SEARCH · PubMed Health

Results for “Sodium Cholate”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 541 records · Page 30Linked to original sources

PubMed1982

Increase in size of sonicated phospholipid vesicles in the presence of detergents.

Triton X-100, sodium dodecylsulphate, sodium cholate, and beta-octylglucoside increase the size of sonicated, but not of unsonicated, phospholipid vesicles above the Tc gel to liquid-crystalline transition temperature. Lysophosphatidylcholine or glyceryl monooleate do not increase liposome size under these circumstances. The observed phenomenon of vesicle growth is virtually unaffected by phospholipid composition, surface potential, calcium ions, EDTA, or albumin. The presence of cholesterol makes the vesicles more susceptible to detergent-induced growth. The presence of detergents, even at concentrations much lower than required to observe any increase in vesicle size, favors the liberation of vesicle contents. These results may have implications concerning membrane fusion as well as the reconstitution of membrane proteins in the presence of detergents.

Calcium↗

PubMed1988

The prevention of experimental cholesterol gallstones by ileectomy in mice.

After a lithogenic diet containing 0.5 per cent cholesterol and 0.25 per cent sodium cholate was fed to a group of normal Crj-ICR male mice for 10 days, cholesterol gallstones developed. No formation of gallstones occurred, however, in a group of mice from which 20 cms of terminal ileum had been removed prior to the feeding of the lithogenic diet. The biliary concentrations of cholesterol, phospholipids and bile acids were markedly lower in the ileectomized mice, with the decrease in cholesterol concentration being most significant. On the other hand, fecal excretion of sterols and bile acids increased in the ileectomized mice. The pool size of bile acids increased after the feeding of the lithogenic diet, but ileectomy decreased the pool size in mice fed the ordinary or lithogenic diets. The biliary concentration of cholic acid increased after the feeding of the lithogenic diet, but decreased with ileectomy. The biliary concentration and fecal excretion of deoxycholic acid markedly increased, while those of beta-muricholic acid and its secondary bile acids, omega-muricholic acid and hyodeoxycholic acid, decreased. The increase in plasma and liver cholesterol levels after the feeding of the lithogenic diet was prevented by ileectomy. These data suggest that ileectomy prevents the formation of cholesterol gallstones after the feeding of a lithogenic diet due to a decrease in cholic acid absorption.

Animals↗

PubMed1996

Quantitative 31P nuclear magnetic resonance analysis of the phospholipids of erythrocyte membranes using detergent.

31P Nuclear magnetic resonance (NMR) spectra of human erythrocyte lysates dissolved in sodium cholate were acquired. The narrow resonances of phospholipids were mostly well resolved, allowing identification and accurate quantitative analysis of phospholipid classes of the erythrocyte membranes. The ether-linked phosphatidylethanolamine components of the erythrocyte membranes were identified, based on the removal of plasmalogens by acidolysis and of diacyl phospholipid species by degradation using phospholipase A1. It was also shown that the introduction of double bonds on the acyl chains of phosphatidylcholine shifted the 31P NMR resonances to lower frequencies. Quantitative analyses of phospholipids from the spectra were based on their apparent molar concentrations. The recoveries of phospholipids from erythrocytes were significantly higher than those using conventional extraction procedures.

Cell Extracts↗

PubMed1979

Inhibition of cholesterol synthesis in mammary tissue, lung, and kidney following cholesterol feeding in the lactating rat.

Pregnant rats were randomly allocated to one of 3 experimental dietary groups: Group 1 -- 15.5% butter, 2% cholesterol, 0.78% sodium cholate purified diet; Group 2 -- standard rat diet with the addition of 10% lard and 2% cholesterol, and Group 3 -- standard rat diet. Plasma and milk cholesterol at 10 days postpartum were significantly elevated in dams fed exogenous cholesterol. The rat of incorporation of [1-14C] acetate into digitonin-precipitable sterols of mammary tissue slices from dams in Group 1 and Group 2 was eight-fold and two-fold, respectively, less than controls. Mammary tissue cholesterol was greater in dams fed detary cholesterol. Thus, our data, for the first time, demonstrate that cholesterol synthesis in lactating rat mammary tissue is suppressed following cholesterol feeding. In a second experiment, the rate of incorporation of [1-14C] acetate into digitonin-precipitable sterols in kidney and lung tissue of Group 1 rats was suppressed; however, this response was not as marked as that observed in lactating mammary tissue. The concentration of cholesterol in kidney and lung was greater than controls. These results suggest that extrahepatic inhibition of cholesterol synthesis exists in the rat with a concomitant increase in tissue cholesterol.

