The Phosphoglycerate Mutases

The putative tumor metastasis suppressor protein Nm23-H1 is a nucleoside diphosphate kinase that exhibits a novel protein kinase activity when bound to glyceraldehyde-3-phosphate dehydrogenase (GAPDH). In this study we show that the glycolytic enzyme phosphoglycerate mutase B (PGM) becomes phosphorylated in the presence of the Nm23-H1⅐GAPDH complex in vitro. Mutation of His-10 in PGM abolishes the Nm23-H1⅐GAPDH complex-induced phosphorylation. Nm23-H1, GAPDH, and PGM are known to co-localize as shown by free flow isoelectric focusing. In association with Nm23-H1 and GAPDH, PGM could be activated by dCTP, which is a substrate of Nm23-H1, in addition to the well known PGM activator 2,3-bisphosphoglycerate. A synthetic cell-penetrating peptide (PGMtide) encompassing the phosphorylated histidine and several residues from PGM (LIRHGE) promoted growth arrest of several tumor cell lines, whereas proliferation of tested non-tumor cells was not influenced. Analysis of metabolic activity of one of the tumor cell lines, MCF-7, indicated that PGMtide inhibited glycolytic flux, consistent with in vivo inhibition of PGM. The specificity of the observed effect was further determined experimentally by testing the effect of PGMtide on cells growing in the presence of pyruvate, which helps to compensate PGM inhibition in the glycolytic pathway. Thus, growth of MCF-7 cells was not arrested by PGMtide in the presence of pyruvate. The data presented here provide evidence that inhibition of PGM activity can be achieved by exogenous addition of a polypeptide, resulting in inhibition of glycolysis and cell growth arrest in cell culture.

Section: Effect Of Extracellular Pyruvate On the Pgmtide-induced Inhimentioning

confidence: 99%

Phosphoglycerate Mutase-derived Polypeptide Inhibits Glycolytic Flux and Induces Cell Growth Arrest in Tumor Cell Lines

Engel

Mazurek

Eigenbrodt

et al. 2004

“…Bisphosphoglycerate mutase (BPGM) 2 and cofactor-dependent phosphoglycerate mutase (dPGM) are tri-functional enzymes, catalyzing a series of intermolecular phosphoryl group transfer reactions (3,4). Both BPGM and dPGM can catalyze the same three overall reactions for which phosphorylation of the catalytic histidine by 2,3-bisphosphoglycerate is the first step.…”

mentioning

confidence: 99%

Seeing the Process of Histidine Phosphorylation in Human Bisphosphoglycerate Mutase

Wang

Liu

Wei

et al. 2006

Bisphosphoglycerate mutase is an erythrocyte-specific enzyme catalyzing a series of intermolecular phosphoryl group transfer reactions. Its main function is to synthesize 2,3-bisphosphoglycerate, the allosteric effector of hemoglobin. In this paper, we directly observed real-time motion of the enzyme active site and the substrate during phosphoryl transfer. A series of high resolution crystal structures of human bisphosphoglycerate mutase co-crystallized with 2,3-bisphosphoglycerate, representing different time points in the phosphoryl transfer reaction, were solved. These structures not only clarify the argument concerning the substrate binding mode for this enzyme family but also depict the entire process of the key histidine phosphorylation as a "slow movie". It was observed that the enzyme conformation continuously changed during the different states of the reaction. These results provide direct evidence for an "in line" phosphoryl transfer mechanism, and the roles of some key residues in the phosphoryl transfer process are identified.

“…The phosphatase reaction can be stimulated by a number of anions including chloride, phosphate, and particularly by 2-phosphoglycolate (5). These three enzymic activities have been found to occur at a unique active site with two different binding sites for the substrates, one for bisphosphoglycerate and another for monophosphoglycerate (6,7).…”

mentioning

confidence: 99%

“…Based on its enzymatic properties and amino acid sequence homology, BPGM is closely related to the glycolytic housekeeping enzyme, cofactor (2,3-BPG)-dependent phosphoglycerate mutase (dPGM) (8,9), involved in glycolytic and gluconeogenic pathways with sequence identities in the 40 -50% range (6). In the SCOP data base, BPGM and dPGM are grouped into a superfamily along with fructose-2,6-bisphosphatases and acid phosphatase.…”

mentioning

confidence: 99%

Crystal Structure of Human Bisphosphoglycerate Mutase

Wang

Wei

Bian

et al. 2004

Bisphosphoglycerate mutase is a trifunctional enzyme of which the main function is to synthesize 2,3-bisphosphoglycerate, the allosteric effector of hemoglobin. The gene coding for bisphosphoglycerate mutase from the human cDNA library was cloned and expressed in Escherichia coli. The protein crystals were obtained and diffract to 2.5 Å and produced the first crystal structure of bisphosphoglycerate mutase. The model was refined to a crystallographic R-factor of 0.200 and R free of 0.266 with excellent stereochemistry. The enzyme remains a dimer in the crystal. The overall structure of the enzyme resembles that of the cofactor-dependent phosphoglycerate mutase except the regions of 13-21, 98 -117, 127-151, and the C-terminal tail. The conformational changes in the backbone and the side chains of some residues reveal the structural basis for the different activities between phosphoglycerate mutase and bisphosphoglycerate mutase. The bisphosphoglycerate mutase-specific residue Gly-14 may cause the most important conformational changes, which makes the side chain of Glu-13 orient toward the active site. The positions of Glu-13 and Phe-22 prevent 2,3-bisphosphoglycerate from binding in the way proposed previously. In addition, the side chain of Glu-13 would affect the Glu-89 protonation ability responsible for the low mutase activity. Other structural variations, which could be connected with functional differences, are also discussed.Bisphosphoglycerate mutase (BPGM) 1 is an erythrocyte-specific trifunctional enzyme. The main activity is that of synthase (BPGM, EC 5.4.2.4), catalyzing the formation of 2,3-bisphosphoglycerate (2,3-BPG) from 1,3-bisphosphoglycerate (1,3-BPG) (1-3) (see Fig. 1A). The second activity is that of a mutase (phosphoglycerate mutase, EC 5.4.2.1) catalyzing the interconversion between 2-and 3-phosphoglycerate (Fig. 1B) (4). The third activity, as a phosphatase (S-succinylglutathione hydrolase, EC 3.1.3.13), is to catalyze the hydrolysis of 2,3-BPG to 3-or 2-phosphoglycerate and a phosphate (Fig. 1C) (1, 2). The phosphatase reaction can be stimulated by a number of anions including chloride, phosphate, and particularly by 2-phosphoglycolate (5). These three enzymic activities have been found to occur at a unique active site with two different binding sites for the substrates, one for bisphosphoglycerate and another for monophosphoglycerate (6, 7).BPGM regulates the level of 2,3-BPG in human blood cells. In vivo, the concentration of 2,3-BPG is determined by the relative activities of the synthase and phosphatase reactions. In red blood cells, 2,3-BPG is the main allosteric effector of hemoglobin. It shifts the equilibrium between the oxy and deoxy conformations of hemoglobins by preferentially stabilizing the unliganded form. Sickle cell anemia is characterized by polymerization of deoxygenated hemoglobin mutants giving rise to deformed erythrocytes and vaso-occlusive complications. 2,3-BPG has been shown to facilitate this polymerization. The ability to modulate the 2,3-BPG level in vivo wou...