PHOSPHATE BOUND TO HISTIDINE IN A PROTEIN AS AN INTERMEDIATE IN A NOVEL PHOSPHO-TRANSFERASE SYSTEM

作者：Werner Kundig, Sudhamoy Ghosh, Saul Roseman · 发表于：Proceedings of the National Academy of Sciences · 年份：1964 · DOI：10.1073/pnas.52.4.1067 · 被引用次数：613 · 研究领域：Chemical Reactions and Isotopes、Enzyme function and inhibition、Electrochemical sensors and biosensors

Mammalian tissues contain a kinase involved in the intermediary metabolism of the sialic acids.1' 2 This enzyme has been extensively purified,3 studied in detail, and catalyzes the following reaction: N-Acyl-D-mannosamine + ATP Mg++ N-Acyl-D-mannosamine-6-P + ADP.To determine whether this kinase occurred in bacteria, such as Aerobacter cloacae and Escherichia coli K235,4 that metabolize N-acetyl-D-mannosamine, extracts of these organisms were examined and found to contain a novel phospho-transferase system.The system obtained from E. coli K235 consisted of two enzymes, I and II, and a histidine-containing, heat- stable protein (HPr).The sequence of reactions is: I Phosphoenolypyruvate (PEP) + HPr Mg+ Phospho-histidine- protein (P-HPr) + Pyruvate (A) P-HPr + Hexose -., -Hexose-6-P + HPr (B)PEP + Hexose M Hexose-6-P + Pyruvate (A+B)The intermediate in the system, P-HPr, is protein-bound phosphohistidine.Materials and Methods.-Unlessotherwise specified, all materials were obtained from comi- mercial sources.Previously published methods', 6 were used for the preparation, separation, and characterization of C"1-and C'4-hexosamines, N-acylhexosamines, the corresponding 6-phosphate esters, and for the periodate oxidation of the esters and the characterization of glycolaldehyde- phosphate.The following compounds were prepared as described: P-histidine,6 N-phospho- glycine,7 phosphoramidate,8 and PEP."An essential substrate for these experiments, P32-PEP was prepared enzymatically by ...