A-D-Glucosamine-6-phosphate

Maley, G. F., and H. A. Lardy The synthesis of a-D-glucosamine-1-phosphate and N-acetyl-a-D-glucosamine-1-phosphate. Enzymatic formation of uridine diphosphogluco-samine. J. Amer. chem. Soc. 78, 5303 (1956). 

D-glucosamine 6-phosphate to D-glucosamine 1-phosphate. a-D-Glucose 1,6-diphosphate is a cofactor, 264(e)... 

This enzyme [EC 5.4.2.S], also known as acetylglucos-amine phosphomutase and A -acetylglucosamine-phos-phate mutase, catalyzes the interconversion of M-acetyl-D-glucosamine 1-phosphate and A -acetyl-o-glucosamine 6-phosphate. The enzyme is activated by A -acetyl-o-glu-cosamine 1,6-bisphosphate. 

It is not definitely known whether the a or the /3 anomer of AT-acetyl-n-glucosamine 1-phosphate is involved in this isomerization of A -acetyl-D-glucosamine 1-phosphate. However, an extremely acid-labile A -acetyl-n-glucosamine phosphate did contaminate some of the A -acetyl-... 

D-glucosamine preparation. This labile phosphate derivative is inactive as a substrate. Since the d anomer of D-glucosyl phosphate is more acid-labile than is the a anomer/ the a anomer of iV-acetyl-D-glucosamine 1-phosphate is considered to be involved in this reaction. ... 

A uridine pyrophosphate derivative of Ai -acetyl-n-glucosamine which contains an extra phosphate group has been isolated from a hot-water extract of hen oviducts. Uridine 5-phosphate and uridine 5-pyrophosphate have been recovered from acid hydrolyzates of this compound. A diphosphate ester of A-acetyl-n-glucosamine can also be obtained from acid hydrolyzates of this uridine compound. Because of the catalytic activity of phospho-A -acetyl-n-glucosamine mutase toward it, it is probably AT-ace-tyl-D-glucosamine 1,6-diphosphate. 

In the biosynthesis of A. s., the amino group is supplied by transamination from glutamine. Fructose 6-phosphate is aminated to D-glucosamine 6-phosphate by a hexose-phosphate transaminase. Glucosamine phosphate can then be converted by a transacetylase into the N-acetyl derivative. The latter is isomerized to the 1-phosphate, then activated by reaction with UTP, to form UDP-N-acetylglucosamine, which can be isomerized to UDP-N-acetylgalactosamine. See Muramic acid. Neuraminic acid. 

This enzyme [EC 2.7.1.63], also known as polyphosphate-glucose phosphotransferase, catalyzes the reaction of [phosphatejn with o-glucose to yield [phosphate] ( i) and D-glucose 6-phosphate. The enzyme requires the presence of a neutral salt (such as potassium chloride) for maximum activity. Glucosamine can also serve as a substrate. 

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