title: Biological activity of guanacastepene, a novel diterpenoid antibiotic produced by an unidentified fungus CR115.
abstract: Fermentation extracts of culture CR115, an unknown plant endophyte originally isolated from Costa Rica, were found to be active against antibiotic-resistant bacteria. The metabolite responsible for activity was identified as a novel diterpenoid antibiotic guanacastepene (mol. wt. 374.47 and mol. formula C22H30O5). Mechanistic studies done in an E. coli imp strain suggested membrane damage as the primary mode of bactericidal action. This compound also lysed human RBCs and caused leakage of intracellular potassium from E. coli imp.
authors.affiliation: Natural Products Microbiology, Wyeth-Ayerst Research, Pearl River, NY, USA.
authors.forename: M P
authors.initials: MP
authors.lastname: Singh
authors.forename: J E
authors.initials: JE
authors.lastname: Janso
authors.forename: S W
authors.initials: SW
authors.lastname: Luckman
authors.forename: S F
authors.initials: SF
authors.lastname: Brady
authors.forename: J
authors.initials: J
authors.lastname: Clardy
authors.forename: M
authors.initials: M
authors.lastname: Greenstein
authors.forename: W M
authors.initials: WM
authors.lastname: Maiese
mesh_terms: D000900:Anti-Bacterial Agents / Q000378:metabolism / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects*; D002176:Candida albicans / Q000187:drug effects; D004224:Diterpenes / Q000378:metabolism / Q000494:pharmacology; D004912:Erythrocytes / Q000187:drug effects; D029968:Escherichia coli Proteins; D005658:Fungi / Q000254:growth & development / Q000378:metabolism*; D006461:Hemolysis; D006801:Humans; D008565:Membrane Proteins / Q000187:drug effects / Q000378:metabolism; D008826:Microbial Sensitivity Tests; D011188:Potassium / Q000378:metabolism
chemical_list: D000900:Anti-Bacterial Agents; D004224:Diterpenes; D029968:Escherichia coli Proteins; D008565:Membrane Proteins; C409194:guanacastepene; C043426:inner membrane protein, E coli; D011188:Potassium