Specificity sugar moiety

Figure 17.3 Anatomy of a redox enzyme representation of the X-ray crystallographic structure of Trametes versicolor laccase III (PDB file IKYA) [Bertrand et al., 2002]. The protein is represented in green lines and the Cu atoms are shown as gold spheres. Sugar moieties attached to the surface of the protein are shown in red. A molecule of 2,5-xyhdine that co-crystallized with the protein (shown in stick form in elemental colors) is thought to occupy the broad-specificity hydrophobic binding pocket where organic substrates ate oxidized by the enzyme. Electrons from substrate oxidation are passed to the mononuclear blue Cu center and then to the trinuclear Cu active site where O2 is reduced to H2O. (See color insert.)...

In the previous chapters it has been shown that stable cell membrane models can be realized via polymerization of appropriate lipids in planar monolayers at the gas-water interface as well as in spherical vesicles. Moreover, initial experiments demonstrate that polymeric liposomes carrying sugar moieties on their surface can be recognized by lectins, which is a first approach for a successful targeting of stabilized vesicles being one of the preconditions of their use as specific drug carriers in vivo. 

DNA-TopI-rebeccamycin crystal ternary structure has proven the mechanism of action, showed binding specificity with enzyme, with maleimido and the sugar moiety affinity for interacting with the topi enzyme, while the indolocarbazole moiety intercalates into the DNA base pairs to form covalent interactions [16],... 

Some membrane proteins are covalently linked to complex arrays of carbohydrate. For example, in gly-cophorin, a glycoprotein of the erythrocyte plasma membrane, 60% of the mass consists of complex oligosaccharide units covalently attached to specific amino acid residues. Ser, Thr, and Asn residues are the most common points of attachment (see Fig. 7-31). At the other end of the scale is rhodopsin of the rod cell plasma membrane, which contains just one hexasac-charide. The sugar moieties of surface glycoproteins influence the folding of the proteins, as well as their sta-... 

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