title: A GM2-specific beta-hexosaminidase from the roe of striped mullet (Mugil cephalus).
abstract: The roe of striped mullet (Mugil cephalus) was found to contain a beta-hexosaminidase different from the beta-hexosaminidases isolated from other sources. The enzyme from mullet roe is able to cleave GalNAc from GM2 without the assistance of either an activator protein or a detergent. It also cleaves the oligosaccharide derived from GM2 and other oligosaccharides containing the GM2 sequence GalNAc beta 4(NeuAc alpha 3)Gal-. However, it is not effective in hydrolyzing neutral glycosphingolipids containing terminal GalNAc or GlcNAc, such as GbOse4Cer, GgOse3Cer, or LcOse3Cer. These results indicate that mullet roe beta-hexosaminidase can specifically cleave GalNAc from the glycoconjugates containing the GM2 sequence. No beta-hexosaminidase with such specificity has been previously described. Thus, this unique enzyme should be very useful for the detection and analysis of glycoconjugates containing the oligosaccharide chains with GM2 sequence.
mesh_terms: D000818:Animals; D002021:Buffers; D002855:Chromatography, Thin Layer; D005399:Fishes / Q000378:metabolism*; D005678:G(M2) Ganglioside / Q000378:metabolism*; D005732:Gangliosides / Q000378:metabolism*; D009844:Oligosaccharides / Q000378:metabolism; D009994:Osmolar Concentration; D001619:beta-N-Acetylhexosaminidases / Q000378:metabolism*
chemical_list: D002021:Buffers; D005732:Gangliosides; D009844:Oligosaccharides; D005678:G(M2) Ganglioside; D001619:beta-N-Acetylhexosaminidases