Plasma membranes, isolated

Primarily using isolated plasma membrane vesicles as an experimental preparation, the functional properties of Na /H exchangers have been elucidated. The important kinetic properties include (1) stoichiometry (one-for-one) (2) reversibility (3) substrate specificity (monovalent cations Na, H, Li, NH4, but not K, Rb, Cs, choline) (4) modes of operation (Na -for-H, Na -for-Na Li " -for-Na, Na -for-NH4 ) (5) existence of an internal site for allosteric activation by (6) reversible inhibition by amiloride (Af-amidino-5-amino-6-chloropyr-azine carboxamide) and its 5-amino-substituted analogs and (7) competitive nature... 

Keenan, T. W., Franke, W. W. and Kartenbeck, J. 1974A. Concanavalin A binding by isolated plasma membranes and endomembranes from liver and mammary gland. Febs. Lett. 44, 274-278. 

Attempts to produce cellulose from UDP-Glc using enzymes of isolated plasma membranes from higher plants have usually yielded the ( -1,3-linked glucan (callose) instead. This is a characteristic polysaccharide of plant wounds which, as healing occurs, is degraded and replaced by cellulose.140144 Callose... 

Mian, N., Analysis of cell-growth-phase-related variations in hyaluronate synthase activity of isolated plasma-membrane fractions of cultured human skin fibroblasts, Biochem. J., 237, 333, 1986. 

The first reported instances using isolated plasma membrane vesicles to study Na+-coupled transport were derived from brush borders of the small intestine (Murer and Hopfer, 1974 Sigrist-Nelson et al., 1975) and Ehrlich cells (Colombini and Johnstone, 1974). In rapid succession a number of other systems were established to study translocation of many solutes in many animal cell systems (Schuld-iner and Kaback, 1975 Lever, 1977 Hammerman and Sacktor, 1978 Wright et al., 1983 Saieret al., 1988 see also Table 1). 

Hopfer, U. (1978). Transport in isolated plasma membranes. Amer. J. Physiol. 234, F89-F96. 

Live and deproteinated plasma membranes of Acholeplasma laUawii were investigated by FTIR (Casal et al., 1980 Cameron et al., 1985). The temperature profiles of the gel to liquid crystalline phase transition of intact and deproteinated membranes, monitored by z/as(CD2), differ considerably. In intact membranes, the transition is broad and at temperatures within the range of the phase transition the live mycoplasma is able to keep the fluidity of its plasma membranes at a much higher level than that of the isolated plasma membrane. Native and reconstituted sarcoplasmic recticulum were investigated by Mendelsohn et al. (Mendelsohn et al., 1984). It appears that the protein Ca -ATPase interacts preferentially with the DOPC component of the membrane. A survey of these studies is available (Mantsch and McElhaney, 1991). 

Two common methods to study the role of lipid rafts in signaling pathways are detergent insolubility followed by isolation on a density gradient and cholesterol depletion. Other methodologies exist for isolating plasma membrane samples and intracellular organelles for additional characterization (47). 

Kempson SA, Ellis BG, Price RG. Changes in rat renal cortex, isolated plasma membranes, and urinary enzymes following the injection of mercuric chloride. Chem Biol Interact 1977 18 217-34. 

To examine the interaction between cortical microtubules and microfibrils more directly, we prepared an isolated plasma membrane sheet with cortical miaotubules from tobbaco cells and demonstrated that p-glucan s)mthases penetrating through the membrane move in the fluid... 

Kessler, J.A., Conn, G. and Hatchers, V.B. (1986) Isolated plasma membranes regulate neurotransmitter expression and facilitate effects of a soluble brain cholinergic factor. Proc. Natl. Acad. Sci. USA 83 3528-3532. 

Clathrin-Coated Vesicle Formation from Isolated Plasma Membranes... 

Miwako, I., Schroter, T., and Schmid, S. L. (2003). Clathrin- and dynamin-dependent coated vesicle formation from isolated plasma membranes. Traffic 4, 376-389. 

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