Lysine-ketoglutarate reductase activity in developing maize endosperm.
نویسندگان
چکیده
Lysine-ketoglutarate reductase activity was detected and characterized in the developing endosperm of maize (Zea mays L.). The enzyme showed specificity for its substrates: lysine, alpha-ketoglutarate, and NADPH. Formation of the reaction product saccharopine was demonstrated. The pH optimum of the enzyme was close to 7, and the K(m) for lysine and alpha-ketoglutarate were 5.2 and 1.8 millimolar, respectively.
منابع مشابه
Lysine-Ketoglutarate Reductase in Normal and Opaque-2 Maize Endosperms'
Lysine-ketoglutarate reductase catalyzes the first step of lysine catabolism in maize (Zea mays L.) endosperm. The enzyme condenses L-lysine and a-ketoglutarate into saccharopine using NADPH as cofactor. It is endosperm-specific and has a temporal pattern of activity, increasing with the onset of kernel development, reaching a peak 20 to 25 days after pollination, and thereafter decreasing as t...
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Lysine-ketoglutarate reductase catalyzes the first step of lysine catabolism in maize (Zea mays L.) endosperm. The enzyme condenses l-lysine and alpha-ketoglutarate into saccharopine using NADPH as cofactor. It is endosperm-specific and has a temporal pattern of activity, increasing with the onset of kernel development, reaching a peak 20 to 25 days after pollination, and there-after decreasing...
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The first enzyme of the lysine degradation pathway in maize (Zea mays L.), lysine-ketoglutarate reductase, condenses lysine and [alpha]-ketoglutarate into saccharopine using NADPH as a cofactor, whereas the second, saccharopine dehydrogenase, converts saccharopine to [alpha]-aminoadipic-[delta]-semialdehyde and glutamic acid using NAD+ or NADP+ as a cofactor. The reductase and dehydrogenase act...
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ورودعنوان ژورنال:
- Plant physiology
دوره 69 4 شماره
صفحات -
تاریخ انتشار 1982