Amplite(TM) Fluorimetric Acidic Sphingomyelinase Assay Kit *Red Fluorescence*

Sphingomyelinase (SMase) is an enzyme that is responsible for cleaving sphingomyelin (SM) to phosphocholine and ceramide. Activation of SMases plays an important role in the cellular response such as regulation of cell growth, cell differentiation, cell cycle arrest and programmed cell death. Five types of sphingomyelinase (SMase) have been identified based on their cation dependence and pH optima of action, including lysosomal acid SMase, secreted zinc-dependent acid SMase, magnesium-dependent neutral SMase, magnesium-independent neutral SMase and alkaline SMase. Among them, the lysosomal acidic SMase and the magnesium-dependent neutral SMase are considered to be the major factors for the production of ceramide in cellular stress responses. Our Amplite(TM) Fluorimetric Acidic Sphingomyelinase Assay Kit provides one of the most sensitive methods for detecting acidic SMase activity or screening its inhibitors. The kit uses Amplite(TM) Red as a fluorogenic probe to indirectly quantify the phosphocholine produced from the hydrolysis of sphingomyelin (SM) by sphingomyelinase (SMase). It can be used for measuring the SMase activity in blood, cell extracts or other solutions. The fluorescence intensity of Amplite(TM) Red is proportional to the formation of phosphocholine, therefore to the SMase activity. The kit is an optimized 'mix and read' assay compatible with HTS liquid handling instruments.