Equine Infectious Anemia Pyruvate Kinase Deficiency in the Red Cells of Thoroughbred Horses

2010 ◽  
Vol 23 (6) ◽  
pp. 479-484
Author(s):  
L. O. Medeiros ◽  
L. F. Medeiros ◽  
S. R. Barcelos ◽  
S. Ferri ◽  
U. R. Reiner
Keyword(s):  
Pyruvate Kinase ◽  
Red Cells ◽  
Pyruvate Kinase Deficiency ◽  
Thoroughbred Horses ◽  
Equine Infectious Anemia

scholarly journals Glycolate kinase activity in human red cells

Blood ◽  
1985 ◽  
Vol 65 (2) ◽  
pp. 480-483 ◽  
Author(s):  
S Fujii ◽  
E Beutler
Keyword(s):  
Pyruvate Kinase ◽  
Adenosine Triphosphate ◽  
Kinase Activity ◽  
Maximum Velocity ◽  
Red Cells ◽  
Half Maximum ◽  
Ph Optimum ◽  
Pyruvate Kinase Deficiency ◽  
Low Activity ◽  
Human Red Cells

Abstract Human red cells manifest glycolate kinase activity. This activity copurifies with pyruvate kinase and is decreased in the red cells of subjects with hereditary pyruvate kinase deficiency. Glycolate kinase activity was detected in the presence of FDP or glucose-1,6-P2. In the presence of 1 mmol/L FDP, the Km for adenosine triphosphate (ATP) was 0.28 mmol/L and a half maximum velocity for glycolate was obtained at 40 mmol/L. The pH optimum of the reaction was over 10.5 With 10 mumol/L FDP, 500 mumol/L glucose-1,6-P2, 2 mmol/L ATP, 5 mmol/L MgCl2, and 50 mmol/L glycolate at pH 7.5, glycolate kinase activity was calculated to be approximately 0.0013 U/mL RBC. In view of this low activity even in the presence of massive amounts of glycolate, the glycolate kinase reaction cannot account for the maintenance of the reported phosphoglycolate level in human red cells.

scholarly journals Glycolate kinase activity in human red cells

Blood ◽  
1985 ◽  
Vol 65 (2) ◽  
pp. 480-483
Author(s):  
S Fujii ◽  
E Beutler
Keyword(s):  
Pyruvate Kinase ◽  
Adenosine Triphosphate ◽  
Kinase Activity ◽  
Maximum Velocity ◽  
Red Cells ◽  
Half Maximum ◽  
Ph Optimum ◽  
Pyruvate Kinase Deficiency ◽  
Low Activity ◽  
Human Red Cells

Human red cells manifest glycolate kinase activity. This activity copurifies with pyruvate kinase and is decreased in the red cells of subjects with hereditary pyruvate kinase deficiency. Glycolate kinase activity was detected in the presence of FDP or glucose-1,6-P2. In the presence of 1 mmol/L FDP, the Km for adenosine triphosphate (ATP) was 0.28 mmol/L and a half maximum velocity for glycolate was obtained at 40 mmol/L. The pH optimum of the reaction was over 10.5 With 10 mumol/L FDP, 500 mumol/L glucose-1,6-P2, 2 mmol/L ATP, 5 mmol/L MgCl2, and 50 mmol/L glycolate at pH 7.5, glycolate kinase activity was calculated to be approximately 0.0013 U/mL RBC. In view of this low activity even in the presence of massive amounts of glycolate, the glycolate kinase reaction cannot account for the maintenance of the reported phosphoglycolate level in human red cells.

Life-Span and Organ Sequestration of the Red Cells in Pyruvate Kinase Deficiency

1968 ◽  
Vol 278 (2) ◽  
pp. 73-81 ◽  
Author(s):  
David G. Nathan ◽  
Frank A. Oski ◽  
Denis R. Miller ◽  
Frank H. Gardner
Keyword(s):  
Life Span ◽  
Pyruvate Kinase ◽  
Red Cells ◽  
Pyruvate Kinase Deficiency

Small Molecule Activation Of Pyruvate Kinase Normalizes Metabolic Activity In Red Cells From Patients With Pyruvate Kinase Deficiency-Associated Hemolytic Anemia

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 2180-2180
Author(s):  
Charles Kung ◽  
Jeff Hixon ◽  
Penelope Kosinski ◽  
Gavin Histen ◽  
Collin Hill ◽  
...  
Keyword(s):  
Enzyme Activity ◽  
Pyruvate Kinase ◽  
Half Life ◽  
Red Cells ◽  
Red Cell ◽  
Wild Type ◽  
Employment Equity ◽  
Pyruvate Kinase Deficiency ◽  
Chronic Hemolysis ◽  
Equity Ownership

