Mycosporine-glutamicol-glucoside: a natural UV-absorbing secondary metabolite of rock-inhabiting microcolonial fungi.

Institute of Chemistry and Biology of the Marine Environment (ICBM), Carl von Ossietzky University Oldenburg, PO Box 2503, 26111 Oldenburg, Germany.
Rapid Communications in Mass Spectrometry (Impact Factor: 2.64). 02/2003; 17(9):897-902. DOI: 10.1002/rcm.997
Source: PubMed

ABSTRACT Microcolonial ascomycetes are known to inhabit bare rock surfaces in cold and hot deserts and thus are habitually exposed to high levels of solar radiation. Several of these stress-tolerant fungal isolates, cultivated in the laboratory under daylight illumination, were studied for the presence of effective UV-radiation protection substances. Liquid chromatography/mass spectrometry (LC/MS) and liquid chromatography/tandem mass spectrometry (LC/MS/MS) analyses allowed for efficient separation and structure clarification of two mycosporines. It was demonstrated that both mycosporine-glutamicol-glucoside and mycosporine-glutaminol-glucoside are natural and constitutive secondary metabolites of microcolonial fungi. The function and relation of these substances in the fungal cell are discussed.

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