
	Where results make sense

Topic: Bilayer

In the News (Thu 31 Dec 09)

Northern Trust

Marvin Harrison

Peter Chernin

Gary Locke

Match Play

Penelope Cruz

Mickey Rourke

AR Rahman

Danny Boyle

Hugh Jackman

	Encyclopedia: Lipid bilayer
		In biology and chemistry, a lipid bilayer is a membrane or zone of a membrane composed of lipid molecules (usually phospholipids).
		The lipid bilayer is the foundation of all biological membranes, including cell membranes, and is a prerequisite of cell-based life.
		The bilayer is composed of two opposing layers of lipid molecules arranged so that their hydrocarbon tails face one another to form the oily bilayer core, while their electrically charged or polar heads face the watery or "aqueous" solutions on either side of the membrane.
	www.nationmaster.com /encyclopedia/Lipid-bilayer (657 words)

	Lipid bilayer - Open Encyclopedia (Site not responding. Last check: 2007-10-29)
		In biology and chemistry, a lipid bilayer is a membrane or zone of membrane composed only of lipid.
		Lipid bilayer is the foundation of all biological membranes, and is a prerequisite of cell-based life.
		Because of the oily core, a pure lipid bilayer is permeable to small hydrophobic solutes but has an only very low permeability barrier to inorganic ions and other hydrophilic molecules.
	open-encyclopedia.com /Phospholipid_bilayer (138 words)

	Bilayer (Site not responding. Last check: 2007-10-29)
		The purpose of the bilayer membrane is to separate the cell contents from the outside enevrionment.
		The phospholipids are stacked with the non-polar hydrocarbon chains pointed inward while the polar ends act as the external surface as shown in graphic on the left.
		Red/white sphers represent water molecules on the outside surfaces of the bilayer which are hydrophilic (water loving).
	www.elmhurst.edu /~chm/vchembook/553bilayer.html (491 words)

	[No title]
		A slice of the phospholipid bilayer, in which the atoms of one phospholipid molecule are shown as spheres, while all other phospholipid molecules are shown in the stick representation.
		A slice of the phospholipid bilayer, in which the atoms of all phospholipid molecules are shown as spheres.
		in a slice of the bilayer, with the phospholipids shown in the stick representation and the atoms of the water molecules shown as spheres.
	courses.washington.edu /conj/membrane/bilayer.htm (707 words)

	Biochemistry I - Lipid Bilayer (Site not responding. Last check: 2007-10-29)
		A portion of a phospholipid bilayer membrane is shown using the Spacefill display.
		The structure shown on the left corresponds to a bilayer in the gel phase, below its melting temperature.
		See also Dr. Eric Martz' treatment of Lipid Bilayer Membranes to view GIFs of the crystal, gel and fluid models and for downloading the coordinates of each.
	stingray.bio.cmu.edu /~web/bc1/bilayer/Membrane.html (323 words)

	Energetics of Protein-Bilayer Interactions
		The energetic components of the partitioning of peptides and proteins into bilayers are described and equations for calculating free energies of transfer from partitioning measurements are presented.
		An essential feature of their model, subsequently supported by several theoretical studies (3, 4), was that the bilayer interface provided a free energy well for initial binding and folding of hydrophobic peptides.
		Although the preferential association of a solute with the lipid bilayer is frequently treated as macromolecule binding-site problem, the simplest and most rigorous approach is to treat the association as simple partitioning, and use mole-fraction partition coefficients in the computation of standard transfer free energies.
	blanco.biomol.uci.edu /peptide_bilayer_energetics.html (1450 words)

	8.5.3.2
		Lipid bilayer plasma membranes are 6-10 nm thick.
		Cholesterol also acts as a membrane antifreeze agent, decreasing bilayer fluidity at higher temperatures (e.g., raising lipid bilayer "melting point") and preventing hydrocarbon chains of phospholipids from aggregating at lower temperatures (e.g., lowering membrane "freezing point").
		Integral membrane proteins are closely associated with membrane lipids and cannot be extracted from the membrane without disrupting the lipid bilayer.
	www.nanomedicine.com /NMI/8.5.3.2.htm (1638 words)

	chap1
		The formation of a lipid bilayer in water is a self-assembling, 'downhill' process involving rearrangements of water and lipid molecules such that the overall free energy change for the reaction is at a optimum.
		According to this hypothesis, the self-assembled lipid bilayer, the fundamental moiety of biomembranes, is in a dynamic and liquid-crystalline state.
		Since their inception in the early 1960s, such lipid bilayer systems, either in the form of a planar BLM or of a vesicular liposome, have been used extensively as models of biomembranes (Chapter 4).
	www.msu.edu /user/ottova/chap1.html (1858 words)

