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The concerted inactivation of Escherichia coli uridine diphosphate galactose 4-epimerase by sugar nucleotide together with a free sugar.

ABSTRACT: 1. The combined effect of the sugar nucleotides UDP-D-fucose or UDP-D-glucuronic acid together with the free sugars D-fucose or L-arabinose is the inactivation of the Escherichia coli enzyme UDP-galactose 4-epimerase (EC 5.1.3.2). The sugar nucleotide or the free sugar alone or the sugar nucleotide plus 5'-Ump do not inactivate the enzyme. 2. The inactivation of the enzyme by its substrate UDP-D-glucose was not affected by the presence of free sugar. 3. In all cases the inactivation observed follows pseudo-first-order kinetics. 4. A comparison of various sugar nucleotides indicates that the hydroxymethyl group at position 6 of the sugar moiety of the natural substrates is important for substrate binding.

SUBMITTER: Blackburn P

PROVIDER: S-EPMC1172827 | biostudies-literature | 1976 May

REPOSITORIES: biostudies-literature

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The concerted inactivation of Escherichia coli uridine diphosphate galactose 4-epimerase by sugar nucleotide together with a free sugar.

Blackburn P P Ferdinand W W

The Biochemical journal 19760501 2

1. The combined effect of the sugar nucleotides UDP-D-fucose or UDP-D-glucuronic acid together with the free sugars D-fucose or L-arabinose is the inactivation of the Escherichia coli enzyme UDP-galactose 4-epimerase (EC 5.1.3.2). The sugar nucleotide or the free sugar alone or the sugar nucleotide plus 5'-Ump do not inactivate the enzyme. 2. The inactivation of the enzyme by its substrate UDP-D-glucose was not affected by the presence of free sugar. 3. In all cases the inactivation observed fol ...[more]

PMID: 779771

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