Animals↗

PubMed1988

A highly active soluble diacylglycerol synthesizing system from developing rapeseed, Brassica napus L.

The subcellular distribution of the enzymes of triacylglycerol biosynthesis has been studied in developing oilseed rape. All in vitro enzymatic activities from oleoyl-CoA to triacylglycerol were sufficient to account for the known rate of oleate deposition in triacylglycerol in vivo. The enzymatic activities from oleoyl-CoA to diacylglycerol preferentially were localized in a 150,000 g supernatant fraction, while the diacylglycerol acyl-transferase mostly was associated with the microsomal (20,000 g pellet and 150,000 g pellet) and oil-body fractions. The soluble (150,000 g supernatant) fraction rapidly incorporated oleate from [1-14C]oleoyl-CoA into diacylglycerol with rates of 40 nm min-1 g-1 FW at 20 microM oleoyl-CoA. The pH optimum was 7.5-9.0, and normal saturation kinetics were seen with oleoyl-CoA; the S0.5 was about 32 microM. Exogenous acyl acceptors, such as glycerol 3-phosphate, lysophosphatidic acid and lysophosphatidyl-choline stimulated oleate incorporation into diacylglycerol. The detergents Triton X-100 and sodium cholate inhibited diacylglycerol formation at concentrations in the region of their critical micellar concentration, while n-octyl-beta, D-glyco-pyranoside had no effect, even at high concentration. The significance of these findings for the mechanism of oil-body formation in developing oilseeds is discussed.

Brassica↗

PubMed1991

Activation and solubilization by Triton X-100 of membrane-bound phospholipase D of rat brain.

In the present study, we examined the ability of detergents to stimulate and solubilize phospholipase D (PLD) of a particulate fraction of rat brain. PLD activity was assayed by measuring the [3H]choline produced from the exogenous substrate dipalmitoyl phosphatidyl[3H]choline (dipalmitoyl [3H]PC). In the absence of detergents, PLD activity was not detectable. Of the detergents examined, Triton X-100 was found to markedly enhance PLD activity, whereas other detergents including sodium deoxycholate, sodium cholate, CHAPS and Lubrol-PX caused only a small, if any increase in activity. Enhancement by Triton X-100 was maximal at 0.1-0.2% (w/v) and decreased at higher concentrations. The optimal pH was 7.1-7.3. Both Ca2+ and Mg2+ inhibited enzyme activity stimulated by Triton X-100 in a concentration-dependent manner. Triton X-100 effectively solubilized PLD from the particulate fraction of rat brain; more than 70% of the activity of the particulate fraction was extracted by 0.5-1.0% (w/v) Triton X-100. Furthermore, when the PLD activities in brains of three different species (rat, rabbit and bovine) were measured under optimal conditions, the activities were found to differ greatly. PLD activity was highest in rabbit brain, followed by rat and bovine brains; the activity in bovine brain was extremely low compared to the activities in rat and rabbit brains. We conclude that Triton X-100 is potentially useful for the purification of PLD and that rabbit and rat brains are the preferred sources.

1,2-Dipalmitoylphosphatidylcholine↗

PubMed1991

Differential effects of ursodeoxycholic acid and ursocholic acid on the formation of biliary cholesterol crystals in mice.

The preventive effect of 3 alpha, 7 beta, 12 alpha-trihydroxy-5 beta-cholanoic acid (ursocholic acid) and ursodeoxycholic acid on the formation of biliary cholesterol crystals was studied in mice. Cholesterol crystals developed with 80% incidence after feeding for five weeks a lithogenic diet containing 0.5% cholesterol and 0.25% sodium cholate. When 0.25% ursocholic acid or ursodeoxycholic acid was added to the lithogenic diet, the incidence as well as the grade (severity) of the gallstones were reduced. Plasma and liver cholesterol levels were decreased by ursodeoxycholic acid but not by ursocholic acid. Gallbladder cholesterol and phospholipid levels were decreased by both bile acids. The biliary bile acid level was decreased by ursocholic acid but not by ursodeoxycholic acid. After feeding ursocholic acid, its level in the bile was about 25% and the levels of cholic acid and beta-muricholic acid decreased. Fecal sterol excretion was not changed by ursocholic acid, but was increased by ursodeoxycholic acid. After feeding ursocholic acid, fecal excretion of deoxycholic acid, cholic acid, and ursocholic acid increased. No differences were found between mice, with or without gallstones, in plasma and liver cholesterol levels, biliary phospholipid and bile acid levels, fecal sterol and bile acid levels, and biliary and fecal bile acid composition. The results suggest that the lower incidence of crystal formation after treatment with ursocholic acid is probably by a different mechanism than with ursodeoxycholic acid. In the mouse model, ursodeoxycholic acid exerts its effect at least partially, by decreasing cholesterol absorption. Ursocholic acid is well absorbed and excreted into bile and transformed into deoxycholic acid by the intestinal microflora in mice.

