This family represents N-terminal domain of a group of neutral/alkaline ceramidases found in both bacteria and eukaryotes [1,2,3]. The EC classification is EC:3.5.1.23. The enzyme hydrolyses ceramide to generate sphingosine and fatty acid. The enzyme plays a regulatory role in a variety of physiological events in eukaryotes and also functions as an exotoxin in particular bacteria. This N-terminal domain carries two metal-binding sites, the first for Zn2+ residing within the domain, and the second, for Mg2+/Ca2+ lying at the interface between the two domains [4].

1: Molecular cloning of the full-length cDNA encoding mouse neutral ceramidase. A novel but highly conserved gene family of neutral/alkaline ceramidases. Tani M, Okino N, Mori K, Tanigawa T, Izu H, Ito M; J Biol Chem 2000;275:11229-11234. PMID:10753931

2: Molecular cloning and characterization of a human mitochondrial ceramidase. El Bawab S, Roddy P, Qian T, Bielawska A, Lemasters JJ, Hannun YA; J Biol Chem 2000;275:21508-21513. PMID:10781606

3: Molecular cloning, sequencing, and expression of the gene encoding alkaline ceramidase from Pseudomonas aeruginosa. Cloning of a ceramidase homologue from Mycobacterium tuberculosis. Okino N, Ichinose S, Omori A, Imayama S, Nakamura T, Ito M; J Biol Chem 1999;274:36616-36622. PMID:10593963

4: Mechanistic insights into the hydrolysis and synthesis of ceramide by neutral ceramidase. Inoue T, Okino N, Kakuta Y, Hijikata A, Okano H, Goda HM, Tani M, Sueyoshi N, Kambayashi K, Matsumura H, Kai Y, Ito M; J Biol Chem. 2009;284:9566-9577. PMID:19088069