Biosynthesis of dolichyl pyrophosphate N-acetylglucosaminyl intermediates in liver microsomes from hibernating ground squirrels (Citellus citellus L.).
Dolichyl pyrophosphate N-acetyl[14C]glucosamine was synthesized after incubation of liver microsomes from hibernating ground squirrels with UDP-N-acetyl[14C )glucosamine. The radioactivity of glycolipid formed by liver microsomes from hibernating ground squirrels was about 2-fold greater than by liver microsomes from active animals. Addition of exogenous dolichyl phosphate to the incubation mixture increased the formation of dolichyl pyrophosphate N-acetyl[14C]glucosamine by microsomes from both active and hibernating ground squirrels about 6 times. Liver microsomes from hibernating ground squirrels converted dolichyl pyrophosphate N-acetyl[14C]glucosamine into dolichyl pyrophosphate N,N'-diacetyl[14C]chitobiose in the presence of unlabelled UDP-N-acetylglucosamine. This conversion was maximal at 1.0 M concentration of unlabelled UDP-N-acetylglucosamine. The level of dolichyl phosphate assessed by the level of dolichyl pyrophosphate N-acetylglucosamine formation was nearly 2 times greater in liver microsomes from hibernating ground squirrels than from active animals.
D000818:Animals; D002854:Chromatography, Paper; D005260:Female; D005964:Glucosyltransferases / Q000378:metabolism; D006605:Hibernation; D006868:Hydrolysis; D066298:In Vitro Techniques; D008297:Male; D008862:Microsomes, Liver / Q000378:metabolism*; D017351:N-Acetylglucosaminyltransferases; D011103:Polyisoprenyl Phosphate Monosaccharides / Q000096:biosynthesis*; D011104:Polyisoprenyl Phosphate Oligosaccharides / Q000096:biosynthesis*; D011105:Polyisoprenyl Phosphate Sugars / Q000096:biosynthesis*; D012589:Sciuridae / Q000378:metabolism*
D011103:Polyisoprenyl Phosphate Monosaccharides; D011104:Polyisoprenyl Phosphate Oligosaccharides; D011105:Polyisoprenyl Phosphate Sugars; C018439:N-acetylglucosaminylpyrophosphoryldolichol; C016418:dolichyl-diphosphate-di-N-acetylchitobiose; D005964:Glucosyltransferases; D017351:N-Acetylglucosaminyltransferases; C037649:N-acetyllactosaminide beta-1,6-N-acetylglucosaminyltransferase