Isolation and characterization of plasma membranes from bovine carotid arteries

1986 ◽  
Vol 250 (1) ◽  
pp. C65-C75 ◽  
Author(s):  
R. V. Sharma ◽  
R. C. Bhalla
Keyword(s):  
Plasma Membrane ◽  
Cytochrome C ◽  
Membrane Fraction ◽  
Plasma Membranes ◽  
Carotid Arteries ◽  
Membrane Vesicles ◽  
Plasma Membrane Vesicles ◽  
Cytochrome C Reductase ◽  
Plasma Membrane Fraction

A plasma membrane fraction from bovine carotid arteries has been isolated by extraction of a crude microsomal fraction with a low-ionic-strength buffer containing ATP and Ca2+. This step was followed by sucrose-density-gradient centrifugation in the presence of 0.6 M KCl. The plasma membrane vesicles were enriched 60- to 80-fold in Na+-K+-adenosinetriphosphatase, 5'-nucleotidase, and phosphodiesterase I activities. The final yields of these marker enzymes were 12-18% of the total activities in the postnuclear supernatant, and the protein yield was 100-120 micrograms/g wet wt of carotid arteries. Contamination of the plasma membrane fraction by mitochondria and sarcoplasmic reticulum was low as judged by low activities of succinate--cytochrome-c reductase and NADPH--cytochrome-c reductase, respectively. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoprecipitation with smooth muscle-specific actin antibodies showed that the plasma membrane fraction was substantially free from myosin and actin contamination. The plasma membrane vesicles accumulated Ca2+ in the presence of ATP, and the accumulation was increased by calmodulin. Ca2+ accumulated in the presence or absence of calmodulin could be released almost completely from the vesicles by the addition of the Ca2+ ionophore A23187 but not by ethyleneglycol-bis(beta-aminoethylether)-N,N'-tetraacetic acid, indicating that Ca2+ uptake in the presence of ATP is intravesicular. The effects of phosphate and oxalate on Ca2+ uptake in the plasma membranes were different from one another. Phosphate increased Ca2+ uptake in a concentration- and time-dependent manner, and the increase in Ca2+ uptake could be observed as early as 1 min. On the other hand, oxalate at concentrations up to 5 mM did not increase Ca2+ uptake significantly during the 30-min incubation. These plasma membranes can prove useful for the study of ion transport across plasma membranes, hormone binding, characterization of calcium channels, and preparation of antibodies against plasma membrane proteins.

scholarly journals PREPARATION AND CHARACTERIZATION OF A PLASMA MEMBRANE FRACTION FROM ISOLATED FAT CELLS

1970 ◽  
Vol 44 (2) ◽  
pp. 417-432 ◽  
Author(s):  
Daniel W. McKeel ◽  
Leonard Jarett
Keyword(s):  
Plasma Membrane ◽  
Cytochrome C ◽  
Membrane Fraction ◽  
Plasma Membranes ◽  
Reductase Activity ◽  
Fat Cells ◽  
Isolated Fat Cells ◽  
Adenyl Cyclase Activity ◽  
Cytochrome C Reductase ◽  
Plasma Membrane Fraction

A rapid method of preparing plasma membranes from isolated fat cells is described. After homogenization of the cells, various fractions were isolated by differential centrifugation and linear gradients. Ficoll gradients were preferred because total preparation time was under 3 hr. The density of the plasma membranes was 1.14 in sucrose. The plasma membrane fraction was virtually uncontaminated by nuclei but contained 10% of the mitochondrial succinic dehydrogenase activity and 25–30% of the RNA and reduced nicotinamide adenine dinucleotide cytochrome c reductase activity of the microsomal fraction. Part of the RNA and NADH-cytochrome c reductase activity was believed to be native to the plasma membrane or to the attached endoplasmic reticulum membranes demonstrated by electron microscopy. The adenyl cyclase activity of the plasma membrane fraction was five times that of Rodbell's "ghost" preparation and retained sensitivity to epinephrine. The plasma membrane ATPase activity was five times that of the homogenate and microsomal fractions. Electron microscopic evidence suggested contamination of the plasma membrane fraction by other subcellular components to be less than the biochemical data indicated.