	Effects of Spontaneous Bilayer Curvature on Influenza Virus-mediated Fusion Pores -- Razinkov et al. 112 (4): 409 -- ...
		The bilayer to hexagonal phase transition of DEPE was measured by differential scanning calorimetry as a function of the mole fraction of R18 and DiI added to the phospholipid.
		For a toroidal pore, the pore wall is a bona fide synthesis of the cell and bilayer membrane.
		Lipid transmembrane asymmetry and flip-flop in biological membranes and in lipid bilayers.
	www.jgp.org /cgi/content/full/112/4/409 (7710 words)

	BCH 4053 Biochemistry I (Site not responding. Last check: 2007-10-29)
		Athough bilayers can be quite extensive, you can see that one problem is that hydrophobic groups are exposed to solvent at the "ends" of the bilayer.
		The bilayer of vesicles has polar surfaces and a hydrophobic middle, and is a barrier to the passage of polar molecules and charged ions into and out of the inner compartment.
		Because of their penetration into the hydrophobic region of the bilayer, integral proteins are not readily separated from the bilayer, and require the addition of detergents to remove and solubilize them.
	wine1.sb.fsu.edu /bch4053/Lecture14/Lecture14.htm (2045 words)

	A SOLVENT MODEL FOR REALISTIC SIMULATIONS OF MEMBRANE-SPANNING PEPTIDES (Site not responding. Last check: 2007-10-29)
		In this approximation the bilayer is usually treated as continuous medium whose properties vary along the membrane thickness, and membrane insertion is simulated using either MC or MD methods.
		The following assumptions were made: (i) properties of the system are constant in the plane of the bilayer (X and Y axes) and vary along Z axis, which is perpendicular to the membrane plane; (ii) thickness of the bilayer is constant; (iii) interaction of protein both with aqueous and membrane environment is given by Eq.
		To change during MC simulation orientation of the peptide with respect to the bilayer, fragment of 12 dummy residues was attached to the N-terminus of GpA.
	www.nmr.ru /publications/ecc5_1/ECCC5_1-Title.html (3402 words)

	Science- Grakoui et al. (Site not responding. Last check: 2007-10-29)
		Free diffusion of GPI anchored molecules in supported planar bilayers is the basis of our approach to imaging the engagement of the fluorescently labeled ligands with cellular receptors.
		T cells move rapidly on the bilayer and fail to induce formation of a bona fide immunological synapse.
		Bilayers were formed on 5 mm round coverlips in 96 well plates.
	www.sciencemag.org /feature/data/1040037.shl (1803 words)

	Lipid bilayer -- Facts, Info, and Encyclopedia article (Site not responding. Last check: 2007-10-29)
		The lipid bilayer is the foundation of all (additional info and facts about biological membrane) biological membranes, and is a prerequisite of (additional info and facts about cell-based) cell-based (The period during which something is functional (as between birth and death)) life.
		The bilayer is composed of two opposing layers of lipid molecules arranged so that their (An organic compound containing only carbon and hydrogen) hydrocarbon tails face one another to form the oily bilayer core, while their electrically charged or polar heads face the watery or "aqueous" solutions on either side of the membrane.
		(An animal sterol that is normally synthesized by the liver; the most abundant steroid in animal tissues) Cholesterol molecules in the bilayer assist in regulating fluidity.
	www.absoluteastronomy.com /encyclopedia/l/li/lipid_bilayer.htm (190 words)

	Projects (Site not responding. Last check: 2007-10-29)
		A pure bilayer is a simple model for the many different membranes of complex composition that surround cells and organells in living creatures.
		The gray atoms in the middle are the carbon atoms from the tails of the lipids.
		It should be clear now where the word 'bilayer' comes from, a membrane has two layers of lipids that face each other with their tails.
	indigo1.biop.ox.ac.uk /tieleman/projects.html (2297 words)

	SparkNotes: Cell Membranes: The Lipid Bilayer
		The lipid bilayer is a universal component of all cell membranes.
		The lipid bilayer is typically about five nanometers thick and surrounds all cells providing the cell membrane structure.
		Structurally, the lipid bilayer is asymmetrical: the lipid and protein composition in each of the two layers is different.
	www.sparknotes.com /biology/cellstructure/cellmembranes/section1.html (476 words)