Animals↗

PubMed1990

Hydrolysis of fluorescent pyrene-acyl esters by human pancreatic carboxylic ester hydrolase and bile salt-stimulated lipase.

Fluorescent esters containing pyrenedecanoic acid (P10) or pyrenebutanoic (P4) acid (P4cholesterol, P10cholesterol, P4- and P10-containing triacylglycerols) were synthesized and used as substrates for human pancreatic carboxylic ester hydrolase and bile salt-stimulated lipase from human milk. Both enzymes were purified by immunoaffinity chromatography. All fluorescent pyrene derivatives were hydrolyzed by pancreatic carboxylic ester hydrolase and bile salt-stimulated lipase, but at different rates. The hydrolytic rates of the "short" acyl esters (P4-containing esters) were higher than those of the "long" ones (P10-containing esters). Conditions were optimized for sensitivity of the assay using fluorescent cholesteryl esters. The pH optimum was 7.5-8.0. Sodium cholate exhibited a stronger activating effect than taurocholate or taurodeoxycholate (maximal activation was achieved with 5 mmol/L cholate and with a molar ratio cholesteryl ester/cholate around 1:10). Both pancreatic carboxylic ester hydrolase and bile salt-stimulated lipase from milk were strongly inhibited by the other amphiphiles tested, namely phosphatidylcholine and Triton X-100, and were inactivated by low concentrations (10 mumol/L) of the serine-reactive diethyl-paranitrophenyl phosphate (E600). Both enzymes were strongly inhibited by relatively low concentrations of plasma low density lipoproteins. These studies indicate that the fluorescent esters containing pyrene fatty acids can be used as substrates for assaying and investigating the properties of pancreatic carboxylic ester hydrolase as well as bile salt-stimulated lipase from milk.

Animals↗

PubMed1994

Biochemical and morpho-cytochemical evidence for the intestinal absorption of insulin in control and diabetic rats. Comparison between the effectiveness of duodenal and colon mucosa.

A combined biochemical and morpho-cytochemical investigation was carried out in order to assess insulin absorption by the duodenal and colon epithelium. Insulin was introduced in the lumen of the rat duodenum or colon in combination with sodium cholate and aprotinin. Blood analysis made at several time points has demonstrated a rapid increase in circulating levels of insulin followed by significant and consistent decreases in blood glucose. This indicates that biologically active insulin is absorbed by the intestinal mucosa and transferred to the circulation. Because of the initial high blood glucose levels, the lowering of the glycaemic values was more significant in diabetic animals. Also, levels of circulating insulin remained higher for longer time when the administration was performed in the colon. The integrity of the intestinal wall after insulin administration, evaluated morphologically, was retained. Application of protein A-gold immunocytochemistry has established the pathway for insulin absorption. In both duodenal and colon epithelial cells the labelling for insulin was detected in the endosomal compartment, in the Golgi apparatus and in association with the baso-lateral plasma membrane interdigitations. Some labelling was also present in the interstitial space and in capillary endothelial plasmalemmal vesicles. Insulin introduced in the lumen of the rat duodenum and colon appears thus to be rapidly internalized by the epithelial cells and transferred through a transcytotic pathway to the interstitial space from which it reaches the blood circulation. This exogenous insulin then induces significant decreases in plasma glucose levels which lasts for several hours. The results obtained support the possibility for the clinical development of an oral preparation of insulin.

Animals↗

PubMed2000

New ultradeformable drug carriers for potential transdermal application of interleukin-2 and interferon-alpha: theoretic and practical aspects.

