Bame K J, Rome L H
Science. 1986 Sep 5;233(4768):1087-9. doi: 10.1126/science.3090688.
Acetyl-CoA:alpha-glucosaminide N-acetyltransferase is a lysosomal-membrane enzyme deficient in a genetic disorder, Sanfilippo disease type C. The enzyme catalyzes the transfer of an acetyl group from cytoplasmic acetyl-coenzyme A (acetyl-CoA) to terminal alpha-glucosamine residues of heparan sulfate within the organelle. Previous kinetic experiments indicated that the enzyme carries out a transmembrane acetylation via a ping-pong mechanism; the reaction can therefore be dissected into two half reactions--acetylation of the enzyme, and transfer of the acetyl group to glucosamine. Cells derived from patients were found to differ in their ability to perform each half reaction. Five cell lines (derived from three families) were able to catalyze acetylation of the lysosomal membrane and to carry out acetyl-CoA/CoA exchange, whereas a sixth cell line was devoid of this activity.
乙酰辅酶A：α-葡糖胺N-乙酰转移酶是一种溶酶体膜酶，在一种遗传性疾病——Ⅲ型Sanfilippo病中缺乏。该酶催化乙酰基从细胞质中的乙酰辅酶A（乙酰-CoA）转移至细胞器内硫酸乙酰肝素的末端α-葡糖胺残基上。先前的动力学实验表明，该酶通过乒乓机制进行跨膜乙酰化反应；因此，该反应可分为两个半反应——酶的乙酰化以及乙酰基向葡糖胺的转移。发现来自患者的细胞在进行每个半反应的能力上存在差异。五个细胞系（来自三个家族）能够催化溶酶体膜的乙酰化并进行乙酰-CoA/CoA交换，而第六个细胞系则缺乏这种活性。
