Caged Tyrosine Residues

Following the style of presentation used in Imperiali s paper concerning the synthesis of caged phosphopeptides the general route for synthesis of peptides containing 2-nitrophenylethyl-caged phosphoserine-threonine and tyrosine residue is presented below. 

Scheme 3.2-11 Tyrosine residues equipped with various caging groups rendered peptides inactive with respect to SH2-domain binding.

Transferrin and lactoferrin belong to a family of Fe cation buffer and carrier proteins. X-ray crystallography has shown that both proteins include two distorted octahedral Fe + sites, each of which is coordinated with one aspartate, one histidine, and two tyrosinate residues as well as one exogenous carbonate. Luminescent lanthanides such as Tb + and Eu + cations can be incorporated along with Ee cations into these binding sites to provide water-soluble luminescent lanthanide complexes in sophisticated three-dimensional cages. 

Figure 5 Photolysis of 2-nitrobenzyl caged serine (a) and tyrosine (b) restores the wild-type residues. Photolysis of 2-nitrophenyl glycine (c) cleaves the protein backbone.

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