title: The metabolism of d-galactosamine and N-acetyl-d-galactosamine in rat liver.
abstract: d-[1-(14)C]Galactosamine appears to be utilized mainly by the pathway of galactose metabolism in rat liver, as evidenced by the products isolated from the acid-soluble fraction of perfused rat liver. These products were eluted in the following order from a Dowex 1 (formate form) column and were characterized as galactosamine 1-phosphate, sialic acid, UDP-glucosamine, UDP-galactosamine, N-acetylgalactosamine 1-phosphate, N-acetylglucosamine 6-phosphate, UDP-N-acetylglucosamine, UDP-N-acetylgalactosamine and an unidentified galactosamine-containing compound. In addition, [1-(14)C]glucosamine was found in the glycogen, an incorporation previously shown to result from the substitution of UDP-glucosamine for UDP-glucose in the glycogen synthetase reaction. Analysis of the [1-(14)C]glucosamine-containing disaccharides released from glycogen by beta-amylase provided additional evidence that they consist of a mixture of glucose and glucosamine in a 1:1 ratio, but with glucose predominating on the reducing end. UDP-N-acetylgalactosamine was shown to result from the reaction of UTP with N-acetylgalactosamine 1-phosphate in the presence of a rat liver extract.
authors.affiliation: Division of Laboratories and Research, New York State Department of Health, Albany, N.Y. 12201, U.S.A.
authors.forename: F
authors.initials: F
authors.lastname: Maley
authors.forename: A L
authors.initials: AL
authors.lastname: Tarentino
authors.forename: J F
authors.initials: JF
authors.lastname: McGarrahan
authors.forename: R
authors.initials: R
authors.lastname: Delgiacco