荧光素酶 来源于北美萤火虫 （萤火虫）

Firefly luciferase is an enzyme that catalyzes production of light from luciferin in the presence of Mg²⁺-ATP and oxygen. The reaction of this enzyme with luciferin, ATP, and O₂ results in the emission of light.

This enzyme has wide range of applications in biotechnology and development of biosensors. Luciferase can be used to detect trace amounts of ATP and is one of the most commonly utilized reporter genes for the study of gene expression. The bioluminescent reaction catalyzed by luciferase is one of the most sensitive analytical tools for measuring gene expression. Less than or equal to one femtomole of ATP can be detected using 0.2 μg of luciferase. This enzyme has been used in a study to identify the different characteristics of reporter genes in whole-cell bacterial sensors. Luciferase from Photinus pyralis has also been used in a study to develop a novel bioluminogenic assay for α-chymotrypsin.

Luciferase activity can be inhibited by general anesthetics including isoflurane and ketamine/medetomidine thereby affecting the sensitivity of bioluminescence imaging.

Sold on the basis of protein content

Lyophilized powder approximately 20% protein; balance is primarily NaCl, HEPES buffer salts, and carbohydrate.

Chromatographically prepared and crystallized.

Note: Prior to 1991, a unit of firefly luciferase activity was defined as that amount which will produce 1.0 nanomole of pyrophosphate per minute at pH 7.7, 25 °C, using a system containing 0.6 mM ATP and 0.1 mM D-luciferin. The former nanomolar unit is equivalent to approximately 1.3 x 10⁶ light units.

Two contaminant, ATP-consuming activities are assayed for in this product, ATPase and nucleoside diphosphokinase. These impurities are found to be less than 5 nanomolar units/mg protein and less than 20 nanomolar units/mg protein, respectively.

Arsenate free.

Firefly luciferase is also available in economical recombinant forms (Product Numbers SRE0045 and L9420)

One light unit produces a biometer peak height equivalent to 0.02 μCi of ¹⁴C in PPO/POPOP cocktail. Light units measured in 50 μl assay mixture containing 5 pmol ATP and 7.5 nmol luciferin in Tris-glycine buffer, pH 7.6, at 25 °C.