Showing papers in "Biochimica et Biophysica Acta in 1976"

TL;DR: Observations on the molecular basis of pleiotropic drug resistance are interpreted in terms of a model wherein certain surface glycoproteins control drug permeation by modulating the properties of hydrophobic membrane regions.

TL;DR: Evidence concerning the reasons for these alterations and the possible functions of some of the molecules is reviewed, and particular emphasis is placed on the idea that surface molecules are associated in specific non-covalent complexes which are important for their functions.

TL;DR: A fluorescence polarization technique with 1,6-diphenyl 1,3,5-hexatriene as a probe was employed to determine the microviscosity, n, in liposomes and biological membranes of different cholesterol to phospholipid mol ratio and the degree of rotational mobility of concanavalin A receptor sites in cell membranes was determined.

TL;DR: The DNAase digestion end-product of calf thymus DNA contains oligonucleotides that will function as primers for the efficient transcription into DNA of many naturally-occurring RNA's by purified avian sarcoma virus RNA-directed DNA polymerase.

TL;DR: The following findings indicate that the catecholamine-stimulated GTPase is independent of the catalytic production of cyclic AMP by the adenylate cyclase.

TL;DR: Liposomes, in the size range of microsomal vesicles, are formed when ether solutions of a variety of lipids are injected into warm aqueous solutions and the volume trapping efficiency is approximately ten times that of sonicated and hand-shaken preparations.

TL;DR: When platelets, so labelled, were washed and treated with thrombin, there was a major decrease in the radioactivity of phosphatidylcholine and phosph atidylinositol, accounted for by the appearance of several previously identified 14C-labelled oxygenated products of arachidonic acid.

TL;DR: The functional role of the hydrogen bonding groups in the ceramide part of sphingolipids is emphasized and their significance for the formation of lateral hydrogen bonds within the membrane layer and thereof arising effects on membrane stability and permeability are discussed.

TL;DR: It is suggested that most hydrophilic antibiotics diffuse through aqueous pores, whereas hydrophobic antibiotics and dyes mainly penetrate by dissolving into the hydrocarbon interior of the out membrane.

TL;DR: A homogeneous population of pure lecithin single-bilayer vesicles free of multilamellar structures is obtained, and the vesicle diameter is somewhat larger than the average diameter of sonication.

TL;DR: The soluble hydrogenase from Alcaligenes eutrophus H 16 was purified 68-fold with a yield of 20% and a final specific activity (NAD reduction) of about 54 mumol H2 oxidized/min per mg protein, and was shown to be homogenous by polyacrylamide gel electrophoresis.

TL;DR: Isolation of different proteins of the phosphotransferase system and reconstitution of the complex shows that in the net transfer of the phosphate group from phosphoenolpyruvate to a given sugar the phosphoryl group is sequentially transferred from one protein to another.

TL;DR: In equimolar mixtures of phosphatidylcholine-phosphatidylethanolamine mixtures at temperatures where both components are in the liquid-crystalline state cholesterol is preferently associated with the phosphatidocholine component in the mixture.

TL;DR: The kinetic behavior or the purified lung soluble gluthathione peroxidase followed a ping-pong-like mechanism; the enzyme first reduced the lipid hydroperoxide substrate to the corresponding hydroxy fatty acid, then was regenerated to the native form by reduced glutathione.

TL;DR: It is suggested that under these conditions membranes become transiently susceptible to fusion as a result of changes in molecular packing and creation of new phase boundaries induced by Ca2+ (or Mg2+).

TL;DR: The absence of protein in these lipid vesicles implies that all the proteins of the erythrocyte membrane are immobilized by association with either the spectrin meshwork or the intramembrane particles.

TL;DR: 5,8,11,14-Eicostetraynoic acid and nordihydroguaiaretic acid inhibited 12ho-20:4 formation in spleen homogenates whereas indomethacin and arachidonic acid stimulated it.

TL;DR: A new high-resolution preparative column chromatographic system was developed for efficient and rapid isolation of ganglioside molecular species, achieving high purity and in milligram amounts, in a relatively short time.

TL;DR: The mechanism of oxidative phosphorylation is one of the most important problems in classical biochemistry, which has defied a solution for over thirty years as discussed by the authors, and recent studies of photo-affinity labeling and equilibrium binding by uncouplers have contributed new insights into this problem.

TL;DR: The value determined for the redox potentials of O 2/O2 is higher by more than 0.2 V than earlier estimates, which has important implications on the possible role of O2 in biological processes of O1 fixation.

TL;DR: It appears, therefore, that glutathione peroxidase activity must exert its effect on this system by preventing free radical attack on the polyunsaturated membrane lipids in the first place.

TL;DR: The results of this comparison indicate that the membrane fragments found in the culture supernatant of normally growing Escherichia coli consist of practically unmodified outer membrane.