title: Formation of alpha-1,2- and alpha-1,3-linked mannose disaccharides from mannosyl retinyl phosphate by rat liver membrane enzymes.
abstract: Mannosyl retinyl phosphate (MRP) was an active substrate for the transfer of mannose to methyl-alpha-D-mannose (CH3-alpha-man), p-nitrophenyl-alpha-D-mannose, and free mannose. The products formed during MRP incubation with CH3-alpha-man or with mannose were alpha-linked. The disaccharides formed by incubation of MRP with mannose were identified by paper chromatography and electrophoresis as mannose-alpha-1,2-mannose and mannose-alpha-1,3-mannose. Triton X-100 greatly inhibited mannose-alpha-1,3-mannose synthesis. In the absence of detergent, MnCl2, NiCl2, and ZnCl2 inhibited synthesis of both products. Formation of mannose-alpha-1,3-mannose was more sensitive to preincubation of the enzyme at 40 degrees C then was synthesis of mannose-alpha-1,2-mannose. No differences in membrane mannosyltransferase activity with MRP, compared to DMP, could be demonstrated.
mesh_terms: D000818:Animals; D002462:Cell Membrane / Q000201:enzymology; D004187:Disaccharides / Q000096:biosynthesis*; D004224:Diterpenes; D006600:Hexosephosphates / Q000378:metabolism*; D006602:Hexosyltransferases / Q000378:metabolism*; D008099:Liver / Q000201:enzymology*; D008297:Male; D008360:Mannosephosphates / Q000378:metabolism*; D008361:Mannosidases; D008364:Mannosyltransferases / Q000378:metabolism*; D011103:Polyisoprenyl Phosphate Monosaccharides / Q000378:metabolism*; D011105:Polyisoprenyl Phosphate Sugars / Q000378:metabolism*; D051381:Rats
chemical_list: D004187:Disaccharides; D004224:Diterpenes; D006600:Hexosephosphates; D008360:Mannosephosphates; D011103:Polyisoprenyl Phosphate Monosaccharides; D011105:Polyisoprenyl Phosphate Sugars; C013101:mannosylretinylphosphate; D006602:Hexosyltransferases; D008364:Mannosyltransferases; D008361:Mannosidases