Accession Number:

ADA127059

Title:

Purification of N-Acetylgalactosaminidase by Isoelectric Focusing.

Descriptive Note:

Final rept.,

Corporate Author:

WAYNE STATE UNIV DETROIT MI DEPT OF BIOCHEMISTRY

Personal Author(s):

Report Date:

1983-04-02

Pagination or Media Count:

41.0

Abstract:

This is the final technical report on Contract N00014-78-C-0767 NR 207-143. This project was directed at obtaining and purifying enzymes which could convert type A human red blood cells to type O. The latter can be given to all recipients and the availability of such cells would simplify inventory and cross matching during emergencies. Chemically the A antigen differs from the O antigen only in that it has an additional terminal sugar residue, an alpha linked N acetylgalactostamine. Two enzymes have been studied which remove this residue and convert A substance to O substance. One of these Azymes, alpha-N-acetylgalactosaminidase, was from Clostridium perfringens and was studied in collaboration with Dr. David Aminoff at the University of Michigan. The chief emphasis of the work with Clostridial Azyme was its purification by isoelectric focusing. Any bacterial enzyme contaminating red cells after their conversion from A to O could cause serious immunologic reactions in recipients. Human enzymes were studied in attempts to avoid this potential problem. The human Azyme was prepared form placenta. The studies with placental Azyme concerned its purification, properties and development of an assay for its activity toward type A red blood cells. Although preliminary experiments have been done with Azyme treated type A red cells high background and variability make their interpretation uncertain. Monoclonal antibodies of higher specificity should improve the assay. The investigator appreciates the support from the Office of Naval Research. Author

Subject Categories:

  • Biochemistry
  • Medicine and Medical Research

Distribution Statement:

APPROVED FOR PUBLIC RELEASE