scholarly journals ISOLATION AND PROPERTIES OF THE PLASMA MEMBRANE OF KB CELLS

1973 ◽  
Vol 59 (2) ◽  
pp. 421-435 ◽  
Author(s):  
F. C. Charalampous ◽  
N. K. Gonatas ◽  
A. D. Melbourne
Keyword(s):  
Plasma Membrane ◽  
Cytochrome C ◽  
Membrane Fraction ◽  
Plasma Membranes ◽  
Latex Bead ◽  
Kb Cells ◽  
Cytochrome C Reductase ◽  
Plasma Membrane Fraction ◽  
Morphological Criteria ◽  
Discontinuous Sucrose Gradient

Plasma membranes from KB cells were isolated by the method of latex bead ingestion and were compared with those obtained by the ZnCl2 method. Optimal conditions for bead uptake and the isolation procedure employing discontinuous sucrose gradient centrifugation are described. All steps of preparative procedure were monitored by electron microscopy and specific enzyme activities. The plasma membrane fraction obtained by both methods is characterized by the presence of the Na+ + K+-activated ATPase and 5'-nucleotidase, and contains NADPH-cytochrome c reductase and cytochrome b5. The latter two enzymes are also present in lower concentrations in the microsomal fraction. Unlike microsomes which are devoid of the Na+ + K+-activated ATPase and which contain only traces of 5'-nucleotidase activity, the plasma membrane fraction contains only trace amounts of the rotenone-insensitive NADH-cytochrome c reductase but no cytochrome P-450, both of which are mainly microsomal components. Morphologically the plasma membrane fraction isolated by the latex bead method is composed of vesicles of 0.1–0.3 µm in diameter. On the basis of the biochemical and morphological criteria presented, it is concluded that the plasma membrane fraction isolated by the above methods are of high degree of purity.

Characteristics of calcium transport and binding by rat myometrium plasma membrane subfractions

1980 ◽  
Vol 239 (3) ◽  
pp. C66-C74 ◽  
Author(s):  
A. K. Grover ◽  
C. Y. Kwan ◽  
J. Crankshaw ◽  
D. J. Crankshaw ◽  
R. E. Garfield ◽  
...  
Keyword(s):  
Plasma Membrane ◽  
Cytochrome C ◽  
Buoyant Density ◽  
Membrane Vesicles ◽  
Ionophore A23187 ◽  
Plasma Membrane Vesicles ◽  
Thin Sections ◽  
Cytochrome C Reductase ◽  
Ca Uptake ◽  
High Concentrations

A gradient has been designed to yield two subfractions of plasma membrane vesicles from rat myometrium, a low buoyant density (8-24% sucrose) fraction N1 richer in 5'-nucleotidase and a higher buoyant density (24-30% sucrose) fraction N2, instead of a previously described fraction F1. Both N1 and N2 had very low activities of NADPH-cytochrome c reductase and succinate-cytochrome c reductase. Electron micrographs of thin sections of N1 showed clear vesicles, whereas N2 consisted of vesicles with electron-dense bodies attached to them. These plasma membrane vesicles can actively take up Ca. The active uptake of Ca was potentiated by oxalate and phosphate and abolished by the Ca ionophore A23187. Dilution of actively loaded vesicles in isotonic media containing EGTA led to loss of a small proportion of the stored Ca instantaneously and the remainder more slowly in a biphasic manner. Dilution in hypotonic media with EGTA led to a release of a much larger proportion of the accumulated Ca. A23187 at high concentrations (10 microM) caused a release of all the sequestered Ca whether the active Ca uptake had been carried out in the presence or in the absence of oxalate. A23187, 0.5 microM, released all the sequestered Ca from the vesicles that were actively loaded in the absence of oxalate, but only 37% when the vesicles were actively loaded with Ca in the presence of oxalate. Comparison of the composite plasma membrane fraction F1 (8-30% sucrose) and the subfractions N1 and N2 showed that they had different capacities for Ca uptake in the presence and absence of ATP. An attempt has been made to analyze the active Ca-uptake data in terms of various Ca pools.

