We have found a novel phospholipid antibiotic (named bacilysocin) which accumulates within (or associates with) the cells of Bacillus subtilis 168 and determined the structure by nuclear magnetic resonance and mass spectrometry analyses. The structure of bacilysocin elucidated was 1-(12-methyltetradecanoyl)-3-phosphoglyceroglycerol. Bacilysocin demonstrated antimicrobial activity, especially against certain fungi. Production of bacilysocin commenced immediately after growth ceased and before the formation of heat-resistant spores. The production of bacilysocin was completely blocked when the ytpA gene, which encodes a protein homologous to lysophospholipase, was disrupted, but blockage of the ytpA gene did not significantly affect growth. Sporulation was also impaired, with a 10-fold reduction in heat-resistant spore titers being detected. Since the ytpA disruptant actually lacked phospholipase activity, we propose that the YtpA protein functions as an enzyme for the biosynthesis of bacilysocin.
Biosynthetic pathways of ebelactone A and B were studied by 13C NMR spectroscopy. By using 13C labeled compounds as precursors it was determined that ebelactone A was derived from one molecule of acetic acid and six propionic acids and ebelactone B from one molecule of acetic acid, five propionic acids and one butyric acid.
Title: Structural studies on ebelactone A and B, esterase inhibitors produced by actinomycetes Uotani K, Naganawa H, Kondo S, Aoyagi T, Umezawa H Ref: J Antibiot (Tokyo), 35:1495, 1982 : PubMed
