Stabilization of firefly luciferase against thermal stress by osmolytes.
The effects of osmolytes, including sucrose, sorbitol and proline on the remaining activity of firefly luciferase were measured. Heat inactivation studies showed that these osmolytes maintain the remaining activity of enzyme and increase activation energy of thermal unfolding reaction. Fluorescence and circular dichroism (CD) experiments showed changes in secondary and tertiary structure of firefly luciferase, in the presence of sucrose, sorbitol and proline. The unfolding curves of luciferase (obtained by far-UV CD spectra), indicated an irreversible thermal denaturation and raising of the midpoint of the unfolding transition temperature (T(m)) in the presence of osmolytes.
Mehrabi
Maryam
M
Department of Biochemistry, Faculty of Basic Sciences, Tarbiat Modares University, Tehran, Iran.
Hosseinkhani
Saman
S
Ghobadi
Sirous
S
D000818:Animals; D002942:Circular Dichroism; D048888:Fireflies / Q000201:enzymology*; D006358:Hot Temperature; D049409:Luciferases, Firefly / Q000302:isolation & purification / Q000378:metabolism*; D009997:Osmotic Pressure; D011392:Proline; D011487:Protein Conformation; D013012:Sorbitol; D013050:Spectrometry, Fluorescence; D013395:Sucrose
D013012:Sorbitol; D013395:Sucrose; D011392:Proline; D049409:Luciferases, Firefly