Carbonic anhydrase and chemical pollutants: new applied perspectives

Carbonic anhydrase is an ubiquitous metalloenzyme which catalyses the reversible hydration of CO2 to produce H+ and HCO3-. It plays a key role in a number of physiological processes, including acid-base transport, ion transport, bone resorption, calcification, and metabolic processes. The present work is addressed 1) to deepen and discuss a recently emerging aspect of the research on this metalloenzyme such as its sensitivity to chemical pollutants, and 2) to highlight how these studies can yield advancement in developing biologically based methodologies useful for environmental monitoring and assessment applications. Carbonic anhydrase activity showed a high sensitivity to in vitro and in vivo exposure to several heavy metals and xenobiotics in a variety of organisms, including vertebrates and invertebrates, and was demonstrated to be involved in the pollutant induced lysosomal activation in toxicant exposed organisms. These evidenced opened new perspectives for the application of CA as biomarker of pollution exposure, as indicated by the successfully application of CA activity and protein expression measurement in multi-biomarker approaches on bioindicator organisms. Moreover, the in vitro sensitivity of the enzymatic activity to pollutants triggered the development of a new in vitro patented bioassay (MI2008A008813; PCT/IT2013/000205) which has been successfully utilized for the general toxicity detection of environmental aqueous matrices in biomonitoring programs.