1887

Abstract

The effect of aflastatin A (AsA), a novel inhibitor of aflatoxin production, on melanin biosynthesis of was examined. Addition of a low concentration of AsA (05 μg ml) to the culture medium almost completely inhibited the melanin production of this organism. AsA also inhibited the production of scytalone, an early intermediate of melanin biosynthesis. Melanin production was restored by addition of exogenous scytalone in the presence of AsA, suggesting that the late steps after the synthesis of scytalone were not significantly affected by AsA. This was confirmed by the results from RT-PCR analysis of the expression of genes encoding melanin biosynthetic enzymes (, ) and a regulatory gene (). By contrast, expression of was severely impaired by AsA, although catalytic activity of a polyketide synthase (PKS1) was not inhibited by AsA. These results indicate that AsA inhibits an early step in melanin production, which suppresses the expression of

Loading

Article metrics loading...

/content/journal/micro/10.1099/00221287-147-9-2623
2001-09-01
2019-10-22
Loading full text...

Full text loading...

/deliver/fulltext/micro/147/9/1472623a.html?itemId=/content/journal/micro/10.1099/00221287-147-9-2623&mimeType=html&fmt=ahah

References

  1. Bell, A. A. & Wheeler, M. H. ( 1986; ). Biosynthesis and functions of fungal melanins. Annu Rev Phytopathol 24, 411-451.[CrossRef]
    [Google Scholar]
  2. Fujii, I., Mori, Y., Watanabe, A., Kubo, Y., Tsuji, G. & Ebizuka, Y. ( 1999; ). Heterologous expression and product identification of Colletotrichum lagenarium polyketide synthase encoded by the PKS1 gene involved in melanin biosynthesis. Biosci Biotechnol Biochem 63, 1445-1452.[CrossRef]
    [Google Scholar]
  3. Fujii, I., Mori, Y., Watanabe, A., Kubo, Y., Tsuji, G. & Ebizuka, Y. ( 2000; ). Enzymatic synthesis of 1,3,6,8-tetrahydroxynaphthalene solely from malonyl coenzyme A by a fungal iterative type I polyketide synthase PKS1. Biochemistry 39, 8853-8858.[CrossRef]
    [Google Scholar]
  4. Funa, N., Ohnishi, Y., Fujii, I., Shibuya, M., Ebizuka, Y. & Horinouchi, S. ( 1999; ). A new pathway for polyketide synthesis in microorganisms. Nature 400, 897-899.[CrossRef]
    [Google Scholar]
  5. Howard, R. J. & Ferrari, M. A. ( 1989; ). Role of melanin in appressorium formation. Exp Mycol 13, 403-418.[CrossRef]
    [Google Scholar]
  6. Ikeda, H., Matsumori, N., Ono, M., Suzuki, A., Isogai, A., Nagasawa, H. & Sakuda, S. ( 2000; ). Absolute configuration of aflastatin A, a specific inhibitor of aflatoxin production by Aspergillus parasiticus. J Org Chem 65, 438-444.[CrossRef]
    [Google Scholar]
  7. Kubo, Y. & Furusawa, I. ( 1991; ). Melanin biosynthesis: prerequisite for the successful invasion of the plant host by appressoria of Colletotrichum and Pyricularia. In The Fungal Spore and Disease Initiation in Plants and Animals , pp. 205-218. Edited by G. T. Cole & H. C. Hoch. New York:Plenum.
  8. Kubo, Y., Suzuki, K., Furusawa, I. & Yamamoto, M. ( 1983; ). Scytalone as a natural intermediate of melanin biosynthesis in appressoria of Colletotrichum lagenarium. Exp Mycol 7, 208-215.[CrossRef]
    [Google Scholar]
  9. Kubo, Y., Takano, Y., Endo, Y., Yasuda, N., Tajima, S. & Furusawa, I. ( 1996; ). Cloning and structural analysis of the melanin biosynthesis gene SCD1 encoding scytalone dehydratase in Colletotrichum lagenarium. Appl Environ Microbiol 62, 4340-4344.
    [Google Scholar]
  10. Ono, M., Sakuda, S., Suzuki, S. & Isogai, A. ( 1997; ). Aflastatin A, a novel inhibitor of aflatoxin production by aflatoxigenic fungi. J Antibiot 50, 111-118.[CrossRef]
    [Google Scholar]
  11. Ono, M., Sakuda, S., Ikeda, H., Furihata, K., Nakayama, J., Suzuki, A. & Isogai, A. ( 1998; ). Structures and biosynthesis of aflastatins: novel inhibitors of aflatoxin production by Aspergillus parasiticus. J Antibiot 51, 1019-1028.[CrossRef]
    [Google Scholar]
  12. Perpetua, N. S., Kubo, Y., Yasuda, N., Takano, Y. & Furusawa, I. ( 1996; ). Cloning and characterization of a melanin biosynthetic THR1 reductase gene essential for appressorial penetration of Colletotrichum lagenarium. Mol Plant–Microbe Interact 9, 323-329.[CrossRef]
    [Google Scholar]
  13. Sakuda, S., Ono, M., Furihata, K., Nakayama, J., Suzuki, A. & Isogai, A. ( 1996; ). Aflastatin A, a novel inhibitor of aflatoxin production of Aspergillus parasiticus, from Streptomyces. J Am Chem Soc 118, 7855-7856.[CrossRef]
    [Google Scholar]
  14. Takano, Y., Kubo, Y., Shimizu, K., Mise, K., Okuno, T. & Furusawa, I. ( 1995; ). Structural analysis of PKS1, a polyketide synthase gene involved in melanin biosynthesis of Colletotrichum lagenarium. Mol Gen Genet 249, 162-167.[CrossRef]
    [Google Scholar]
  15. Tsuji, G., Kenmochi, Y., Takano, Y., Sweigard, J., Farrall, L., Furusawa, I., Horino, O. & Kubo, I. ( 2000; ). Novel fungal transcriptional activators, Cmr1o of Colletotrichum lagenarium and Pig1p of Magnaporthe grisea, contain Cys2His2 zinc finger and Zn(II)2Cys6 binuclear cluster DNA-binding motifs and regulate transcription of melanin biosynthesis genes in a developmentally specific manner. Mol Microbiol 38, 940-954.
    [Google Scholar]
  16. Yamaguchi, I. & Kubo, Y. ( 1992; ). Target sites of melanin biosynthesis inhibitors. In Target Sites of Fungicide Action , pp. 101-118. Edited by W. Koller. Boca Raton, FL:CRC Press.
http://instance.metastore.ingenta.com/content/journal/micro/10.1099/00221287-147-9-2623
Loading
/content/journal/micro/10.1099/00221287-147-9-2623
Loading

Data & Media loading...

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error