Formation of Diketopiperazines by Penicillium italicum Isolated from Oranges

Abstract

Prolyl-2-(1′,1′-dimethylallyl)tryptophyldiketopiperazine and 12,13-dehydroprolyl-2-(1′,1′-dimethylallyl)tryptophyldiketopiperazine, known metabolites of Aspergillus ustus , were produced in low yield by Penicillium italicum in liquid culture and on unsterilized orange peel.

Metabolomics approach to understand molecular mechanisms involved in fungal pathogen–citrus pathosystems

“…81 The infected area typically displays blue or bluish-green sporulation, surrounded by a small band of unsporulated white mycelium and a broad band of soft, watersoaked peel. 65 Some studies have reported metabolites produced in the in vitro cultures of P. italicum, such as deoxybrevianamide E; [82][83][84] dehydrodeoxybrevianamide E; 83 xanthocyllin X; 84 formylxanthocillin X; 84 arabenoic acid, 84 and dehydrofulvic acid, 5-hydroxymethylfuric acid. 84 Despite these findings, the specific role of these metabolites in the interaction between P. italicum and its citrus host remains unclear.…”

Chemical Synthesis of (+)-Brevianamide a Supports a Diels–Alderase-Free Biosynthesis

“…30 Our new biosynthetic hypothesis for (+)-brevianamide A (1) involves an alternative biosynthetic precursor, (+)-dehydrodeoxybrevianamide E (9), which is a known natural product isolated from various Penicillium and Aspergillus species (Figure 2, Pathway 3). [32][33][34] Crucially, the diketopiperazine ring in (+)-dehydrodeoxybrevianamide E ( 9) is already at the oxidation level required for a later Diels-Alder reaction. Our pathway involves a point-topoint chirality transfer via a sequential diastereoselective indole oxidation, stereospecific…”