A Thioredoxin Activated Glutamine Synthetase in Chlorella
نویسنده
چکیده
Glutam ine synthetase was partly purified from Chlorella pyrenoidosa. This enzyme activity was stimulated by dithioerythritol and 2'-3'-dimercaptopropanol (BAL). Full activation was obtained by thioredoxins isolated from the cyanobacterium Synechococcus 6301, from spinach and by heated Chlorella extract. The apparent Km for the purified thioredoxin B from Synechococcus 6301 was determined to be 0.022 (22 x 10~9 m), suggesting a specific role for thioredoxins in regulating glutamine synthetase activity in this alga.
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