The first case of a complete deficiency of diphosphoglycerate mutase in human erythrocytes.

A 28-year-old asymptomatic male of Iranian Jewish (Meshadi) heritage was found on routine exam to have an erythrocytosis (RBC = 6.22 · 10 12 /l, Hgb = 19.2 g/dl, Hct = 58.9%). Splenomegaly was absent on physical exam. There was no family history of erythrocytosis. His oxygen dissociation curve was left-shifted with a p 50 of 19 mmHg (normal = 25-32 mmHg). Hemoglobin electrophoresis showed no abnormalities. DNA sequencing of the hemoglobin b globin gene and both a globin genes did not reveal a mutation. A 2,3-bisphosphoglycerate (BPG) level was markedly decreased at 0.3 mmol/g Hb (normal = 11.4-19.4 mmol/g Hb). The patient's bisphosphoglycerate mutase (BPGM) enzyme activity was also markedly decreased at 0.16 IU/g Hb (normal = 4.13-5.43 IU/g Hb). A red cell enzyme panel revealed a markedly decreased G-6-PD level (0.3 U/g Hb, normal = 8.6-18.6 U/g Hb). His parents and a brother were also available for evaluation. Both parents showed normal 2,3-BPG levels but BPGM activity approximately 50% of normal. Paradoxically, the brother showed normal BPGM activity but a slightly decreased 2,3-BPG level. All family members had markedly decreased G-6-PD activity. DNA sequencing of the BPGM gene showed the propositus to be homozygous for 185 GfiA, Arg 62 Gln in exon 2. Thus, the erythrocytosis in this patient is secondary to low 2,3-BPG levels, due to a deficiency in BPG mutase. This appears due to consanguinity within this family. Am.

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“…There was no laboratory evidence of hemolysis. Isoelectric focusing did not show a hemoglobin variant [13].…”

Section: Discussionmentioning

confidence: 72%

Erythrocytosis due to bisphosphoglycerate mutase deficiency with concurrent glucose‐6‐phosphate dehydrogenase (G‐6‐PD) deficiency

et al. 2004

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“…A prokaryotic expression vector constructed in our laboratory (23) was used to synthesize wild-type and mutant forms of BPGM in Escherichia coli. Analysis of the catalytic properties of variants have shown that Arg 89 is specifically involved in the monophosphoglycerate-binding sites (24) as has been reported for a natural human BPGM variant (25)(26)(27). In contrast, we have shown that Gly 13 is specifically involved in the diphosphoglycerate-binding sites and that replacement of Gly 13 by a positively charged amino acid residue greatly activates the phosphatase reaction, whereas the synthase and mutase reactions are greatly reduced (28).…”

mentioning

confidence: 71%

“…Mutase activity was measured as described previously (25). The catalytic constants of synthase and mutase activity were calculated using the ⑀ of NADH of 6 mM Ϫ1 cm Ϫ1 at 334 nm and by fitting experimental points to the Michaelis-Menten equation with a nonlinear iterative regression program.…”

Section: Methodsmentioning

confidence: 99%

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Critical Role of Human Bisphosphoglycerate Mutase Cys22 in the Phosphatase Activator-binding Site

Ravel

Craescu

Arous

et al. 1997

Journal of Biological Chemistry

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The enzymatic activities catalyzed by bisphosphoglycerate mutase (BPGM, EC 5.4.2.4) have been shown to occur at a unique active site, with distinct binding sites for diphosphoglycerates and monophosphoglycerates. The physiological phosphatase activator (2-phosphoglycolate) binds to BPGM at an undetermined site. BPGM variants were constructed by site-directed mutagenesis of three amino acid residues in the active site to identify residues specifically involved in the binding of the monophosphoglycerates and 2-phosphoglycolate. Substitution of Cys 22 by functionally conservative residues, Thr or Ser, caused a great decrease in 2-phosphoglycolate-stimulated phosphatase activity and in the K a value of the activator, whereas it caused no change in other catalytic activities or in the K m values of 2,3-diphosphoglycerate (2,3-DPG) and glycerate 3-phosphate (3-PG, EC 1.1.1.12), indicating that Cys 22 is specifically involved either directly or indirectly in 2-phosphoglycolate binding.Kinetic experiments showed that the K a of the cofactor and the K m of 3-PG were affected by the substitution of Ser 23 indicating that this residue is necessary for the fixation of both 3-PG and 2-phosphoglycolate. The R89K variant has previously been shown to have a modified K m value for monophosphoglycerates, however, its affinity for 2-phosphoglycolate is unaltered, suggesting that Arg 89 is specifically involved in monophosphoglycerates binding.CD spectroscopic studies of substrates and cofactor binding showed that 2,3-DPG induced structural modifications of normal and mutated enzymes which could be due to protein phosphorylation. Addition of 2-phosphoglycolate to phosphorylated proteins with normal affinity for the cofactor produced spectra with the same characteristics as unphosphorylated species.In summary, monophosphoglycerates and 2-phosphoglycolate have partially distinct binding sites in human BPGM. The specific implication of the Cys 22 residue in 2-phosphoglycolate binding is of great significance in the design of analogs of therapeutic benefit.

