Response Mechanisms of Bacterial Degraders to Environmental Contaminants on the Level of Cell Walls and Cytoplasmic Membrane

Abstract

Bacterial strains living in the environment must cope with the toxic compounds originating from humans production. Surface bacterial structures, cell wall and cytoplasmic membrane, surround each bacterial cell and create selective barriers between the cell interior and the outside world. They are a first site of contact between the cell and toxic compounds. Organic pollutants are able to penetrate into cytoplasmic membrane and affect membrane physiological functions. Bacteria had to evolve adaptation mechanisms to counteract the damage originated from toxic contaminants and to prevent their accumulation in cell. This review deals with various adaptation mechanisms of bacterial cell concerning primarily the changes in cytoplasmic membrane and cell wall. Cell adaptation maintains the membrane fluidity status and ratio between bilayer/nonbilayer phospholipids as well as the efflux of toxic compounds, protein repair mechanisms, and degradation of contaminants. Low energy consumption of cell adaptation is required to provide other physiological functions. Bacteria able to survive in toxic environment could help us to clean contaminated areas when they are used in bioremediation technologies.

Highly Solvent Tolerance in Serratia marcescens IBBPo15

“…The leakage of DNA macromolecules was previously described 14 for the bacterial cells grown in the presence of toxic organic solvents. Bacterial cells try to undertake proper responses to reduce the disruptive effect of organic compounds by readjustment of membrane fluidity 3 . The release of nucleic acids from S. marcescens IBB Po15 control cells and cells exposed to 5% organic solvents was investigated by measuring the absorbance of cell-free culture broths at 260 nm.…”

“…No significant changes were observed in the proteins profile of the cells exposed to n-decane which seemed to be less toxic for this bacterium. Toxic organic solvents usually affect the cell proteome 3 . Because under nutrient limitation conditions damaged proteins cannot be replaced with the newly synthesized, the proteome repair is required to maintain cell vitality.…”

“…Bacterial strains living in the polluted environments must cope with the toxic compounds (e.g., organic solvents) which result from humans activity. Surface bacterial structures, cell wall and cytoplasmic membrane, surround each bacterial cell and create selective barriers between the cell interior and the outside of the cell 3 . They are the first site of contact between the cell and toxic compounds which are able to penetrate into cytoplasmic membrane and affect the membrane functions 3,4 .…”

“…Surface bacterial structures, cell wall and cytoplasmic membrane, surround each bacterial cell and create selective barriers between the cell interior and the outside of the cell 3 . They are the first site of contact between the cell and toxic compounds which are able to penetrate into cytoplasmic membrane and affect the membrane functions 3,4 . Therefore, bacteria developed adaptation mechanisms to counteract the damage originated from toxic compounds and to prevent their accumulation inside of the cell 3 .…”

“…They are the first site of contact between the cell and toxic compounds which are able to penetrate into cytoplasmic membrane and affect the membrane functions 3,4 . Therefore, bacteria developed adaptation mechanisms to counteract the damage originated from toxic compounds and to prevent their accumulation inside of the cell 3 . Membrane transporters, such as porins or efflux pumps, are main filters regulating the internal accumulation of toxic compounds 4 .…”