Characterization of Mg-ATP-dependent Ca2+ transport in cat pancreatic microsomes

1983 ◽  
Vol 244 (5) ◽  
pp. G480-G490 ◽  
Author(s):  
A. Kribben ◽  
T. Tyrakowski ◽  
I. Schulz
Keyword(s):  
Plasma Membrane ◽  
Cytochrome C ◽  
Atpase Activity ◽  
Plasma Membranes ◽  
Specific Activity ◽  
Tissue Homogenate ◽  
Ionophore A23187 ◽  
Plasma Membrane Vesicles ◽  
Cytochrome C Reductase ◽  
Nadh Cytochrome

Mg-ATP-dependent 45Ca2+ uptake and Ca2+-ATPase activity have been examined in isolated microsomes obtained by differential centrifugation and in purified subcellular fractions obtained by Ficoll-sucrose density centrifugation in the presence of mitochondrial inhibitors. Mg-ATP-dependent 45Ca2+ uptake increased with increasing EGTA-buffered free [Ca2+], reaching a maximum of 2 nmol 45Ca2+ X 15 min-1 X mg prot-1 at 2 mumol/1 [Ca2+] in the incubation medium. Half-maximal 45Ca2+ uptake was at approximately 0.2 mumol/1 [Ca2+]. Maximal Ca2+ -Mg2+ -ATPase activity was 130 nmol X 15 min-1 X mg prot-1 at 2 mumol/l [Ca2+], with an apparent Km of approximately 0.3 mumol/l [Ca2+]. The Ca2+ ionophore A23187 (10(-6) mol/l), the mercurial compounds mersalyl (10(-5) mol/l) and CH3ClHg (10(-3) mol/l), as well as La3+ (10(-4) mol/l), vanadate (10(-4) mol/l), and saponin (50 micrograms/mg prot), abolished Mg-ATP-promoted 45Ca2+ uptake. In the absence of Mg2+, ATP did not provoke 45Ca2+ uptake. Using the purified smooth membrane fraction (F1) from the Ficoll-sucrose density gradient (enrichment of Na+-K+-ATPase specific activity by ninefold and of NADH-cytochrome c reductase by threefold as compared with total tissue homogenate), Mg-ATP-dependent 45Ca2+ uptake correlated better with Na+-K+-ATPase (r = 0.97) than with the smooth endoplasmic marker NADH-cytochrome c reductase (r = 0.52). No correlation was found with RNA, the marker for rough endoplasmic reticulum. We conclude that pancreatic plasma membranes contain a Ca2+-Mg2+-ATPase that represents the Ca2+ extrusion system from acinar cells. It is also possible that vesicular membrane structures associated with the plasma membrane, or endocytotic plasma membrane vesicles, take up Ca2+ and represent an intracellular Ca2+ pool.

scholarly journals Isolation of a plasma-membrane fraction from gastric smooth muscle. Comparison of the calcium uptake with that in endoplasmic reticulum

1983 ◽  
Vol 210 (2) ◽  
pp. 315-322 ◽  
Author(s):  
L Raeymaekers ◽  
F Wuytack ◽  
J Eggermont ◽  
G De Schutter ◽  
R Casteels
Keyword(s):  
Endoplasmic Reticulum ◽  
Smooth Muscle ◽  
Plasma Membrane ◽  
Membrane Fraction ◽  
Microsomal Fraction ◽  
Membrane Vesicles ◽  
Cholesterol Content ◽  
Sucrose Density Gradient ◽  
Plasma Membrane Vesicles ◽  
Plasma Membrane Fraction

1. A plasma-membrane fraction was isolated from the smooth muscle of the pig stomach by using differential and sucrose-density-gradient centrifugations. When the centrifugation was carried out after preloading the crude microsomal fraction with Ca2+ in the presence of oxalate, the contamination of the plasma-membrane fraction by endoplasmic reticulum was decreased and a fraction enriched in endoplasmic reticulum vesicles filled with calcium oxalate crystals was obtained. 2. The plasmalemmal and endoplasmic-reticulum membranes could be distinguished by differences in the activity of marker enzymes and in the cholesterol content and by their different permeability to oxalate and phosphate. Oxalate and phosphate stimulated the Ca2+ uptake in the endoplasmic reticulum much more than in the plasmalemmal vesicles. In the plasma-membrane vesicles 40 mM-phosphate was more effective for stimulating the Ca2+ uptake than was 5 mM-oxalate, but the reverse was seen in the endoplasmic reticulum. 3. The high cholesterol/phospholipid ratio of the crude microsomal fraction are of the majority of the vesicles present in the crude microsomal fraction are of plasmalemmal origin. 4. The Ca2+ pump of the plasmalemmal and endoplasmic-reticulum vesicles could be differentiated by their different sensitivities to calmodulin. However, the two Ca2+-transport ATPases did not differ by their sensitivity to vanadate nor by the energization of the Ca2+ transport by different nucleoside triphosphates.