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“…Calculated range of disease Properties of deficient enzymes Number of References diseased minimum range of minimum enzyme unstable kinetic change in persons survival chronic normal activity variants change isoenzyme activity disease activity Tanaka, 1990;Valentine, 1983;Board, 1978;Rijksen, 1983;Miwa, 1985;Paglia, 1981;Necheles, 1970Tanka, 1990Paglia, 1974;Zanella, 1980;Neubauer, 1990;Arnold, 1973Tanka, 1990Vora, 1983;Valentine, 1984 ;Fogelfeld, 1990Kishi, 1987Miwa, 1981 ;Valentine, 1984Eber, 1979Valentine, 1984;Rosa, 1985 ;Zanella, 1985Waller, 1974Tanaka, 1990Maeda, 1991 ;Fujii, 1980Fujii, , 1992Valentine, 1984Schroter, 1965Rosa, 1973Rosa, , 1978Buc, 1974;Rosa, 1989;Tanaka, 1990 Syllm- Rapoport, 1965…”

Section: Enzymementioning

confidence: 99%

Use of Mathematical Models for Predicting the Metabolic Effect of Large-Scale Enzyme Activity Alterations. Application to Enzyme Deficiencies of Red Blood Cells

Schuster

Holzhütter

1995

Eur J Biochem

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There are numerous examples showing that the metabolism of cells can be severely impaired if the activity of only one of the participating enzymes undergoes large-scale alterations, resulting, for example, from spontaneous mutations (inherited or aquired enzymopathies), the administration of toxic drugs or self-inactivation of enzymes during cell aging. However, a quantitative relationship between the degree of enzyme deficiency and the extent of metabolic dysfunction is very difficult to establish by experimental means. An alternative is to tackle this problem by mathematical modelling. Our approach is based on a comprehensive mathematical model of the energy and redox metabolism for human erythrocytes. We calculate stationary states of the cell metabolism, varying the activity of each of the participating enzymes by several orders of magnitude. The metabolic states are then evaluated in terms of a performance function which relates the metabolic variables to the overall functional fitness of the cell. The performance function for the erythrocyte takes into account the homeostasis of three essential metabolic variables : the energetic state (ATP), the reductive capacity (reduced glutathione), and the osmotic state. Based on the behaviour of the performance function at varying enzyme activities, we estimate those ranges of enzyme activities, in which the metabolic alterations should be either tolerable, associated with non-chronic or chronic diseases, or letal. For most enzymopathies, the experimental and clinical observations can be satisfactorily rationalized by the computational results. Moreover, a surprisingly high correlation is found between the range of the activity range where disease is predicted by the model and the observed number of diseased probands.Another objective of our study was to contribute to the theory of metabolic control. The well-elaborated concept of the metabolic control theory is restricted to (infinitely) small activity alterations. In order to quantify the metabolic effect of finite (large-scale) changes in the activity of an enzyme, we propose, as a control measure, the effective activity Em, defined as the relative activity of an enzyme (with respect to the activity in a reference state) required to bring about a change in the stationary value of a metabolic variable by the (finite) factor a. We demonstrate that none of the existing extrapolation methods using the conventional control coefficient is capable to provide reliable predictions of the effective activities for all enzymes of erythrocyte metabolism.

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The first case of a complete deficiency of diphosphoglycerate mutase in human erythrocytes.

Cited by 116 publications

References 35 publications

Erythrocytosis due to bisphosphoglycerate mutase deficiency with concurrent glucose‐6‐phosphate dehydrogenase (G‐6‐PD) deficiency

Erythrocytosis due to bisphosphoglycerate mutase deficiency with concurrent glucose‐6‐phosphate dehydrogenase (G‐6‐PD) deficiency

Critical Role of Human Bisphosphoglycerate Mutase Cys22 in the Phosphatase Activator-binding Site

Use of Mathematical Models for Predicting the Metabolic Effect of Large-Scale Enzyme Activity Alterations. Application to Enzyme Deficiencies of Red Blood Cells

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