Industrially Important Micro-organism
In collaboration with Julian Davies, Bill Mohn, and Lindsay Eltis, we are studying Rhodococcus sp. strain RHA1, one of the best characterized PCB-degraders. This research seeks to investigate the physiology of an industrially important genus of microorganisms, and the effect of engineered enzymes and genes on microbial physiology. Thus, engineering microbial strains for biocatalysis and bioremediation involves genetic modification to introduce or suppress catabolic and/or regulatory activities. The global physiologic consequences of such modifications, both direct and indirect, are often poorly understood. Moreover, other physiological processes may have to be optimized for a bacterial strain to be effective in a particular application. Ultimately, this information will be used to optimize strain RHA1 for bioremedial processes.
This research seeks to investigate the physiology of an industrially important genus of microorganisms, and the effect of engineered enzymes and genes on microbial physiology
Rhodococci are aerobic, Gram positive actinomycetes of high G+C content, capable of morphological differentiation in response to their environment (e.g., cocci or filaments). These widely occurring organisms are of considerable environmental and biotechnological importance due to their broad metabolic diversity and array of unique enzymatic capabilities. These are of interest to the pharmaceutical, environmental, chemical and energy sectors. Specific applications include the desulphurization of fossil fuels and the industrial production of acrylamide. Rhodococci are well suited for bioremediation due to their capacity for long term survival in soil, their exceptional ability to degrade hydrophobic pollutants even in the presence of more readily assimilable carbon sources, and their ability to accumulate high levels of heavy metals.
Rhodococcus sp. RHA1 transforms PCBs using multiple enzyme systems (e.g., it contains at least 7 extradiol dioxygenases) which are encoded on large linear plasmids and different regions of the chromosome. Strain RHA1 is well suited for field applications as it tolerates environmental stresses, survives well in soil and can be genetically manipulated.