PathwayStep1992 PathwayStep1993 PathwayStep1994 PathwayStep1995 PathwayStep1996 PathwayStep1997 PathwayStep1998 PathwayStep1999 Neu5Ac is cleaved from GM3 by NEU1 and 4 to form a globoside (lysosomal lumen) Hexosaminidase A cleaves GalNAc from GM2 to form GM3 Ganglioside GM2 activator presents GM2 to hexosaminidase for cleavage Beta-galactosidase hydrolyses GM1 to GM2 Alpha-galactosidase A removes a terminal galactose from alpha-D-galactoside oligomers SUMF1 mediates the oxidation of cysteine to formylglycine, producing active arylsulfatases Beta-galactosidase can also hydrolyse globosides to form cerebrosides Both hexosaminidase A and B can cleave GalNAc from globoside Active ARSA translocates to the lysosome Sphingomyelin phosphodiesterase 2 and 3 (SMPD2 and 3) hydrolyse sphingomyelin to ceramide (plasma membrane) Sphingomyelin phosphodiesterase (SMPD1) hydrolyses sphingomyelin to ceramide (lysosome) Glucosylceramidase cleaves the glucosidic bond of glucocerebroside to form ceramide Sphingomyelin phosphodiesterase 4 (SMPD4) hydrolyses sphingomyelin to ceramide (ER membrane) Galactocerebrosidase cleaves the galactosyl bond of galactocerebroside to form ceramide Arylsulfatase A hydrolyses sulfate from sulfatide to form cerebroside Glucosylceramidase 2 cleaves the glucosidic bond of glucocerebroside to form ceramide (plasma membrane) Glucosylceramidase 3 cleaves the glucosidic bond of glucocerebroside to form ceramide (cytosol) Acid ceramidase hydrolyses ceramide into sphingosine and free fatty acid (lysosome) Ectonucleotide pyrophosphatase/phosphodiesterase 7 (ENPP7) hydrolyses sphingomyelin Galactosylceramide sulfotransferase (GAL3ST1) mediates the sulfation of membrane glycolipids Ceramide kinase (CERK) mediates the phosphorylation of ceramide Ceramide glucosyltransferase (UGCG) catalyses the transfer of glucose to ceramide Steryl sulfatase hydrolyses sulfate from steroid sulfates Neutral ceramidase hydrolyses ceramide into sphingosine and free fatty acid (plasma membrane) Neu5Ac is cleaved from GM3 by NEU3 to form globoside (plasma membrane) Neu5Ac is cleaved from GM3 by NEU2 to form a globoside (cytosol) PathwayStep2000 PathwayStep2001 PathwayStep2002 PathwayStep2016 PathwayStep2017 PathwayStep2014 PathwayStep2015 PathwayStep2003 PathwayStep2004 PathwayStep2005 PathwayStep2006 PathwayStep2007 PathwayStep2008 PathwayStep2009 PathwayStep2011 PathwayStep2010 PathwayStep2013 PathwayStep2012 Glycosphingolipid metabolism Authored: Jassal, B, 2011-10-14 Edited: Jassal, B, 2011-10-14 GENE ONTOLOGYGO:0006687 Pubmed20919643 Reactome Database ID Release 431660662 Reactome, http://www.reactome.org ReactomeREACT_116105 Reviewed: Stephan, R, 2011-10-31 The steps involved in the synthesis of glycosphingolipids (sphingolipids with one or more sugars attached) are annotated here (Gault et al. 2010).