The solution structure of the leader sequence of the patellamide precursor peptide was analysed by using CD and determined with NOE-restrained molecular dynamics calculations. This leader sequence is highly conserved in the precursor peptides of some other cyanobactins harbouring heterocycles, and is assumed to play a role in targeting the precursor peptide to the post-translational machinery. The sequence was observed to form an a-helix spanning residues 13-28 with a hydrophobic surface on one side of the helix. This hydrophobic surface is proposed to be the site of the initial binding with modifying enzymes.
- protein secondary structure
- 2-dimensional NMR-spectroscopy
- carboxylation recognition site
- microcin B17
- mutational analysis