Taxonomic identity of the Sterile Red Fungus inferred using nuclear rDNA ITS 1 sequences

The taxonomic position and properties of an unidentified fungus isolated from wheat roots was investigated. The Sterile Red Fungus (SRF) is characterised by its fast growing habit, red pigmentation, non-sporing nature and mycelial form resembling some Laetisaria and Limonomyces species. rDNA variation was used to study the relationship of the SRF to Laetisaria spp. and Limonomyces spp. Nucleotide sequence obtained from eight Laetisaria and three Limonomyces species representing the ITS 1 region, were analysed by PCR and direct sequencing. Plant growth promoting properties of the five taxa were also determined. The SRF had closest identity (98%) to British material of Limonomyces roseipellis. UPGMA analysis of ITS 1 DNA sequence support a close relationship between SRF and L. roseipellis. The relationship inferred by nucleotide sequence data was supported by phenotypic analysis; both L. roseipellis and the SRF were shown to promote the growth of wheat plants. Unexpectedly, Laetisaria arvalis and material named as Limonomyces roseipellis from New Zealand appeared to be closely related with 98% rDNA sequence identity, suggesting the misidentification of the New Zealand collection

An unusual oxalylated tetramic acid from the New Zealand basidiomycete Chamonixia pachydermis

An unusual oxalylated tetramic acid, pachydermin (1), has been isolated from the New Zealand basidiomycete Chamonixia pachydermis. The full structure, which was not directly accessible by NMR methods, was deduced from that of a degradation product, 5-(3-chloro-4-hydroxybenzylidene)tetramic acid (2). The degradation product 2 exhibited mild antibacterial activity against Bacillus subtilis

Excelsione, a depsidone from an endophytic fungus isolated from the New Zealand endemic tree, Knightia excelsa

A new tetracyclic depsidone, excelsione (1), was isolated from the extract of an unidentified fungal endophyte obtained from the New Zealand endemic tree Knightia excelsa. The structure was elucidated by X-ray crystallography and NMR spectroscopy

Chrysosporide, a Cyclic Pentapeptide from a New Zealand Sample of the Fungus Sepedonium chrysospermum

A new cyclic pentapeptide, chrysosporide (1), was isolated from a New Zealand sample of the mycoparasitic fungus Sepedonium chrysospermum by bioactivity-guided fractionation. The planar structure was deduced by detailed spectroscopic analysis, and the absolute configurations of the amino acid residues were defined by Marfey's method. As both enantiomers of Leu occurred in chrysosporide, molecular mechanics calculations were applied to the analysis to distinguish between the possible structural isomers. Only the lowest energy conformers of the cyclo-(l-Val-d-Ala-l-Leu-l-Leu-d-Leu) isomer were in agreement with the observed NOEs, suggesting that this was the most probable amino acid sequence for chrysosporide (1)

Bioactivity profiling using HPLC/microtitre-plate analysis: application to a New Zealand marine alga-derived fungus, Gliocladium sp.

Using HPLC/microtiter-plate-based generation of activity profiles the extract of a marine alga-derived fungus, identified as Gliocladium sp., was shown to contain the known strongly cytotoxic metabolite 4-keto-clonostachydiol (1) and also clonostachydiol (2) as well as gliotide (3), a new cyclodepsipeptide containing several d-amino acids. The absolute configuration of 1 was elucidated by reduction to 2, and two further oxidized derivatives of clonostachydiol (5, 6) were prepared and evaluated for biological activity