TOLERANCE OF PSEUDOMONAS BACTERIA TO SODIUM DODECYL SULFATE

Abstract

The unique ability of Pseudomonas bacteria to grow in the presence of sodium dodecyl sulfate (SDS) allows to use them in the development of the industrial bioprocesses that do not include a sterilization stage. The mechanisms that provide tolerance to SDS can be divided into three groups: aggregation processes, including production of protective polymers and adhesins, the cell wall modification, and synthesis of enzymes that cleave alkyl sulfates. Autoaggregation has a lot of regulation pathways such as SiaABCD transduction and induction of the matrix synthesis with the help of cyclic diguanosine monophosphate. This matrix consists of polysaccharides, nucleic acids and proteins. Fatty acids of the membrane phospholipids can be modified in order to decrease the bilayer solubility in the detergent micelles. Pseudomonads can produce three types of sulfatases capable to metabolize dodecyl sulfate in periplasm and cytosol. The presence of these enzymes provides dynamic equilibrium between SDS uptake and its decomposition, which protects cytosol structures from the interaction with the detergent. Despite all these strategies of tolerance to dodecyl sulfate are well studied, it is still difficult to induce or suppress the detergent resistance. There are only two ways, which can inhibit resistance to SDS without killing the cell. They are suppression of cell respiration, which prevents autoaggregation, and addition of an easily digestible substrate that slows down a sulfatase production.