Adaptive mechanisms of alkanotrophic Rhodococci survival under unfavorable conditions

Cytobiochemical features of cells of the genus Rhodococcus actinobacteria under the nutritional shift from carbohydrate type to hydrocarbon one were characterized. Rhodococci cells were found to use different grouping strategies in colony populations, i.e. adhesion of cell wall peptidoglycane layers and formation of multiple cone-shaped offshoots on the cell wall surface. These allow rhodococci cells to "attach" to and survive in heterophasic natural habitats. Most typical reactions of rhodococci to gaseous and liquid n-alkanes were detected. Induction of rhodococci oxygenase complex resulted in overexpression of extracellular amino acids, thus the physiological role of this process was assumed. The alkanotrophic rhodococci adaptations observed in the study are considered as adaptive mechanisms of their survival under specific environmental conditions.