Planta Med 2006; 72 - P_139
DOI: 10.1055/s-2006-949939

New cyclic peptides from the cyanobacterium Tychonema sp

C Mehner 1, S Kehraus 1, A Krick 1, D Müller 1, GM König 1
  • 1Institute for Pharmaceutical Biology, University of Bonn, Nußallee 6, D-53115 Bonn, Germany, mehchr2@web.de

Cyanobacteria are an amazing source of new compounds of pharmaceutical interest. A specific feature of their secondary metabolite spectrum is the occurrence of cyclic peptides containing unusual amino acids. Our project focuses on a group of bioactive cyclic peptides, which are present in the methanolic extract of the cyanobacterium Tychonema sp. This microorganism was isolated from a field sample collected from a pond of a sugar factory near Braunschweig (Germany). To date the new cyclic hexapeptides brunsvicamides A-C were identified. Brunsvicamide C contains a unique N-methylated-N'-formyl-kynurenine moiety 1 [1]. The brunsvicamides are related to the sponge-derived mozamides.

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Furthermore two cyclic peptides with [MH+]=1486 and [MH+]=1456 were isolated. The structure elucidation of these peptides is still ongoing using a combination of NMR methods and MS/MS spectroscopy.

Reference: 1. König, G.M., Kehraus, S. et al. (2006), ChemBioChem 7: 229–238.