A-D-Galactose-l-phosphate

Fig. 14. Salvage pathways of nucleotide sugars. L-fucose (11), (3-L-fucose-l-phosphate (12), GDP-p-L-fucose (13), A fucokinase (EC 2.7.1.52), B GDP-Fuc pyrophosphorylase (EC 2.7.7.30). D-galactose (14), a-D-galactose-l-phosphate (15), UDP-a-D-galactose (16), C galactokinase (EC 2.7.1.6), D UDP-Gal pyrophosphorylase. IV-acetyl-D-galactosamine (17), Al-acetyl-a-D-galactosamine-l-phosphate (18), UDP-lV-acetyl-a-D-galactosamine (19), E IV-acetyl-galactosamine kinase (EC 2.7.1. ), F UDP-GalNAc pyrophosphorylase (EC 2.7.7. )...

D-Galactose phenylosotriazole, III, 38 a-D-Galactose 1-phosphate, V, 71 D-Galactose sulfates, II, 178 aldehydo-D-Galactose, l-chloro-l-thio-ethoxy-, pentaacetate, I, 96 aMelij/do-D-Galactose, l-thioethoxy-3,4,-6,6-tetraacetyI-, ethyl 1,2-orthoacetate, I, 96, 121... 

Aldoses react with ATP in a phosphotransferase-catalyzed reaction (C 1.1) either to sugar-l-phosphates, e.g., D-galactose-l-phosphate and L-arabinose-1-phosphate, or to sugar-co-phosphates, e.g., D-glucose-6-phosphate (Fig. 27), D-mannose-6-phosphate, D-galactose-6-phosphate, and D-ribose-5-phosphate. Aldose-l-phosphates may also be formed from co-phosphates by mutases (Fig. 27) with 1,co-diphosphates as intermediates. 

Phosphorylase is specific with regard to its action upon < -D-glucose-l-phosphate the / -isomer cannot serve as a substrate for this enzyme. Neither can any other sugar ester be substituted for glucose-l-phosphate. a-L-Glucose-l-phosphate, maltose-l-phosphate, a-D-xylose-l-phosphate could not be polymerized to polysaccharide by potato phosphorylase. - The a-forms of D-mannose-l-phosphate and D-galactose-l-phosphate were not acted upon by muscle phosphorylase. ... 

Enzymatic syntheses.—Labeled compounds. A mixture of 140 /mmoles of galactose-1- C, 240 /mmoles of adenosine triphosphate, MgClg, and K-phosphate buffer adjusted with 2 N KOH to pH 7, galactokinase preparation added, incubated 1 hr. at 30°, then heated 1 min. in a boiling water bath crude a-D-galactose-l- G 1-phosphate. Y 95% as the Ba-salt. Also syntheses of nucleotides s. E. P. Anderson, E. S. Maxwell, and R. M. Burton, Am. Soc. 81, 6514 (1959). 

Fig. 4. Discriminatory power of the various methods of estimating erythrocytic galactose-l-phosphate uridyl transferase. Methods (a) Anderson et al. (A2) (b) Bretthauer et al. (B17) (c) Kirkman and Bynum (KLO), and Hsia et al. (H12) and (d) Schwarz et al. (S12).

Fermentation procedures useful for the production of uridine 5 -(a-D-galactopyranosyl pyrophosphate) involve the cultivation of bacterial mutant-strains that are deficient in the 4"-epimerase for 30 (see Section V,l,b, p. 369) in D-galactose-containing media,245-247 or by incubating Torulopsis Candida cells with uridine 5 -phosphate, D-galactose, potassium phosphate, and magnesium sulfate.248... 

Every new charge of DEAE cellulose ( form) should be tested. Dry 10 d each of 14C-galactose and 14C-galactose-l-phosphate with nitrogen and dissolve in 300 pi H20, each. Put 100 pi of each into a counter vial containing 15 ml of OptiPhase (= 100%), 100 pi of each onto columns with 1 ml DEAE cellulose, and 100 pi of both onto a third column (mix). 

Pyranose-/orm 1-Dihydrogen phosphate, G-420 a-D-Glucopyranosyl-(l 4)-[a-D-mannopyranosyl-(l ->3)]-D-galactose ... 

Similar reactions have recently been found in plants to be involved in pentose metabolism.D-Xylose-l-phosphate was found to react with UTP to form UDPXy. A second enzyme, which may be different from the epimerase of glucose-galactose interconversions, epimerizes carbon 4 of the pentose to produce the UDP derivative of L-arabinose. The number of specific pyrophosphorylases for sugar phosphates in plant tissue is not known at this time. 

Free Supars and Simple Derivatives thereof.- a-D-Glucopyranose. (NaCl)o hydrate, 1,2,3-tri-0-acetyl-j9-L-rhamnopyranose, D-galactose 1-phosphate dipotassium salt, D-glucose 6-phosphate bis(cyclohexylammonium) salt, amiprilose [3-0-(3-dimethylaminopropyl)-l,2-0-isopropylidene-a-D-glucofuranose]hydrochloride, 2,3 4,5-di-O-isopropylidene-l-O-methyl- -D-fructopyranose, and the 3,5,6-bicyclothiono- and seleno-phosphates of 1,2-0-isopropylidene-o-D-glucofuremose. ... 

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