Abstract Pyruvate kinase deficiency (PKD) is an autosomal recessive enzymopathy that is the most common cause of hereditary nonspherocytic hemolytic anemia (HNSHA). PKD is a rare disease characterized by a life-long chronic hemolysis with severe co-morbidities. It is hypothesized that insufficient energy production to maintain red cell membrane homeostasis promotes the chronic hemolysis. Treatment is generally palliative, focusing on the resultant anemia, and there are no approved drugs that directly target mutated pyruvate kinase. Here, we describe the mechanism of action and cellular effects of AG-348, an allosteric activator of the red cell isoform of pyruvate kinase (PKR). Hundreds of mutant alleles of PKR have been identified and are known to have deleterious effects on catalytic activity, protein stability, or protein expression. We demonstrate that AG-348 can potently activate a spectrum of recombinantly expressed PKR mutant proteins, including mutations that span distinct subdomains of the enzyme. The R532W mutation is quite sensitive to AG-348 modulation, with over 4-fold activation of the enzyme activity, even as the mutation renders PKR insensitive to stimulation by its endogenous allosteric regulator fructose 1,6-bisphosphate (FBP) (Figure A). Crystallographic analysis reveals that very few mutations associated with PKD occur within the AG-348 binding pocket, accounting for its broad activity. The binding of AG-348 attenuates the thermostability defect of several mutant alleles of PKR, including the commonly observed R510Q mutant that has a half-life of ∼2% of the half-life of wild-type PKR when incubated at 53°C. Pre-incubation of the R510Q protein with AG-348 restores the half-life to ∼70% that of the wild-type enzyme (Figure B). PKD red cells are characterized by changes in metabolism associated with defective glycolysis, including a build-up of the PKR substrate phosphenolpyruvate (PEP) and deficiency in the PKR product adenosine triphosphate (ATP). PKD red cells from several patients with distinct compound heterozygous PKR mutations exposed to AG-348 had increased PKR enzyme activity (up to 4-fold over control) and showed consistent dose and time-dependent metabolic responses (Figure C), including sharp reductions in PEP (up to 70% compared to control) and increases in ATP levels (up to 100% over control). These responses were observed in patient samples harboring PKR mutations that we had studied biochemically (including R486W and R510Q), but also in an instance where the mutation had not previously been biochemically characterized (A495V). In these ex-vivo settings, ATP levels in AG-348 treated cells can reach levels that are typical of normal, non-PKD red cells. These data support the hypothesis that drug intervention with AG-348 may restore glycolytic pathway activity and normalize red cell metabolism in vivo. This therapeutic approach may be an effective way to correct the underlying pathology of PKD and, importantly, provide clinical benefit to patients. Disclosures: Kung: Agios Pharmaceuticals: Employment, Equity Ownership. Hixon:Agios Pharmaceuticals: Employment, Equity Ownership. Kosinski:Agios Pharmaceuticals: Employment, Equity Ownership. Histen:Agios Pharmaceuticals: Employment, Equity Ownership. Hill:Agios Pharmaceuticals: Employment, Equity Ownership. Si:Agios Pharmaceuticals: Employment, Equity Ownership. Kernytsky:Agios Pharmaceuticals: Employment, Equity Ownership. Chen:Agios Pharmaceuticals: Employment, Equity Ownership. DeLaBarre:Agios Pharmaceuticals: Employment, Equity Ownership. Clasquin:Agios Pharmaceuticals: Employment, Equity Ownership. Ho:Agios Pharmaceuticals: Employment, Equity Ownership. Salituro:Agios Pharmaceuticals: Employment, Equity Ownership. Popovici-Muller:Agios Pharmaceuticals: Employment, Equity Ownership. Agresta:Agios Pharmaceuticals: Employment, Equity Ownership. Silverman:Agios Pharmaceuticals: Employment, Equity Ownership. Dang:Agios Pharmaceuticals: Employment, Equity Ownership.

scholarly journals A Sri Lankan girl with a new genetic variant in the PKLR gene causing pyruvate kinase deficiency: a case report

2021 ◽  
Vol 15 (1) ◽  
Author(s):  
Ahalyaa Sivashangar ◽  
Lallindra Gooneratne ◽  
Barnaby Clark ◽  
David Rees ◽  
Saroj Jayasinghe ◽  
...  
Keyword(s):  
Case Report ◽  
Pyruvate Kinase ◽  
Genetic Variant ◽  
Asian Population ◽  
Pathogenic Variant ◽  
Sri Lankan ◽  
Recessive Trait ◽  
Case Presentation ◽  
Pyruvate Kinase Deficiency ◽  
Hematological Disorders

Abstract Background Erythrocyte pyruvate kinase is expressed under the control of the PKLR gene located on chromosome 1q21. Pyruvate kinase catalyzes the final steps of the glycolytic pathway and creates 50% of the red cell total adenosine triphosphate. Pyruvate kinase deficiency is the commonest glycolytic defect causing congenital non-spherocytic hemolytic anemia inherited in an autosomal recessive trait in which homozygotes and compound heterozygotes are common. Over 200 mutations have been described in patients with pyruvate kinase deficiency. This case report identifies a new pathogenic variant in PKLR gene detected in a patient with severe pyruvate kinase deficiency. Case presentation A Sri Lankan Sinhalese girl who developed neonatal anemia and jaundice within 24 hours of birth with mild hepatomegaly. She was from a nonconsanguineous marriage and had two siblings who had no hematological disorders. She had repeated admissions due to similar illnesses and at the age of 8 years was found to have pyruvate kinase deficiency associated with a novel homozygous pathogenic variant c.507+1delG in the PKLR gene. Conclusions A novel genetic variant in PKLR gene, consistent with pyruvate kinase deficiency, was detected in a Sri Lankan girl. This genetic variant may be specific to the Asian population and requires further studies.

Six novel variants in the PKLR gene associated with pyruvate kinase deficiency in Argentinian patients

2021 ◽  
Author(s):  
Berenice Milanesio ◽  
Carolina Pepe ◽  
Lucas A. Defelipe ◽  
Silvia Eandi Eberle ◽  
Vanesa Avalos Gomez ◽  
...  
Keyword(s):  
Pyruvate Kinase ◽  
Pyruvate Kinase Deficiency ◽  
Novel Variants

IRON OVERLOAD IN CONGENITAL ERYTHROCYTE PYRUVATE KINASE DEFICIENCY

1980 ◽  
Vol 1 (11) ◽  
pp. 531-532 ◽  
Author(s):  
H. H. Salem ◽  
M. B. Van Der Weyden ◽  
B. G. Firkin
Keyword(s):  
Iron Overload ◽  
Pyruvate Kinase ◽  
Pyruvate Kinase Deficiency
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