title: New metabolic pathway for converting blasticidin S in Aspergillus flavus and inhibitory activity of aflatoxin production by blasticidin S metabolites.
abstract: Blasticidin S, a protein synthesis inhibitor, inhibits aflatoxin production of Aspergillus flavus without affecting fungal growth. Analysis of metabolites in blasticidin S-treated A. flavus using quadrupole time-of-flight liquid chromatography-mass spectrometry showed that blasticidin S was metabolized into a novel metabolite, N-acetyldeaminohydroxyblasticidin S. Conversion of blasticidin S to N-acetyldeaminohydroxyblasticidin S via deaminohydroxyblasticidin S or N-acetylblasticidin S was observed in in vivo and in vitro A. flavus systems. Blasticidin S and N-acetylblasticidin S inhibited the growth of Aspergillus niger strongly and weakly, respectively, but deaminohydroxyblasticidin S and N-acetyldeaminohydroxyblasticidin S did not inhibit its growth. On the other hand, deaminohydroxyblasticidin S sustained the inhibition of aflatoxin production whereas N-acetylblasticidin S and N-acetyldeaminohydroxyblasticidin S did not. These results suggest that the free amino group at C-13 of blasticidin S and deaminohydroxyblasticidin S may be important for the inhibitory activity of aflatoxin production.
authors.affiliation: National Institute of Health Sciences, Setagaya-ku, Tokyo, Japan. t-yoshinari@nihs.go.jp
authors.forename: Tomoya
authors.initials: T
authors.lastname: Yoshinari
authors.forename: Shohei
authors.initials: S
authors.lastname: Sakuda
authors.forename: Maiko
authors.initials: M
authors.lastname: Watanabe
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Kamata
authors.forename: Takahiro
authors.initials: T
authors.lastname: Ohnishi
authors.forename: Yoshiko
authors.initials: Y
authors.lastname: Sugita-Konishi
mesh_terms: D016604:Aflatoxin B1 / Q000037:antagonists & inhibitors / Q000378:metabolism*; D001231:Aspergillus flavus / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism*; D001234:Aspergillus niger / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism; D013058:Mass Spectrometry; D053858:Metabolic Networks and Pathways; D009705:Nucleosides / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology
chemical_list: D009705:Nucleosides; C004500:blasticidin S; D016604:Aflatoxin B1