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Free access | 10.1172/JCI105883
Department of Medicine, University of California Los Angeles School of Medicine, Los Angeles, California 90024
Department of Pathology, University of California Los Angeles School of Medicine, Los Angeles, California 90024
Veterans Administration Center, Los Angeles, California 90073
Department of Pediatrics, University of Rochester School of Medicine and Strong Memorial Hospital, Rochester, New York 14620
Department of Internal Medicine, University of Rochester School of Medicine and Strong Memorial Hospital, Rochester, New York 14620
Department of Medicine, Dartmouth Medical School, Hanover, New Hampshire 03755
Find articles by Paglia, D. in: JCI | PubMed | Google Scholar
Department of Medicine, University of California Los Angeles School of Medicine, Los Angeles, California 90024
Department of Pathology, University of California Los Angeles School of Medicine, Los Angeles, California 90024
Veterans Administration Center, Los Angeles, California 90073
Department of Pediatrics, University of Rochester School of Medicine and Strong Memorial Hospital, Rochester, New York 14620
Department of Internal Medicine, University of Rochester School of Medicine and Strong Memorial Hospital, Rochester, New York 14620
Department of Medicine, Dartmouth Medical School, Hanover, New Hampshire 03755
Find articles by Valentine, W. in: JCI | PubMed | Google Scholar
Department of Medicine, University of California Los Angeles School of Medicine, Los Angeles, California 90024
Department of Pathology, University of California Los Angeles School of Medicine, Los Angeles, California 90024
Veterans Administration Center, Los Angeles, California 90073
Department of Pediatrics, University of Rochester School of Medicine and Strong Memorial Hospital, Rochester, New York 14620
Department of Internal Medicine, University of Rochester School of Medicine and Strong Memorial Hospital, Rochester, New York 14620
Department of Medicine, Dartmouth Medical School, Hanover, New Hampshire 03755
Find articles by Baughan, M. in: JCI | PubMed | Google Scholar
Department of Medicine, University of California Los Angeles School of Medicine, Los Angeles, California 90024
Department of Pathology, University of California Los Angeles School of Medicine, Los Angeles, California 90024
Veterans Administration Center, Los Angeles, California 90073
Department of Pediatrics, University of Rochester School of Medicine and Strong Memorial Hospital, Rochester, New York 14620
Department of Internal Medicine, University of Rochester School of Medicine and Strong Memorial Hospital, Rochester, New York 14620
Department of Medicine, Dartmouth Medical School, Hanover, New Hampshire 03755
Find articles by Miller, D. in: JCI | PubMed | Google Scholar
Department of Medicine, University of California Los Angeles School of Medicine, Los Angeles, California 90024
Department of Pathology, University of California Los Angeles School of Medicine, Los Angeles, California 90024
Veterans Administration Center, Los Angeles, California 90073
Department of Pediatrics, University of Rochester School of Medicine and Strong Memorial Hospital, Rochester, New York 14620
Department of Internal Medicine, University of Rochester School of Medicine and Strong Memorial Hospital, Rochester, New York 14620
Department of Medicine, Dartmouth Medical School, Hanover, New Hampshire 03755
Find articles by Reed, C. in: JCI | PubMed | Google Scholar
Department of Medicine, University of California Los Angeles School of Medicine, Los Angeles, California 90024
Department of Pathology, University of California Los Angeles School of Medicine, Los Angeles, California 90024
Veterans Administration Center, Los Angeles, California 90073
Department of Pediatrics, University of Rochester School of Medicine and Strong Memorial Hospital, Rochester, New York 14620
Department of Internal Medicine, University of Rochester School of Medicine and Strong Memorial Hospital, Rochester, New York 14620
Department of Medicine, Dartmouth Medical School, Hanover, New Hampshire 03755
Find articles by McIntyre, O. in: JCI | PubMed | Google Scholar
Published August 1, 1968 - More info
Atypical cases of heritable hemolytic anemia have been noted that conform clinically and biochemically to anemias of the pyruvatekinase (PK)-deficient type, except for the presence of apparently adequate quantities of erythrocyte-PK activity by the usual assay procedure. Investigations of four such anomalous cases, occurring in two unrelated families, are presented. Erythrocytes contained a kinetically aberrant isozyme of pyruvate kinase (PK2). Michaelis constants for the pathologic isozyme relative to phosphoenolpyruvate were over 10-fold greater than control values, but no kinetic abnormality was evident for the second substrate, adenosine diphosphate. PK2 exhibited a pH optimum almost 1 U lower than the wild enzyme form (PK1). Significant differences were also evident in the functional stabilities of the isozymes. Leukocytes were unaffected.
Family studies revealed paternal heterozygosity for quantitative PK deficiency of the usual type. Clinically normal maternal relatives and some siblings demonstrated intermediate deviations in erythrocyte-PK kinetics and reaction characteristics compatible with coexistence of normal PK1 and kinetically abnormal PK2. Hemolytic anemia in the propositi appeared to require simultaneous inheritance of the gene governing PK2 production and its presumed allele resulting in quantitative PK deficiency. Both genetic defects were traced through three generations, the defective gene in both instances apparently resident on autosomes.
A revision of the PK assay technique is suggested, since catalytic inefficiency of PK2 was manifested only at low substrate concentrations and was therefore undetectable at the relatively high phosphoenolpyruvate levels employed in the conventional assay.
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