KINETICS OF EXPRESSION OF LUCIFERASE GENES FROM THE FIREFLIES PHOTINUS-PYRALIS AND LUCIOLA-MINGRELICA IN ESCHERICHIA-COLI .1. KINETICS OF CONVERSION OF RECOMBINANT LUCIFERASES INTO ENZYMATICALLY ACTIVE CONFORMERS

The kinetics of expression of luciferase genes from the fireflies Phot inus pyralis and Luciola mingrelica on plasmids pME61 and pJG lambda, respectively, with the lambda P-R thermally inducible promoter in E. c oli CA cultures incubated according to temperature schemes of 28-42-21 degrees C or 28-21 degrees C was studied using three independent meth ods: 1) electrophoretic determination of the amount of luciferase; 2) enzyme immunoassay; 3) enzymatic activity. Electrophoresis showed that after 3 h of thermal induction (42 degrees C), the amount of lucifera se protein produced over 10 h by Ph. pyralis reaches 4.5%, and that pr oduced by L. mingrelica is 4.1% of the total cell protein. No increase in was observed on further incubation. Postinduction incubation of th e cells at 21 degrees C results in increases, after a prolonged period of induction (40-50 h), in the amount of the native conformer and luc iferase activity. Both variables reached their peaks in 50-60 h. The i ncrease in the enzymatic activity correlated with increasing ATP level s in the cells. This phenomenon of low-temperature induction of the en zymatic activity is explained by the transition of proteins into a cat alytically active form with a considerable delay in relation to the pr otein biosynthesis.