Transfersomes (TFs) are highly deformable hydrophilic lipid vesicles that are able to penetrate the skin barrier spontaneously because of their characteristics. Transfersomes are able to transport noninvasively low- and high-molecular-weight molecules into the body. We describe the formulation and several biologic characteristics of interleukin-2 (IL-2)- and interferon-alpha (IFNalpha )-containing TFs. TFs contain natural phosphatidylcholine and sodium cholate. Recombinant human IL-2 and human hybrid IFNalpha were added to TFs and incubated for 24 hours at 4 degrees C. Immunotransfersomes were isolated from free IL-2 and IFNalpha by filtration (Centrisart, Sartorius). The biologic activity of immunotransfersomes was measured by a cytotoxic lymphoid line assay for IL-2 and by an A549-encephalomyocarditis virus assay for IFN; concentrations of proteins were determined by the enzyme-linked immunosorbent assay (ELISA). It was possible to incorporate a large amount of IL-2 and IFN in TFs (75-80%), and the incorporated IL-2, and IFN were biologically active. The increased lipid/protein ratio (90.9/1.0) led to a growing probability of association. We were thus able to show that IL-2 and IFN are trapped by transfersomes in a biologically active form and in sufficient concentrations for immunotherapy. In upcoming experiments these IL-2- and IFN-containing TFs will be used for a transdermal approach in the murine RENCA cell line model.

Administration, Cutaneous↗

PubMed2005

Molecular cloning, expression, and characterization of secretory phospholipase A2 in tobacco.

Phospholipase A2 (PLA2) activity was investigated in various tissues of tobacco (Nicotiana tabacum). PLA2 activity in the flower was 15 times higher than that in the leaf, stem, and root. PLA2 activity in the flower appears to have originated from both Ca2+-dependent and -independent PLA2. A cDNA clone for protein with homology to animal secretory PLA2 (sPLA2), denoted as Nt PLA2, was isolated from the tobacco flower. The cDNA of Nt PLA2 encoded a mature protein of 127 amino acid residues with a putative signal peptide of 30 residues. The amino acid sequence for mature Nt PLA2 contains 12 cysteines, a Ca2+ binding loop, and a catalytic domain that are commonly conserved in animal sPLA2. The Nt PLA2 mRNA was mainly expressed in the root and stem of tobacco. The recombinant Nt PLA2 was expressed as a fusion protein with thioredoxin in Escherichia coli. From the bacterial cell lysate, the fusion protein was recovered in soluble form and cleaved by Factor Xa proteinase. Then the recombinant mature Nt PLA2 was purified by ion exchange chromatography. It was discovered that the purified Nt PLA2 essentially requires Ca2+, for the enzyme activity when the activity was determined using mixed-micellar phospholipid substrates with sodium cholate. The optimal activity of Nt PLA2 was at pH 8-10 when PC was used as a substrate.

Amino Acid Sequence↗

PubMed2001

Effects of dietary maritime pine seed oil on lipoprotein metabolism and atherosclerosis development in mice expressing human apolipoprotein B.

BACKGROUND: Conifer seeds are used for food preparation in several countries. Aim of the study To assess the lipid-lowering and antiatherogenic properties of maritime pine (Pinuspinaster) seed oil. METHODS: The effects of maritime pine oil supplementation (20% w/w) for 2 weeks were compared to those of coconut and sunflower oil in mice expressing human apolipoprotein B (hApoB). Atherosclerosis lesion development was measured in hApoB mice fed 1.25% (w/w) cholesterol and 0.05% (w/w) sodium cholate and either coconut, sunflower or maritime pine oil (20% w/w) for 8 weeks. RESULTS: After 2 weeks of dietary treatment, plasma cholesterol (p < 0.0001), triglyceride (p < 0.0003), phospholipid (p < 0.0001) and apolipoprotein B (p < 0.0001) levels were lower in mice supplemented with maritime pine oil than in those treated with coconut oil. These effects were accounted for by a lowering of LDL-cholesterol, LDL-phospholipids and LDL-triglycerides, as well as a decrease in HDL-cholesterol and HDL-phospholipids. After 8 weeks of dietary treatment cholesterol and cholate, the mean area of aortic lesions was not statistically different between fat groups. CONCLUSIONS: Feeding maritime pine oil is associated with major changes of lipid and lipoprotein levels in hApoB mice. However, in the long term, maritime pine oil has no preventive effect on cholesterol-induced aortic lesion development in hApoB mice.

Animals↗

PubMed1986

Fractionation of detergent lysates of cells by ammonium sulphate-induced phase separation.

