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S Kurioka

Publications and source records attributed to S Kurioka.

18 recordsLinked to original sources
PubMed1992

Analysis of Con A-binding glycoproteins in synaptosomal membranes.

Concanavalin A (Con A)-binding proteins obtained from solubilized synaptosomal membranes of bovine brain were analyzed by two-dimensional electrophoresis (2DE), and were identified by peroxidase conjugated Con A (Con A-peroxidase staining), after transfer from 2DE gel to nitrocellulose paper. The Con A-binding proteins were resolved up to 40 spots, ranging in isoelectric points (pI) from 4.5 to 8.0 and molecular weight (MW) from 10 kDa to 120 kDa. Most of the Con A-binding proteins were streaked across a pH gradient and/or exhibited as multiple spots, indicating broad charge and molecular weight heterogeneity. The presence of protein groups that showed high affinities for Con A were revealed. Most interesting group (named GP51), which consisted of seven spots separated horizontally in charge heterogeneity (pI5.85-7.5) with MW 51 kDa, was characterized by its binding to an immobilized protein A gel. This implies that GP51 is related to immunoglobulins and/or GP51 may be a new member of the immunoglobulin supergene family.

Animals↗
PubMed1990

Analysis and separation of synaptosomal membrane proteins.

Synaptosomal membrane proteins solubilized with 8% CHAPS-8 M urea were analyzed with two-dimensional electrophoresis (2DE). The membrane proteins were resolved up to 250 spots on a 2DE map, ranging in isoelectric points (pI) from 3.5 to 10.0 and molecular weights (MW) from 10 kDa to 200 kDa. Comparison of the mapped proteins of synaptosomal membranes with those of myelin and mitochondrial membranes revealed that synaptosomal membrane proteins were characteristic in the area of pI from 4.0 to 7.5 and MW from 20 kDa to 130 kDa, and that at least 30 spots were synaptosomal membrane-specific proteins. Most of these 30 proteins have not been previously described, named, and characterized. Serial numbers (from SY1 to SY30) were assigned to the proteins on the map in order to investigate them systematically. A preliminary attempt to separate synaptosomal membrane proteins was carried out using a reversed-phase HPLC system. Several proteins could either be isolated or enriched. SY10 (pI 4.6; MW 56 kDa) was one of these proteins, and was of particular interest for its unusual behavior on the reversed-phase column, and for its binding to an immobilized protein A-gel.

Animals↗
PubMed1985

Inhibitory effect of cephalosporins on gamma-aminobutyric acid receptor binding in rat synaptic membranes.

Cephalosporins inhibited gamma-aminobutyric acid receptor binding in a concentration-dependent manner in vitro. Scatchard analysis revealed that cefazolin decreased the binding capacity but did not change the affinity of the receptor. It is suggested that this inhibition of gamma-aminobutyric acid receptor binding may be involved in the induction of convulsions by cephalosporins.

Animals↗
PubMed1983

4-Aminobutyraldehyde as a substance convertible in vivo to GABA.

[2,3-3H]4-Aminobutyraldehyde ([3H]ABAL) was injected subcutaneously into mice, which were sacrificed at various intervals following injection. [3H] gamma-Aminobutyric acid ([3H]GABA) synthesized in vivo from [3H]ABAL was extracted from the brains, separated, and quantitated. The results showed that in the brain, injected [3HABAL was rapidly transformed into [3H]GABA. [3H]ABAL may penetrate the blood--brain barrier into the central nervous system and then be oxidized to [3H]GABA.

Aldehydes↗
PubMed1982

4-Aminobutyraldehyde dehydrogenase activity in rat brain.

An enzyme with NAD+-dependent 4-aminobutyraldehyde dehydrogenase activity was purified about 360-fold from rat brain extract. AMP-Sepharose chromatography was effective in separating the enzyme from other NAD+-dependent aldehyde dehydrogenases included in the extract. The KmS for the substrates NAD+ and 4-aminobutyraldehyde were 4.8 x 10(-4) and 8.3 x 10(-5) M, respectively. The pH optimum for the enzyme was about 8.0. The ratio of activities toward 4-aminobutyraldehyde, propionaldehyde, succinate semialdehyde, and benzaldehyde was 1.00:0.17:0.24:0.09:0.03 when the activity toward 4-aminobutyraldehyde was set equal to 1.00. The enzyme activity in subcellular fractions of rat brain was localized in cytosol.

Aldehyde Oxidoreductases↗
PubMed1981

Characterization of gamma-aminobutyric acid binding sites on crude synaptic membranes.

[3H]GABA binding to crude synaptic membranes of rat brain was studied in an attempt to identify GABA binding to its synaptic receptor in the presence of Na+. Membrane vesicles prepared from crude synaptic membrane fractions were useful as a tool to differentiate synaptic GABA receptors from GABA uptake sites. The crude synaptic membranes treated with Triton X-100 [membranes (TX)] involved two classes of GABA binding sites (KD = 38.7 and 78.0 nM) in the absence of Na+, but the high-affinity sites disappeared in the presence of Na+ and a single class of GABA binding sites (KD = 75.0 nM) was detected. The failure to detect an active uptake of [3H]GABA into the vesicles prepared from membranes (TX) suggests that the [3H]GABA binding in the presence of Na+ was related to synaptic GABA receptors. It is probable that Na+ could mask the presence of the high-affinity class of GABA receptor.

