Luciferase from Photinus pyralis (firefly) 

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.

Supplied as a solution in 50 mM Tris HCl pH 8.0, 1 mM dithiothreitol_, 1 mM EDTA, and 10% (v/v) glycerol.

The reaction of this enzyme with luciferin, ATP, and O₂ results in the emission of light. Luciferase can be used to detect trace amounts of ATP. Firefly luciferase is also 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.

expressed in Escherichia coli

mol wt 120 kDa (two non-identical subunits, each containing four free thiol groups, one of which is necessary for activity)

dry ice

−70°C

Stanley, P.E., A review of bioluminescent ATP techniques in rapid microbiology. J. Biolumin. Chemilumin. 4, 375, (1989)

Chappelle, E.W., et al., Determination of bacterial content in fluids,. Meth. Enzymol. 57, 65-72, (1978)

Rajgopal, S., and Vijayalakshmi, M.A. Enzyme Microb. Technol. 6, 482-489, (1984)

Kricka, L.J., Clinical and biochemical applications of luciferases and luciferins. Anal. Biochem. 175, 14-21, (1988)

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