The browser you are using is not supported by this website. All versions of Internet Explorer are no longer supported, either by us or Microsoft (read more here: https://www.microsoft.com/en-us/microsoft-365/windows/end-of-ie-support).

Please use a modern browser to fully experience our website, such as the newest versions of Edge, Chrome, Firefox or Safari etc.

HUMAN ASPARTYLGLUCOSAMINIDASE - A BIOCHEMICAL AND IMMUNOCYTOCHEMICAL CHARACTERIZATION OF THE ENZYME IN NORMAL AND ASPARTYLGLUCOSAMINURIA FIBROBLASTS

På svenska

Author

  • N ENOMAA
  • T HEISKANEN
  • R HALILA
  • R SORMUNEN
  • R SEPPALA
  • Mauno Vihinen
  • L PELTONEN

Summary, in English

Aspartylglucosaminidase (AGA, EC 3.5.1.26) is an essential enzyme in the degradation of asparagine-linked glycoproteins. In man, deficient activity of this enzyme leads to aspartylglucosaminuria (AGU), a recessively inherited lysosomal storage disease. Here we used affinity-purified polyclonal antibodies against the native AGA and its denatured subunits to establish the molecular structure and intracellular location of the enzyme in normal and AGU fibroblasts. Inactivation of the enzyme was found to coincide with the dissociation of the heterodimeric enzyme complex into subunits. Although the subunits were not linked by covalent forces, the intrapolypeptide disulphide bridges were found to be essential for the normal function of AGA. AGA was localized into lysosomes in control fibroblasts by both immunofluorescence microscopy and immuno-electron microscopy, whereas in AGU cells the location of antigen was different, suggesting that, owing to the mutation, a missing disulphide bridge, most of the enzyme molecules get retarded in the cis-Golgi region and most probably face intracellular degradation.

Publishing year

1992

Language

English

Pages

613-618

Publication/Series

Biochemical Journal

Volume

286

Document type

Journal article

Publisher

Portland Press

Topic

  • Biochemistry and Molecular Biology

Status

Published

ISBN/ISSN/Other

  • ISSN: 0264-6021