The Leloir pathway: a mechanistic imperative for three enzymes to change the stereochemical configuration of a single carbon in galactose

@article{Frey1996TheLP,
  title={The Leloir pathway: a mechanistic imperative for three enzymes to change the stereochemical configuration of a single carbon in galactose},
  author={Perry Allen Frey},
  journal={The FASEB Journal},
  year={1996},
  volume={10},
  pages={461 - 470}
}
  • P. Frey
  • Published 1 March 1996
  • Biology, Chemistry
  • The FASEB Journal
ABSTRACT: The biological interconversion of galactose and glucose takes place only by way of the Leloir pathway and requires the three enzymes galactoki‐ nase, galactose‐1‐P uridylyltransferase, and UDP‐ galactose 4‐epimerase. The only biological importance of these enzymes appears to be to provide for the interconversion of galactosyl and glucosyl groups. Galactose mutarotase also participates by producing the galactokinase substrate α‐D‐galactose from its β‐anomer. The galacto/gluco… 

Structure and Function of Enzymes of the Leloir Pathway for Galactose Metabolism*

Recent advances in the understanding of the structure and function of the Leloir pathway are presented, highlighting their important metabolic role in normal galactose metabolism.

Sugar recognition by human galactokinase

The sugar specificity of the enzyme and the kinetic consequences of mutating residues in the sugar-binding site are investigated in order to improve the understanding of substrate recognition by this enzyme.

Identification of a mutarotase gene involved in D‐galactose utilization in Aspergillus nidulans

It is concluded that GalmB is the physiologically relevant mutarotase for the utilization of D‐galactose in A. nidulans.

UDP‐galactose 4‐epimerase from Kluyveromyces  fragilis – catalytic sites of the homodimeric enzyme are functional and regulated

Dissimilar kinetic patterns of the reconstituted enzyme after treatment with p‐chloromercuribenzoate indicated stability of the dimeric enzyme against fast association–dissociation, which could otherwise generate multiple forms of the enzyme with functional heterogeneity.

Structural basis for the reaction mechanism of UDP-glucose pyrophosphorylase

Isothermal titration calorimetry analyses demonstrated that Mg2+ ion plays a key role in the enzymatic activity of UGPase by enhancing the binding of U GPase to UTP or UDP-glucose, suggesting that this reaction is catalyzed by an ordered sequential Bi Bi mechanism.

Galactose metabolism in yeast-structure and regulation of the leloir pathway enzymes and the genes encoding them.

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