Animals↗
PubMed1981

Effects of sodium and bicarbonate ions on gamma-aminobutyric acid receptor binding in synaptic membranes of rat brain.

Crude synaptic membranes treated with Triton X-100 (TX) bound gamma-aminobutyric acid (GABA) to two classes of receptor site in Na+-free 10 mM-Tris-sulfate buffer (pH 7.4), but to only a single class of receptor site in 10 mM Tris-sulfate buffer (pH 7.4), containing 150 mM-NaCl. The high-affinity receptor site in TX membranes was specifically masked in the presence of Na+. However, TX membranes incubated in Krebs-Ringer bicarbonate solution (pH 7.4) bound GABA to two classes of receptor site despite the presence of Na+. It was found that addition of bicarbonate ions to the Na+-containing 10 mM-Tris-sulfate buffer (pH 7.4) could restore that high-affinity class of GABA receptors, rendering both classes detectable. This finding suggests that both Na+ and HCO-3 may have a regulatory function on GABA binding to the receptor.

Animals↗
PubMed1976

Dispersion of fibrin using cationic detergent.

By treating fibrin with cationic detergent in a medium containing 5M urea, a fibrincationic detergent complex was formed. The complex was soluble in distilled water, and was observed to be in a dispersed state by electron microscopy. The complex was precipitated and resolubilized in the presence of salt. This behavior of the complex was due to adsorption of the salt anions onto the complex. When an aqueous solution of the complex was incubated with fresh serum, the complex soon aggregated and then was converted into a firm clot which was not soluble in distilled water.

Blood↗
PubMed1975

Interaction of fibrinogen with detergent.

Both cationic and anionic detergents were found to precipitate fibrinogen by forming fibrinogen-detergent complexes. These complexes were soluble in distilled water, but the aqueous solutions were very unstable and the complexes precipitated in the presence of salt. In the interaction of fibrinogen with the cationic detergent, stearyltrimethyl-ammonium chloride, approximately 160 molecules of detergent were found to bind to one molecule of fibrinogen. In distilled water, the fibrinogen-stearyltrimethylammonium complex (FG-STA(Cl)) remained soluble in the presence of thrombin [ED 3.4.21.5] although the same peptides were released as those released from fibrinogen. Precipitation of FG-STA(Cl) by salt was found to be closely related to adsorption of the anion of the salt by the complex. Futher addition of salt resulted in solubilization of the precipitate, and the solubilization was also due to further adsorption of the anion onto the precipitate.

Animals↗
PubMed1975

Purification of fibrinogen using cationic detergent.

Stearyltrimethylammonium chloride was used to isolate human fibrinogen, and purified protein was obtained by removing the detergent bound to it. Medium consisting of 0.015--0.03 mM fibrinogen-detergent complex, 0.85 M NaCl, 0.03 M sodium caprylate, and 30 per cent ethanol was found to be effective for renaturation of fibrinogen from the complex. The purified fibrinogen did not form any fibrils on incubation for 15 days with Ca-2+ at pH 7.2, and 37 degrees. The clottability of the purified fibrinogen was over 99 per cent. Immunochemical studies showed that the purified fibrinogen produced one precipitation line with a mixture of anti-human fibrinogen and anti-human serum. Although highly purified, the fibrinogen preparation still contained a trace of plasminogen.

Calcium↗
PubMed1975

Chemical modification of carboxyl groups of fibrinogen and its effect on the binding of cationic detergent.

Carboxyl groups of native human fibrinogen were modified with glycine methyl ester and 1-ethyl-3(3-dimethylaminopropyl)carbodiimide. It seemed likely that the modification occurred stepwise. Approximately 26% of the carboxyl groups of fibrinogen was modified finally. The modified fibrinogen had no interaction with cationic detergent, and did not form any complex with the detergent. In dilute acid, fibrinogen was observed to show only a slight interaction with cationic detergent. It is probable that the exposed and ionized carboxyl groups are essential for the formation of a complex between fibrinogen and cationic detergent.

Carbodiimides↗
PubMed1967

Improved assay method for phospholipase C.

A lecithin sol dispersed with deoxycholate was found to be attacked by phospholipase C in the presence of calcium ion more rapidly than were any other lecithin sols. The inorganic phosphate could be released quantitatively from the acid soluble phosphate liberated from lecithin by an excess amount of alkaline phosphatase present in phospholipase C reaction mixture. A simple and accurate assay method for phospholipase C was developed with the sol and the alkaline phosphatase.

Alkaline Phosphatase↗
PubMedDate not supplied

Detection of abnormal haemoglobin by capillary electrophoresis and structural identification.

Haemoglobin obtained from a male adult Ghanian with retinopathy, which was probably caused by haemoglobinopathy was analysed by capillary electrophoresis (CE) for clinical diagnosis. Two major peaks, which were in the ratio of nearly one, were detected. The elution times of these peaks (HbXI and HbXII) were faster than that of normal haemoglobin (HbA). The existence of two different abnormal types of haemoglobin was clear in the patient blood. The following sequence analysis revealed that the first peak (HbXI) was HbC and the second (HbXII) was HbS on the electropherogram, and that the patient was a heterozygote of HbS and HbC (HbSC disease). One of the diagnostic processes in a haemoglobin disease was shown by the combined use of CE, HPLC and a protein sequencer.

Adult↗