| Autor: |
Deeva AA; Biophysics Department, Siberian Federal University, 660041 Krasnoyarsk, Russia., Lisitsa AE; Biophysics Department, Siberian Federal University, 660041 Krasnoyarsk, Russia., Sukovatyi LA; Biophysics Department, Siberian Federal University, 660041 Krasnoyarsk, Russia., Melnik TN; Institute of Protein Research, Russian Academy of Sciences, 142290 Pushchino, Russia., Kratasyuk VA; Biophysics Department, Siberian Federal University, 660041 Krasnoyarsk, Russia.; Institute of Biophysics, Siberian Branch of Russian Academy of Sciences, 660036 Krasnoyarsk, Russia., Nemtseva EV; Biophysics Department, Siberian Federal University, 660041 Krasnoyarsk, Russia.; Institute of Biophysics, Siberian Branch of Russian Academy of Sciences, 660036 Krasnoyarsk, Russia. |
| Abstrakt: |
The evaluation of temperature effects on the structure and function of enzymes is necessary to understand the mechanisms underlying their adaptation to a constantly changing environment. In the current study, we investigated the influence of temperature variation on the activity, structural dynamics, thermal inactivation and denaturation of Photobacterium leiognathi and Vibrio harveyi luciferases belonging to different subfamilies, as well as the role of sucrose in maintaining the enzymes functioning and stability. We used the stopped-flow technique, differential scanning calorimetry and molecular dynamics to study the activity, inactivation rate, denaturation and structural features of the enzymes under various temperatures. It was found that P. leiognathi luciferase resembles the properties of cold-adapted enzymes with high activity in a narrow temperature range and slightly lower thermal stability than V. harveyi luciferase, which is less active, but more thermostable. Differences in activity at the studied temperatures can be associated with the peculiarities of the mobile loop conformational changes. The presence of sucrose does not provide an advantage in activity but increases the stability of the enzymes. Differential scanning calorimetry experiments showed that luciferases probably follow different denaturation schemes. |
