A liver-type mutation in a case of pronounced erythrocyte phosphofructokinase deficiency without clinical expression.
A marked erythrocyte phosphofructokinase deficiency was detected in a healthy man. His enzymatic activity was only 25% that of normal controls. His father and his son had erythrocytic phosphofructokinase activities of 50-55% that of normal controls. The chromatographic separation of erythrocytic phosphofructokinase isozymes, as well as immunological studies revealed a decrease in L-type phosphofructokinase activity. The lowered erythrocytic L-type phosphofructokinase activity was not accompanied by a decreased level of L-type phosphofructokinase in proteins. The L/M subunit ratio was similar to that of normal subjects. The defect resulted from the synthesis of stable L-type mutant subunit with high electrophoretic mobility. White blood cells, which synthesize mostly the same isozyme as L-type phosphofructokinase also showed a decreased activity and a high electrophoretic mobility. In spite of this important deficiency, and of significant metabolic alterations (a slight decrease in ATP; 2,3-diphosphoglycerate; triose phosphate), hemolysis did not appear in the propositus.
D000936:Antigen-Antibody Complex; D004912:Erythrocytes / Q000201:enzymology*; D006801:Humans; D007106:Immune Sera; D007700:Kinetics; D008099:Liver / Q000201:enzymology*; D008297:Male; D008875:Middle Aged; D009154:Mutation; D010732:Phosphofructokinase-1 / Q000097:blood / Q000172:deficiency* / Q000235:genetics; D012016:Reference Values
D000936:Antigen-Antibody Complex; D007106:Immune Sera; D010732:Phosphofructokinase-1