Hydrophobic elastic

Relevance of the Hydrophobic Elastic Consilient Mechanism to the Fj-motor Functioning as an ATPase Analogy to the Internal Combustion Rotary Engine... 

Thus the fundamental predictions of the hydrophobic elastic consilient mechanism are that the rotor would exhibit asymmetric hydrophobicity, that different arrangements of nucleotide analogues representing different states of polarity at the catalytic sites would orient the rotor, and that hydrolysis of ATP in formation of the most polar state at a catalytic site of the involved protein subunit(s) would demonstrate a near-ideal elastic deformation of the y-rotor and the protein subunit(s). Of course, such a mechanism would exhibit high efficiency and reversibility. 

Demonstrations of these predictions constitute the message of this section 8.4, and its success introduces the perspective of a conjoined hydrophobic elastic consilient mechanism. With the values in Table 5.3 and the crystal structure with three different states of occupancy, empty, ATP, and ADP, the three sides of the rotor can be identified and the respective Gibbs free energies of hydrophobic association, AGha, have been estimated to be -20, 0, and +9kcal/mole. The most hydrophobic face associates with the empty site, the neutral face with the ATP bound site, and the most polar face with the ADP site which in the synthesis mode would be in position to add Pj. As expected from the magnitude of the resulting AG,p for a series of crystal structures wherein the least polar occupancy state for the catalytic site could be defined, the most hydrophobic side of the rotor resides in apposition to the least polar site. 

The rotor that is driven by the Fo-motor comprises a single y-subunit and a small e-subunit attached to the y-subunit at a point proximal to the base of the Fo-motor. This is called the y-rotor. In the hydrophobic elastic consilient mechanism, the interactions of a hydrophobi-cally asymmetric y-rotor with the housing of the Fi-motor with different occupancy states of the catalytic sites constitute the basis for mechano-chemical transduction of the Fi-motor. 

Review of Correlations Between the Hydrophobic Elastic Consilient Mechanism and the Properties of ATP Synthase/Fj-ATPase... 

In the eighth point of correlation of the hydrophobic elastic consilient mechanism given above, the maximal stage of apolar-polar repulsion occurred when the most polar occupancy state, ADP Mg plus HPOJ", faced off against the most hydrophobic side of the y-rotor to provide the thrust for a counterclockwise... 

E.2.9.3 Bursts of Apolar-Polar Repulsive Free Energy on Hydrolysis of ATP, by the Hydrophobic Elastic Consilient Mechanism, Can Convert to Elastic Deformation for Efficient Energy Conversion... 

Preparation of chemically cross-linked fibers Chemical cross-linking was achieved by extrusion of solutions of E- and K- pairs of polymers at equal concentrations of functional groups into a saturated solution at 50 C of water soluble carbodiimide (EDC, l-(3-dimethy-laminopropyl)-3-ethylcarbodiimide) to form amide bonds between the carboxyl of glutamic acid (E) residues and the e-amino groups of lysine (K) residues. When in an adequately hydrophobic elastic protein-based polymer, the charged carboxylate and amino functions experience a driving force for ion-pairing. The force... 

Nylon-11. Nylon-11 [25035-04-5] made by the polycondensation of 11-aminoundecanoic acid [2432-99-7] was first prepared by Carothers in 1935 but was first produced commercially in 1955 in France under the trade name Kilsan (167) Kilsan is a registered trademark of Elf Atochem Company. The polymer is prepared in a continuous process using phosphoric or hypophosphoric acid as a catalyst under inert atmosphere at ambient pressure. The total extractable content is low (0.5%) compared to nylon-6 (168). The polymer is hydrophobic, with a low melt point (T = 190° C), and has excellent electrical insulating properties. The effect of formic acid on the swelling behavior of nylon-11 has been studied (169), and such a treatment is claimed to produce a hard elastic fiber (170). 

The coacervation of tropoelastin plays a crucial role in the assembly into elastic fibers. This coacervation is based on the LCST behavior of tropoelastin, which causes tropoelastins structure to become ordered upon raising the temperature. The loss of entropy of the biopolymer is compensated by the release of water from its chain [2, 18, 19]. This release of water results in dehydration of the hydrophobic side chains, and this is the onset of the self-assembly leading to the alignment of tropoelastin molecules. 

Summary Hydrophobic aerogels were prepared by base-catalyzed hydrolysis and condensation of RSi(OMe)3 (R = Me, Ph, PrI1)/Si(OMe)4 (1 4) mixtures in methanol, followed by supercritical drying of the obtained alcogels with methanol. The organic substituents also increase the elasticity of the aerogels. 

The rheological properties of a fluid interface may be characterized by four parameters surface shear viscosity and elasticity, and surface dilational viscosity and elasticity. When polymer monolayers are present at such interfaces, viscoelastic behavior has been observed (1,2), but theoretical progress has been slow. The adsorption of amphiphilic polymers at the interface in liquid emulsions stabilizes the particles mainly through osmotic pressure developed upon close approach. This has become known as steric stabilization (3,4.5). In this paper, the dynamic behavior of amphiphilic, hydrophobically modified hydroxyethyl celluloses (HM-HEC), was studied. In previous studies HM-HEC s were found to greatly reduce liquid/liquid interfacial tensions even at very low polymer concentrations, and were extremely effective emulsifiers for organic liquids in water (6). 

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