title: Photolabeling of the alpha-neuraminidase/beta-galactosidase complex from human placenta with a photoreactive neuraminidase inhibitor.
abstract: Photolabeling of the alpha-neuraminidase/beta-galactosidase complex in human placenta (Verheijen, F.W. et al (1987) Eur. J. Biochem. 162, 63-67) was carried out using the radioactive photoprobe, 9-S-(4-azido-3,5-3H-2-nitrophenyl)-5-acetamido-2,6 anhydro-2,3,5,9- tetradeoxy-9- thio-D-glycero-D-galacto-non-2-enonic acid. Two intensely labeled bands at 61 and 46 kD were detected with autoradiography. Labeling of the 46 kD protein was blocked with the inclusion of the surfactant Triton X-100 in the photolysis mixture, indicating a nonspecific, hydrophobic interaction. The 61 kD protein was protected from labeling only when the neuraminidase inhibitor 2,3 dehydro N-acetyl neuraminic acid (1 mM) was present during photolysis. These results suggest that the neuraminidase activity resides among the proteins in the 61 kD molecular weight range comigrating with the lysosomal beta-galactosidase, under denaturing conditions.
authors: Department of Pediatrics, University of Tennessee, Memphis.
authors: T G
authors: TG
authors: Warner
authors: A
authors: A
authors: Louie
authors: M
authors: M
authors: Potier
mesh_terms: D000345:Affinity Labels / Q000378:metabolism*; D000595:Amino Acid Sequence; D001345:Autoradiography; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D006801:Humans; D007256:Information Systems; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009097:Multienzyme Complexes / Q000302:isolation & purification / Q000378:metabolism*; D009439:Neuraminidase / Q000302:isolation & purification / Q000378:metabolism*; D010782:Photolysis; D010920:Placenta / Q000201:enzymology*; D011247:Pregnancy; D012794:Sialic Acids / Q000138:chemical synthesis / Q000378:metabolism*; D014316:Tritium
chemical_list: D000345:Affinity Labels; D009097:Multienzyme Complexes; D012794:Sialic Acids; D014316:Tritium; C066536:9-(4-azido-2-nitrophenyl)-5-acetamido-2,6-anhydro-2,3,5,9-tetradeoxy-9-thioglycerogalactonon-2-enoic acid; D009439:Neuraminidase