Multiple epoxide hydrolases in Alternaria alternata f. sp. lycopersici and their relationship to medium composition and host-specific toxin production.
نویسندگان
چکیده
The production of Alternaria alternata f. sp. lycopersici host-specific toxins (AAL toxins) and epoxide hydrolase (EH) activity were studied during the growth of this plant-pathogenic fungus in stationary liquid cultures. Media containing pectin as the primary carbon source displayed peaks of EH activity at day 4 and at day 12. When pectin was replaced by glucose, there was a single peak of EH activity at day 6. Partial characterization of the EH activities suggests the presence of three biochemically distinguishable EH activities. Two of them have a molecular mass of 25 kDa and a pI of 4.9, while the other has a molecular mass of 20 kDa and a pI of 4.7. Each of the EH activities can be distinguished by substrate preference and sensitivity to inhibitors. The EH activities present at day 6 (glucose) or day 12 (pectin) are concomitant with AAL toxin production.
منابع مشابه
Characterization of epoxide hydrolase activity in Alternaria alternata f. sp. lycopersici. Possible involvement in toxin production.
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ورودعنوان ژورنال:
- Applied and environmental microbiology
دوره 65 6 شماره
صفحات -
تاریخ انتشار 1999