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As a part of a screening programme developed to evaluate the antimicrobial activity of basidiomycetes, 317 isolates representing 204 species collected in Spain were screened against a range of human clinical pathogens and laboratory controls. Extracts from 45% of the isolates, representing 109 species, showed antimicrobial activity. Antibacterial activity was more pronounced than antifungal activity. The proportion of extracts from basidiomycetes showing antimicrobial activity was similar to or above that obtained for representative orders of Ascomycetes, such as Pezizales and Xylariales, but lower than that produced by members of the orders Diaporthales, Eurotiales, Hypocreales, Leotiales and Sordariales. Suprageneric taxa (orders and families) did not show pronounced differences in their antimicrobial activities though such differences were observed at the genus level, suggesting that the ability to produce these bioactive compounds is not homogenously distributed amongst the basidiomycetes. Isolates from some species showed large differences in their ability to produce metabolites with antimicrobial activity, possibly reflecting genetic differences at the infraspecific level.

Thirty-six strains of the fungus Epicoccum nigrum, isolated from different substrata and ecosystems of Europe, America and Africa, were analysed using 14 molecular markers included in 5 different genetic fingerprinting techniques: AP-PCR, tDNA-PCR, microsatellite-primed PCR, ARDRA and AFLP. All of the techniques used were able to differentiate the isolates, showing a high genetic diversity within the species. However, the different techniques detected different levels of similarity among the strains; ARDRA shows the most homogeneous results whilst AP-PCR shows the most heterogeneous. The similarity indices achieved for each strain were compared for the different techniques. The distribution obtained by microsatellite-primed PCR was similar to those shown by AP-PCR techniques. tDNA-PCR and AFLP rendered similar distributions, and ARDRA showed remarkably different results from the other techniques. The results also reveal the lack of an overall correlation between geographical or ecological origin of the isolates and their genotypes.

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Glarea lozoyensis is an anamorphic ascomycete that produces pneumocandin B 0 , the starting molecule for the synthesis of the antifungal drug caspofungin (CANCIDAS TM). Glarea lozoyensis was first isolated in 1985 from a water sample from Madrid, Spain. Until now, only the original strain was known, but we have discovered new strains from Argentina and the USA. Molecular phylogenetic reference to a 28S rDNA database of antibiotic-producing fungi quickly identified these strains as being conspecific with G. lozoyensis. Bayesian inference phylogeny of ITS, 28S rDNA and α-actin gene fragments revealed that G. lozoyensis is related to species of the genus Cyathicula (Helotiales). Glarea lozoyensis was not conspecific with any of the Cyathicula species sequenced, although it appears to share a common ancestor. Glarea lozoyensis and Cyathicula strains were fermented on nutritional microarrays in 96-well plates. Cyathicula extracts did not show antifungal activity and did not produce pneumocandins, whereas potent antifungal activity and pneumocandin A 0 production were confirmed for the four G. lozoyensis isolates. Also, culture morphology differed, with G. lozoyensis strains producing a dark brown, profusely sporulating mycelium with pigmented multicellular conidia accumulating in conidial masses, while all Cyathicula species tested in culture formed hyaline to light brown mycelia and lacked conidia. The chemistry and taxonomic distribution of the echinocandin class of antifungals is comprehensively reviewed.