Lens Major Intrinsic Protein (MIP)
... the plasmatic membranes of the lens fibers. The aim of our studies was to test the adhesion-promoting role of MIP. W e reconstituted M I P into large unilamellar vesicles (LUV) of phosphatidylcholine (PC) and studied the vesicle aggregation between MIP-reconstituted LUV (PC-MIP) and phosphatidylseri ...
... the plasmatic membranes of the lens fibers. The aim of our studies was to test the adhesion-promoting role of MIP. W e reconstituted M I P into large unilamellar vesicles (LUV) of phosphatidylcholine (PC) and studied the vesicle aggregation between MIP-reconstituted LUV (PC-MIP) and phosphatidylseri ...
ref. #29 of the TIBS article
... domain in mutants where the acceptor Asn is too close to the membrane for efficient glycosylation is still translocated into the lumen of the microsomes (18), and thus that the degree of glycosylation is an accurate measure of the location of the Asn relative to the OST active site. Effects of Trp a ...
... domain in mutants where the acceptor Asn is too close to the membrane for efficient glycosylation is still translocated into the lumen of the microsomes (18), and thus that the degree of glycosylation is an accurate measure of the location of the Asn relative to the OST active site. Effects of Trp a ...
actin filament-membrane attachment: are membrane particles
... been documented for several systems. In microvilli, for example, an examination of stages in the reextension of microvilli after pressure-induced disassembly revealed that the actin filaments assemble from a dense material associated with the limiting membrane and from there elongate (40). Similar o ...
... been documented for several systems. In microvilli, for example, an examination of stages in the reextension of microvilli after pressure-induced disassembly revealed that the actin filaments assemble from a dense material associated with the limiting membrane and from there elongate (40). Similar o ...
Ultrastructural studies of t /t mouse embryos
... Both homozygotes can be distinguished from their litter-mates as early as the 2-cell stage by the presence of nuclear lipid droplets and excessive cytoplasmic lipid. In addition, both homozygous mutant embryos often contain binucleate cells, especially in the later cleavage stages. Usually there is ...
... Both homozygotes can be distinguished from their litter-mates as early as the 2-cell stage by the presence of nuclear lipid droplets and excessive cytoplasmic lipid. In addition, both homozygous mutant embryos often contain binucleate cells, especially in the later cleavage stages. Usually there is ...
Theoretical studies of Membrane Proteins
... The stage for this thesis is set in the membrane of living cells. These membranes are composed of a lipid bilayer which serves to separate different compartments of the cell, or in the case of lower organisms, the cell from its environment. Membranes are impermeable to polar molecules (soluble in wa ...
... The stage for this thesis is set in the membrane of living cells. These membranes are composed of a lipid bilayer which serves to separate different compartments of the cell, or in the case of lower organisms, the cell from its environment. Membranes are impermeable to polar molecules (soluble in wa ...
Vesicular transport of newly synthesized opsin from the Golgi
... and printed at a final magnification of XI 8,000. The use of all visible cells rather than a selected midcellular sample yielded a random collection of cells sectioned in different axial planes. In order to estimate the relative degree of labeling of various sources within photoreceptor inner segmen ...
... and printed at a final magnification of XI 8,000. The use of all visible cells rather than a selected midcellular sample yielded a random collection of cells sectioned in different axial planes. In order to estimate the relative degree of labeling of various sources within photoreceptor inner segmen ...
isolation and characterization of membranes from the cells of maize
... cytoplasmic vesicles (Northcote, 1971, 1974). Some of the components of the system are joined by structural connexions and they all have a functional continuity in the cytoplasm of eukaryotic cells (Morr6 & Ovtracht, 1977). It is now generally believed that the endomembrane system is present in a dy ...
... cytoplasmic vesicles (Northcote, 1971, 1974). Some of the components of the system are joined by structural connexions and they all have a functional continuity in the cytoplasm of eukaryotic cells (Morr6 & Ovtracht, 1977). It is now generally believed that the endomembrane system is present in a dy ...
University of Groningen The Plasma Membrane of
... teins are often hindered in their lateral motion because of association with other proteins or association with elements of the cytoskeleton or extracellular matrix. Another dominant feature of membrane structure is the asymmetric location of the proteins. Some span the entire length of the membrane ...
... teins are often hindered in their lateral motion because of association with other proteins or association with elements of the cytoskeleton or extracellular matrix. Another dominant feature of membrane structure is the asymmetric location of the proteins. Some span the entire length of the membrane ...
Structure of the Transmembrane Cysteine Residues in
... of the acetylcholine receptor from Torpedo marmorata have led to a molecular structure at 9 Å resolution (Unwin, 1993). The structure is formed from five similar subunits each contributing a transmembrane helix (designated M2) to create a central ion pore. Upon exposing the channel to acetylcholine, ...
