NMR Analysis of Unnatural Amino Acids in Natural Antibiotics

  • Franca CastiglioneEmail author
Part of the Methods in Molecular Biology book series (MIMB, volume 794)


A large number of modified amino acids other than the canonical amino acid residues can be found in natural products, especially antibiotics. The structure of these peptide-based compounds is investigated using modern two-dimensional NMR techniques. The automatic assignment of the 2D NMR proton spectra and consequent determination of the primary and 3D structure of peptides or small size proteins containing natural amino acids is nowadays routine. However, a deficiency in the ability to readily sequence peptides containing unnatural amino acids still remains and a great human effort and time is required. The experimental methods and the protocols of manual analysis of the data are described in the following sections.

Key words

Unnatural amino acids NMR spectroscopy Structure Antibiotics 


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Copyright information

© Springer Science+Business Media, LLC 2012

Authors and Affiliations

  1. 1.Dipartimento di Chimica, Materiali e Ingegneria Chimica “G. Natta”Politecnico di MilanoMilanoItaly

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