Magenta residues

Figure4.7 Crystallographic packing effects in factor Xa binding sites, shown for PDB structures lfax and lxkb. lfax is shown with white carbon atoms, the superimposed lxkb structure (rms deviation of binding site Ca atoms 0.38 A) is omitted. The ligand of lfax is shown in green and the ligand of lxkb in magenta. Residues present in the crystal packing environment of lxkb are shown in yellow.

Fig. 4.1. Topology, conservation, andRHPmotif oftheStel4poI5. cerevisiae. (A) Hydropathy plots predict six transmembrane segments (TMs). In this model, the N-and C-termini are disposed toward the cytosol. TM 5 and 6 are proposed to form a helix-turn-helix hehcal hairpin within the membrane [25]. Fifteen unique Icmt protein sequences were ahgned using ClustalW 2.0.1.1 [27]. The blue residues denote amino acid identity and the magenta residues denote amino acid similarity. The C-terminal portion of the enzyme (136-239) contains the majority of the identical amino acids. (B) Sequence of the RHP motif, a C-terminal consensus sequence common to Icmt enzymes, a number of bacterial open reading frames, and two phosphatidyl-ethanolamine methyltransferases. Numbers denote the amino acid position in Stel4p.

The violet dyestuffs of magenta residues differ from the indulines in so far that they give a brown solution with sulphmde acid, while all the latter give a blue. 

The reason for this is that there is no good method for production of phosphine, and as its preparation from magenta-residues is somewhat complieated, its price is relatively high. 

Fig. 2.8 Active site of NS3 protease with the inhibitor BILN 2061 added through molecular modelling [92], highlighting residues found to be mutated in resistance studies (Ala-156 and Asp-168, yellow Arg-155, green Gln-80, magenta).

The magenta color reaction for parathion has been adapted to mass-production techniques for quantitative estimation of parathion residues in and on certain fruits, vegetables, and miscellaneous substrates. 

The magenta color reaction for parathion has been adapted to mass-production techniques for quantitative estimation of parathion residues in and on certain fruits, vegetables, and miscellaneous substrates. From examination of the mechanisms of this color reaction, and from experiences gained in running nearly 3000 analyses on 50 different substrates, it has become apparent for such applications that ... 

Subsequent processing of the fruit components and extraction of the contained toxicants have been described (11, 12, 14, IS). Analyses for DDT residues have been made with the dehydrohalogenation method (11, 15). The magenta color reaction of Averell and Norris (1) as modified by Gunther and Blinn (H) was used to analyze for parathion residues. Appropriate fruit blanks were run with each set of analyses. 

Studies with parathion-treated citrus fruits have also shown no parathion to be present in the endocarpal, or pulp segment, portions of the fruit (Tables III, IV, and VI). Since the magenta color reaction for parathion is extremely sensitive, it is believed that even trace quantities are not present in the pulp. The rapidity of the subsurface penetration of parathion into the peel of citrus fruits and the persistence of these residues in the peel is demonstrated in Tables III through VII. 

Averell and Norris (3) have developed an analytical method adapted to the determination of parathion in spray or dust residues, which is sensitive to about 20 micrograms. It is based upon the reduction of parathion with zinc to the amino compound, diazotiza-tion, and coupling with Bratton and Marshall s amine, which gives an intense magenta color with an absorption peak at 555 millimicrons. Bowen and Edwards (6) have used the polarograph to assay technical grades of parathion and its formulations. 

Figure 3.2 Ribbon diagram of the C-lobe of human transferrin with the two domains shown in different colours (cyan for Cl and green for C2). The inset shows the four protein ligand residues together with the arginine residue which stabilizes binding of the synergistic carbonate ion (both in magenta). (Reprinted with permission from Mason et al., 2005. Copyright (2005) American Chemical Society.)...

The lines in blue show shifts at the active site residues while the imidazole signal is not shifted. The effects on the NMR signals in black (medium effects) and magenta (strong effects) are caused by changes in the pH (as indicated by the shifted imidazole line) induced by the ligands. 

Fig. 3.3. Structure of MPT synthase. (A) Overall structure of the heterotetramer. MoaD subunits are shown in yellow, MoaE subunits in cyan and magenta. The view is along the two-fold axis of symmetry. N- and C-termini and residues adjacent to a disordered loop...

A hexadentate chromium-complexed magenta dye (41) is described as being useful in image transfer applications.107 It is prepared by attaching an iminodiacetic acid residue to an o,o-dihydroxyazo dye in an appropriate position so that it is suitably disposed to coordinate to the chromium. 

Fig. 2. Structure of a heptahelical receptor. Cartoon model of dark (inactive) bovine rhodopsin (1U19), showing the seven transmembrane-spanning a helices (red to blue) and 11-r/Vi ctinal (gray spheres). Conserved residues important for receptor and G protein activation are shown (magenta spheres), including the DRY motif on helix III (yellow) and NpxxYx5F motif on helices VII and VIII blue and purple). The extracellular and intracellular faces of rhodopsin are shown. Receptor activation results in an outward movement of helix VI yellow arrow), which opens a gap in the cytoplasmic face of the receptor, exposing residues critical for G protein activation, such as the DRY motif on helix III (yellow).

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