The Incorporation of [1,2-13C2] Acetate into Pisatin to Establish the Biosynthesis of Its Polyketide Moiety *
نویسندگان
چکیده
Biosynthesis, 13C-NMR, Phytoalexins, Pisatin The biosynthesis of the polyketide moiety in pisatin has been examined by incorporation ex periments with [1,2-13C2] acetate and 13C-NMR measurements. The results establish that the C-5 carbonyl group in the enzyme-bound, open-chain polyketide precursor is reduced before cyclization to form the aryl ring. The specific incorporation attained in these experiments was considerably higher than that reported for earlier studies using singly labelled, radioactive acetate, emphasizing the importance of the timing of precursor addition.
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