Interaction diagram, specific groups

Hydrogen bonding in Continued) Interaction diagram, specific groups... 

We now proceed to the next case in which the substituents consist of a donor and acceptor. The specific molecule will be 1,2-difluoro-dicyanoethylene. Following the previous procedure, the group MO s of the substituents and the ethylene -n and 7r MO s are used to construct the MO s of the composite system. The interaction diagrams are shown in Fig. 25. The results are analogous to the previous example except for the additional stabilizing interactions which will also favor the cis isomer. Consequently, the cis isomer is expected to be the most stable isomer. 

Figure 9.10 Schematic diagrams illustrating the complex between DNA (orange) and one monomer of the homeodomain. The recognition helix (red) binds in the major groove of DNA and provides the sequence-specific interactions with bases in the DNA. The N-terminus (green) binds in the minor groove on the opposite side of the DNA molecule and arginine side chains make nonspecific interactions with the phosphate groups of the DNA. (Adapted from C.R. Kissinger et al Cell 63 579-590, 1990.)...

Fig. 1.34 Activators and coactivators of transcription intiation. The figure shows the function of three groups of proteins that function as coactivators. The general cofactors mediate the interactions between the specific transcription activators and the TFIID complex as well as with various forms of the RNA polymerase II holoenzyme. The TAFs are components of the TFIID complex and serve as contact points for specific transcription activators. The mediators are components of various forms of holoenzymes of RNA polymerase II. SRB proteins belong to the class of mediators, which, among other things, interacts with the CTD of RNA polymerase. The simphfied diagram does not show the interactions with chromatin.

Figure 6 Schematic diagram of the active site of the E. coli NADP-IDH with bound 2A,3>S-isocitrate (A) and the active site of T. thermophilus NAD-IMDH with bound 2R,3S-isopropylmalate (B). A prime indicates the residues donated from the second subunit, a, 3 refers to a- and P-carboxyl groups, respectively. The major determinants of substrate specificity are residues Seri 13 and Asnll5 in the NADP-IDH, and Glu87 and Leu90 in the NAD-IMDH, which interact with the unique y-moieties of the substrates. (Modified from Ref. 15.)...

A Fourier transform infrared spectrometer can be used to detect functional groups. This technique indirectly detects the miscibility by investigating some types of specific interactions in the blends, e.g. hydrogen bonding. Knowing about these molecular interactions can then be used to explain the shape of the phase diagrams. It is apparent that, in reality, there is no perfect technique to study all systems. The characteristics of different systems, the time available, operating costs, and the limitations of equipment need to be taken into consideration." ... 

Information on the interaction of europium and platinum with germanium is due to the work of two research groups who employed X-ray powder as well as single-crystal analyses for the investigation of alloys with specific compositions. The phase diagram of the Eu-Pt-Ge system is not available. 

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