Glycogen contains phosphodiester groups that can be introduced by UDPglucose:glycogen glucose 1‐phosphotransferase

FEBS Letters

Marchase, Richard B.¹  Lomako, Wieslawa M.²  Lomako, Joseph²  Whelan, William J.² 

[1] Department of Cell Biology, University of Alabama at Birmingham, Birmingham, AL 35294, USA;Department of Biochemistry and Molecular Biology, University of Miami, Miami, FL 33101, USA

关键词: Glycogen;    Glycogen phosphodiester;    Glucose 1-phosphate transferase;   

DOI  :  10.1016/0014-5793(93)80234-L

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Rabbit-muscle glycogen contains covalently bound phosphorus, equivalent to 1 phosphate group per 208 glucose residues. This often disputed, minor component was previously thought to represent a phosphomonoester group at C-6 of a glucose residue. Here we show that more than half the phosphorus is present as a phosphodiester, the remainder being monoester. A novel enzyme activity has been found in muscle that can account for the presence of the phosphodiester in glycogen. This is a UDPglucose:glycogen glucose 1 -phosphotransferase that positions glucose 1 -phosphate on C-6 of glucose residues in glycogen, forming a diester. The phosphomonoester groups present may arise by removal of the glucose residue originally transferred as glucose 1-phosphate.

【 授权许可】

Unknown