Ammonia is abundant in the oceans, in freshwater, soils and the atmosphere and represents the prime resource of usable nitrogen for microorganisms and plants, which provide nitrogen to animals through their consumption. On the other hand, ammonia is considered the most abundant neurotoxin that is present everywhere in the air that we breathe. Therefore, the understanding of mechanisms naturally involved in the consumption of ammonia is key to maintaining a hospitable planet Earth. A grant has been awarded to Dr. Martin G. Klotz of the University of Louisville, in collaboration with Drs. John Heidelberg of The Institute for Genome Research, Karen Casciotti of the Woods Hole Oceanographic Institute, and Bess Ward of Princeton University, to sequence the complete genomes of two proteobacteria that are key players in the marine nitrogen cycle. Both bacteria carry out a similar ecophysiological function in the oceans namely the conversion of ammonia to nitrite and the production of nitrogenous gases that - eventually - will be recycled to benign nitrogen gas. The two researched marine bacteria belong taxonomically to different classes of bacteria; hence their genomes likely contain different molecular bases for nitrification activities. Thus, the unraveling of the genetic make-up of these bacteria will provide us a great deal of insight into the diversity of molecular mechanisms capable of ammonia degradation that have evolved over billions of years in these bacteria. A comparison of this complex genomic information with that from ammonia-oxidizers that function in freshwater or soils will allow future scientific projects to design improved technological strategies for controlled removal of ammonia generated by human activities as well as the identification of targets for the control of such ammonia-oxidizing bacteria where their presence is undesirable (such as in drinking-water production facilities). Work funded through this grant will involve the training of undergraduate and graduate students.
