechanically aligned between thin glass plates. I5N chemical shifts from single-site labeled samples constrain the molecular frame with respect to... 

Troponin C typically lacks tryptophan residues. This is fortunate because it allows insertion of trypu han donors at any desired location by site-directed mutagenesis. In the mutant shown in Figure 14.15, a single tryptophan residue was placed at position 22 to serve as the donor. As is typical in the creation of mutant proteins, the tryptophan (W) was a conservative replacement for phenylalanine (F). A uniquely reactive site for the acceptor was provided by rqilacing asparagine-52 with a cysteine residue (N52C). This site was labeled witii lAEDANS. 

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