title: Hexosamine metabolism during spherule formation in Physarum polycephalum.
abstract: Hexosamine metabolism in relation to the spherule-wall synthesis in Physarum polycephalum was studied by the incorporation of labeled sugar into the wall and intermediary compounds in the biosynthesis of wall polysaccharide. The incorporation of [14C]galactosamine into the wall material occurred after a lag period of about 10 h in an induction medium. Nucleotides and sugar phosphates in the acid-soluble fraction of spherulating plasmodia were analyzed by column chromatography on Dowex 1-X8 (formate). The primary labeled products formed in the spherulating plasmodia after incubation with [14C]galactosamine were galactosamine 1-phosphate, UDP-galactosamine, N-acetylhexosamine 6-phosphate and UDP-N-acetylhexosamine. Spherulation was insensitive to polyoxin D, while it was completely blocked by cycloheximide. The activity of galactokinase and galactose-1-phosphate uridyltransferase increased 4--5-fold during the spherulation.
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D002473:Cell Wall / Q000378:metabolism; D002478:Cells, Cultured; D002845:Chromatography / Q000379:methods; D005686:Galactokinase / Q000378:metabolism; D005688:Galactosamine / Q000378:metabolism; D006595:Hexosamines / Q000378:metabolism*; D010804:Physarum / Q000378:metabolism* / Q000648:ultrastructure; D012995:Solubility; D005694:UTP-Hexose-1-Phosphate Uridylyltransferase / Q000378:metabolism
chemical_list: D000900:Anti-Bacterial Agents; D006595:Hexosamines; D005688:Galactosamine; D005686:Galactokinase; D005694:UTP-Hexose-1-Phosphate Uridylyltransferase