Sugar Transport

作者：Werner Kundig, Saul Roseman · 发表于：Journal of Biological Chemistry · 年份：1971 · DOI：10.1016/s0021-9258(19)76986-5 · 被引用次数：217 · 研究领域：Amino Acid Enzymes and Metabolism、Polyamine Metabolism and Applications、Enzyme Structure and Function

Abstract A phosphotransferase system was isolated from Escherichia coli and was detected in other gram-negative organisms. The system catalyzed the transfer of phosphate from phosphoenolpyruvate to sugars of the d-gluco and d-manno configurations, yielding pyruvate and the corresponding sugar 6-phosphate esters. Fractionation of the enzyme system yielded three protein components, Enzymes I and II, and a histidine-containing protein, designated HPr. Enzyme I catalyzed the transfer of phosphate from phosphoenolpyruvate to HPr. The phosphoryl moiety in phospho-HPr was linked to the protein via an imidazole nitrogen atom of a histidine residue. Enzyme II catalyzed the transfer of phosphate from phospho-HPr to the sugars. Enzyme I and HPr were soluble constituents of the cell, while Enzyme II (or Fraction II) was located in the membrane fraction.