Melanine biosynthesis inhibitors

Another group of fungicides interferes with cell wall formation. Two examples of this group include 1) the polyoxines, which prevent chitin formation by competitively inhibiting chitin-synthase, the final enzyme involved in chitin biosynthesis, and 2) melanine biosynthesis inhibitors, especially in Pyricularia oryzae. Examples of... 

Melanin Biosynthesis Inhibitors. Among the most desirable targets for selective fungitoxic action are those uniquely associated with fungal pathogenicity such as the polyketide pathway to melanin in the fungus Pyricularia oryzae which causes rice blast disease. 

Utilizing knowledge concerning the structural relationship of known melanin biosynthesis inhibitors (MBI) to 1,3,8-trihydroxynaphthalene (1,3,8-THN), the substrate of a target enzyme in this pathway, Omata et al. (58) have recently designed phthalazine derivatives that are good MBI and rice blast control agents. 

Reductase in melanin biosynthesis (MBI-R) Melanin biosynthesis inhibitors Triqfdazole Specific for rice blast... 

Although we have accumulated a lot of experience since the practical problem of fungicide resistance first occurred in the early 1970 s, the recent outbreaks of resistance to Qols and MBI-Ds (melanin biosynthesis inhibitors, vAiich target scytalone dehydratase) demonstrated how resistance management is still difficult to achieve. 

Very recently, furthermore, the new problem of resistance against melanin biosynthesis inhibitors, which target scyta lone dehydratase (MBI-D), has also occurred in rice blast fungus in Japan (6). 

Thines, E., T. Daupmann, M. Semar, O. Sterner H. Anke. 1995. Fungal melanin biosynthesis inhibitors introduction of a test system based on the production of dihy-droxynaphthalene (DHN) melanin in agar cultures. Z. Naturforsch. 50c 1-7. 

Yamaguchi, I. Y. Kubo. 1992. Target sites of melanin biosynthesis inhibitors. In Target Sites of Fungicide Action, ed. W. Koller, pp. 101-118, CRC Press, Boca Raton, FL. 

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