Human erythrocyte 2,3-diphosphoglycerate metabolism. Influence of 1,3-diphosphoglycerate and Pi

Momsen, Günther; Vestergaard-Bogind, B.

doi:10.1016/0003-9861(78)90254-0

Cited by 23 publications

(14 citation statements)

References 42 publications

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“…In addition, the in itro kinetic parameters for the phosphatase appear to give estimates of activity considerably less than those observed in intact erythrocytes [11]. This could be due to the presence of the potent phosphatase activator, 2-phosphoglycollate (2-PGly), in i o [9,12] or it could be due to the inhibition of the phosphatase by 3-phosphoglycerate (3-PGA) being much weaker than that observed in itro [13,14].…”

Section: P Nmr Introductionmentioning

confidence: 96%

“…Synthase activity can be inhibited by stopping 1,3-bisphosphoglycerate (1,3-BPG) production ; this is achieved by incubating the cells in the absence of glucose (Glc) or by inhibiting glycolysis at the glyceraldehyde-3-phosphate dehydrogenase step, or at proximal reactions in the pathway [10,15,16]. Alternatively the synthase activity can be inhibited by decreasing the pH ; this inhibition may be due to a decreased supply of 1,3-BPG [13] or pH-dependent inhibition of the synthase [10]. The K m of the phosphatase for 2,3-BPG is significantly lower than the normal in i o concentration of 2,3-BPG [11] and hence determination of the phosphatase activity should be independent of 2,3-BPG concentration.…”

Section: P Nmr Introductionmentioning

confidence: 99%

“…The K m of the phosphatase for 2,3-BPG is significantly lower than the normal in i o concentration of 2,3-BPG [11] and hence determination of the phosphatase activity should be independent of 2,3-BPG concentration. A problem with this method is, however, that 2,3-BPG depletion causes the accumulation of P i ; and P i has been shown to activate the phosphatase both in itro [11] and in i o [13]. Thus it has been claimed that the phosphatase activities determined by this method (20-25 % of the glycolytic flux [10,15,16]) are in excess of the normal in i o activity [13].…”

Section: P Nmr Introductionmentioning

confidence: 99%

“…Model of 2,3-bisphosphoglycerate metabolism in the human erythrocyte based on detailed enzyme kinetic equations 1 : in vivo kinetic characterization of 2,3-bisphosphoglycerate synthase/phosphatase using 13 C and 31…”

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Model of 2,3-bisphosphoglycerate metabolism in the human erythrocyte based on detailed enzyme kinetic equations1: in vivo kinetic characterization of 2,3-bisphosphoglycerate synthase/phosphatase using 13C and 31P NMR

Mulquiney¹,

BUBB²,

Kuchel³

1999

Biochem. J.

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This is the first in a series of three papers [see also Mulquiney and Kuchel (1999) Biochem. J. 342, 579-594; Mulquiney and Kuchel (1999) Biochem. J. 342, 595-602] that present a detailed mathematical model of erythrocyte metabolism which explains the regulation and control of 2,3-bisphosphoglycerate (2,3-BPG) metabolism. 2,3-BPG is a modulator of haemoglobin oxygen affinity and hence plays an important role in blood oxygen transport and delivery. This paper presents an in vivo kinetic characterization of 2,3-BPG synthase/phosphatase (BPGS/P), the enzyme that catalyses both the synthesis and degradation of 2,3-BPG. Much previous work had indicated that the behaviour of this enzyme in vitro is markedly different from that in vivo. (13)C and (31)P NMR were used to monitor the time courses of selected metabolites when erythrocytes were incubated with or without [U-(13)C]glucose. Simulations of the experimental time courses were then made. By iteratively changing the parameters of the BPGS/P part of the model until a good match between the NMR-derived data and simulations were achieved, it was possible to characterize BPGS/P kinetically in vivo. This work revealed that: (1) the pH-dependence of the synthase activity results largely from a strong co-operative inhibition of the synthase activity by protons; (2) 3-phosphoglycerate and 2-phosphoglycerate are much weaker inhibitors of 2,3-BPG phosphatase in vivo than in vitro; (3) the K(m) of BPGS/P for 2,3-BPG is significantly higher than that measured in vitro; (4) the maximal activity of the phosphatase in vivo is approximately twice that in vitro, when P(i) is the sole activator (second substrate); and (5) 2-phosphoglycollate appears to play no role in the activation of the phosphatase in vivo. Using the newly determined kinetic parameters, the percentage of glycolytic carbon flux that passes through the 2, 3-BPG shunt in the normal in vivo steady state was estimated to be 19%.

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Section: P Nmr Introductionmentioning

confidence: 96%

Section: P Nmr Introductionmentioning

confidence: 99%

Section: P Nmr Introductionmentioning

confidence: 99%

mentioning

confidence: 99%

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Model of 2,3-bisphosphoglycerate metabolism in the human erythrocyte based on detailed enzyme kinetic equations1: in vivo kinetic characterization of 2,3-bisphosphoglycerate synthase/phosphatase using 13C and 31P NMR

Mulquiney¹,

BUBB²,

Kuchel³

1999

Biochem. J.