	Biophysical Journal: Phosphatidylethanolamine-Phosphatidylglycerol Bilayer as a Model of the Inner Bacterial Membrane
		Comparative studies on PE and PC bilayers revealed that the hydrocarbon chain order is higher in PE than in PC bilayers (Urbina et al., 1998; Thurmond et al., 1991) due to a smaller cross sectional area of the PE molecule (Thurmond et al., 1991).
		In this study, a MD simulation was applied to investigate the properties of a bilayer built of PE and PG molecules in the proportion 3:1.
		Mixed phospholipid-charged bilayers, which provide a good model for bacterial membranes, are studied much less frequently than bilayers made of zwitterionic phospholipids that constitute models of eukaryotic membranes.
	www.findarticles.com /p/articles/mi_qa3938/is_200502/ai_n10298353 (1434 words)

	Regulation of Calcium Channel Activity by Lipid Domain Formation in Planar Lipid Bilayers -- Cannon et al. 85 (2): 933 ...
		of HSR membranes to the preformed POPE/POPC bilayer and the
		Huang, H. Deformation free energy of bilayer membrane and its effects on gramicidin channel lifetime.
		Bilayer reconstitution of voltage-dependent ion channels using a microfabricated silicon chip.
	www.biophysj.org /cgi/content/full/85/2/933 (4089 words)

	Energetics of Inclusion-Induced Bilayer Deformations -- Nielsen et al. 74 (4): 1966 -- Biophysical Journal
		(a) The total deformation free energy is determined by the bilayer deformation profile associated with a hydrophobic mismatch between the bilayer and the inclusion.
		The inclusion is treated as a rotationally symmetrical deformation of the bilayer.
		the bilayer adapts to the inclusion induced perturbation.
	www.biophysj.org /cgi/content/full/74/4/1966 (4224 words)

	Discount The North Face Bilayer Jacket - Menss on Sale (Wholesale Mens Windshirts and Jackets)
		The North Face Bilayer Jacket is an amazingly versatile garment that cuts wind out completely and breathes incredibly well making it perfect as a base, mid, or outer layer.
		For this reason, the Bilayer Jacket works beautifully as an outer layer windbreaker in spring and fall or as a base and mid-layer under your Gore-Tex shell for lightweight layering in winter.
		The TNF Bilayer jacket is great - it kept me warm as a middle layer but also doubled as a shell during the peak hours of the day.
	www.backcountrybargain.com /thenorthfacebilayerjacketmens.htm (539 words)

	Biology 202: Membrane Structure & Function
		Lipid bilayers form a barrier to diffusion of hydrophilic molecules.
		are an intrinsic component of the membrane and extend from one side of the lipid bilayer to the other; they cannot be removed without disrupting the membrane.
		The lipid composition on two halves of lipid bilayer are (usually) also different.
	www.sci.sdsu.edu /classes/biology/bio202/TFrey/MembraneStructure.html (1280 words)

	Lipid bilayers and the Gramicidin Channel (Site not responding. Last check: 2007-10-29)
		You will not be able to see the lipid bilayer unless you have the Chime plugin installed.
		Includes a molecular dynamics simulation of the phosphatidylcholine bilayer in water, by H.
		Schulten at the Theoretical Biophysics Group, Beckmann Institute, University of Illinois, Urbana-Champaign, U.S.A. ("Molecular dynamics simulation of a bilayer of 200 lipids in the gel and in the liquid-crystal phases", J.
	molvis.sdsc.edu /bilayers (440 words)

	Molecular Basis of Mechanotransduction in Living Cells -- Hamill and Martinac 81 (2): 685 -- Physiological Reviews
		of the CSK to the bilayer (91, 431).
		of the bilayer as measured by lamellar X-ray diffraction (173).
		bilayer and 3.2 nm for the long axis of alamethicin (115a).
	physrev.physiology.org /cgi/content/full/81/2/685 (8947 words)

	Hydrophobic Coupling of Lipid Bilayer Energetics to Channel Function -- Goforth et al. 121 (5): 477 -- The Journal of ...
		Each individual subunit spans one leaflet of the DPhPC bilayer and is joined at its COOH-terminal to an adjacent subunit, in the same leaflet, by means of a hydrophilic peptide linker, which extends into the aqueous solution.
		To illustrate how the bilayer adapts to the bilayer-spanning channels, the lipids adjacent to or near a channel barrel are depicted with acyl chains that have been shortened by two carbons (second "shell") or four carbons (first "shell"), which represents the bilayer thinning.
		Schematic representation of the formation of double-barreled gramicidin channels in a bilayer with a thickness that is larger than the channel length.
	www.jgp.org /cgi/content/full/121/5/477 (7476 words)

