Understanding Bioremediation of Metals and Metalloids by Genomic Approaches

Abstract

AbstractSeveral human activities such as urbanization, industrialization, mining activities, agricultural activities, and even transportation lead to the spread and accumulation of many metals and metalloids in soil and water sources directly or indirectly, which harm the health of ecosystems and organisms. Metals and metalloids such as antimony, arsenic, boron, cadmium, chromium, copper, lead, mercury, and zinc appear as contaminants when found locally in concentrations above a threshold level at which they start to exert toxic effects. Bioremediation methods are environmentally friendly, cost-effective, and easy-to-apply and are used to clean up metal and metalloid contaminants from water and soil environments with the help of microorganisms such as bacteria, fungi, algae, and different combinations of such microorganisms. Indigenous microorganisms are especially important as they provide great support to humans in their efforts to remediate the already contaminated ecosystems and to prevent further accumulation of contaminants. Understanding the tolerance mechanisms of microorganisms and the genetic background of the remediation capabilities and discovering novel microorganism species are of importance in the fight against metal contaminants. Genomic approaches shed light on unculturable microorganisms, which have a high potential to accumulate and modify and detoxify metal contaminants in natural environments. Besides discovering tolerant microorganisms, genomic studies also reveal genes and their products that contribute to the tolerance and bioremediation processes. Collecting information about genes and genomes that play a role in building heavy metal and metalloid tolerances will help scientists develop more efficient microorganisms that can be employed in the bioremediation of soil and water ecosystems.KeywordsBioremediationMetalsMetalloidsOmics sciencesGenomics