An Enzyme Transfers Intact Oligosaccharides
Endo-M is one of the enzymes called endo-β-N-acetylglucosaminidases (endo-β-GlcNAc-ase). This enzyme was found by Yamamoto et al., in the culture fluid of Mucor hiemalis isolated from soil. Endo-M hydrolyzes an N,N-diacetylchitobiose moiety in oligosaccharides bound to the asparaginyl residue of various glycoproteins through the N-glucosidic linkage. The efficacy of this enzyme comes from the fact that one N-acetylglucosamine residue remains bound to the protein while cleaving the N,N-diacetylchitobiose moiety. The enzyme can thus transfer the intact oligosaccharide to suitable receptors.
Haneda et al. have transferred oligosaccharides to 9-fluorenylmethoxycarbonyl-asparaginyl-N-acetylglucosaminide [Fmoc-Asn(GlcNAc)] by incubating sialotransferrin glycopeptide, asialotransferrin glycopeptide and Man6GlcNAc2-Asn-peptide with Endo-M. Furthermore, synthetic hCG (β12-16)-GlcNAc-peptide has been subjected to transglycosylate of sialo complex type oligosaccharides. Inazu et al. have developed an alternative synthetic method for the peptide containing GlcNA. This method uses Fmoc-Asn(GlcNAc) synthesized from N-Fmoc aspartic acid (Fmoc-Asp-OH), and applied to a mixed acid anhydride method using dimethylphosphothioic acid (Mpt-MA), which generally shows poor responses toward hydroxyl groups. By combining this method with Endo-M, many glycopeptides can be designed and easily prepared. Yamamoto has compiled the outline of this methodology as the Chemo-Enzymatic Synthesis in his review. Endo-M can also be used to create new functions by introducing oligosaccharides to substances that originally do not have them. Unlike conventional endo-β-GlcNAc-ase, Endo-M is an enzyme with broad substrate specificity, cleaving not only high mannose type and hybrid type asparagines-linked oligosaccharides in glycoproteins but also performing the transglycosylation reaction of sialo complex type oligosaccharides, a reaction possible only using Endo-M. Therefore, Endo-M is expected to be applied to various fields.
- Endo-M (Recombinant : from Mucor hiemalis expressed in Candida boidinii)
[Purity : single band by SDS-PAGE (85KDa)]
- Purification and Characterization of a Novel Fungal Endo-β-N-acetylglucosaminidase Acting on Complex Oligosaccharides of Glycoproteins
- S. Kadowaki, K. Yamamoto, M. Fujisaki, K. Izumi, T. Tochikura, T. Yokoyama, Agric. Biol. Chem. 1990, 54, 97.
- Transglycosylation Activity of Mucor Hiemalis Endo-β-N-Acetylglucosaminidase Which Transfers Complex Oligosaccharides to the N-Acetylglucosamine Moieties of Peptides
- Transglycosylation of intact sialo complex-type oligosaccharides to the N-acetylglucosamine moieties of glycopeptides by Mucor hiemalis endo-β-N-acetylglucosaminidase
- A Synthesis of a Glycopeptide Analogue of Eel Calcitonin
- Chemo-enzymatic synthesis of bioactive glycopeptide using microbial endoglycosidase
- Ruthenium complexes carrying a disialo complex-type oligosaccharide: enzymatic synthesis and its application to a luminescent probe to detect influenza viruses