Ceramidases neutral

Ceramidases are enzymes that cleave the N-acyl linkage of Cer into SPH and free fatty acid. They are an emerging class of enzymes composed of multiple isoforms. Historically, these isoforms have been classified as acid, neutral or alkaline, based on the pH optimum of their activities although some isoforms show activity in a broad range. With the recent cloning of several isoforms from yeast, bacteria, and mammals, a genetical distinction and classification of these enzymes can now be employed. 

Tani, M., Okino, N., Mitsutake, S., Tanigawa, T, Izu, H., and Ito, M., 2000a, Purification and characterization of a neutral ceramidase from mouse fiver. A single protein catalyzes the reversible reaction in which ceramide is both hydrolyzed and synthesized. J. Biol. Chem. 275 3462-3468. 

Tani, M., OMno, N., Mori, K., Tatiigawa, T., Izu, H. and Ito, M., 2000, Molecular cloning of the fuU-length cDNA encoding mouse neutral ceramidase. A novel but highly conserved gene family of neutral/alkaline ceramidases,/. Biol. Chem. 275 11229-11234. 

A nonlysosomal ceramidase in some tissues functions optimally at neutral or alkaline pH and participates in the synthesis and breakdown of ceramide. Deficiency of lysosomal (acid) ceramidase in Farber s disease (lipogranu-lomatosis) causes accumulation of ceramide. The disease is inherited as an autosomal recessive trait and is characterized by granulomatous lesions in the skin, joints, and larynx and moderate nervous system dysfunction it may also involve heart, lungs, and lymph nodes. It is usually fatal during the first few years of life. 

SM Precursor of ceramide Acid/neutral/alkaline ceramidase enzymatic activity ... 

D-MAPP Neutral/ Alkaline ceramidase inhibitor Squamous cell carcinoma... 

Additional ceramidases with neutral and alkaline pH optima have been found in various cell compartments (M. Tani, 2000, 2005) including mitochondria (El Bawab, 2000) and appear to be involved in signaling. A neutral ceramidase is expressed in human intestine and released into the intestinal lumen (L. Ohlsson, 2007), and mice lacking this... 

Franzen, R, Fabbro, D, Aschrafi, A, Pfeilschifter, J and Huwiler, A (2002) Nitric oxide induces degradation of the neutral ceramidase in rat renal mesangial cells and is counterregulated by protein kinase C. J Biol Chem, 211, 46184-46190. 

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