Semisynthesis, protein

Several Applications of EPL and Intein Splicing for Protein Semisynthesis and Engineering... 

Split-Inteins for Protein Semisynthesis in vitro and in vivo... 

The term protein semisynthesis broadly refers to the covalent linking of a recombinant protein fragment with a synthetic moiety. A wide array of approaches have been used here, perhaps the most common being the chemical modification of a cysteine residue introduced by site-directed mutagenesis. 

Protein semisynthesis and, in particular, EPL can provide a straightforward route to phosphonate incorporation. Indeed, these techniques prove valuable for site-specific incorporation of the standard phosphoamino acids which have been effectively used in structural and enzymatic analyses [9, 23]. EPL is most efficiently used when the phosphate modification is within 50 amino acids of... 

Fig. 10.1-12 Principle of protein semisynthesis in living cells. The protein transduction domain (PTD) delivers the probe to the cell, which is followed by complementation of the DnaE intein halves and protein splicing.

Proteases - Proteases have been applied to several synthetic purposes the most Important of which are peptide bond synthesis and protein semisynthesis. Recent extensive reviews cover this area. Prote-ases have been used in ester synthesis and resolution. Semisynthesis of human insulin has been achieved by enzymic removal and replacement of one amino acid in porcine insulin. All peptide bonds in the N-termlnal octapeptide of dynorphln [H-Tyr-Gly-Gly-Phe-Leu-Arg-Arg-Ile-OH] have been formed using proteases.A precursor of aspartame has been made by themolysin-catalyzed condensation of benzyloxycarbonyl-L-aspartic acid and L-phenylalanlne methyl ester. 

Goody R S, Durek T, Waldmann H, et al. (2005). Application of protein semisynthesis for the construction of functionalized posttranslationally modified rab GTPases. Methods Enzymol. 403 29-42. 

In Geneva, at the Centre Medicale Universitaire, R.E. Offord continues his pioneering work, started in Oxford, on protein semisynthesis, but extended his studies to the spontaneous coupling of segments as well. 

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