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

  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},
  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.

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The molecular structure of UDP‐galactose 4‐epimerase from Escherichia coli determined at 2.5 Å resolution

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Galactose-1-phosphate uridylyltransferase: isolation and properties of a uridylyl-enzyme intermediate.

It is concluded that the uridylyl-enzyme contains at least one essential sulfhydryl group which is not located in the active site in such a way as to be shielded by substrates.

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Galactose-1-phosphate uridylyltransferase. Purification of the enzyme and stereochemical course of each step of the double-displacement mechanism.

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The pathway of the adaptive fermentation of galactose by yeast.

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