Phosphatidylinositol kinase in rat mast cell granules

Journal Article · Wed Jan 01 00:00:00 EST 1986 · J. Immunol.; (United States)

OSTI ID:6936481

Kurosawa, M; Parker, C W

Intact granules were isolated from sonicated purified rat serosal mast cells on a Percoll gradient. The granules were shown to contain a highly active phosphatidylinositol kinase that catalyzes the formation of diphosphoinositide from endogenous phosphatidylinositol in the granule membrane. The enzyme requires ATP and Mg/sup 2 +/ or Mn/sup 2 +/ for activity; Ca/sup 2 +/, fluoride and cyclic AMP are inhibitory. The K/sub m/ for ATP is 25 ..mu..M. The initial reaction is rapid, but the response ceases within a few minutes. A comparison of the rate of phosphorylation of intact and broken membrane granules suggests that the phosphorylation occurs on the outer (cytoplasmic) surface of the granules.

• Research Organization: Washington Univ. School of Medicine, St. Louis, MO
• OSTI ID: 6936481
• Journal Information: J. Immunol.; (United States), Vol. 136:2
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
PHOSPHOTRANSFERASES
BIOCHEMICAL REACTION KINETICS
CELL MEMBRANES
DYNAMIC FUNCTION STUDIES
LABELLED COMPOUNDS
LABELLING
MAST CELLS
PHOSPHORUS 32
RATS
SEDIMENTATION
ANIMAL CELLS
ANIMALS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
CELL CONSTITUENTS
CONNECTIVE TISSUE CELLS
DAYS LIVING RADIOISOTOPES
ENZYMES
ISOTOPES
KINETICS
LIGHT NUCLEI
MAMMALS
MEMBRANES
NUCLEI
ODD-ODD NUCLEI
PHOSPHORUS ISOTOPES
PHOSPHORUS-GROUP TRANSFERASES
RADIOISOTOPES
REACTION KINETICS
RODENTS
SOMATIC CELLS
TRANSFERASES
VERTEBRATES
550201* - Biochemistry- Tracer Techniques