... of the acetylcholine receptor from Torpedo marmorata have led to a molecular structure at 9 Å resolution (Unwin, 1993). The structure is formed from five similar subunits each contributing a transmembrane helix (designated M2) to create a central ion pore. Upon exposing the channel to acetylcholine, ...
Force development by the contractile vacuole
... and the mineral oil, the CV rounded against this force during its rounding phase. It can, therefore, be supposed that the tension at the surface of the CV increases during the rounding phase. We previously proposed a hypothesis (Tominaga et al., 1998a; Tominaga et al., 1999) that an increase in the ...
... and the mineral oil, the CV rounded against this force during its rounding phase. It can, therefore, be supposed that the tension at the surface of the CV increases during the rounding phase. We previously proposed a hypothesis (Tominaga et al., 1998a; Tominaga et al., 1999) that an increase in the ...
The Membrane Steps of Bacterial Cell Wall Synthesis as Antibiotic
... in E. coli MraY (EcMraY)), were addressed in this study [36]. It was the first time that MraY catalysis was studied with purified enzyme, both the wild-type and its mutants, without the interference of other contaminant enzymes or traces of C55-P in a membrane preparation. Fourteen single mutations ...
... in E. coli MraY (EcMraY)), were addressed in this study [36]. It was the first time that MraY catalysis was studied with purified enzyme, both the wild-type and its mutants, without the interference of other contaminant enzymes or traces of C55-P in a membrane preparation. Fourteen single mutations ...
Bugging the cell wall of bacteria
... main function of the bacterial cell wall is to provide the cell with strength required to withstand the high internal osmotic pressure. The only class of bacteria devoid of a cell wall, the mycoplasmas, are therefore osmotically fragile. They have a parasitic lifestyle and rely on their host cells f ...
... main function of the bacterial cell wall is to provide the cell with strength required to withstand the high internal osmotic pressure. The only class of bacteria devoid of a cell wall, the mycoplasmas, are therefore osmotically fragile. They have a parasitic lifestyle and rely on their host cells f ...
In-Cell Solid-State NMR - Institut de Biologie Physico
... of samples can qualify as in cell: living cells (in vivo NMR), intact cells, and intact cellular compartments such as organelles and cellular envelopes (in situ NMR). Biological cells were studied by NMR as early as 1955 (1), and 15 years later the focus shifted from looking at water molecules to ex ...
... of samples can qualify as in cell: living cells (in vivo NMR), intact cells, and intact cellular compartments such as organelles and cellular envelopes (in situ NMR). Biological cells were studied by NMR as early as 1955 (1), and 15 years later the focus shifted from looking at water molecules to ex ...
Structure and mechanism of ATP-dependent phospholipid transporters
... transporter is divided into three major domains; The Actuator domain (A), the Nucleotide binding domain (N) and the phosphorylation domain (P). The P4-ATPases in addition to the αsubunit consist of a β-subunit with two transmembrane spans and a large exoplasmic loop. (D) Model of ion transport throu ...
... transporter is divided into three major domains; The Actuator domain (A), the Nucleotide binding domain (N) and the phosphorylation domain (P). The P4-ATPases in addition to the αsubunit consist of a β-subunit with two transmembrane spans and a large exoplasmic loop. (D) Model of ion transport throu ...
Phosphatidylinositol 4-Phosphate Formation at ER Exit Sites
... Nevertheless, the affinities of coat-cargo interactions are relatively low and may not support cargo recognition by themselves (Miller et al., 2003; Mossessova et al., 2003). Regulated enhancement of the binding avidity between cargo and the coat at ERES may provide a plausible mechanism to control ...
... Nevertheless, the affinities of coat-cargo interactions are relatively low and may not support cargo recognition by themselves (Miller et al., 2003; Mossessova et al., 2003). Regulated enhancement of the binding avidity between cargo and the coat at ERES may provide a plausible mechanism to control ...
Fractionation of Membranes from Metschnikowi`a
... since the cytosol of M . reukarrfii has a pH of 6-2(Aldermann & Hiifer, 1981). The idination of tyrosine residues of plasma-membrane proteins occurs at pH 7.5 in the presence of H 2 0 2and lactopcroxidase (Phillips & Morrison, 1970; 1971).The size of lactoperoxidase molecules (mol. wt 78000) prevent ...
... since the cytosol of M . reukarrfii has a pH of 6-2(Aldermann & Hiifer, 1981). The idination of tyrosine residues of plasma-membrane proteins occurs at pH 7.5 in the presence of H 2 0 2and lactopcroxidase (Phillips & Morrison, 1970; 1971).The size of lactoperoxidase molecules (mol. wt 78000) prevent ...
