Relationship between stability and bioluminescence color of firefly luciferase.
Firefly luciferase catalyzes the oxidation of luciferin in the presence of ATP, Mg(2+) and molecular oxygen. The bioluminescence color of firefly luciferases is identified by the luciferase structure and assay conditions. Amongst different types of beetles, luciferase from Phrixotrix railroad worm (PhRE) with a unique additional residue (Arg353) naturally emits red bioluminescence color. By insertion of Arg356 in luciferase of Lampyris turkestanicus, corresponding to Arg353 in Phrixotrix hirtus, the color of the emitted light was changed to red. To understand the effect of this position on the bioluminescence color shift, four residues with similar sizes but different charges (Arg, Lys, Glu, and Gln) were inserted into Photinus pyralis luciferase. Comparison of mutants with native luciferase shows that mutation brought an increase in the content of secondary structure and globular compactness of (P. pylalis) luciferase. Comparative study of chemical denaturation of native and mutant luciferases by activity measurement, intrinsic and extrinsic fluorescence, circular dichroism, and DSC techniques revealed that insertion of positively charged residues (Arg, Lys) in the flexible loop (352-358) plays a significant role on the stability of (P. pyralis) luciferase and changes the light color to red.
Maghami
Parvaneh
P
Department of Biochemistry and Biophysics, Faculty of Biological Sciences, Tarbiat Modares University, P.O. Box 14115-175, Tehran, Iran.
Ranjbar
Bijan
B
Hosseinkhani
Saman
S
Ghasemi
Atiyeh
A
Moradi
Ali
A
Gill
Pooria
P
D000818:Animals; D002942:Circular Dichroism; D048888:Fireflies / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D015870:Gene Expression; D049409:Luciferases, Firefly / Q000737:chemistry* / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D049449:Luminescence; D009154:Mutation; D011489:Protein Denaturation; D055550:Protein Stability; D014508:Urea / Q000378:metabolism
D014508:Urea; D049409:Luciferases, Firefly