Mechanism of the influence of EGTA on the affinity of the Ca-transporting and Ca-binding systems of the cell for calcium
The activity of Ca-ATPases of erythrocyte ghosts and the sarcoplasmic reticulum, as the rate of ATP-dependent uptake of /sup 44/Ca by inside-out vesicles of erythrocyte membranes, vesicles of sarcoplasmic reticulum and mitochondria, was investigated. Evidently in all cases, the introduction of EGTA into the incubation medium leads to an increase in the affinity of the Ca-pumps for Ca/sup 2 +/ without any change in their maximum activity. An analogous effect of EGTA was detected in a determination of the affinity of Ca/sup 2 +/ of calmodulin, troponin S, and the fluorescent dye quin 2. It is suggested that the action of EGTA on the affinity of the Ca-transporting and Ca-binding systems of the cell for Ca/sup 2 +/ is associated with displacement of impurities of di- and trivalent cations.
- Research Organization:
- Ministry of Health of the USSR, Moscow
- OSTI ID:
- 5933507
- Journal Information:
- Biochemistry (Engl. Transl.); (United States), Journal Name: Biochemistry (Engl. Transl.); (United States) Vol. 50:11; ISSN BIORA
- Country of Publication:
- United States
- Language:
- English
Similar Records
A high-affinity Ca{sup 2+} pump, ECA1, from the endoplasmic reticulum is inhibited by cyclopiazonic acid but not by thapsigargin
Existence of a low-affinity ATP-binding site in the unphosphorylated Ca sup 2+ -ATPase of sarcoplasmic reticulum vesicles: Evidence from binding of 2 prime ,3 prime -O-(2,4,6-trinitrocyclohexadienylidene)-( sup 3 H)AMP and -( sup 3 H)ATP
Related Subjects
550301* -- Cytology-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ACID ANHYDRASES
ALCOHOLS
ALKALINE EARTH ISOTOPES
ALKALINE EARTH METAL COMPOUNDS
ANIMAL CELLS
ANIMALS
ATP-ASE
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOCHEMISTRY
BIOLOGICAL EFFECTS
BIOLOGICAL MATERIALS
BLOOD
BLOOD CELLS
BODY FLUIDS
CALCIUM 45
CALCIUM COMPOUNDS
CALCIUM ISOTOPES
CARBOXYLIC ACIDS
CELL CONSTITUENTS
CELL MEMBRANES
CHELATING AGENTS
CHEMISTRY
DAYS LIVING RADIOISOTOPES
EGTA
ENZYME ACTIVITY
ENZYMES
ERYTHROCYTES
EVEN-ODD NUCLEI
GLYCOLS
HYDROLASES
HYDROXY COMPOUNDS
INTERMEDIATE MASS NUCLEI
ION EXCHANGE
ISOTOPE APPLICATIONS
ISOTOPES
LABELLED COMPOUNDS
LIVER CELLS
MAMMALS
MATERIALS
MEMBRANE PROTEINS
MEMBRANE TRANSPORT
MEMBRANES
NUCLEI
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANOIDS
PHOSPHOHYDROLASES
PROTEINS
RADIOISOTOPES
RADIORECEPTOR ASSAY
RATS
RECEPTORS
RODENTS
SARCOPLASMIC RETICULUM
SOMATIC CELLS
TRACER TECHNIQUES
UPTAKE
VERTEBRATES