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Lysosomal neuraminidase from human placenta has been obtained in its active form by association of an inactive neuraminidase polypeptide with beta-galactosidase and the protective protein. Using a specific antiserum, we have now identified a 66-kDa protein as the inactive neuraminidase polypeptide. It is specifically recognized on immunoblots only in its nonreduced state, and it coprecipitates with neuraminidase activity. The 66-kDa polypeptide is substantially glycosylated (38-kDa protein core with 7-14 N-linked oligosaccharide chains), a feature characteristic of lysosomal integral membrane proteins. Specific removal of the 66-kDa neuraminidase polypeptide from glycoprotein preparations prevents the generation of neuraminidase activity. Removal of beta-galactosidase or destruction of the protective protein also hinders the formation of active neuraminidase. Reconstitution of neuraminidase activity is observed after mixing glycoprotein preparations, depleted in different components of the beta-galactosidase-neuraminidase-protective protein complex, indicating that all three components of the complex are required for neuraminidase activity. Association of the neuraminidase polypeptide and the protective protein generates unstable neuraminidase activity, whereas association with beta-galactosidase is required for stability.
G T van der Horst, and
N J Galjart, and
A d'Azzo, and
H Galjaard, and
F W Verheijen
January 1987,
European journal of biochemistry,
G T van der Horst, and
N J Galjart, and
A d'Azzo, and
H Galjaard, and
F W Verheijen
September 1977,
Life sciences,
G T van der Horst, and
N J Galjart, and
A d'Azzo, and
H Galjaard, and
F W Verheijen
June 1972,
The Biochemical journal,
G T van der Horst, and
N J Galjart, and
A d'Azzo, and
H Galjaard, and
F W Verheijen
November 2004,
Nihon rinsho. Japanese journal of clinical medicine,
G T van der Horst, and
N J Galjart, and
A d'Azzo, and
H Galjaard, and
F W Verheijen
December 1988,
Indian journal of biochemistry & biophysics,
G T van der Horst, and
N J Galjart, and
A d'Azzo, and
H Galjaard, and
F W Verheijen
February 1996,
European journal of cell biology,
G T van der Horst, and
N J Galjart, and
A d'Azzo, and
H Galjaard, and
F W Verheijen
August 2008,
Bioscience reports,
G T van der Horst, and
N J Galjart, and
A d'Azzo, and
H Galjaard, and
F W Verheijen
November 1998,
Placenta,
G T van der Horst, and
N J Galjart, and
A d'Azzo, and
H Galjaard, and
F W Verheijen
November 1990,
Biochemical and biophysical research communications,
G T van der Horst, and
N J Galjart, and
A d'Azzo, and
H Galjaard, and
F W Verheijen
January 2007,
FEBS letters,
