We report here the molecular cloning, expression and characterization of a novel endo-alpha-N-acetylgalactosaminidase, classified into the GH101 family, from Enterococcus faecalis (endo-EF). The recombinant endo-EF was found to catalyze the liberation of core1-disaccharides (Galbeta1-3GalNAc) from core1-pNP (Galbeta1-3GalNAcalpha-pNP) like other GH101 family enzymes. However, endo-EF seems to differ in specificity from the GH101 enzymes reported to date, because it was able to release trisaccharides from core2-pNP (Galbeta1-3[GlcNAcbeta1-6]GalNAcalpha-pNP) and tetrasaccharides from Gal-core2-pNP (Galbeta1-3[Galbeta1-3GlcNAcbeta1-6]GalNAcalpha-pNP). Interestingly, the enzyme could transfer not only core1-disaccharides but also core2-trisaccharides to alkanols generating alkyl-oligosaccharides. Endo-EF should facilitate O-glycoprotein research.

中文翻译：

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粪肠球菌的新型内切α-N-乙酰半乳糖苷酶的分子克隆，表达和表征。

我们在这里报告了从粪肠球菌（endo-EF）分类为GH101家族的新型内切α-N-乙酰半乳糖苷酶的分子克隆，表达和鉴定。像其他GH101家族酶一样，发现重组的end-EF能催化从core1-pNP（Galbeta1-3GalNAcalpha-pNP）释放core1-二糖（Galbeta1-3GalNAc）。但是，endo-EF的特异性似乎不同于迄今报道的GH101酶，因为它能够从core2-pNP（Galbeta1-3 [GlcNAcbeta1-6] GalNAcalpha-pNP）释放三糖和从Gal-core2-pNP释放四糖。 （Galbeta1-3 [Galbeta1-3GlcNAcbeta1-6] GalNAcalpha-pNP）。有趣的是，该酶不仅可以将core1-二糖转移，而且可以将core2-三糖转移到生成烷基寡糖的烷醇中。Endo-EF应该促进O-糖蛋白的研究。