Kjærulff, Louise3; Nielsen, Anita6; Månsson, Maria3; Gram, Lone7; Larsen, Thomas Ostenfeld8; Ingmer, Hanne6; Gotfredsen, Charlotte Held1
1 Department of Chemistry, Technical University of Denmark2 Organic Chemistry, Department of Chemistry, Technical University of Denmark3 Department of Systems Biology, Technical University of Denmark4 Natural Product Chemistry, Department of Systems Biology, Technical University of Denmark5 Bacterial Ecophysiology and Biotechnology, Department of Systems Biology, Technical University of Denmark6 University of Copenhagen7 Bacterial Ecophysiology and Biotechnology, Department of Biotechnology and Biomedicine, Technical University of Denmark8 Natural Product Discovery, Department of Biotechnology and Biomedicine, Technical University of Denmark
During our search for new natural products from the marine environment, we discovered a wide range of cyclic peptides from a marine Photobacterium, closely related to P. halotolerans. The chemical fingerprint of the bacterium showed primarily non-ribosomal peptide synthetase (NRPS)-like compounds, including the known pyrrothine antibiotic holomycin and a wide range of peptides, from diketopiperazines to cyclodepsipeptides of 500–900 Da. Purification of components from the pellet fraction led to the isolation and structure elucidation of four new cyclodepsipeptides, ngercheumicin F, G, H, and I. The ngercheumicins interfered with expression of virulence genes known to be controlled by the agr quorum sensing system of Staphylococcus aureus, although to a lesser extent than the previously described solonamides from the same strain of Photobacterium.
Marine Drugs, 2013, Vol 11, Issue 12, p. 5051-5062
Photobacterium; Depsipeptide; Structure elucidation; Quorum sensing; Antivirulence; agr