Evidence that the platinum-reactive methionyl residue of the. cap alpha. /sub 2/-macroglobulin receptor recognition site is not in the carboxyl-terminal receptor binding domain
Digestion of human ..cap alpha../sub 2/-macroglobulin-methylamine with papain prior to gel filtration resulted in the resolution of three distinct peaks. The material in peak I and peak II did not have any receptor binding ability as determined by in vivo clearance studies and in vitro competitive binding studies using mouse peritoneal macrophages. In contrast, the material in peak III bound to macrophage ..cap alpha../sub 2/-macroglobulin receptors with a K/sub d/ of 250 nM. This represents a 500-fold decrease in affinity relative to undigested ..cap alpha../sub 2/M-CH/sub 3/NH/sub 2/. Sequence analysis demonstrated that this material constituted the carboxyl-terminal fragment (COOH-terminal fragment) of ..cap alpha../sub 2/M. ..cap alpha../sub 2/M is known to possess a methionyl residue which is susceptible to modification by cis-dichlorodiammineplatinum (II) (cis-DDP) with the result being a loss of receptor binding ability by ..cap alpha../sub 2/M. For this reason, experiments were performed to determine if the platinum-reactive methionyl residue is located in the COOH-terminal receptor binding fragment of ..cap alpha../sub 2/M. The results of this investigation demonstrate that cis-DDP is not reactive with either the isolated COOH-terminal fragment or the COOH-terminal fragment isolated from ..cap alpha../sub 2/M-CH/sub 3/NH/sub 2/ which had been pretreated with cis-DDP. In addition, the COOH-terminal fragment did not bind to monoclonal antibody 7H11D6, a monoclonal antibody which binds to the platinum-reactive epitope of the ..cap alpha../sub 2/M-CH/sub 3/NH/sub 2/ receptor recognition site. The results of this investigation demonstrate that this fragment is not the complete receptor recognition site and suggest that a platinum-reactive methionyl residue located in the 55-kDa fragment of ..cap alpha../sub 2/M is another component of this site.
- Research Organization:
- Duke Univ. Medical Center, Durham, NC (USA)
- OSTI ID:
- 6834689
- Journal Information:
- J. Biol. Chem.; (United States), Journal Name: J. Biol. Chem.; (United States) Vol. 263:14; ISSN JBCHA
- Country of Publication:
- United States
- Language:
- English
Similar Records
Monoclonal antibodies to DNA modified with cis- or trans-diamminedichloroplatinum(II)
Proteolysis of human. cap alpha. /sub 2/-macroglobulin without hydrolysis of the internal thiolesters or expression of the receptor recognition site
Related Subjects
560300* -- Chemicals Metabolism & Toxicology
62 RADIOLOGY AND NUCLEAR MEDICINE
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ALKALI METAL COMPOUNDS
AMINO ACID SEQUENCE
AMINO ACIDS
ANIMAL CELLS
ANIMALS
ANTIBODIES
BETA DECAY RADIOISOTOPES
BIOLOGICAL EFFECTS
CARBOXYLIC ACIDS
CONFIGURATION INTERACTION
CONNECTIVE TISSUE CELLS
DAYS LIVING RADIOISOTOPES
DRUGS
ELECTRON CAPTURE RADIOISOTOPES
ELECTROPHORESIS
GLOBULINS
HALIDES
HALOGEN COMPOUNDS
IMMUNOASSAY
IMMUNOLOGY
INORGANIC PHOSPHORS
INTERMEDIATE MASS NUCLEI
IODIDES
IODINE 125
IODINE COMPOUNDS
IODINE ISOTOPES
ISOTOPE APPLICATIONS
ISOTOPES
LIPOTROPIC FACTORS
MACROPHAGES
MAMMALS
MAN
MEMBRANE PROTEINS
METHIONINE
MOLECULAR STRUCTURE
MONOCLONAL ANTIBODIES
NUCLEI
ODD-EVEN NUCLEI
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC SULFUR COMPOUNDS
PHAGOCYTES
PHOSPHORS
PLATINUM COMPOUNDS
PRIMATES
PROTEINS
RADIOASSAY
RADIOIMMUNOASSAY
RADIOIMMUNOLOGY
RADIOISOTOPES
RECEPTORS
SODIUM COMPOUNDS
SODIUM IODIDES
SOMATIC CELLS
TRACER TECHNIQUES
TRANSITION ELEMENT COMPOUNDS
VERTEBRATES