Sugars, translocation

Dutzler, R., et al. Crystal structures of various mal-tooligosaccharides bound to maltoporin reveal a specific sugar translocation pathway. Structure 4 127-134, 1996. 

Structural basis for sugar translocation through malto-porin channels at 3.1 A resolution. Science 267 512-514, 1995. 

Schirmer, T., T. A. Keller, Y.-F. Wang, and J. P. Rosenbusch. 1995. Structural basis for sugar translocation through maltoporin channels at 3.1 A resolution. Science 267 512-514. 

Perkins 10), as part of an extensive study on the chemistry of boron in plants, reported that the uptake of C-fructose, supplied exogenously to the petiole stump of excised trifoliate leaves of soybean plants, was markedly increased when 10 or 50 ppm of boron were supplied with the fructose. At comparable sections down the stem of the plants, the label was greater in the boron-supplied plants. However, the author stated that no conclusion about the eflFect of boron on increased translocation in plants was justified from his data. He speculated, however, that boron, with reasonable certainty, increased the uptake of sugars by plant cells but played only an indirect role in sugar translocation. 

The chemotactic receptors to glucose, fructose, mannose and certain other sugars are insensitive to osmotic shock (Table 4.1) and have been shown to be integral parts of the cytoplasmic membrane. These membrane-associated receptors have been shown to be identical with enzymes II, the substrate-specific components of phosphotransferase transport (the PEP system). The essential event during sugar translocation using the PEP system is the phosphoenolpyruvate-dependent phosphorylation of the... 

Semenza, G., 1976, Small intestinal disaccharidases Their properties and role as sugar translocators across natural and artificicd membranes, in The Enzymes of Biological Membranes, Vol. 3, Membrane Transport (A. Martonosi, ed.), pp. 349-382, Plenum Press, New York. 

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