Given that galactose is metabolized by a pathway that includes the isomerization of UDP-galactose to UDP-glucose where UDP is uridylyl diphosphate. NAD + is used as cofactor by the enzyme responsible for the transformation. A mechanism for this transformation is to be proposed. Concept introduction: UDP-Galactose has an axial –OH on C 4 while UDP-glucose has it in equatorial position. The isomerization of UDP-galactose to UDP-glucose can be brought about by oxidizing the -OH on C 4 in to a ketone and then reducing the ketone back into the alcohol. To propose: A mechanism for the isomerization of UDP-galactose to UDP-glucose where UDP is uridylyl diphosphate. The enzyme responsible for the transformation uses NAD + as cofactor.

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Chapter 17.SE, Problem 73AP

Interpretation Introduction

Interpretation:

Given that galactose is metabolized by a pathway that includes the isomerization of UDP-galactose to UDP-glucose where UDP is uridylyl diphosphate. NAD⁺ is used as cofactor by the enzyme responsible for the transformation. A mechanism for this transformation is to be proposed.

Concept introduction:

UDP-Galactose has an axial –OH on C₄ while UDP-glucose has it in equatorial position. The isomerization of UDP-galactose to UDP-glucose can be brought about by oxidizing the -OH on C₄ in to a ketone and then reducing the ketone back into the alcohol.

To propose:

A mechanism for the isomerization of UDP-galactose to UDP-glucose where UDP is uridylyl diphosphate. The enzyme responsible for the transformation uses NAD⁺ as cofactor.

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