Paraphaeosphaeride D and berkleasmin F, new circumventors of arbekacin resistance in MRSA, produced by Paraphaeosphaeria sp. TR-022

Abstract

Two new compounds, designated paraphaeosphaeride D (1) and berkleasmin F (2) together with a previously known compound, berkleasmin A (3), isolated from a culture broth of the fungus Paraphaeosphaeria sp. TR-022, proved to be new circumventors of arbekacin (ABK) resistance in methicillin-resistant Staphylococcus aureus (MRSA). The structures of 1 and 2 were elucidated by spectroscopic analyses, including various NMR experiments. All compounds showed 10-100 times ABK circumvention activities using the paper disc method and reduced the MIC values of ABK against MRSA from 16 μg ml(-1) to 4 μg ml(-1) (fourfold) using the agar dilution method. These new compounds might be promising lead compounds for developing circumventors of ABK resistance in MRSA.

NF-κB inhibitors, unique γ-pyranol-γ-lactams with sulfide and sulfoxide moieties from Hawaiian plant Lycopodiella cernua derived fungus Paraphaeosphaeria neglecta FT462

“…Paraphaeosphaeria species produce different types of secondary metabolites, including macrolides 28 , 29 , xanthenes 30 , isocoumarins 31 , hexaketide 32 , polyketides 33 , 34 , and phaeosphaerides 2 and paraphaeosphaerides 1 , 2 , 8 , 35 . Paraphaeosphaeride A 2 is the first sulfur-containing molecule (a sulfide) isolated from Paraphaeosphaeria species.…”

Paraverrucsins A–F, Antifeedant, and Antiphytopathogenic Polyketides from Rhizospheric Paraphaeosphaeria verruculosa and Induced Bioactivity Enhancement by Coculturing with Host Plant Dendrobium officinale

“…Previous works led to many new metabolites from Paraphaeosphaeria sp. TR-022 . In this research, new antifungal and antifeedant metabolites from rhizospheric Paraphaeosphaeria verruculosa were identified (Figure ) .…”

“…TR-022. 7 In this research, new antifungal and antifeedant metabolites from rhizospheric Paraphaeosphaeria verruculosa were identified (Figure 1). The plant−microbe interaction can induce the productions of plant growth promoters and pharmaceuticals.…”

InBr3‐Catalyzed Coupling Reaction between Electron‐Deficient Alkenyl Ethers with Silyl Enolates for Stereoselective Synthesis of 1,5‐Dioxo‐alk‐2‐enes

“…The structure of 16 is included in berkleasmins that are eremophilane sesquiterpenoids from a saprobic fungus, and these have exhibited cytotoxic activity against cancer cell lines as well as antimalarial activity. [ 23 ]…”