Galactose transport

Glucose/galactose malabsotption (GGM) is an intestinal monosaccharide (glucose and galactose) transport deficiency. The disorder manifests itself within the first weeks of life. The severe diarrhea and dehydration are usually fatal unless glucose and galactose are eliminated from the diet. Fiuctose and xylose are absorbed normally. Occurrence in both males and females, familial incidence, in particular in parental consanguinity, indicate autosomal recessive inheritance of... 

A Smulders, EM Wright. (1971). Galactose transport across the hamster small intestine The effect of sodium electrochemical gradients. J Physiol 212 277-286. 

Horak J, Wolf DH (1997) Catabolite inactivation of the galactose transporter in the yeast Saccharomyces cerevisiae Ubiquitination, endocytosis and degradation in the vaccuole. J Bacteriol 179 1541-1549... 

Thompson, J. 1978. In vivo regulation of glycolysis and characterization of suger phos-photransferase systems in Streptococcus lactis. J. Bacteriol 136, 465-476. Thompson, J. 1980. Galactose transport systems in Streptococcus lactis. J. Bacteriol 144, 683-691. 

Figure 8. Galactose transport by kidney slices from adult vs. newborn...

Studies on intestinal absorption were carried out in vivo (102). It was found that in contrast to the situation in kidney the galactose transport mechanism was well developed in the small intestine of newborn... 

Glucose and galactose transport in cestodes appears to occur via a common carrier system, as these sugars are mutually competitive inhibitors. This uptake mechanism is potassium and phlorizin sensitive and sodium... 

Erickson JD, Eiden LE, Hoffman BJ (1992) Expression cloning of a reserpine-sensitive vesicular monoamine transporter. Proc Natl Acad Sci USA 89 10993-10997 Erickson JD, Schafer MK, Bonner TI, Eiden LE, Weihe E (1996) Distinct pharmacological properties and distribution in neurons and endocrine cells of two isoforms of the human vesicular monoamine transporter. Proc Natl Acad Sci USA 93 5166-5171 Faham S, Watanabe A, Besserer GM, Cascio D, Specht A, Hirayama BA, Wright EM, Abramson J (2008) The crystal structure of a sodium galactose transporter reveals mechanistic insights into Na+/sugar symport. Science 321 810-814... 

Schematic representation of glucose (or galactose) transport by the enterocyte. Glucose binds to the receptor, facilitated by the simultaneous binding of two Na+ at separate sites. The glucose and Na" " are released in the cytosol as the receptor affinity for them decreases. The Na" " are actively extruded at the basolateral surface into the intercellular space by Na+,K+-ATPase, which provides the energy for the overall transport. Glucose is transported out of the cell into the intercellular space and thence to portal capillaries, both by a serosal carrier and by diffusion. (Reproduced with permission from G. M. Gray, Carbohydrate Absorption and Malabsorption in Gastrointestinal Physiology. Raven Press,...

Fructose transport is distinct from glucose-galactose transport and requires a specific saturable membrane carrier (facilitated diffusion). 

SLC35 (3) SLC37 (1) CMP-sialic acid and UDP-galactose transporter Glycerol-3-phosphate transporter CST, UGALT Ubiquitous... 

Silhavy, T. j.. Boos, W. and Kalckar, H. M. (1975) The role of the Escherichia coli galactose-binding protein in galactose transport and chemotaxis. Biochemistry of Sensory Functions (L. Jaenicke, ed.), pp. 1-30, Springer-Verlag, Berlin. 

Tabuchi M, Tanaka N, Iwahara S, Takegawa K. The Schizosaccharomyces pombe gmsl + gene encodes an UDP-galactose transporter homologue required for protein galactosylation. Biochem. Biophys. Res. Commun. 1997 252 121 125. 

Ishida N, Miura N, Yoshioka S, Kawakita M. Molecular cloning and characterization of a novel isoform of the human UDP-galactose transporter, and of related complementary DNAs belonging to the nucleotide-sugar transporter gene family. J. Biochem. (Tokyo) 1996 20 1074-1078. 

Yoshioka S, Sun-Wada GH, Ishida N, Kawakita M. Expression of the human UDP-galactose transporter in the Golgi membranes of murine Had-1 cells that lack the endogenous transporter. J. Biochem. (Tokyo) 1997 /22 691-695. 

Ishida N, Yoshioka S, lida M, Sudo K, Miura N, Aoki K, Kawakita M. Indispensability of transmembrane domains of Golgi UDP-Galactose transporter as revealed by analysis of genetic defects in UDP-Galactose transporter-deficient murine Had-I mutant cell lines and construction of deletion mutants. J. Biochem. (Tokyo) 1999 726 1107-1117. 

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