Delitschia confertaspora (ATCC 74209). A. Ascomata on V8 juice agar. B. 64-spored ascus. C. Ascospore.

Delitschia confertaspora was described from an isolate from dung of a rock hyrax (Procavia capensis) collected in Namibia (1). It was recognized as a new species based on the fact that post-meiotic cell divisions in the asci resulted in 64-spored asci, and the ascospores differed from the other two known 64-spored Delitschia species in their spore dimensions and configuration of the germ slit and gelatinous sheath. A culture extracts was active in an assay for influenza transcription inhibitors. The active component was found to be a 2,6-diketopiperazine derivative, named flutimide, which inhibited a cap-dependent endonuclease of influenza viral RNA polymerase, an enzyme essential for transcription of influenza virus and its replication in cell culture (2). The biosynthetic pathway leading to flutimide in culture remains unknown. It likely arises from modification of a cyclic dipeptide linked in a distinctive way, and resulting from a 2-module non-ribosomal peptide synthase. Because flutimide is constructed in an unusual way relative to other epidithiodioxopiperazines and dipeptide-derived metabolites, the genetic machinery encoding the enzymatic reactions for its biosynthesis may be novel.
Delitischia species appear late in the coprophilous fungal succession, and therefore are likely to contribute to the deconstruction of more complex plant polymers. The late successional success of Delitschia species also implies that they likely defend their microhabitat from niche-overlapping organisms through chemical interference (3, 4). Late successional coprophilous fungi have demonstrated an exceptional potential for antibiotic discovery, as evidenced by a high frequency of novel antibiotics, especially antifungals, from limited efforts to screen coprophilous strains (5).

1.    F Peláez, JD Polishook, M Valldosera, J Guarro. Mycotaxon 50, 115 (1994).
2.    JE Tomassini et al. Antimicrob. Agents Chemother. 40, 1189 (1996).
3.    DT Wicklow, in The Fungal Community. Its Organization and Role in the Ecosystem. 2nd Ed., G. C. Carroll, D. T. Wicklow, Eds. (Marcel Dekker, Inc., New York, 1992),  pp. 715-728.
4.    JB Gloer, in Environmental and Microbial Relationships, 2nd Ed. The Mycota IV, C. P. Kubicek, I. S. Druzhinina, Eds. (Springer-Verlag, Berlin Heidelberg, 2007),  pp. 257-283.
5.    GF Bills, JB Gloer, Z An. Curr. Opin. Microbiol. 16, 549 (2013).