Zinc gray

Figure 35 Comparison between the ligand-binding site (stereoview) of (a) the transient penta-coordinated cadmium (green)-substituted LADH in ternary complex with the inhibitor DMSO (131) (orange) and NADH (pink) (PDB ID 2JHF), showing coordination with OH" ion (yellow) derived from a water molecule and (b) tetrahedrally coordinated zinc (gray) in liver sorbitol dehydrogenase ternary complex with the inhibitor IBA (132) (green) and NADH (pink) (PDB ID 2JHG).

Zinc gray Zinc dust used as a pigment. 

Zinc oxide. Red atoms are oxygen and turquoise atoms are zinc. Gray sticks indicate double bonds, publishers... 

The fumes of zinc chloride are highly toxic and can damage mucous membranes and cause pale gray cyanation. It can also ulcerate the skin of workers using it as a soldering flux or those handling wood impregnated with it (59). 

Figure 17.8 Catal3ftic zinc center of horse liver alcohol dehydrogenase revealed from an X-ray crystallographic structure (PDB file 20HX) [Al-Karadaghi et al., 1994]. The bound NADH cofactor, a molecule of the inhibitor dimethylsulfoxide (DMSO), and the amino acid residues that coordinate the Zn are shown as sticks shaded according to the elements, and the Zn center is shown as a gray sphere, while the protein is shown in thin gray lines.

Phthalic anhydride condenses with the aniline derivative in the presence of zinc or aluminum chlorides to yield the intermediate benzoyl-benzoic acid, which subsequently reacts with l,3-bis-V,V-dimethylaniline in acetic anhydride to yield the phthalide. The above compound gives a violet-gray image when applied to a clay developer. Clearly this synthesis is also very flexible and variations in shades of color formers have been obtained by varying the aniline components and also by using phthalic anhydrides substituted, for example, by nitro groups or chlorine atoms. Such products have excellent properties as color formers and have been used commercially. Furthermore, this synthetic route is of great importance for the preparation of heterocyclic substituted phthalides, as will be seen later. 

Fig. 9.1. Left panel A model zinc finger obtained using the second domain of the transcription factor IIIA. The zinc ion (gray sphere) is coordinated tetrahedrally by two histidine (H) and two cysteine (C) residues. Right panel Results showing the free energy change for displacing Zn2+ by other comparable ions Fe2+ and Co2+ from different binding motifs CCHH, CCHC, and CCCC, respectively...

C.S. StClair, H.B. Gray, and J.S. Valentine, Spectroelectrochemistry of copper-zinc superoxide dismutase. Inorg. Chem. 31, 925-927 (1992). 

Physical properties zinc metal is a gray and shiny solid... 

Donker, M.H., H.M. Abdel-Lateif, M.A. Khalil, B.M. Bayoumi, and N.M. Van Straalen. 1998. Temperature, physiological time, and zinc toxicity in the isopod Porcellio scaber. Environ. Toxicol. Chem. 17 1558-1563. Droual, R., C.U. Meteyer, and F.D. Galey. 1991. Zinc toxicosis due to ingestion of a penny in a gray-headed chachalaca (Ortalis cinereiceps). Avian Dis. 35 1007-1011. 

Fig. 6. Structure of the T4 short tail fiber. The structure of residues 246-527 is shown it is a composite of two partial structures (Thomassen et al., 2003 van Raaij et al., 2001a). The different domains are indicated the T4-fiber fold consisting of residues 246-286, the triple / -helix (residues 290-329), the collar domain (residues 330-396 and 518-527), and the receptor-binding domain (amino acids 397-517). The zinc ion in the center of the receptor-binding domain is shown as a gray sphere.

Zinc dust (Zn) is not a compound but a gray powder that is used as a pigment and acts as an excellent reducing agent and catalyst. It is dangerous because it can explode when exposed to moist air and may heat up and ignite spontaneously. When mixed with dry, powdered sulfur, it makes an excellent dry propellant-type rocket fuel, but is dangerous to handle. 

The secondary structure of the proteins are shown as dark gray helices and the beta strands and coil regions are in light gray. The zinc ions are shown as spheres, (b) The NAD molecule bound to the enzyme and the acetylated peptide of p53 are shown as ball and sticks. The acetylated lysine is labeled. 

Zinc sulfide is white to gray-white or pale yellow powder. It exists in two crystalline forms, an alpha (wurtzite) and a beta (sphalerite). The wurtzite form has hexagonal crystal structure refractive index 2.356 density 3.98 g/cm3 melts at 1,700°C practically insoluble in water, about 6.9 mg/L insoluble in alkalis soluble in mineral acids. The sphalerite form arranges in cubic crystalline state refractive index 2.368 density 4.102 g/cm changes to alpha form at 1,020°C practically insoluble in water, 6.5 mg/L soluble in mineral... 

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