Maltose crystal structure

Diederichs, K, Diez, J., Greller, G., Muller, C., Breed, J., Schnell, C., Vonrhein, C., Boos, W. and Welte, W. (2000). Crystal structure of MalK, the ATPase subunit of the trehalose/maltose ABC transporter of the archaeon Thermococcus litoralis, EMBO J., 19, 5951-5961. 

Kobe B, Center RJ, Kemp BE, Poumbouris P. 1999. Crystal structure of human T cell leukemia virus type 1 gp21 ectodomain crystallized as a maltose binding protein chimera reveals structural evolution of retroviral transmembrane proteins. Proc Natl Acad Sci USA 96 4319-4324. 

For maltose. Figure 3 shows that there are no significant differences between the geometric results found with the four rather different potential energy functions. The only discrepancy is the absence of minimum 1 in the map of French (18). Most crystal structure data fall within the valley joining the three upper points. 

Duan, X.Q., Hall, J.A., Nikaido, H., Quiocho, F.A. (2001). Crystal structures of the malto-dextrin/maltose-binding protein complexed with reduced oligosaccharides flexibility of tertiary structure and ligand binding. Journal of Molecular Biology, 306, 1115-1126. 

Fig. 2.6 a, b. Hydrogen-bond connectivity diagram for maltose monohydrate, a Projection of a section of the crystal structure b schematic connectivity diagram... 

The cooperative, infinite chains and cycles formed by O-H 0 hydrogen bonds in the a-cyclodextrin hydrates are a characteristic structural motif [109]. As with the simpler carbohydrate crystal structures described in Part II, Chapter 13, the hydrogen bonds can be traced from donor to acceptor in the cyclodextrin hydrate crystal structures. Networks of O-H 0-H 0-H interactions are observed in which the distribution of hydrogen bonds follows patterns with two characteristic motifs. One are the "infinite chains which run through the whole crystal lattice, and the others are the loops or cyclically closed patterns (a special case of the "infinite chains). As in the small molecule hydrates, such as a-maltose monohydrate, the chains and cycles are interconnected at the water molecules to form the complex three-dimensional networks illustrated schematically in Fig. 18.5, with some sections shown in more detail in Fig. 18.7 a, b, c. 

Glycogenin and the mutant proteins, Phel94 and Thrl94, could also transfer glucose from UDP-Glc to maltose to form maltotriose." However, no further conversion to a higher oligosaccharide occurred. Analysis of the crystal structure by X-ray diffraction indicated that glycogenin existed similar to dimers." ... 

One observation raises the question of whether enough is known about the carbonium-ion lifetime in enzymic sites to be certain that it is always as short as estimated for reactions in water. The crystal structure of soybean beta-amylase complexed either with /8-maltose or maltal shows features strongly suggesting that the reaction center is shielded from solvent.101 A mechanism involving a carbonium-ion transition state with C-l unsubstituted and subject to attack by a structurally positioned water molecule, to form a product of /3-configurat.ion, is likely for the inverting reactions... 

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