A heat labile alkaline phosphatase enzyme and methods of using the same and kits including the same are disclosed. Specifically, a nucleotide sequence of, peptide sequence of, methods of using, and kits comprising, a heat labile alkaline phosphatase isolated from Colwellia psychrerythraea are provided. Methods of over-expression and purification of the recombinant alkaline phosphatase and mutants thereof are also disclosed. Methods of over-expressing and purifying commercially useful quantities of active recombinant heat labile alkaline phosphatase fusion enzymes from C. psychrerythraea, wherein the fusion enzymes comprise one or more heterologous leader sequences are disclosed. The disclosed C. psychrerythraea heat labile alkaline phosphatase has properties similar to shrimp alkaline phosphatase and can be substituted for shrimp alkaline phosphatase in assays involving the same.