A glycosylated tetramic acid, virgineone (1), was isolated from saprotrophic Lachnum virgineum. The antifungal activity of the fermentation extract of L. virgineum was characterized in the Candida albicans fitness test as distinguishable from other natural products tested. Bioassay-guided fractionation yielded 1, a tyrosine-derived tetramic acid with a C-22 oxygenated chain and a β-mannose. It displayed broad-spectrum antifungal activity against Candida spp. and Aspergillus fumigatus with a MIC of 4 and 16 μg/mL, respectively. Virgineone was also identified in a number of Lachnum strains collected from diverse geographies and habitats.
Candida albicans, antifungal activity, caspofungin, tetramic acid derivative, virgineone, Lachnum virgineum
NCBI PubMed ID: 19115836Publication DOI: 10.1021/np800511rJournal NLM ID: 7906882Publisher: American Society of Pharmacognosy
Correspondence: sheo_singh@merck.com
Institutions: Natural Products Chemistry, Merck Research Laboratories, Rahway, USA, Centro de Investigación Básica, Merck Sharp and Dohme de España, Madrid, Spain, Infectious Diseases, Merck Research Laboratories, Rahway, USA, Center of Fungal Genetics, Merck Frosst Canada Ltd., Montreal, Canada
Methods: 13C NMR, 1H NMR, IR, DNA sequencing, acid hydrolysis, biological assays, HPLC, UV, extraction, HR-ESI-MS, DEPT, COSY, antifungal activity test
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