Microbes Solve Environmental Contamination Problems

The Science

Microbes carry out a wide range of chemical transformations. Understanding the mechanisms of these processes can lead to new biological insights and practical applications. For example, removal of polycyclic aromatic hydrocarbons (PAHs) from contaminated soils is facilitated by microbial degradation. The PAH phenanthrene can be broken down by Arthrobacter phenanthrenivorans, a bacterium isolated from a creosote-polluted site in Greece and that uses phenanthrene as a carbon and energy source. A team of researchers, including a collaborator from the DOE Joint Genome Institute, has purified and analyzed two phenanthrene-breakdown enzymes from this microbe. Based on the similarity of the two genes’ sequences and their common expression in the presence of the PAH, the authors suggest that one of the genes is a duplication of the other even though they are located in very different parts of the genome. Similar results are found in other related bacteria. These types of comparative studies may aid in the design of strategies using microbes for DOE missions or other applications, such as wastewater treatment, biodegradation, and biocatalysis.

References

Vandera, E., K. Kavakiotis, A. Kallimanis, N. Kyrpides, C. Drainas, and A. Koukkoua. 2012. “Heterologous Expression and Characterization of Two 1-Hydroxy-2-Naphthoic Acid Dioxygenases from Arthrobacter phenanthrenivorans,” Applied and Environmental Microbiology 78(3), 621-27. DOI: 10.1128/AEM.07137-11.

Kallimanis, A., K. M. Labutti, A. Lapidus, A. Clum, A. Lykidis, K. Mavromatis, I. Pagani, K. Liolios, N. Ivanova, L. Goodwin, S. Pitluck, A. Chen, K. Palaniappan, V. Markowitz, J. Bristow, A. D. Velentzas, A. Perisynakis, C. C. Ouzounis, N. C. Kyrpides, A. I. Koukkou, and C. Drainas. 2011. “Complete Genome Sequence of Arthrobacter phenanthrenivorans Type Strain (Sphe3),” Standards in Genomic Sciences 4, 123-30. DOI:10.4056/sigs.1393494.