Galactose epimerase

It is this transferase that is missing in galactosemia. UDP-galactose is normally transformed to UDP-glucose by UDP-galactose epimerase, and UDP-glucose may then form glycogen. 

Wyk, R, and Reeves, R. R. (1989). Identification and sequence of the gene for abequose synthase, which confers antigenic specificity on group B salmonellae Homology with galactose epimerase. J. Bacteriol. 171, 5687-5693. 

Finally, UDP-galactose is epimerized to UDP-glucose by the action of UDP-galactose epimerase (see Figure 12-6). This UDP-glucose can be used in the galactosyltransferase reaction. 

UDP-glucose-4-galactose epimerase (yeast, 10 U) no reported risk... 

Galactose epimerase deficiency see Inborn errors of metabolism. 

The metabolic interconversion of 2-deoxy-2-fluoro-D glucose and 2-deoxy-2-fluoro-D-mannose (and their 6-phosphates) in tumour cells was investigated by F - NMR spectroscopy, and a mannose glucose equilibrium ratio of -4 1 was observed.The conversion of 2-deoxy-2-fluoro-D-galactose into its aluco-isomer via the action of a UDP-galactose epimerase has been observed in vivo in mice by use of F - NMR spectroscopy ... 

Especially noteworthy is the use of sucrose, Glca(l-2)Fru, as the ultimate source of UDP-Gal. In a first step sucrose synthase from rice cleaves the disaccharide and forms UDP-Glc in the presence of UDP. UDP-Glc is subsequently epimerized at the 4-position by UDP galactose epimerase to give the required UDP-Gal. This donor substrate is first used by P(l-4)galactosyl transferase to produce the N-acetyllactosamine intermediate and then by a(l-3)galactosyl transferase to gal-... 

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