GENETIC-EVIDENCE FOR TRANSMEMBRANE ACETYLATION BY LYSOSOMES
GENETIC-EVIDENCE FOR TRANSMEMBRANE ACETYLATION BY LYSOSOMES
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DOI：
10.1126/science.3090688
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发表时间：
1986-09-05
期刊：
影响因子：
56.9
通讯作者：
ROME, LH
中科院分区：
文献类型：
--
作者：
BAME, KJ;ROME, LH
乙酰辅酶A：α-氨基葡糖苷N-乙酰转移酶是一种在遗传性疾病C型桑菲力波病中缺乏的溶酶体膜酶。所述酶催化乙酰基从细胞质乙酰辅酶A（乙酰辅酶A）转移到末端α-乙酰辅酶A。硫酸乙酰肝素在细胞器内的葡糖胺残基。以前的动力学实验表明，该酶通过乒乓机制进行跨膜乙酰化;因此，该反应可以分为两个半反应-酶的乙酰化和乙酰基转移到葡糖胺。发现来自患者的细胞在执行每个半反应的能力方面有所不同。五个细胞系（来自三个家庭）能够催化乙酰化的溶酶体膜，并进行乙酰辅酶A/辅酶A交换，而第六个细胞系是缺乏这种活性。
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.