Native Shrimp Alkaline Phosphatase (nSAP)
Native Shrimp alkaline phosphatase is a well-proven tool for DNA or nucleotide dephosphorylation. It has been known as a hassle-free alternative to other alkaline phosphatases. The product has now been replaced by a recombinant version. Native SAP may, however, still be available in bulk quantities.
Origin
Native Shrimp Alkaline Phosphatase (nSAP) is derived from Arctic Shrimp, a marine organism that thrives in the cold arctic environment. Arctic Shrimps (Pandalus borealis) are caught by trawlers in the areas around Svalbard (Spitsbergen) as far north as the 78th latitude, not far from the polar ice cap. In these areas the sea temperature rarely exceeds 5°C, truly a cold environment.
Shrimps are frozen aboard the trawlers, and brought to shrimp processing plants in Northern Norway. At the time of processing, the first step is to thaw the frozen shrimp blocks under circulating water. This thawing process works also as a gentle extraction process for shrimp enzymes. For this reason, shrimp thawing water is collected by ArcticZymes AS and brought to our processing plant in Tromsø for purification.
We have developed an extensive purification process that through filtration, extraction and chromatography yields a final product suitable for use in research and diagnostics applications. This product has been on the market since 1993, and is still one of the reference and standard enzymes in the DNA researcher’s toolbox.
Specifications
Unit definition: One Unit will convert 1 µmol of p-nitrophenyl phosphate per minute to nitrophenol and phosphate at 37°C and pH 10.4 in 0.1 M glycine buffer, 1 mM each of ZnCl2 and MgCl2.
Specific activity: >2 000 Units/mg.
Purity: Purified to apparent homogeneity by SDS-PAGE. DNase, RNase or protease activities not detected.
Concentration: Minimum 10 000 Units/ml.
Properties
Stability: Stable at -20°C in storage buffer (25 mM Tris-HCl pH 7.6, 1 mM MgCl2, 0.1 mM ZnCl2, glycerol 50 %). At 4°C, 70% activity remains after 15 days. At room temperature, 60% activity remains after 96 hours. SAP is completely inactivated after 5 minutes at 65°C. In a standard thermocycler, the process of heating from 37 to 95°C and back to 37°C is sufficient to completely inactivate SAP.