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“…We thereby indirectly estimated that the capacity of MIPP1 to hydrolyze 2,3-BPG in vivo is 0.6 Ϯ 0.05 mmol/liter of cells per h (n ϭ 4). In comparison, BPGM hydrolyzes 0.1-0.5 mmol 2,3-BPG/liter of cells per h (2,28). Thus, our data reveal that MIPP1 is a major 2,3-BPG phosphatase on par with BPGM.…”

mentioning

confidence: 57%

Dephosphorylation of 2,3-bisphosphoglycerate by MIPP expands the regulatory capacity of the Rapoport–Luebering glycolytic shunt

Cho

King

Qian

et al. 2008

Proc. Natl. Acad. Sci. U.S.A.

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The Rapoport-Luebering glycolytic bypass comprises evolutionarily conserved reactions that generate and dephosphorylate 2,3-bisphosphoglycerate (2,3-BPG). For >30 years, these reactions have been considered the responsibility of a single enzyme, the 2,3-BPG synthase/2-phosphatase (BPGM). Here, we show that Dictyostelium, birds, and mammals contain an additional 2,3-BPG phosphatase that, unlike BPGM, removes the 3-phosphate. This discovery reveals that the glycolytic pathway can bypass the formation of 3-phosphoglycerate, which is a precursor for serine biosynthesis and an activator of AMP-activated protein kinase. Our 2,3-BPG phosphatase activity is encoded by the previously identified gene for multiple inositol polyphosphate phosphatase (MIPP1), which we now show to have dual substrate specificity. By genetically manipulating Mipp1 expression in Dictyostelium, we demonstrated that this enzyme provides physiologically relevant regulation of cellular 2,3-BPG content. Mammalian erythrocytes possess the highest content of 2,3-BPG, which controls oxygen binding to hemoglobin. We determined that total MIPP1 activity in erythrocytes at 37°C is 0.6 mmol 2,3-BPG hydrolyzed per liter of cells per h, matching previously published estimates of the phosphatase activity of BPGM. MIPP1 is active at 4°C, revealing a clinically significant contribution to 2,3-BPG loss during the storage of erythrocytes for transfusion. Hydrolysis of 2,3-BPG by human MIPP1 is sensitive to physiologic alkalosis; activity decreases 50% when pH rises from 7.0 to 7.4. This phenomenon provides a homeostatic mechanism for elevating 2,3-BPG levels, thereby enhancing oxygen release to tissues. Our data indicate greater biological significance of the Rapoport-Luebering shunt than previously considered.2,3-BPG ͉ erythrocyte ͉ glycolysis T he Rapoport-Luebering glycolytic shunt generates and dephosphorylates 2,3-bisphosphoglycerate (2,3-BPG). These reactions have been considered to be catalyzed by a single 2,3-BPG synthase/2-phosphatase (BPGM) (1, 2). This enzyme has mutase activity that converts the glycolytic intermediate, 1,3-BPG, to 2,3-BPG. BPGM also acts as a phosphatase, converting 2,3-BPG to 3-phosphoglycerate (3-PG), which then reenters the main glycolytic pathway. This has been the textbook perception of this metabolic pathway for Ͼ25 years (3).Metabolic flux through the Rapoport-Luebering shunt carries an energetic cost for the cell because it bypasses the ATPgenerating phosphoglycerate kinase. Nevertheless, in vertebrates and lower eukaryotes, 2,3-BPG fulfills an essential role in glycolysis by priming the phosphoglycerate mutase reaction that converts 3-PG to 2-PG (4). More recently, experiments in Dictyostelium have suggested that 2,3-BPG, through an unknown mechanism, provides a molecular link between the turnover of phosphorylated inositol derivatives and glycolytic flux (5). Nonetheless, the most well studied function for 2,3-BPG is its regulation of whole-body oxygen homeostasis; 2,3-BPG executes this role because it is the main allosteri...

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The Enzymology of 2, 3‐Bisphosphoglycerate

Rose

1980

Advances in Enzymology - And Related Areas of Molecular Biology

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Human erythrocyte 2,3-diphosphoglycerate metabolism. Influence of 1,3-diphosphoglycerate and Pi

Cited by 23 publications

References 42 publications

Model of 2,3-bisphosphoglycerate metabolism in the human erythrocyte based on detailed enzyme kinetic equations1: in vivo kinetic characterization of 2,3-bisphosphoglycerate synthase/phosphatase using 13C and 31P NMR

Model of 2,3-bisphosphoglycerate metabolism in the human erythrocyte based on detailed enzyme kinetic equations1: in vivo kinetic characterization of 2,3-bisphosphoglycerate synthase/phosphatase using 13C and 31P NMR

Dephosphorylation of 2,3-bisphosphoglycerate by MIPP expands the regulatory capacity of the Rapoport–Luebering glycolytic shunt

The Enzymology of 2, 3‐Bisphosphoglycerate

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