title: Muscle phosphofructokinase deficiency. Biochemical and immunological studies of phosphofructokinase isozymes in muscle culture.
abstract: Muscle cultures from three unrelated patients with muscle phosphofructokinase (PFK; EC 2.7.1.11) deficiency (Glycogenosis type VII; Tarui disease) had normal PFK activity and normal morphology. Chromatographic and immunological studies showed that normal muscle cultures express all three PFK subunits, M (muscle-type), L (liver-type), and P (platelet-type) and contain multiple homotetrameric and heterotetrameric isozymes. Muscle cultures from patients lack catalytically active M subunit-containing isozymes, but this is compensated for by the presence of P- and L-containing isozymes. Despite the lack of muscle-type PFK activity, presence of immunoreactive M subunit was demonstrable by indirect immunofluorescence, suggesting a mutation of the structural gene coding for the M-subunit of PFK.
mesh_terms: D000328:Adult; D000818:Animals; D000937:Antigen-Antibody Reactions; D002239:Carbohydrate Metabolism, Inborn Errors / Q000097:blood / Q000201:enzymology; D046508:Culture Techniques; D005455:Fluorescent Antibody Technique; D006801:Humans; D007527:Isoenzymes / Q000172:deficiency* / Q000276:immunology / Q000378:metabolism; D008297:Male; D051379:Mice; D008875:Middle Aged; D009132:Muscles / Q000201:enzymology* / Q000276:immunology; D010732:Phosphofructokinase-1 / Q000172:deficiency* / Q000276:immunology / Q000378:metabolism
chemical_list: D007527:Isoenzymes; D010732:Phosphofructokinase-1