Institute of Molecular Biomembrane and Glycobiology, Tohoku Pharmaceutical University, Sendai, Japan.
Glycobiology. 2012 Jul;22(7):880-96. doi: 10.1093/glycob/cws057. Epub 2012 Feb 28.
Sialic acids are terminal acidic monosaccharides, which influence the chemical and biological features of glycoconjugates. Their removal catalyzed by a sialidase modulates various biological processes through change in conformation and creation or loss of binding sites of functional molecules. Sialidases exist widely in vertebrates and also in a variety of microorganisms. Recent research on mammalian sialidases has provided evidence for great importance of these enzymes in various cellular functions, including lysosomal catabolism, whereas microbial sialidases appear to play roles limited to nutrition and pathogenesis. Four types of mammalian sialidases have been identified and characterized to date, designated as NEU1, NEU2, NEU3 and NEU4. They are encoded by different genes and differ in major subcellular localization and enzymatic properties including substrate specificity, and each has been found to play a unique role depending on its particular properties. This review is an attempt to concisely summarize current knowledge concerning mammalian sialidases, with a special focus on their properties and physiological and pathological roles in cellular functions.
唾液酸是末端酸性单糖，影响糖缀合物的化学和生物学特性。唾液酸酶催化的唾液酸的去除通过构象的改变以及功能分子的结合位点的产生或丧失来调节各种生物学过程。唾液酸酶广泛存在于脊椎动物和各种微生物中。最近对哺乳动物唾液酸酶的研究为这些酶在各种细胞功能中的重要性提供了证据，包括溶酶体分解代谢，而微生物唾液酸酶的作用似乎仅限于营养和发病机制。迄今为止，已经鉴定和表征了四种类型的哺乳动物唾液酸酶，分别命名为 NEU1、NEU2、NEU3 和 NEU4。它们由不同的基因编码，在主要亚细胞定位和酶特性方面存在差异，包括底物特异性，并且每种酶都被发现根据其特定特性发挥独特的作用。这篇综述试图简明地总结目前关于哺乳动物唾液酸酶的知识，特别关注它们的特性以及在细胞功能中的生理和病理作用。