scholarly journals Maltose/proton co-transport in Saccharomyces cerevisiae. Comparative study with cells and plasma membrane vesicles

1992 ◽  
Vol 284 (2) ◽  
pp. 441-445 ◽  
Author(s):  
C C M Van Leeuwen ◽  
R A Weusthuis ◽  
E Postma ◽  
P J A Van den Broek ◽  
J P Van Dijken
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Plasma Membrane ◽  
Cytochrome C ◽  
Cytochrome C Oxidase ◽  
Plasma Membranes ◽  
Membrane Vesicles ◽  
Proton Motive Force ◽  
Plasma Membrane Vesicles ◽  
Intact Cells ◽  
Maltose Transport

Maltose/proton co-transport was studied in intact cells and in plasma membrane vesicles of the yeast Saccharomyces cerevisiae. In order to determine uphill transport in vesicles, plasma membranes were fused with proteoliposomes containing cytochrome c oxidase as a proton-motive force-generating system. Maltose accumulation, dependent on the electrical and pH gradients, was observed. The initial uptake velocity and accumulation ratio in vesicles proved to be dependent on the external pH. Moreover, kinetic analysis of maltose transport showed that Vmax. values greatly decreased with increasing pH, whereas the Km remained virtually constant. These observations were in good agreement with results obtained with intact cells, and suggest that proton binding to the carrier proceeds with an apparent pK of 5.7. The observation with intact cells that maltose is co-transported with protons in a one-to-one stoichiometry was ascertained in the vesicle system by measuring the balance between proton-motive force and the chemical maltose gradient. These results show that maltose transport in vesicles prepared by fusion of plasma membranes with cytochrome c oxidase proteoliposomes behaves in a similar way as in intact cells. It is therefore concluded that this vesicle model system offers a wide range of new possibilities for the study of maltose/proton co-transport in more detail.

Pore-Spanning Plasma Membranes Derived from Giant Plasma Membrane Vesicles

2021 ◽  
Author(s):  
Nikolas K. Teiwes ◽  
Ingo Mey ◽  
Phila C. Baumann ◽  
Lena Strieker ◽  
Ulla Unkelbach ◽  
...  
Keyword(s):  
Plasma Membrane ◽  
Plasma Membranes ◽  
Membrane Vesicles ◽  
Plasma Membrane Vesicles

scholarly journals Development of an aqueous-space mixing assay for fusion of granules and plasma membranes from human neutrophils

1996 ◽  
Vol 314 (2) ◽  
pp. 469-475 ◽  
Author(s):  
R. Alexander BLACKWOOD ◽  
James E. SMOLEN ◽  
Ronald J. HESSLER ◽  
Donna M. HARSH ◽  
Amy TRANSUE
Keyword(s):  
Plasma Membrane ◽  
Plasma Membranes ◽  
Membrane Vesicles ◽  
Phospholipid Vesicle ◽  
Human Neutrophils ◽  
Plasma Membrane Vesicles ◽  
Fluorescent Marker ◽  
Whole Cells ◽  
Specific Granules ◽  
Neutrophil Degranulation

Several models have been developed to study neutrophil degranulation. At the most basic level, phospholipid vesicles have been used to investigate the lipid interactions occurring during membrane fusion. The two major forms of assays used to measure phospholipid vesicle fusion are based either on the dilution of tagged phospholipids within the membrane of the two fusing partners or the mixing of the aqueous contents of the vesicles. Although problems exist with both methods, the latter is considered to be more accurate and representative of true fusion. Using 8-aminonaphthalene-1,3,6-trisulphonic acid (ANTS) as a fluorescent marker, we have taken advantage of the quenching properties of p-xylenebispyridinium bromide (‘DPX’) to develop a simple aqueous-space mixing assay that can be used with any sealed vesicle. We compared our new assay with more conventional assays using liposomes composed of phosphatidic acid (PA) and phosphatidylethanolamine (PE), obtaining comparable results with respect to Ca2+-dependent fusion. We extended our studies to measure the fusion of neutrophil plasma-membrane vesicles as well as azurophil and specific granules with PA/PE (1:3) liposomes. Both specific granules and plasma-membrane vesicles fused with PA/PE liposomes at [Ca2+] as low as 500 μM, while azurophil granules showed no fusion at [Ca2+] as high as 12 mM. These differences in the ability of Ca2+ to induce fusion may be related to differences observed in whole cells with respect to secretion.

Sign in / Sign up

Export Citation Format

Share Document