Mouse Sphingosine kinase 1 (GenBank Accession No. AF415213), full length with N-terminal His tag, expressed in a Baculovirus infected Sf9 cell expression system. Specific Activity: 20 U/ug. Sphingosine kinase activity was determined using D-erythrosphingosine and ATP as substrates. A unit of sphingosine kinase activity is defined as the amount of enzyme required to produce 1pmol of S1P/min. Assay Buffer: 50mM HEPES, pH 7.4, 150mM sodium chloride, 5mM MgCl2, 1mM DTT, 3uM Na-orthovanadate, 0.5mM ATP, 4uM D-erythrosphingosine, and 0.1-0.5ug/ml sphingosine kinase 1. Applications: Useful for the study of enzyme kinetics, screening inhibitors, and selectivity profiling. Recommended Dilution: Optimal dilutions to be determined by the researcher. Storage and Stability: Aliquot to avoid repeated freezing and thawing and store at -70C. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap. Aliquots are stable for at least 6 months.