Magnani M, Stocchi V, Canestrari F, Dachà M, Balestri P, Farnetani M A, Giorgi D, Fois A, Fornaini G
Br J Haematol. 1985 Sep;61(1):41-50. doi: 10.1111/j.1365-2141.1985.tb04058.x.
A 14-month-old child who had a haemolytic episode when he was 5 years old, and with psychomotor retardation, was found to have decreased red cell hexokinase activity. The mutant enzyme was characterized by an increased affinity for glucose associated with an increased inhibition constant for glucose-1,6-diphosphate. Affinity for Mg ATP2-, heat stability and pH-optimum were normal. The isozymic pattern of the red cell enzyme was normal but all the molecular forms were present in reduced amounts. The kinetics of decay of hexokinase during cell ageing was also normal. Glucose consumption of the hexokinase deficient cells was 60-65% of the controls while the amount metabolized through the hexose monophosphate shunt was unchanged. Red cell 2,3-diphosphoglycerate and glucose-6-phosphate levels were normal in the proband but reduced in the erythrocytes of his parents, who were heterozygous for the defect but had normal haematological data. Comparison with the 13 previously reported cases of hexokinase deficiency confirms the broad phenotypic variability that characterizes this disorder.
一名14个月大的儿童在5岁时曾发生溶血发作，并有精神运动发育迟缓，发现其红细胞己糖激酶活性降低。该突变酶的特点是对葡萄糖的亲和力增加，同时对葡萄糖-1,6-二磷酸的抑制常数增加。对Mg ATP2-的亲和力、热稳定性和最适pH值均正常。红细胞酶的同工酶模式正常，但所有分子形式的含量均减少。细胞老化过程中己糖激酶的衰减动力学也正常。己糖激酶缺陷细胞的葡萄糖消耗量为对照组的60-65%，而通过磷酸戊糖途径代谢的量未改变。先证者的红细胞2,3-二磷酸甘油酸和葡萄糖-6-磷酸水平正常，但其父母的红细胞中这些指标降低，其父母为该缺陷的杂合子，但血液学数据正常。与之前报道的13例己糖激酶缺乏症病例进行比较，证实了这种疾病具有广泛的表型变异性。
