2D crystals

PM. The intense three peaks indicated by the grey in the top trace are ascribed to three Ala residues in the a-helix (helix G in this figure) protruding from the cytoplasmic membrane surface and four Ala residue in the C-terminal. (C) Schematic representation of the dynamic structure of bR in 2D crystal. The interfacial and kinked portions are illustrated by the shade and belts, respectively. From Refs. 22 and 179 with permission. 

Dynamic picture of bR from PM in 2D crystal A dynamic picture of bR in the 2D crystal thus obtained turns out to be highly heterogeneous the correlation times of which vary substantially from 10 2 to < 10 8 s depending upon the portions such as the TM and CP a-helices, loops, and N- or C-terminal ends (Figure 24C). Here, the above mentioned CP... 

Figure 36 Schematic representation of dynamic picture of bR in monomer. See the correlation times for the cytoplasmic and extracellular loops and transmembrane a-helices are significantly shortened as compared with those in 2D crystal as shown in Figure 24.

There are several ways to model the substrate. The simplest would be to consider the substrate as a structureless attractive wall. However, since we want the polymer molecules to be parallel to each other on the substrate, we impose a directional force. In 2D crystallization, we took the substrate structure into account by use of the continuous substrate potential t/2, a sort of mean field potential that restricts the molecular motion on the substrate [20] ... 

In our study of 2D crystallization, we assumed that the two dimensional substrate potential is only a function of x as in Eq. 4. Here again we take the... 

Various structures of DNA tubes have been devised based on the main building blocks exploited in 2D crystals four-arm junctions [73] and different kinds of DX [68] and TX tiles [101]. The spontaneous curvature of DNA constructs is in this case exploited rather than minimized or compensated as in 2D crystals. Specifically, the curvature is the consequence of the symmetry of the different tiles and of the nature, the number, and the spatial arrangement of the crossover points, whose ultimate origin is an implementation of the approach proposed in [100] and shown in Fig. 22 (see [102] for a detailed discussion). 

Fig. 39 Aggregation of colloids coated with long DNA strands above a sticky surface leads to flying carpets, floating 2D crystals, (a) Confocal microscopy image of a flying carpet (scale bar is 10 pm), (b) Pair correlation function of the structure depicted in (a). The observed peaks match those expected for a perfect hexagonal crystal (black triangles). Reproduced with permission from [165]...

Fig. 7 Chiral packing of rod- and disk-shaped molecules in 2D crystal lattice...

The wings extend sideways from the body domains perpendicular to the central symmetry axis of the tetramer and could participate in the binding to some receptors (see Sections 2.3 and 4). They also seem to mediate homotypic interactions, causing tetramers to assemble into flat 2D crystals, often containing large numbers of tetramers (Lunev et al. 1991). These lattices could underlie the frequently described phenomenon of a-LTX channel clusterization (Robello et al. 1987 Krasilnikov and Sabirov 1992 Filippov et al. 1994 Van Renterghem et al. 2000). 

Electron crystallography has proven to be a valuable tool for analysis of tubulin structure and drug interactions. Likewise, tubulin and its ability to form stable 2D crystals have driven development of EC methods that are now being used to study... 

The use of techniques that focus on a subset of resonances make it possible to do productive NMR experiments on systems that do not have the narrowest possible linewidths, and thus to investigate more challenging proteins or to optimize sample conditions for a particular functional state rather than for the narrowest resonances. However, since the information content of the NMR experiment depends on the number of resolvable resonances, which depends on their linewidths, it is critical to seek conditions that minimize the linewidths while preserving functionality. The membrane protein system of interest will dictate which sample types are possible and which conditions preserve functionality Table 1 documents membrane protein linewidths that have been observed in a variety of sample types including nanocrystals, 2D crystals, detergent micelles, proteoliposomes and nanodisks. 

OmpG (outer membrane protein G)95 2D crystals 0.5-0.8 ppm 262-280 K (broader when frozen, 240 K) Broader in proteoliposomes... 

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