Perfection of biological organization and mechanisms of stress resistance of Rhodococcus sensu stricto

Abstract

Among microorganisms of contaminated environments, the so-called stress-tolerants, a special place belongs to bacteria of the genus Rhodococcus (class Actinomycetes, order Mycobacteriales, family Nocardiaceae), which are able to effectively withstand a wide range of stress effects against the backdrop of a sharp decrease in the quality of the natural environment. Rhodococci possessing a complex of strategic survival techniques occupy a dominant position in the biocenoses of anthropogenically loaded soil and aquatic ecosystems. The paper considers a set of basic biological properties of extremotolerant Rhodococcus spp. and studies the responses of Rhodococci triggered by the presence of ecotoxicants. The information obtained as a result of long-term research into the biodiversity of Rhodococcus, as biodegrader of complex organic compounds, as well as the influence of Rhodococcus on the processes of natural restoration of oil-contaminated ecosystems, is presented. Particular attention is paid to the spectrum of relatively universal features and characteristics of Rhodococcus under conditions of induction of enzyme oxygenase complex, as well as to new facts about the interaction of Rhodococcus with foreign compounds and a variety of complementary
mechanisms of protection from environmental stresses. The obtained data provide an understanding of the role of Rhodococcus in the functioning of the biosphere, purification or reduction of toxic components under conditions of environmental destabilization. This creates preconditions and additional opportunities for the development and implementation of more advanced ecobiotechnologies for environmental purification, neutralization, or effective use of waste arising in the course of industrial production. Observing the ability of these smart bacteria to endure stressful situations, one cannot help but admire how the relative simplicity of Rhodococcus structure is harmoniously combined with the amazing perfection of their biological organization and their ability to form a variety of defensive tactics and offensive strategies to maintain an environmental competitive advantage.