Fivefold symmetry axis

A view down the fivefold symmetry axis of the icosahedtal structure (a) shows that the central capsomer is pentameric in shape and surrounded by five other capsomers as expected. The view down the pseudosixfold axis (h) shows, however, that the central capsomer is pentameric in shape and not hexameric as required for a T = 7 structure. (Adapted from 1. Rayment et al., Nature 295 110-115, 1982, hy copyright permission of Macmillan Magazines Limited.)... 

Penrose tiling with a fivefold symmetry axis consisting of two kinds of rhomboid tiles... 

The crystal structure of Tb MscL established that this protein assembles as a homopentamer that is organized into two domains, the transmembrane domain and the cytoplasmic domain. The transmembrane domain consists of 10 helices (2 per subunit) connected by an extracellular loop, while the cytoplasmic domain contains 5 helices that form a left-handed pentameric bundle. The sequence of the Tb.MscL subunit has 151 amino acids and can be further subdivided into five segments the N terminus, the first transmembrane helix (TM1), an extracellular loop, the second transmembrane helix (TM2), and a cytoplasmic domain (Fig. 4, see color insert). Each of the segments is discussed in more detail below. The pore is aligned along the fivefold symmetry axis and is formed by the first transmembrane helix (TM1) and an extracellular loop from each subunit. The channel has overall dimensions of approximately 85 x 50 x 50 A and both the N and C termini reside on the... 

The MCD spectrum of the croconate dianion CjO, is shown in Figure 3.10. The molecule possesses a fivefold symmetry axis and belongs to the point... 

Figure 6. Several models in the DIC sequence from the primitive IC N = 13) to the last model N = 45). Pentagonal rings are constructed on the primitive IC and form pentagonal pyramids with the outer (white) atoms. DIC axes passing through the center of the primitive IC have been drawn. The N = 34 model has a fivefold symmetry axis. The dodecahedral second layer is visible on the centrosymmetrical model N - 45.

In each of the relaxed models we calculated the distances between nearest-neighbor atoms on the fivefold symmetry axis, that is, between the vertices of successive layers. Figure 12a gives the distances d between the vertices of... 

However, we have to assume that only FCC particles are active. In fact, from this experiment we cannot exclude that the particles with a fivefold symmetry axis are active. 

The molecule possesses a fivefold symmetry axis and belongs to the point... 

On a large scale (>100 nm), the fivefold surfaces (orthogonal to the fivefold symmetry axis) present sequences of flat terraces with characteristic terrace step heights... 

Z, a position of the penetration of a fivefold symmetry axis (in E ) into a single terminating layer. 

Figure Bl.8.6. An electron diffraction pattern looking down the fivefold symmetry axis of a quasicrystal. Because Friedel s law introduces a centre of symmetry, the symmetry of the pattern is tenfold. (Courtesy of L Bendersky.)...

A decade ago Dan Schechtman synthesized a crystalline solid of manganese and aluminum that according to its X-ray diffractogram has a fivefold symmetry axis. If this material is heated, it first becomes amorphous, but at higher temperatures the... 

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