Structure and properties of the outer membranes of Brucella abortus
... Group 2 Two closely linked genes (omp2a and omp2b) encode porin proteins with a high degree (> 85%) of homology [16]. Interestingly, only Omp2b is expressed in laboratory grown B. abortus [25] but, although its expression in Brucella has not been observed, Omp2a increases the permeability to maltode ...
... Group 2 Two closely linked genes (omp2a and omp2b) encode porin proteins with a high degree (> 85%) of homology [16]. Interestingly, only Omp2b is expressed in laboratory grown B. abortus [25] but, although its expression in Brucella has not been observed, Omp2a increases the permeability to maltode ...
Regulation of phospholipase D activity, membrane targeting and
... Direct regulation of PLD by protein kinases, small GTPases and other interacting proteins couples cell surface receptors to activation of intracellular PLD activity. PLD-generated PA is an intracellular signalling lipid that regulates the actin cytoskeleton and controls pathways that regulate cell g ...
... Direct regulation of PLD by protein kinases, small GTPases and other interacting proteins couples cell surface receptors to activation of intracellular PLD activity. PLD-generated PA is an intracellular signalling lipid that regulates the actin cytoskeleton and controls pathways that regulate cell g ...
The Neuronal Membrane at Rest
... hydrophobic and will tend to associate readily with lipid. Regions with exposed polar R groups will be hydrophilic and will tend to avoid a lipid environment. Therefore, it is not difficult to imagine classes of rod-shaped proteins with polar groups exposed at either end, but with only hydrophobic g ...
... hydrophobic and will tend to associate readily with lipid. Regions with exposed polar R groups will be hydrophilic and will tend to avoid a lipid environment. Therefore, it is not difficult to imagine classes of rod-shaped proteins with polar groups exposed at either end, but with only hydrophobic g ...
protein membranes as models of cosmetic ingredients penetration
... the positively charged keratin, and as well diffusion is retard (18). Difficulty in evaluation of products for nail apparatus diseases is mainly caused by the lack in proper in vitro model for penetration through nail plate. Because of that many studies have been caring out to simulate penetration t ...
... the positively charged keratin, and as well diffusion is retard (18). Difficulty in evaluation of products for nail apparatus diseases is mainly caused by the lack in proper in vitro model for penetration through nail plate. Because of that many studies have been caring out to simulate penetration t ...
Lipid bilayer
The lipid bilayer is a thin polar membrane made of two layers of lipid molecules. These membranes are flat sheets that form a continuous barrier around all cells. The cell membranes of almost all living organisms and many viruses are made of a lipid bilayer, as are the membranes surrounding the cell nucleus and other sub-cellular structures. The lipid bilayer is the barrier that keeps ions, proteins and other molecules where they are needed and prevents them from diffusing into areas where they should not be. Lipid bilayers are ideally suited to this role because, even though they are only a few nanometers in width, they are impermeable to most water-soluble (hydrophilic) molecules. Bilayers are particularly impermeable to ions, which allows cells to regulate salt concentrations and pH by transporting ions across their membranes using proteins called ion pumps.Biological bilayers are usually composed of amphiphilic phospholipids that have a hydrophilic phosphate head and a hydrophobic tail consisting of two fatty acid chains. Phospholipids with certain head groups can alter the surface chemistry of a bilayer and can, for example, serve as signals as well as ""anchors"" for other molecules in the membranes of cells. Just like the heads, the tails of lipids can also affect membrane properties, for instance by determining the phase of the bilayer. The bilayer can adopt a solid gel phase state at lower temperatures but undergo phase transition to a fluid state at higher temperatures, and the chemical properties of the lipids' tails influence at which temperature this happens. The packing of lipids within the bilayer also affects its mechanical properties, including its resistance to stretching and bending. Many of these properties have been studied with the use of artificial ""model"" bilayers produced in a lab. Vesicles made by model bilayers have also been used clinically to deliver drugs.Biological membranes typically include several types of molecules other than phospholipids. A particularly important example in animal cells is cholesterol, which helps strengthen the bilayer and decrease its permeability. Cholesterol also helps regulate the activity of certain integral membrane proteins. Integral membrane proteins function when incorporated into a lipid bilayer, and they are held tightly to lipid bilayer with the help of an annular lipid shell. Because bilayers define the boundaries of the cell and its compartments, these membrane proteins are involved in many intra- and inter-cellular signaling processes. Certain kinds of membrane proteins are involved in the process of fusing two bilayers together. This fusion allows the joining of two distinct structures as in the fertilization of an egg by sperm or the entry of a virus into a cell. Because lipid bilayers are quite fragile and invisible in a traditional microscope, they are a challenge to study. Experiments on bilayers often require advanced techniques like electron microscopy and atomic force microscopy.