title: Identification of four new agr quorum sensing-interfering cyclodepsipeptides from a marine Photobacterium.
abstract: 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.
authors.forename: Louise
authors.initials: L
authors.lastname: Kjaerulff
authors.forename: Anita
authors.initials: A
authors.lastname: Nielsen
authors.forename: Maria
authors.initials: M
authors.lastname: Mansson
authors.forename: Lone
authors.initials: L
authors.lastname: Gram
authors.forename: Thomas O
authors.initials: TO
authors.lastname: Larsen
authors.affiliation: Department of Chemistry, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark. anini@sund.ku.dk.
authors.forename: Hanne
authors.initials: H
authors.lastname: Ingmer
authors.affiliation: Department of Chemistry, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark. chg@kemi.dtu.dk.
authors.forename: Charlotte H
authors.initials: CH
authors.lastname: Gotfredsen
mesh_terms: D000900:Anti-Bacterial Agents / Q000302:isolation & purification / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D047630:Depsipeptides / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D007769:Lactams / Q000378:metabolism; D010453:Peptide Synthases / Q000235:genetics / Q000378:metabolism; D010776:Photobacterium / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D053038:Quorum Sensing / Q000187:drug effects* / Q000235:genetics; D013211:Staphylococcus aureus / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D014774:Virulence / Q000235:genetics
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D047630:Depsipeptides; D007769:Lactams; C015265:holomycin; D010453:Peptide Synthases; C104385:non-ribosomal peptide synthase