Family C89


Summary Holotypes Alignment Tree Genomes Literature H-seq M-seq

Summary for family C89

Family type peptidaseC89.001 - acid ceramidase precursor (Homo sapiens), MEROPS Accession MER0100794 (peptidase unit: 137-389)
Content of familyPeptidase family C89 contains a self-cleaving precursor protein.
History Identifier created: MEROPS 8.2 (4 August 2008)
Acid ceramidase (EC is a lysosomal enzyme that is synthesized as a precursor and is activated by cleavage into alpha and beta chains. Hydrolysis has been shown to be an autocatalytic activity (Shtraizent et al., 2008). The mature ceramidase hydrolyses the sphingolipid ceramide to sphingosine and a free fatty acid (Park & Schuchman, 2006).
Catalytic typeCysteine
Active site residuesC137 R153 D156 
Active siteThe catalytic Cys (Cys143) has been identified by site-directed mutagenesis. Mutation of Arg159 and Asp162 also prevented autoprocessing (Shtraizent et al., 2008). It is not known whether Cys143 is also the active site residue responsible for ceramidase activity in the mature enzyme .
InhibitorsMethyl methanethiosulfonate has been shown to be inhibitory (Shtraizent et al., 2008).
Molecular structureAlthough no tertiary structure has been solved, the active site Cys is at the N-terminus of the beta chain, which is characteristic of N-terminal hydrolases of clan PB.
Distribution of family Bacteria details  
Archaea -  
Protozoa details  
Fungi details  
Plants details  
Animals details  
Viruses details  
Biological functions
Pharmaceutical and biotech relevanceDefects in the gene cause Farber lipogranulomatosis, an inherited lipid storage disease, which is fatal in early infancy and is characterized by lipid-filled nodules under the skin with extreme pain in the joints. Aberrant activity has also been detected in several human cancers and the enzyme may be a useful drug target (Park & Schuchman, 2006).
Statistics for family C89Sequences:691
Identifiers with PDB entries:0
Downloadable files Sequence library (FastA format)
Sequence alignment (FastA format)
Phylogenetic tree (Newick format)
Peptidases and Homologues MEROPS ID Structure
acid ceramidase precursorC89.001-
N-acylethanolamine acid amidase precursorC89.002-
F27E5.1 g.p. (Caenorhabditis elegans)C89.A01-
asah-1 g.p. (Caenorhabditis elegans)C89.A02-
family C89 non-peptidase homologuesnon-peptidase homologue-
family C89 unassigned peptidasesunassigned-