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4-ketoproline: An electrophilic proline analog for bioconjugation.

ABSTRACT: Installing an electrophilic amino-acid residue can engender a peptide or protein with chemoselective reactivity. Such a modification to collagen, which is the most abundant protein in animals, could facilitate the development of new biomaterials. Collagen has an abundance of proline-like residues. Here, we report on the incorporation of an electrophilic proline congener, (2S)-4-ketoproline (Kep), into a collagen-mimetic peptide (CMP). An ab initio conformational analysis of Kep revealed its potential to be accommodated within a collagen triple helix. A synthetic CMP containing a Kep residue was indeed able to form a stable triple helix. Moreover, the condensation of its carbonyl group with aminooxy-biotin did not compromise the conformational stability of the triple helix. These data encourage the use of 4-ketoproline as an electrophilic congener of proline.

SUBMITTER: Choudhary A

PROVIDER: S-EPMC4376587 | biostudies-literature | 2015 Mar

REPOSITORIES: biostudies-literature

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4-ketoproline: An electrophilic proline analog for bioconjugation.

Choudhary Amit A Kamer Kimberli J KJ Shoulders Matthew D MD Raines Ronald T RT

Biopolymers 20150301 2

Installing an electrophilic amino-acid residue can engender a peptide or protein with chemoselective reactivity. Such a modification to collagen, which is the most abundant protein in animals, could facilitate the development of new biomaterials. Collagen has an abundance of proline-like residues. Here, we report on the incorporation of an electrophilic proline congener, (2S)-4-ketoproline (Kep), into a collagen-mimetic peptide (CMP). An ab initio conformational analysis of Kep revealed its pote ...[more]

PMID: 25656588

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