Targeted environmental genomics for biocatalyst discovery

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The microbial world harbours a wealth of DNA sequence information that can be harnessed for the production of bioproducts and enzymes that mediate industrially relevant chemical reactions. In some cases, the biological processes encoded by these gene products can produce high-energy organic compounds that may begin to directly replace fossil fuel-based technologies that are harmful to the environment. For many years, access to the full richness of the genetic material in the microbial world has been hampered by the inability to cultivate most microbes present in microbial communities. Molecular techniques now provide the methods to access the DNA from this uncultivated microbial majority; it is now possible to construct gene libraries from DNA that is extracted directly from a handful of soil, and these libraries then represent the genetic material from each of the microorganisms present in that soil sample. This captured environmental DNA (the 'metagenome') is hosted in readily cultivated bacteria and the corresponding expression of captured genes can be detected and screened for the expression of targeted gene products. In this way, diverse and novel genes from uncultivated microorganisms that carry out desired functions may be exploited, without the prerequisite of cultivation. This proposal describes the establishment of the Canadian MetaMicroBiome Initiative, a publicly accessible collection of libraries of environmental DNA representing Canadian soil microbial communities. Soil samples from disparate Canadian biomes will be chosen due to their unparalleled microbial diversity and corresponding metabolic richness. These DNA libraries will be characterized by powerful DNA sequencing techniques to determine the microbial community diversity of each sample. In partnership with Iogen Corp., we will show that there is DNA of interest in these environmental libraries by isolating new genes for the conversion of lignocellulosic biomass for biofuel and bioproducts applications. Detailed characterization of the enzyme activities and structures will aid in the development or improvement of processes for the production of high value-added chemicals.