• The Plant Pathology Journal
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• v.18 no.1
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• pp.18-22
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• 2002

Two peptaibol antibiotics, peptavirins A and B, which exhibited strong inhibitory effect against Tobacco mosaic vials (TMV) infection, were isolated from steam-cooked rice culture of Apiocrea sp.14T. The peptavirins were identified as new derivatives of chrysospermins, which are 19-mer and have been reported to be produced in a fungal isolate. The physicochemical properties of the peptavirins were mostly identical with chrysospermins A through D except for the UV absorption spectrum. The peptavirins inhibited the growths of the Grampositive bacteria tested, including the plant pathogenic bacterium, Corynebacterium lilium, and the fungus, Aspergillus niger. Peptavirin A was somewhat cytotoxic to cancer cell lines, especially K562 (leukemia) and UACC 62 (melanoma), whereas peptavirin B only exhibited slight cytotoxicity.

• Journal of Microbiology and Biotechnology
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• v.10 no.4
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• pp.522-528
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• 2000

A total of about 300 fungal isolates from forest havitats were screened for inhibitors of tobacco mosaic virus (TMV) infection using its local lesion host, Nicotiana tabacum cv. Xanthi nc. Ine of the isolates, 14T, showed a strong activity against TMV infection, and was identified as an Apiocrea sp. based on its morphological characterstics. Rice was an optimum culture medium for its fermentation, and two antiviral compounds, KGT 141 and KGT 142, were resolved from the rice culture through column chromatography, TLC, and HPLC. By NMR and FAB-MS, the two compounds were identified as chrysospermins B (KGT 141) and D (KGT 142), both of which are peptaibols with 19-mer amino acids possessing an acetylated N-terminus and a hydroxy-amino acid (tryptophanol) at the C-terminus. Both compounds showed inhibitory activities against TMV infection, but chrysospermin D showed the stronger activity than chrysospermin B. The former of $100{\;}\mu\textrm{g}/ml$ and 54.7% at $10{\;}\mu\textrm{g}/ml$, respectively. Furthermore, the chrysospermins were highly cytotoxic toward cancer cell lines of PC-3 (prostrate) and K562 (leukemia), and inhibited growth of the Gram-positive bacteria tested, especially the plant pathogenic bacterium Corynebacterium lilium. To the best of our knowledge, this is the first report on the inhibition of plant virus infection by antimicrobial peptaibols.