Helix rotation

Helix rotation sense Right-handed Right-handed Left-handed... 

Helix as pump Core rotates opposite of helix rotation b) c)... 

Figure 8.10 Experimental and numerical determination of the RTD of three drops extruded when the free helix extruder is operated with just the helix rotating (core is stationary)...

A7.1.3 z-Directional Flow for Helix Rotation with a Stationary Screw Core and Barrel ... 

Fillingame, R. H., Angevine, C. M., and Dmitriev, O. Y. (2002). Coupling proton movements to c-ring rotation in F(1)F(0) ATP synthase Aqueous access channels and helix rotations at the a-c interface. Biochim. Biophys. Acta. 1555, 29-36. 

Whether or not transmembrane helix rotation is a crucial event that leads to receptor activation in the case of TNER superfamily, a net effect of ligand binding and receptor activation appears to be the induced closer proximity of the intracellular domains (Eig. 12A), as shovm by fluorescence energy transfer experiments (Ghan et al, 2000). In the structures of TRAF-receptor complexes, the distance between bound receptor peptides is approximately 50 A. This suggests that a distance of separation between the intracellular domains of receptor chains on the order of 50 A may be optimal for TRAP recruitment and signaling transduction. 

The W-C DNA structure is a right-handed helix as one looks down either axis of the molecule and the helix rotates in a clockwise direction. This conformation of DNA is called B-DNA and is the form found in solution and inside cells. The double helix is stabilized by a number of forces, including hydrophobic interactions and van der Waals forces, which also help stabilize single polynucleotide chains. Collectively, these two forces are known as stacking interactions because of their contribution to the stacked arrangement of the bases in DNA. 

There are ten bases per turn of the helix, so the helix rotates 36 per base. 

The next helix rotates into position for a half-length chaimel site and releases its proton to the opposite side of the membrane. 

R.H. Fillingame, C.M. Angevine, and O.Y. Dmitriev, Coupling Proton Movements to c-Ring Rotation in FIFO ATP Synthase Aqueous Access Channels and Helix Rotations at the a-c Interface. Biochim. Biophys. Acta, 1555, 29-36,2002. 

According to the Watson-Crick model, two helically arranged chains are wound around each other to produce a double helix in double-strand deoxyribonucleic acids (Figure 29-2). The double helix rotates upward in a clockwise direction (P-helix). The screwlike rotation of the strands causes periodically recurring large and small furrows to occur at 2.2 or 1.2 nm. Thus, after 3.4 nm or ten base pairs, a complete rotation has occurred. The double helix diameter is about 2 nm. 

Figure 5.11 contains a selection of projections of rational helices that correspond to the indicated screw axes. If there is no equivalent screw axis indicated, it does not exist in space-lattice symmetry. The helix lattice generates the complete molecule starting with the first motif, but one must specify whether the helix rotation is left- or right-handed. While the screw axis 3j corresponds to aright-handed 3/1 helix, the 32 screw axis generates a left-handed 3/1 helix, but every second lattice point is generated... 

Camber results when one side of the material is longer than the other, producing a curvature in the product the hard way (Fig, 8). From a geometry point of view, if we twist a cambered strip, it will become a helix rotating around the short edge, which becomes the center of rotation. 

Fig. 5 Left. The 12 important helix pair interactions. Right. The BiHelix concept in which the interhelical interactions are optimized for a pair of helix rotations, while ignoring the other 5...

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