Effect of hydrogenation of glucosyl- and galactosylceramide on their enzymatic hydrolysis.
Effect of hydrogenation of glucosyl- and galactosylceramide on their enzymatic hydrolysis.
复制标题
葡萄糖基神经酰胺和半乳糖神经酰胺的氢化对其酶水解的影响。
DOI：
10.1016/0009-8981(83)90347-9
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发表时间：
1983
期刊：
影响因子：
--
通讯作者：
Suzuki,K
中科院分区：
文献类型：
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作者：
Vaccaro,AM;Muscillo,M;Suzuki,K
我们早期观察到，N-硬脂酰-和N-二十四烷酰-葡糖基-二氢鞘氨醇对水解酶葡糖神经酰胺酶的亲和力比葡糖神经酰胺的天然混合物低得多[11]，这一观察结果已进一步用催化氢化的天然底物进行了研究。对不同结构的半乳糖神经酰胺酶的水解也进行了类似的实验。氢化过程使脂肪酸和长链碱部分完全饱和。对于任一种酶，氢化的天然底物的亲和力约为未处理的天然底物混合物的一半。然而，含有单一饱和脂肪酸和二氢鞘氨醇的合成葡糖神经酰胺的亲和力通常仍低于氢化天然混合物。当两种不同脂肪酸的合成底物混合在一起时，对酶的亲和力增加到比单独的合成底物高得多的水平，并达到氢化天然底物混合物的水平。半乳糖基神经酰胺水解的研究结果是相似的，除了合成底物与硬脂酸棕榈酸的酶的亲和力不低于氢化的天然底物混合物。当测定混合物的其他成分（如缓冲液和洗涤剂）变化时，不同结构对其酶水解的影响保持相似。
Our earlier observation thatN-stearoyl- andN-lignoceroyl-glucosyl-dihydrosphingosines have much lower affinity to the hydrolytic enzyme, glucosylceramidase, than the natural mixture of glucosylceramide [11] has been further pursued with catalytically hydrogenated natural substrate. Similar experiments were also carried out for hydrolysis of galactosylceramide of different structures by galactosylceramidase. The hydrogenation procedure completely saturated both fatty acid and long chain base moieties. For either enzyme, the hydrogenated natural substrate had affinity approximately half of the untreated natural substrate mixture. However, the synthetic glucosylceramides which contained a single saturated fatty acid and dihydrosphingosine had generally still lower affinity than the hydrogenated natural mixture. When two synthetic substrates of different fatty acids were mixed together, the affinity to the enzyme increased to a level much higher than that of either of the synthetic substrates alone and reached that of the hydrogenated natural substrate mixture. The findings were similar for galactosylceramide hydrolysis except that the synthetic substrate with palmitic of stearic acid had affinity to the enzyme not much lower than that of the hydrogenated natural substrate mixture. These effects of different structures on their enzymatic hydrolysis remained similar when other constituents of the assay mixture, such as the buffer and detergents, were varied.