G. Tsuji, Toshiyuki Takeda, I. Furusawa
Mar 1, 1997
Citations
0
Influential Citations
45
Citations
Journal
Pesticide Biochemistry and Physiology
Abstract
Abstract Biosynthesis of melanin by Colletotrichum lagenarium is essential for appressorial penetration of its host plants. Carpropamid is a novel melanin-inhibiting fungicide for control of rice blast caused by Magnaporthe grisea. In C. lagenarium, appressorial and colonial melanization were inhibited by carpropamid. Accumulation of melanin intermediates, scytalone, was also shown in the culture medium containing carpropamid. One of the enzymes involved in the melanin biosynthesis, scytalone dehydratase catalyzes the conversion of scytalone to 1,3,8-trihydroxynaphthalene. We previously cloned SCD1 gene coding for scytalone dehydratase of C. lagenarium. In this study, a recombinant SCD1 expression vector was constructed using pMAL system and the recombinant scytalone dehydratase was purified from transformed Escherichia coli. Recombinant SCD1 showed scytalone dehydratase activity in an in vitro reaction using scytalone as substrate. The activity was assayed by measuring the production of 1,3,8-trihydroxynaphthalene or disappearance of scytalone, which was detectable by reverse-phase high-pressure liquid chromatography. Dehydration of scytalone to 1,3,8-trihydroxynaphthalene was inhibited by carpropamid in the in vitro reaction.