Microbial perchlorate reduction: Rocket-fuelled metabolism

It is less than 7 years since perchlorate, a predominantly man-made toxic anion, was first identified as a significant water contaminant throughout the United States. Owing to its solubility and non-reactivity, bioremediation was targeted as the most promising solution for the problem of perchlorate contamination. Since 1996, concerted efforts have resulted in significant advances in our understanding of the microbiology, biochemistry and genetics of the microorganisms that are capable of reductively transforming perchlorate into innocuous chloride. The recent completion of the whole-genome sequence of the perchlorate-reducing microorganism Dechloromonas aromatica offers further insight into the evolution and regulation of this unique metabolic pathway. Several in situ and ex situ bioremediative processes have been engineered, and many monitoring tools that are based on immunology, molecular biology and stable isotope content are now available. As such, the rapid scientific response to this emerging contaminant offers great hope for its successful elimination from contaminated environments in the future.