An Update on Organohalogen Metabolites Produced by Basidiomycetes

Abstract

Basidiomycetes are an ecologically important group of higher fungi known for their widespread capacity to produce organohalogen metabolites. To date, 100 different organohalogen metabolites (mostly chlorinated) have been identified from strains in 70 genera of Basidiomycetes. This manuscript provides an update of newly discovered chlorinated metabolites described since 1997.Additionally, the biosynthesis, physiological role, environmental fate and significance of Basidiomycete organohalogen metabolites are reviewed. Novel metabolites include chlorinated methoxybenzene azoxyformamide, pterulones (chlorinated 1-benzoxepins), chlorinated anisylpropanoids, tri-and tetrachlorinated phenols. Chlorinated p-anisyl metabolites (CAM) are the most ubiquitous and ecologically significant natural organohalogens produced by higher fungi. Evidence is presented indicating their synthesis from phenylalanine via the phenylpropanoid pathway. They are estimated to be produced at a rate of 300 g ha -1 year -1 in European forests inhabited by the common occurring mushroom, Hypholoma fasciculare. Organohalogen metabolites have several purposeful physiological functions ranging from antibiotic properties, metabolites involved in lignin degradation and synthons for biosynthesis.

Spatial variation in natural formation of chloroform in the soils of four coniferous forests

“…This was expected since the presumed modes of formation are very different, with methyl halides being formed either by direct bio-synthesis in fungi (Harper et al 1988;Field et al 1997) or by abiotic nucleophilic substitution of methoxy groups in pectin or lignin (Hamilton et al 2003;Keppler et al 2005).…”

Further Biochemical Profiling of Hypholoma fasciculare Metabolome Reveals Its Chemogenetic Diversity

“…3-Phosphoshikimate-1-carboxyvinyltransferase is a multidomain enzyme with a main role in catalyzing the conversion of phenylalanine-like compounds to cinnamic acid derivatives. Subsequent hydroxylation and reduction on the resulting acids lead to the production of anisaldehyde isomers such as 3,5-D (Field et al, 1996). The biological activity of chlorinated natural products is well documented (Hautzel and Anke, 1990; 14)diene, humulene, naphthalene, gleenol, cubenene, bicylosesquiphellandrene, Cubenol, and alpha-copaene] were characterized using HP-5 MS quartz capillary column (30 m × 0.25 mm, 0.25-µm film thickness).…”