Viability and Ultrastructural Changes of Bacterial Cells Grown in the Presence of a Pollutant

Abstract

Microbial degradation of pollutants is a safe and cost-effective way to clean the environment. However, little is known on changes at the cell ultrastructure level and on the mechanisms of adaptation in general to xenobiotics under conditions of their biodegradation. Rhodococcus sp. strain 7Ba is capable of preserving long-term viability and the ability to degrade when growing with phenol at up to 1 g/L. Destructive morphological changes at the ultrastructural level were not detected in the cells growing on phenol, which indicated rapid adaptation to it. Strain 7Ba cells formed a polysaccharide matrix under all experimental conditions. Investigation of the growth of spore-forming bacteria cells on glyphosate (0.5 g/L) showed that, although the substrate was not optimal, the cells were able to grow on it. The cells of Paenibacillus sp. GP5-2 and Rossellomorea sp. GP5-7 exhibited ultrastructural changes and a delay in spore formation (for strain GP5-2). The detected changes were adaptive, and further study will improve our understanding of their strategy ensuring the preservation of survival and the ability to degrade.