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. 1971 Nov;68(11):2660–2663. doi: 10.1073/pnas.68.11.2660

Uridine Diphosphate-4-Keto-Glucose, an Intermediate in the Uridine Diphosphate-Galactose-4-Epimerase Reaction

Utpalendu S Maitra 1, Helmut Ankel 1
PMCID: PMC389495  PMID: 4941982

Abstract

When UDP-galactose 4-epimerase (EC 5.1.3.2) from Escherichia coli is incubated with UDP-galactose, then reduced with NaB3H4, label is found in UDP-glucose and UDP-galactose. Enzymatic and chemical degradation demonstrates that the label is bound to carbon 4 of the glycosyl moieties. These results provide direct evidence for the existence of UDP-4-keto-glucose as an enzyme-bound intermediate in the epimerization reaction, and they exclude the formation of a 3-keto intermediate.

Keywords: E. coli, epimerase, enzyme-substrate complex, reduction, chemical and enzymatic degradation

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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