Temperature-dependent hyper-activation of monoglucosyldiacylglycerol synthase is post-translationally regulated in Synechocystis sp. PCC 6803.
The mechanism of monoglucosyldiacylglycerol (MGlcDG) increase following heat shock in Synechocystis sp. PCC 6803 was examined by measuring MGlcDG synthase (Sll1377) activity. Temperature-dependent activation of Sll1377 was observed in the membrane fraction of Synechocystis sp. PCC 6803, whereas the Sll1377 protein level remained unchanged, suggesting that the activity is post-translationally regulated without covalent modification of Sll1377 by soluble enzymes. Four individual mutations introduced into recombinant Sll1377 (D147, D200, R329, and R331) significantly reduced the activity and blocked temperature-dependent activation, suggesting that these amino acid residues are essential for Sll1377 activity at both normal growth temperature and the higher temperature.
Shimojima
Mie
M
Research Center for the Evolving Earth and Planets, Tokyo Institute of Technology, 4259-B65 Nagatsuta-cho, Midori-ku, Yokohama 226-8501, Japan. mshimoji@bio.titech.ac.jp
Tsuchiya
Mami
M
Ohta
Hiroyuki
H
D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D002462:Cell Membrane / Q000201:enzymology; D004789:Enzyme Activation; D015964:Gene Expression Regulation, Bacterial; D015971:Gene Expression Regulation, Enzymologic; D005964:Glucosyltransferases / Q000235:genetics / Q000378:metabolism; D006017:Glycolipids / Q000378:metabolism; D006358:Hot Temperature; D009154:Mutation; D011499:Protein Processing, Post-Translational; D046939:Synechocystis / Q000201:enzymology / Q000235:genetics
D001426:Bacterial Proteins; D006017:Glycolipids; C014571:glucosyl diacylglycerol; D005964:Glucosyltransferases; C103660:1,2-diacylglycerol 3-glucosyltransferase