Isolation and characterization of a serine proteinase specific to human C3b from human erythrocyte membranes
In a previous report, they have shown that human C3b bound through CR1 to human erythrocytes is cleaved by a membrane proteinase activity. Following the molecular analysis of this proteinase activity, they have purified it by a four step procedure: ammonium sulfate precipitation, biogel filtration, fluid phase electrophoresis and hydroxylapatite chromatography. The highly purified proteinase was labeled by /sup 125/I iodine or /sup 3/H-DFP and analyzed by gel electrophoresis: a single band membrane component was characterized by its apparent molecular weight of 57 K or 60 K, under non reducing or reducing conditions respectively and was called p 57. Its reactivity with /sup 3/H-DFP and the inhibition by PMSF of the proteinase activity indicate that p 57 is a serine proteinase. Moreover, it is sensitive to aprotinin and ..gamma..1-antitrypsin. This membrane proteinase presents a higher activity in the presence of detergent and cleaves both alpha and beta chains of human C3b. Polyclonal antibody prepared against this purified proteinase inhibits its activity. On the basis of its structure and its functions, i.e. molecular weight, antigenic properties, proteinase properties and proteinases inhibitors sensitivity, p57 is not related to CR1 or DAF, two others membrane components which react with human C3b and identified by others on human erythrocytes. These specific antibodies allow to analyze the presence of p57 on human cells.
- Research Organization:
- Laboratoire de Biochimie des Antigens de Membrane, Creteil, France
- OSTI ID:
- 7092685
- Report Number(s):
- CONF-8604222-
- Journal Information:
- Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States), Vol. 45:4; Conference: 70. annual meeting of the Federation of American Society for Experimental Biology, St. Louis, MO, USA, 13 Apr 1986
- Country of Publication:
- United States
- Language:
- English
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COMPLEMENT
MOLECULAR BIOLOGY
SERINE PROTEINASES
PURIFICATION
CELL MEMBRANES
ERYTHROCYTES
IODINE 125
MAN
TRACER TECHNIQUES
TRITIUM COMPOUNDS
ANIMALS
BETA DECAY RADIOISOTOPES
BIOLOGICAL MATERIALS
BLOOD
BLOOD CELLS
BODY FLUIDS
CELL CONSTITUENTS
DAYS LIVING RADIOISOTOPES
ELECTRON CAPTURE RADIOISOTOPES
ENZYMES
HYDROLASES
INTERMEDIATE MASS NUCLEI
IODINE ISOTOPES
ISOTOPE APPLICATIONS
ISOTOPES
LABELLED COMPOUNDS
MAMMALS
MATERIALS
MEMBRANES
NUCLEI
ODD-EVEN NUCLEI
PEPTIDE HYDROLASES
PRIMATES
RADIOISOTOPES
VERTEBRATES
550201* - Biochemistry- Tracer Techniques