	Physical effects of cholesterol on arterial smooth muscle membranes: evidence of immiscible cholesterol domains and ...
		Under identical conditions as used for data in Figure 1, two separate lamellar phases were present: a membrane lipid bilayer phase (orders 1–4) corresponding to a d-space of 56 Å and an immiscible cholesterol monohydrate phase (orders 1' and 2' corresponding to d) space of 34 Å at 37°C (C:PL mole ratio 0.9:1).
		The reconstituted membrane lipid bilayers were formed at 0.5:1 (6A left) and 1:1 C:PL (6B right) mole ratio to approximate normal and cholesterol-enriched conditions in vivo.
		bilayers in the plane of the cell membrane.
	www.jlr.org /cgi/content/full/39/5/947 (5468 words)

	Gramicidin A channels switch between stretch activation and stretch inactivation depending on bilayer thickness -- ...
		bilayers to achieve the same channel activity (36).
		bilayers with acyl chain lengths as short as 10 (44).
		energetics of bilayer deformation (51), the hydrophobic mismatch
	www.pnas.org /cgi/content/full/99/7/4308 (3859 words)

	Membranes for Modern/Cell Biology (Site not responding. Last check: 2007-10-29)
		Color the carbon atoms in the lower layer a darker gray.
		O molecules back to both sides of the bilayer.
		Similar displays of the gel and fluid phases show more disorder in the fatty acid tails of the phospholipid.
	info.bio.cmu.edu /Courses/BiochemMols/BuildBlocks/Membrane.html (322 words)

	Lipid Bilayers for RasMol (Site not responding. Last check: 2007-10-29)
		PDB files are available for 1-palmitoyl 2-oleoyl phosphatidyl choline bilayers (200 molecules total), hydrated with about 15 layers of water on each side, for various configurations.
		The molecular dynamics simulations which produced these models were done at the Theoretical Biophysics Group of the Beckman Institute at the University of Illinois, Urbana-Champaign by Helmut Heller, Michael Schaefer and Klaus Schulten.
		There is also a movie script of lipid bilayers.
	www.umass.edu /microbio/rasmol/bilayers.htm (293 words)

	Regulation of Sodium Channel Function by Bilayer Elasticity: The Importance of Hydrophobic Coupling. Effects of ...
		Membrane proteins are regulated by the lipid bilayer composition.
		(A) Formation of a gA channel by the trans-bilayer association of two monomers causes a bilayer deformation that involves the compression and bending of the bilayer leaflets adjacent to the channel.
		The total free energy change associated with the protein conformational change is the sum of the free energy change associated with the intrinsic rearrangement of the protein and the free energy change associated with the bilayer deformation.
	www.jgp.org /cgi/content/full/123/5/599 (7015 words)

	Reasons To Believe: Facts For Faith Issue 10, 2002
		The strict requirements needed for bilayer formation make it unlikely that the amphiphilic compounds in meteorites or comets delivered to Earth could have contributed to the formation of the first protocell membranes.
		This model views the phospholipid bilayer as a two-dimensional fluid that serves as both a cellular barrier and as a solvent for integral membrane proteins.
		Lionel Ginsberg et al., “Membrane Bilayer Assembly in Neural Tissue of Rat and Squid as a Critical Phenomena: Influence of Temperature and Membrane Proteins,” Journal of Membrane Biology 119 (1991): 65-73.
	www.reasons.org /resources/fff/2002issue10/index.shtml?main (17268 words)

	Reasons To Believe: Facts For Faith Issue 10, 2002
		Formation of nonanoic acid bilayers (or bilayers comprised of any amphiphile with a single hydrocarbon chain) is as improbable as a river flowing up a mountain, since several “just right” conditions need to be met simultaneously.
		Many phospholipids spontaneously form bilayers that stack into sheets (multilamellar bilayers) that are either linear or spherical in shape.
		Bilayer fluidity also varies from region to region in the cell membrane.
	www.reasons.org /resources/fff/2002issue10/index.shtml (17268 words)

	From the Cover: Elastic coupling of integral membrane protein stability to lipid bilayer forces -- Hong and Tamm 101 ...
		and overall curvature of the lipid bilayer (18).
		The large fl arrows indicate lateral bilayer pressure imparted on the lipid/protein interface in the hydrophobic core (red) of bilayers composed of lipids with negative intrinsic spontaneous curvature.
		When folding into thin bilayers (right path), the process is multistate, i.e., at least one equilibrium intermediate occurs.
	www.pnas.org /cgi/content/full/101/12/4065 (3237 words)

Try your search on: Qwika (all wikis)