A procedure is described for fractionating detergent lysates of cells based on the ability of (NH4)2SO4 to induce phase separation of detergents such as Triton X-100, sodium deoxycholate, and sodium cholate, into detergent-rich and detergent-depleted phases. An analysis of six murine lymphocyte cell surface molecules revealed that the partitioning in Triton X-100 of each molecule was highly dependent upon the (NH4)2SO4 concentration, each antigen partitioning into the detergent-rich phase at a defined salt concentration. In contrast, none of the six molecules appeared in the detergent-rich phase of a Triton X-114 phase separation, even though two of the molecules, namely Ly-2/3 and L3T4, are well-characterized integral membrane proteins. It was also observed that (NH4)2SO4 resulted in the partitioning of many nonmembrane proteins into the detergent-rich phase, indicating that the procedure can be used to fractionate all cellular proteins. By judicious choice of (NH4)2SO4 concentrations, precipitation of cellular proteins at two different (NH4)2SO4 concentrations, and combining the method with subcellular fractionation prior to detergent solubilization, substantial enrichment and concentration of particular cellular proteins could be achieved.

Ammonium Sulfate↗

PubMed1983

Solubilization and partial purification of dihydroxyacetone-phosphate acyltransferase from guinea pig liver.

Dihydroxyacetone-phosphate:acyl coenzyme A acyltransferase (EC 2.3.1.42) was solubilized and partially purified from guinea pig liver crude peroxisomal fraction. The peroxisomal membrane was isolated after osmotic shock treatment and the bound dihydroxyacetone-phosphate acyltransferase was solubilized by treatment with a mixture of KCl-sodium cholate. The solubilized enzyme was partially purified by ammonium sulfate fractionation followed by Sepharose 6B gel filtration. The enzyme was purified 1200-fold relative to the guinea pig liver homogenate and 80- to 100-fold from the crude peroxisomal fraction, with an overall yield of 25-30% from peroxisomes. The partially purified enzyme was stimulated two- to fourfold by Asolectin (a soybean phospholipid preparation), and also by individual classes of phospholipid such as phosphatidylcholine and phosphatidylglycerol. The kinetic properties of the enzyme showed that in the absence of Asolectin there was a discontinuity in the reciprocal plot indicating two different apparent Km values (0.1 and 0.5 mM) for dihydroxyacetone phosphate. The Vmax was 333 nmol/min/mg protein. In the presence of Asolectin the reciprocal plot was linear, with a Km = 0.1 mM and no change in Vmax. The enzyme catalyzed both an exchange of acyl groups between dihydroxyacetone phosphate and palmitoyl dihydroxyacetone phosphate in the presence of CoA and the formation of palmitoyl [3H]coenzyme A from palmitoyl dihydroxyacetone phosphate and [3H]coenzyme A, indicating that the reaction is reversible. The partially purified enzyme preparation had negligible glycerol-3-phosphate acyltransferase (EC 2.3.1.15) activity.

Acyltransferases↗

PubMed1984

Solubilization and characterization of vitamin K epoxide reductase from normal and warfarin-resistant rat liver microsomes.

Two procedures have been developed for the solubilization of vitamin K epoxide reductase from rat liver microsomal membranes using the detergent Deriphat 160 at pH 10.8. The methods are applicable to both normal and Warfarin-resistant-strain rat liver microsomes and yield material suitable for further purification. The preparations retain dithiothreitol-dependent vitamin K quinone reductase activity as well as vitamin K epoxide reductase and are free of vitamin K-dependent carboxylase and epoxidase activities. Optimal epoxide reductase activity is obtained at 0.1 M KCl and pH 9 in the presence of sodium cholate. Artifactual formation of vitamin K metabolites was eliminated through the use of mercuric chloride to remove excess dithiothreitol prior to extraction and metabolite assay. Using the solubilized enzyme, valid initial velocities were measured, and reproducible kinetic data was obtained. The substrate initial velocity patterns were determined and are consistent with a ping-pong kinetic mechanism. The kinetic parameters obtained are a function of the cholate concentration, but do not vary drastically from those obtained using intact microsomal membranes. At 0.8% cholate, the enzymes solubilized from normal Warfarin-sensitive- and Warfarin-resistant-strain rat livers exhibit respective values of Vmax = 3 and 0.75 nmol/min/g liver; Km for vitamin K epoxide = 9 and 4 microM; and Km for dithiothreitol of 0.6 and 0.16 mM.

Animals↗

PubMed1984

Calmodulin and parvalbumin: activators of human liver glucocerebrosidase.

