Microbial Degradation of Multiwalled Carbon Nanotube By Mycobacterium Vanbaalenii Pyr-1.

Carbonaceous nanomaterials are widely used in industry and consumer products, leading to their release to the environment. Although more than a decade of efforts have been devoted to investigations on the environmental fate and effects of carbonaceous nanomaterials, no existing studies showed significant microbial degradation of these carbonaceous nanomaterials. We found that a polycyclic aromatic hydrocarbon (PAH)-degrading bacteria strain Mycobacterium vanbaalenii PYR-1 is able to degrade and mineralize carboxylic multiwalled carbon-nanotubes (c-MWCNTs), with the rate up to 1 ng c-MWCNT/day/10⁹ cell. The bacteria can be potentially used in engineered system to remove residual CNTs, thus reducing their release to the environment well. Similar degradation of CNTs may occur in natural environments, therefore, predictive fate model and risk regulation for CNTs needs to account for this important reaction pathway of CNT.