Trisaccharides crystal structures

In di- and trisaccharide crystal structures and in cyclodextrins, intramolecular hydrogen bonds have been observed between adjacent monosaccharides, as shown by the representative examples given in Thble 9.3 and shown in Fig. 9.1. If these... 

F. Alberto, E. Jordi, B. Henrissat, and M. Czjzek, Crystal structure of inactivated Thermotoga maritima invertase in complex with the trisaccharide substrate raffinose, Biochem. J., 395 (2006) 4574-62. 

The abnormal case is sucrose. Apparently the geometry of the molecule as observed in the crystal structure places constraints on the rotations which are not found in the sucrose moiety of the three trisaccharides. These constraints arise from the positions of the hydrogen atoms involved in the two intramolecular H-bonds, which are present in... 

For the carbohydrates especially, the amount of available crystal structural data decreases sharply with molecular complexity [479]. With the exception of the cyclodextrins, discussed in Part III, Chapter 18, there are less than 40 crystal structure analyses of oligosaccharides, of which less than 10 are trisaccharides, one is a tetrasaccharide, and one a hexasaccharide (Part III, Chap. 18). The majority of the basic monosaccharides that are the subunits of the polysaccharides that occur naturally have been studied for example, the pyranose forms of /7-arabinose, a-xylose, a- and -glucose, / fructose, a-sorbose, a-mannose, a- and -galactose, a-fucose, a-rhamnose, N-acetyl glucosamine, and mannosamine (Box 13.2). How-... 

Hydrogen-bonding patterns in crystal structures of the cydodextrins and the simpler carbohydrates differ. The infinite, homodromic chains are common both in the low molecular-weight carbohydrates and in the cydodextrins. The principal difference lies in the frequency of occurrence of the homodromic and antidromic cycles, which are common in the cyclodextrin crystal structures and rare in the mono-, di-, and trisaccharides. The cyclic patterns are the rule in the clathrate hydrates and in the ices. From this point of view, the hydrogen-bonding patterns of the hydrated cydodextrins lie between those of the simpler hydrated carbohydrates and those of the hydrate inclusion compounds, discussed in Part IV, Chapter 21. 

YveUn F, Zhang Y-M, Mallet J-M, Robert F, Jeannin Y, Sinay P. Crystal structure of the Lewis x trisaccharide. Carbohydr. Lett. 

A peculiar sugar modification occurs in the biosynthesis of the aclacino-mycins. These anthracyclines contain a trisaccharide moiety attached to the aklavinone scaffold at the C-7 position (Scheme 1). The first two carbohydrates in the aclacinomycins are rhodosamine and 2-deoxyfucose, but they differ structurally in their third sugar component, which is rhodinose in AclN, cinerulose A in AclA, L-aculose in AclY and cinerulose B in AclB [157]. The conversion of rhodinose to L-aculose is catalysed in a two-step process by the FAD-dependent enzyme aclacinomycin oxidoreductase [71] (Scheme 5, step 31). The three-dimensional structure of this oxidase revealed that the cofactor FAD is bound via two covalent bonds to the enzyme. Crystal structure and functional data further established a mechanism where the two different reactions are catalysed in the same active site of the enzyme but by different active site residues [71]. 

D. R. Bundle, H. Baumann, J.-R. Brisson, S. M. Gagne, A. Zdanov, and M. Cygler, Biochemistry, 33, 5183 (1993). Solution Structure of a Trisaccharide-Antibody Complex Comparison of NMR Measurements with a Crystal Structure. 

Table 1. Crystal structures of trisaccharides and tetrasaccharides. Trisaccharide...

Figure 4. The molecular and crystal structure of Lewis X [291- Graphical representation of the two trisaccharides constituting the asymmetric unit along with the water molecules hydrating them. Nine of the water molecules are part of the asymmetric unit content and the other ones are related by symmetry element.

The presence of the pyranose ring in the two D-glucose units of melezitose was inferred by Zempl6n and Braun from good evidence, and made certain by Miss Leitch29 through the crystallization of the requisite amount of 2,3,4,6-tetramethyl-D-glucose from the scission products of the fully methylated trisaccharide. The revised interpretation of Miss Leitch s experimental data concerns only the structure of the... 

B, Imberty A. Crystal and molecular structure of a histo-blood group antigen involved in cell adhesion the Lewis x trisaccharide. Glycobiology 1996 6 537-542. 46. 

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