New temperature-switchable acyl homoserine lactone-regulated expression vector

Applied Microbiology and Biotechnology. 2023. No. 107. P. 807–818.

Sergey V. Bazhenov, Scheglova E., Utkina A., Anna A. Kudryavtseva, Al Ebrahim R., Ilya V. Manukhov

Bacterial expression systems play an indispensable role in the biosynthesis of recombinant proteins. Diferent proteins and the tasks associated with them may require diferent systems. The purpose of this work is to make an expression vector that allows switching on and of the expression of the target gene during cell incubation. Several expression vectors for use in Escherichia coli cells were developed using elements of the luxR/luxI type quorum sensing system of psychrophilic bacterium Aliivibrio logei. These vectors contain A. logei luxR2 and (optionally) luxI genes and LuxR2-regulated promoter, under the control of which a target gene is intended to be inserted. The synthesis of the target protein depends directly on the temperature: gene expression starts when the temperature drops to 22 °C and stops when it rises to 37 °C, which makes it possible to fx the desired amount of the target protein in the cell. At the same time, the expression of the target gene at a low temperature depends on the concentration of the autoinducer (L-homoserine N-(3-oxohexanoyl)-lactone, AI) in the culture medium in a wide range from 1 nM to 10 μM, which makes it possible to smoothly regulate the rate of target protein synthesis. Presence of luxI in the vector provides the possibility of autoinduction. Constructed expression vectors were tested with gfp, ardA, and ardB genes. At maximum, we obtained the target protein in an amount of up to 33% of the total cellular protein.

Keywords: генетическая инженерия, genetic engineering, Escherichia coli, Escherichia coli, Aliivibrio logei, Aliivibrio logei, expression vector, Экспрессионный вектор