Characterization and Solubilization of β-Glucan Synthases from Cultured Rice Cells.
Two types of β-glucan synthases, GS-I and GS-II, were found in cultured rice cells (Oryza sativa L.). In glycerol density gradient centrifugation, GS-I activity peak co-migrated with a marker enzyme of the Golgi membrane, while GS-II co-migrated with the plasma membrane. Analysis of the reaction products of GS-I and GS-II, suggested that GS-I and GS-II were mainly β-1,4,- and β-1,3-glucosyltransferases, respectively. GS-I had a higher substrate affinity for UDP-glucose than GS-II, and needed divalent cations for its activity. Effects of nucleotides on the activity were also considerably different between GS-I and GS-II. GS-I was solubilized well with CHAPS and digitonin, and GS-II was solubilized effectively with sucrose monolaurate.
a Department of Biosystem Science , Graduate School of Science and Technology.
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Kuribayashi
a Department of Biosystem Science , Graduate School of Science and Technology.
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Kimura
a Department of Biosystem Science , Graduate School of Science and Technology.|b Department of Agricultural Chemistry, Faculty of Agriculture , Niigata University , 2-Ikarashi, Niigata 950-21 , Japan.
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Morita
a Department of Biosystem Science , Graduate School of Science and Technology.|b Department of Agricultural Chemistry, Faculty of Agriculture , Niigata University , 2-Ikarashi, Niigata 950-21 , Japan.
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Igaue