[Genetic control of plasmid recombination in the cotransformation of Saccharomyces cerevisiae: the role of RAD52 and FLP genes].

In our earlier works we observed high frequency of recombination between two chimeric plasmids of different types, when they were introduced into yeast cells via cotransformation. Incapability of one of these plasmids to replicate autonomously in yeast cell is the necessary condition for such recombination. The high efficiency of this process point to the differences between interplasmid recombination and other types of yeast recombination. In this work, we studied the participation of two genes in the control of interplasmid exchanges. These are RAD52 responsible for normal processes of meiotic and mitotic recombination and highly specific gene FLP located on 2 mkm DNA which specifies site-specific recombination in the region of inverted sequences of this plasmid. The mutation rad52 in the recipient strain was shown to sharply decrease the efficiency of recombination between integrative and episome plasmids during cotransformation. The absence of FLP gene in the recipient strain (cirO) has no influence on this process.