title: Circular dichroism changes in galactosyltransferase upon substrate binding;.
abstract: Circular dichroism studies with the galactosyltransferase isolated from bovine skim milk are described. Addition of UDP-galactose to the galactosyltransferase-Mn-2+ complex causes a decrease in the negative mean residue ellipticity in the 205-220-nm range and positive increases in the 265- and 275-290-nm ellipticity. These date are consistent with the view that a conformation change involving aromatic amino acid residues occurs upon the binding of UDP-galactose to the galactosyltransferase-Mn-2+ complex. No effects in the near-ultraviolet circular dichroism spectrum were observed upon the addition of UDP or glucose to the galactosyltransferase-Mn-2+ complex.
mesh_terms: D000818:Animals; D001665:Binding Sites; D002417:Cattle; D002942:Circular Dichroism; D005260:Female; D005690:Galactose; D006602:Hexosyltransferases / Q000378:metabolism; D007700:Kinetics; D008345:Manganese; D008892:Milk / Q000201:enzymology; D011485:Protein Binding; D011487:Protein Conformation; D013056:Spectrophotometry, Ultraviolet; D014539:Uridine Diphosphate Sugars
chemical_list: D014539:Uridine Diphosphate Sugars; D008345:Manganese; D006602:Hexosyltransferases; D005690:Galactose