Substrate specificity of α2↔3‐sialyltransferases in ganglioside biosynthesis of rat liver golgi*
Substrate specificity of α2↔3‐sialyltransferases in ganglioside biosynthesis of rat liver golgi*
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大鼠肝脏高尔基体神经节苷脂生物合成中α2↔3-唾液酸转移酶的底物特异性*
DOI：
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发表时间：
1991
期刊：
影响因子：
--
通讯作者：
K. Sandhoff
中科院分区：
文献类型：
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作者：
H. Iber;G. Echten;K. Sandhoff
在源自大鼠肝脏的高尔基体囊泡中研究了参与神经节苷脂生物合成的四种唾液酸转移酶（I、II、IV 和 V）的受体特异性。这些唾液酸转移酶的活性强烈依赖于去污剂。使用 LacCer (Galβ14Glcβ11 Cer)、GM1a [Galβ13GalNAcβ14(NeuAcα23)Galβ14Glcβ11 Cer] 和 GD1b [Galβ13GalNAcβ14(NeuAcα28NeuAcα23)Galβ14Glcβ1 1 Cer] 作为底物和相互之间进行不同洗涤剂浓度的竞争实验神经节苷脂唾液酸转移酶活性抑制剂表明，唾液酸转移酶 IV 能够催化与 LacCer 以及 GM1a 和 GD1b 的半乳糖残基连接的 α23 中的唾液酸转移。其他三种唾液酸转移酶（I、II 和 V）似乎对其各自的糖脂受体 LacCer、GM3 和 GM1b、GD1a 和 GT1b 具有相当的特异性。此外，动力学数据表明，唾液酸转移酶 I 在较高的去垢剂浓度（> 75 μg Triton CF-54）下失活；在这些条件下，GM3和GD1a的形成仅由唾液酸转移酶IV催化。这些结果已被整合到神经节苷脂生物合成及其调控模型中。
The acceptor specificities of four sialyltransferases (I, II, IV and V) involved in ganglioside biosynthesis were studied in Golgi vesicles derived from rat liver. The activities of these sialyltransferases were strongly detergent-dependent. Competition experiments with different detergent concentrations using LacCer (Galβ14Glcβ11 Cer), GM1a [Galβ13GalNAcβ14(NeuAcα23)Galβ14Glcβ11 Cer] and GD1b [Galβ13GalNAcβ14(NeuAcα28NeuAcα23)Galβ14Glcβ1 1 Cer] as substrates, and as mutual inhibitors for ganglioside sialyltransferase activity, suggested that sialyltransferase IV was able to catalyze the sialyltransfer in α23 linkage to the galactose residues of LacCer as well as of GM1a and GD1b. The other three sialyltransferases (I, II and V) seemed to be quite specific for their respective glycolipid acceptors, LacCer, GM3 and GM1b, GD1a and GT1b. Furthermore the kinetic data showed that sialyltransferase I was inactive at higher detergent concentrations (> 75 μg Triton CF-54); under these conditions, formation of GM3 and GD1a was catalyzed only by sialyltransferase IV. These results have been integrated into a model for ganglioside biosynthesis and its regulation.
大鼠肝脏中的神经节苷脂生物合成：胞苷-5-单磷酸-n-乙酰神经氨酸：苏木精（GM3）唾液酸转移酶的表征。
DOI：
10.1016/0005-2760(80)90080-6
发表时间：
1980
期刊：
Biochimica et biophysica acta
影响因子：
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作者：
Eppler,CM;Morré,DJ;Keenan,TW
通讯作者：
Keenan,TW