[Genetic systems of biodegradation: organization and regulation of expression].

: The review discusses the current state of genetic analysis of degradative processes. Attention is mainly given to the structural and functional organization of the plasmid systems of degradation of organic compounds in gram-negative bacteria. The data available on the regulation mechanisms of D plasmids' metabolic operons, based on the most studied models of xyl and nah operons, are critically analyzed. The problems of evolution of plasmid D systems are considered conceptually as well as the principles of the experimental strategy of developing new metabolic pathways under laboratory conditions. The prospects of constructing the strains capable of efficient degradation of xenobiotics are considered in brief.