In Vivo Metabikuc Observation of Aromatic Compounds

The long-term objective is the understanding of aromatic compound degradation by bacteria. This research will provide insight into the environmental and human risks of aromatic compounds following release to the environment. In addition, information gained through this work will be useful in the design and implementation of bioremediative processes. We describe an approach that allows the determination of the metabolic fates of organic compounds utilizing Nuclear Magnetic Resonance (NMR) spectroscopy of in vivo systems. Through complete deuteration of the bacteria, therefore removal of all endogenous resonances, NMR spectroscopy may be used to follow the metabolic rate of any added protonated compound. This approach will further the understanding of the degradation of benzoate through the beta-ketoadipate metabolic pathway in Acinetobacter calcoaceticus, an ubiquitous soil bacterium. This pathway was chosen as a model system for many reasons: the pathway contains 5 of the 6 recognized enzyme classes, the genes have been isolated and sequenced, many mutant strains have been characterized, and A. calcoaceticus is extremely amenable to molecular genetic manipulation. The combined approaches of molecular genetics and NMR spectroscopy will provide clues to the genetic, physiologic and environmental controls of aromatic catabolism in this organism.