Increased thermal stability of luciferase of lighting beetles Luciola mingrelica by random mutagenesis

Luciferase of lighting bugs finds wide application in a number of fields in biotechnology and molecular biology, but use of luciferase is often limited by its fast inactivation at elevated temperatures. As a result of four sequential cycles of random mutagenesis, we obtained a mutant of luciferase of Luciola mingrelica lighting bugs with a considerably higher thermal stability. The obtained amino acid substitutions also resulted in an increase in the specific activity and a decrease in the Michaelis constant in terms of ATP by eight times, which evidences higher catalytic activity of the mutant. It is shown that using a random mutant is a highly efficient approach to increase the stability of luciferase.