Membrane hydrophobic interactions

Proteins contain many nonpolar side chains. These side chains are repelled by water and tend to associate with one another on the inside of a folded protein molecule, out of contact with water. The tendency of nonpolar side chains to collect out of contact with the solvent is called the hydrophobic effect. The hydrophobic interactions in proteins are similar to those in the micelle of a soap (Section 21.5) or the bilayer of lipids in membranes. Hydrophobic interactions among nonpolar side chains in proteins are weak, but abundant, and are primarily responsible for maintaining the folded conformation of a protein. 

Ionic interactions between solutes and Superose are negligible at ionic strengths above 50 mM. However, some hydrophobic interactions have been observed with small hydrophobic peptides, membrane proteins, and lipopro-... 

The squaraine probe 9g was tested for its sensitivity to trace the formation of protein-lipid complexes [57]. The binding of dye 9g to model membranes composed of zwitter-ionic lipid phosphatidylcholine (PC) and its mixtures with anionic lipid cardiolipin (CL) in different molar ratios was found to be controlled mainly by hydrophobic interactions. Lysozyme (Lz) and ribonuclease A (RNase) influenced the association of 9g with lipid vesicles. The magnitude of this effect was much higher... 

Growth conditions of Synechocystis sp. PCC 6803 and subsequent isolation of thylakoid membranes were described in literature [8], From these membranes, PS I was extracted by dodecyl-B-D-maltoside treatment and purified by two successive HPLC steps, using first an anion exchange column (Poros 50 HQ, PerSeptive) and second a hydrophobic interaction column (Poros 20 Butyl, PerSeptive). The purification of trimeric PS I is described in detail in literature [9],... 

Additionally the membrane itself can contribute to further modifications of the protein-protein interactions. It can provide additional electrostatic and hydrophobic interactions distinct from the lipid anchorage and thereby affect conformation and/or activity of membrane associated proteins. 

Solvent-resistant elastomers, 9 560-562 Solvent-resistant membranes, 27 656 Solvent-resistant rubber, 22 583-584 Solvent selection, in liquid-liquid extraction, 70 746-749 Solvent-solute interactions, 26 855,23 91-96 acid/base interactions in, 23 96 dispersion in, 23 92-93 electrostatic forces in, 23 91-92 hydrogen bonding in, 23 94-95 hydrophobic interactions in, 23 95 polarization in, 23 92 repulsion in, 23 93-94 Solvent strength, of pure fluids, 24 3-4 Solvent systems, for acid gas removal, 72 376-377... 

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