Meta-Methylation of Flavonol Rings A (8-) and B (3'-) Is Catalysed by Two Distinct O-Methyltransferases
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چکیده
Lotus corniculatus, Leguminosae, O-Methyltransferase, Flavonols, 8-O-Methylation, 3'-0-Methylation Two O-methyltransferases specific for flavonol rings A and B were isolated from young flower buds of Lotus corniculatus. They were partially purified by ammonium sulphate precipitation and successive chromatography on Sephadex G-100 and Polybuffer ion exchanger. One enzyme focused at pi 5.5 and catalysed the O-methylation of position 8 of flavonols with a pH optimum of 8.1. The other enzyme had a pi of 5.1 and preferentially attacked position 3' at an optimum pH of 7.7. The methylated products of both enzymes seem to contribute to the flower colour of Lotus and may be used as biochemical markers in genetic studies of this genus.
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تاریخ انتشار 2013