Inducible microbial osmotic responses enable enhanced biosorption capability of cyanobacteria

- Biosorption by cyanobacteria could be enhanced via exerting osmotic stress.
- Exopolysaccharides and carbonic anhydrase activity influenced biosorption.
- Increased biosorption was attributed to induced stress responses.

Microorganisms have evolved series of protective or adaptive responses to enhance survivability to fight against stresses in nature and engineered systems. Although the cellular responses and underlying mechanisms have been intensively studied, seldom research explored the possibilities of employing the microbial stress response via an inducible routine for applications of environmental benefits. In this study, we proposed and demonstrated that the biosorption of methylene blue by cyanobacteria could be enhanced via exerting higher osmotic stress, and the enhanced biosorption is attributed to the induced stress responses which elicited the combined effects of exopolysaccharides over-secretion and the up-regulated carbonic anhydrase activity. To our knowledge, this is the first study that employing the inducible physiological responses of microorganisms for enhanced environmental application, and we believe that this research will bring novel insights into the field of applied microbiology and environmental biotechnology.

111