Lysosomal glucocerebrosidase of human tissues is reversibly inactivated by extraction with sodium cholate and n-butanol. Enzyme activity can be restored in the glucocerebrosidase assay by the incorporation of small amounts of phosphatidylserine (1 micrograms/assay) and a heat-stable factor obtained from the spleen of patients with Gaucher's disease. In the present report, we show that two heat-stable, low-molecular-weight, acidic, calcium-binding proteins, namely calmodulin and parvalbumin, are relatively potent activators of human liver glucocerebrosidase. A third structurally related, calcium-binding protein, troponin-C, does not stimulate glucocerebrosidase significantly. Removal of calcium from these proteins by treatment with 5 mM ethylene glycol bis(beta-aminoethylether)-N,N'-tetraacetic acid greatly decreases the quantity of material needed to stimulate enzyme activity. Parvalbumin stimulation of glucocerebrosidase activity is dependent on the presence of phosphatidylserine whereas the ability of calmodulin to activate the enzyme is not dependent on the acidic phospholipid. In terms of the level of glucocerebrosidase activity they support and under optimal conditions, parvalbumin and calmodulin are about 50 and 30%, respectively, as effective as the heat-stable factor from Gaucher spleen. On the other hand, on a molar basis, it takes about 35 times more parvalbumin than calmodulin to achieve maximum stimulation of glucocerebrosidase activity.

Calmodulin↗

PubMed1985

Comparison of N-acyl phosphatidylethanolamines with different N-acyl groups as activators of glucocerebrosidase in various forms of Gaucher's disease.

The acidic phospholipid requirement of the predominant particulate beta-glucosidase of mammalian spleen and liver was investigated using a series of N-acyl derivatives of dioleoyl phosphatidylethanolamine (PE). The PE, a neutral phospholipid, was converted to an acidic lipid, (N-acyl)-phosphatidylethanolamine (NAPE) by acylation of the amino group with different fatty acyl chains. Lysosomal beta-glucosidases from rat liver and spleens of controls and patients with various types of Gaucher's disease were solubilized and delipidated by extraction with sodium cholate and 1-butanol. All members of the NAPE series tested were effective activators of the delipidated rat liver beta-glucosidase, and the stimulatory power of the NAPE family increased with increasing chain length of the fatty acid substitution. In contrast, dioleoyl-PE had no effect on beta-glucosidase activity. A heat-stable factor (HSF) purified from the spleen of a patient with Gaucher's disease significantly increased the sensitivity of the rat liver beta-glucosidase to all of the NAPE derivatives. The maximum stimulation achieved in the presence of HSF was independent of N-acyl chain length. Compared to the potent activator, phosphatidylserine (PS), (N-acetyl)-PE and (N-linoleoyl)-PE were half as effective as activators of beta-glucosidase from control human spleen. PS stimulated the beta-glucosidase of type 1 nonneurologic Gaucher's disease, but none of the NAPE compounds activated it. Neither PS nor any of the (N-acyl)-PE compounds could activate a delipidated preparation of beta-glucosidase obtained from the spleen of a neurologic case. These results indicate that although the presence of a net negative charge on a phospholipid confers upon it an ability to reconstitute beta-glucosidase activity to the normal, nonmutant enzyme, it is insufficient to permit differentiation of the various types of Gaucher's disease.

Acylation↗

PubMed1988

Reconstitution of fusogenic Sendai virus envelopes by the use of the detergent chaps.

Sendai virus envelopes have been a useful tool in studying the mechanism of membrane-membrane fusion and have served as a vehicle for introducing foreign molecules (e.g., membrane proteins) into recipient cells. Reconstituted Sendai virus envelopes are routinely obtained following solubilization of virus particles with Triton X-100. This detergent has a low critical micellar concentration which precludes it from being the best detergent of choice in reconstitution studies. Nevertheless, it has remained in use since other detergents such as sodium deoxycholate and sodium cholate rendered the resultant vesicles inactive. Triton X-100 may be suboptimal for studies of some proteins that need be coreconstituted with the viral envelopes. Thus, alternative advantageous detergents, which retain the envelope fusogenic activity, have been sought. In this study we show that the synthetic detergent 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate (Chaps) effectively solubilizes the Sendai virions, and that the vesicles formed by simple reconstitution protocols appear structurally and biochemically similar to those obtained with Triton X-100. The resultant vesicles retain functional integrity as assessed in both fusion and hemolysis assays. This protocol seems to be useful in sendai envelope-mediated reimplantation of Fc epsilon receptors into the plasma membranes of rat basophilic leukemia cells.

Cell Membrane↗