Glutamine Synthetase Isoenzymes in the Green Soil Alga Stichococcus bacillaris Naeg.

نویسندگان

  • I Ahmad
  • J A Hellebust
چکیده

Two forms of glutamine synthetase (GS(1) and GS(2)) have been separated from cells of Stichococcus bacillaris by fast protein liquid chromatography. The activities of the two isoenzymes were influenced by the composition of the media employed; thiol reagents were essential for stabilizing GS(2) but they suppressed GS(1) activity. The activity of each isoenzyme was, therefore, determined following separate purification procedures. Growth conditions influenced both isoenzymes; GS(2) showed maximum activity under photoautotrophic conditions, whereas GS(1) showed maximum activity under heterotrophic conditions.

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عنوان ژورنال:
  • Plant physiology

دوره 83 2  شماره 

صفحات  -

تاریخ انتشار 1987