Shrimp alkaline phosphatase (SAP) nonspecifically catalyzes the dephosphorylation of 5"-termini DNA and RNA phosphomonoesters, but does not degrade diphosphate or triphosphate linkages. The enzyme acts on 5" protruding, recessive, and blunt5"-termini. Unlike Calf intestinal alkaline phosphatase, SAP is irreversibly heat inactivated at 65°C for 15 minutes, allowing for streamlining of cloning experiments.