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Knottins can be obtained either:
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Chemical Synthesis |
Since the very first solid-phase syntheses of the knottins CMTI-III and EETI-II reported in the late 80s [Kupryszewski et al, 1986; Le-Nguyen et al, 1989], great advances have been achieved in terms of strategies and methodological techniques [Boulegue et al, 2006], e.g.
Induction of disulfide connectivities with selenocysteine Use of appropriate solid support etc. Native Chemical Ligation
The solid phase synthesis works well for small peptides (~30-40 residues). To synthesize
longer peptides, the chemical ligation of pre-purified fragments is more efficient.
During the past ten years, native chemical ligation (NCL), first introduced by Dawson
et al.
[Dawson et al, 1994]
has been widely used for the synthesis of moderate-size proteins in general, and knottins
in particular
[Tam & Yu, 1997;
Daly et al, 1999;
Buczek et al, 2005;
Chino et al, 2006].
NCL consists in assembling an unprotected synthetic peptide-thioester with another unprotected
segment containing an N-terminal cysteine residue to form a native peptide bond.
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