THE 9.5 A RESOLUTION STRUCTURE OF GLUTAMATE SYNTHASE FROM CRYO-ELECTRON MICROSCOPY AND ITS OLIGOMERIZATION BEHAVIOR IN SOLUTION: FUNCTIONAL IMPLICATIONS. 2VDC OXIDOREDUCTASE, AMIDOTRANSFERASE, AMMONIA ASSIMILATION, NADP, IRON, ZYMOGEN, NADPH-DEPENDENT GLUTAMATE SYNTHASE, IRON SULPHUR FLAVOPROTEIN, GLUTAMINE AMIDOTRANSFERASE, GLUTAMATE BIOSYNTHESIS, AMINO-ACID BIOSYNTHESIS