Abstract: A Heike firefly luciferase having excellent thermostability and storage stability and a process for its production, wherein the amino acid corresponding to position 287 of Heike firefly luciferase is alanine.

Abstract: A firefly luciferase having the amino acid sequence of firefly luciferase, wherein the amino acid corresponding to position 287 of Heike firefly luciferase is replaced with alanine, or wherein the amino acid corresponding to position 392 is replaced with isoleucine. The firefly luciferase has improved thermostability and storage stability. A firefly luciferase gene coding for the firefly luciferase. By utilizing this gene, it is possible to efficiently produce firefly luciferase with increased stability. It is also possible to obtain firefly luciferase with further increased stability by combination with a mutation in which the amino acid at position 326 is replaced with serine, and/or a mutation in which the amino acid at position 467 is replaced with isoleucine.

Abstract: A composition for analyzing nucleic acid that contains luciferase for which reactivity to dATP is equal to or less than 1/400 reactivity to ATP. A method for analyzing nucleic acid that comprises the use of the composition. A kit for analyzing nucleic acid comprising the composition. The method provides for an inexpensive, highly accurate and highly sensitive nucleic acid analysis that uses dATP instead of an expensive reagent having a low reactivity to DNA polymerase.

Abstract: The present invention provides a firefly luciferase for inexpensive, highly accurate and highly sensitive nucleic acid analysis that uses dATP instead of an expensive reagent having low reactivity to DNA polymerase in the manner of dATP?S, a method of analyzing nucleic acid that uses that luciferase, and a kit for analyzing nucleic acid thereof. The present invention relates to a composition for analyzing nucleic acid that contains luciferase for which reactivity to dATP is equal to or less than 1/400 reactivity to ATP, a method of analyzing nucleic acid that comprises the use of that composition, and a kit for analyzing nucleic acid comprising that composition.

Abstract: The present invention provides a firefly luciferase for inexpensive, highly accurate and highly sensitive nucleic acid analysis that uses dATP instead of an expensive reagent having low reactivity to DNA polymerase in the manner of dATP?S, a method of analyzing nucleic acid that uses that luciferase, and a kit for analyzing nucleic acid thereof. The present invention relates to a composition for analyzing nucleic acid that contains luciferase for which reactivity to dATP is equal to or less than 1/400 reactivity to ATP, a method of analyzing nucleic acid that comprises the use of that composition, and a kit for analyzing nucleic acid comprising that composition.